DIY_EFI Digest Wednesday, May 19 1999 Volume 04 : Number 293 In this issue: Limited cooling space Re: Mr Helmholz - simple model Re: Ignition advance, was Re: alternative engines, WARPED Re: Ignition advance, was Re: alternative engines, WARPED Re: O2 sensor and water Supercharged 440 Re: Ignition advance, was Re: alternative engines, WARPED Re: Ignition advance, was Re: alternative engines, WARPED Re: Ignition advance, was Re: alternative engines, WARPED Re: Ignition advance, was Re: alternative engines, WARPED Re: Ignition advance, was Re: alternative engines, WARPED Re: EGOR, ION, Trionic Re: Limited cooling space RE: Ignition advance, was Re: alternative engines, WARPED Re: Limited cooling space Re: VE tables Re: 1227749 RE: Ignition advance, was Re: alternative engines, WARPED Re: Ignition advance, was Re: alternative engines, WARPED Re: EGOR, ION, Trionic Re: Limited cooling space Re: 1227749 Re: alternative engines, WARPED Re: new auto scam Re: Limited cooling space Re: Limited cooling space Re: Limited cooling space See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Wed, 19 May 1999 07:15:18 -0400 From: "Bruce Plecan" Subject: Limited cooling space Someone the other day mentioned having a very confined area for a radiator. I just recalled one way of "helping". It involves dividing up the radiator so that the coolant rather than just going from side to side has to criss cross the radiator several times. This is done by adding several barriers internal to the side tanks. On the "cold" side of the radiator a divider plate is installed 2/3 of the way down from the top, and on the hot side, a divider is added 1/3 of the way down, so the coolant has to travel back and forth 3 times rather than once. If your out for the gold, you might have to play with the water pump speed, some Grumpy ------------------------------ Date: Tue, 18 May 1999 18:33:10 -0400 From: "Gary Derian" Subject: Re: Mr Helmholz - simple model A megaphone works like a variable length pipe. High frequencies reflect back close in and low frequencies reflect back more towards the larger end. This broadens the sweet spot. 2 stroke engines work very differently. The first part, the diverging area, of the expansion chamber reflects a negative pressure wave to suck the air fuel charge into the exhaust while the transfer ports are still open. This extends the intake cycle. The second part, the converging area, reflects back a positive pressure wave to push it back in after the transfer ports close but the exhaust is still open. A properly tuned pipe makes a 50% to 70% improvement in power. Did the Mercedes actually have a 2 stroke style expansion chamber or were they megaphones with little converging sections at the very end. Grand Prix motorcycles have used diverging/converging megaphones since the 60's but they are not the same as 2 stroke expansion chambers. Gary Derian > >If this opens a whole new box of problems, just ignore. But, I've noticed > >what a huge change expansion chambers have had of VE in 2 strokes, and after > >seeing the Mercedes Benz GT (Sedan, whatever they call em) with the v-6, and > >3 into 1 exhausts, and running 2 expansion chambers (one per side), I just > >wonder, how they came up with that... > > Is it the shape of the cones or volume that makes a "E.C." work, or > >both?. > >Grumpy > > > > Both. Megaphones convert velocity to static pressure pretty efficiently. > > Greg > ------------------------------ Date: Wed, 19 May 1999 07:53:37 -0400 From: "Bruce Plecan" Subject: Re: Ignition advance, was Re: alternative engines, WARPED Kinda depends on the WOT pressure drop across the carb., and spring rate of the vac, advance used. Even with the same no. degrees per amount of vac., by different spring rates/dia. combinations things could vary. Going from 6-10 start to 20 something at 700rpm, 30 something at WOT (@3,000 rpm), and 40ish at cruise with a OD kinda hard to do thata way (mechanical). Hence the real beauty of ecm's, IMHO. Grumpy | I could be wrong at this, but what I have seen is, ported vacuum is dead | at idle, because it is above the butterfly....and as throttle is increased, | vacuum is generated at the "port" and does not go away at full | throttle,,,,,great for emissions but terrible for performance,,,,,the same | for MPG.... | -Carl Summers | You sure about that? I have always understood that a vac advance can | reads ported vacuum in order to affect a curve that begins as the throttle | is opened and increases as more throttle is applied, up to the point at | which all vacuum (manifold and therefore ported as well) fades under heavy | throttle openings, at which point the advance will decline again and the | engine will see only mechanical advance. This is apparently to provide | extra advance for economy at part throttle. Anybody who can further | illustrate this concept, please do because if I am wrong here I'm going to | have some serious rethinking to do! | Aaron Willis ------------------------------ Date: Wed, 19 May 1999 08:03:56 -0400 From: "CLsnyder" Subject: Re: Ignition advance, was Re: alternative engines, WARPED - ----- Original Message ----- From: Aaron Willis To: Sent: Wednesday, May 19, 1999 2:06 AM Subject: Ignition advance, was Re: alternative engines, WARPED > At 12:47 PM 5/18/99 -0400, you wrote: > >Just use manifold vacuum. Carb vacuum is ported so there is no vacuum at > >idle. This can help or hurt the idle quality. Try it and see. > > > >Gary Derian > > > > > You sure about that? I have always understood that a vac advance can > reads ported vacuum in order to affect a curve that begins as the throttle > is opened and increases as more throttle is applied, up to the point at > which all vacuum (manifold and therefore ported as well) fades under heavy > throttle openings, at which point the advance will decline again and the > engine will see only mechanical advance. This is apparently to provide > extra advance for economy at part throttle. Anybody who can further > illustrate this concept, please do because if I am wrong here I'm going to > have some serious rethinking to do! > > > Aaron Willis > ICQ #27386985 > AOL IM: hemiyota > http://surf.to/garage-te51 Garage TE51 International Ported vacuum is also known as Venturi Vacuum. The only time it is zero is with the engine shut off or at idle. As soon as you have airflow you have advance - although it is reduced at WOT. Some implementations just take the vacuum from above the throttle plate and below the venturi. These will lose most of the vacuum at WOT. Switching from port to manifold on a slant six helped the midrange power and driveability considerably, but sure hurt economy. By the way, Aaron - that AOL IM brings back memories. Back when the Golden Triangle Drag Park, or Toronto International Dragway was in operation, Jack Frame Toyota campaigned a little 1972? Corolla 1600 in showroom stock called the Hemiyota. Balanced and blueprinted with open exhaust it kicked major butt. I worked for Fleetline Toyota (Waterloo) at the time. ------------------------------ Date: Wed, 19 May 1999 08:08:03 -0400 (EDT) From: Pat Ford Subject: Re: O2 sensor and water Previously, you (Squash) wrote: > --- Pat Ford wrote: > > I've > > cracked then on my landie and subarus ( the subies > > are > > right at the bottom of the y pipe anything more then > > 8" > > would flood the outside of the sensor and the > > thermal > > gradient popped them (they would leak exhaust). the > > What type of sensor was this? Was it a porcelain or a > steel cased one? the sub was a porcelain one ( looks like a sparkplug) the land rover was stainless steel casing > > Andy > _____________________________________________________________ > Do You Yahoo!? > Free instant messaging and more at http://messenger.yahoo.com - -- Pat Ford email: pford@xxx.com QNX Software Systems, Ltd. WWW: http://www.qnx.com (613) 591-0931 (voice) mail: 175 Terrence Matthews (613) 591-3579 (fax) Kanata, Ontario, Canada K2M 1W8 ------------------------------ Date: Wed, 19 May 1999 08:56:57 -0400 From: "SPECTRO COATING CORP." Subject: Supercharged 440 Walt asked about my comment on the 440 >... & an 8V-71 supercharged & >>injected 440 Chrysler (on the engine stand). > >Jason, what kind of injection are you running on the 440? Above or below >the blower? Does it have a home yet? I believe this is more DIY_EFI related so I'll relay it to the list The 440 is using an Offy 2 - 4bbl intake that has been modified to accept some bolt on injector bosses that I made. I chose the 8V-71 blower to provide clearance for the injectors & rails (it has tapered sides for those of you that haven't seen one) An adapter plate (1/2" aluminum plate) mates the manifold to the blower. I had intended to use a LT-1 ECU and am reworking a cast aluminum front cover to accept the LT-1 cam driven optical distributor. Rob at Force fuel injection told me that i better add enrichment fuel to the top of the blower (roots have low efficiency you know) to provide some additional cooling so I'm working on that now. I dunno how is the best way to drive the additional injectors though - any ideas on an inexpensive additional injector driver would be appreciated (Question - is it possible - or practical - to use an OEM ecu with just enough inputs to make it work as an injector driver) Thers's a lot more to talk about, but I'll let you people ask what you want to hear about. Oh - no there's no home for it yet - I sold my '73 Cuda to my best friend up in Maine. He allowed that we should put it in when i get it done. - Jason ------------------------------ Date: Wed, 19 May 1999 07:07:29 -0600 From: bearbvd@xxx.net (Greg Hermann) Subject: Re: Ignition advance, was Re: alternative engines, WARPED >At 12:47 PM 5/18/99 -0400, you wrote: >>Just use manifold vacuum. Carb vacuum is ported so there is no vacuum at >>idle. This can help or hurt the idle quality. Try it and see. >> >>Gary Derian >> > > > You sure about that? I have always understood that a vac advance can >reads ported vacuum in order to affect a curve that begins as the throttle >is opened and increases as more throttle is applied, up to the point at >which all vacuum (manifold and therefore ported as well) fades under heavy >throttle openings, at which point the advance will decline again and the >engine will see only mechanical advance. This is apparently to provide >extra advance for economy at part throttle. Anybody who can further >illustrate this concept, please do because if I am wrong here I'm going to >have some serious rethinking to do! Sorry Aaron-- Ported vacuum was first used to provide LESS advance at idle so as to decrease idle emissions! (But to still keep more like the ideal advance at cruise.) Regards, Greg > > > Aaron Willis > ICQ #27386985 > AOL IM: hemiyota > http://surf.to/garage-te51 Garage TE51 International ------------------------------ Date: Wed, 19 May 1999 08:27:24 -0400 From: "Gary Derian" Subject: Re: Ignition advance, was Re: alternative engines, WARPED There are two kinds of ported vacuum on carbs. The EGR vacuum works like Aaron described. Its purpose was to gradually feed more EGR as the throttle is opened. Its port is a tall slot in the throttle bore. As the throttle is opened, the throttle plate rises along the slot which feeds more vacuum to the port. The other type of ported vacuum is just a small port above the throttle. As soon as you go above idle, it applies full manifold vacuum. Its purpose is to reduce timing at idle to just the static advance. Not considering emissions, some engines idle smoother with less advance. After 1968, all engines used ported vacuum advance. Before 1968, some did and some didn't. Both types of ported vacuum are limited to the maximum manifold vacuum available and go away as one approaches full throttle. There is also venturi vacuum which is way smaller than manifold vacuum but it increases with air flow. The Ford small in line 6's from the early 60's used some kind of all vacuum distributor connected to both manifold and venturi vacuum (I think). It was claimed to provide improved economy. Venturi vacuum is also used in some EGR control schemes. Gary Derian > Hi all, > I could be wrong at this, but what I have seen is, ported vacuum is dead > at idle, because it is above the butterfly....and as throttle is increased, > vacuum is generated at the "port" and does not go away at full > throttle,,,,,great for emissions but terrible for performance,,,,,the same > for MPG.... > -Carl Summers > > > You sure about that? I have always understood that a vac advance can > reads ported vacuum in order to affect a curve that begins as the throttle > is opened and increases as more throttle is applied, up to the point at > which all vacuum (manifold and therefore ported as well) fades under heavy > throttle openings, at which point the advance will decline again and the > engine will see only mechanical advance. This is apparently to provide > extra advance for economy at part throttle. Anybody who can further > illustrate this concept, please do because if I am wrong here I'm going to > have some serious rethinking to do! > > > Aaron Willis > ICQ #27386985 >> ------------------------------ Date: Wed, 19 May 1999 09:58:50 -0500 From: "G. Scott Ponton" Subject: Re: Ignition advance, was Re: alternative engines, WARPED Everyone has had good points. Put them all together and you about have all the different ways portd vacumn was/is used. Yes there are 3 different "types" and they all work differently. 1. Transfer slot. nothing at idle, large amounts at limited throttle openings, nothing at WOT unless the carb is small for the engine in which case you start getting vacumn at higher engine speeds. 2. Above throttle. Nothing at idle, small amounts at minimal throttle , larger amounts at mid throttle settings, nothing at WOT again size dependant. 3. Venturi. Increasing amounts as air flow increases has vacumn at all throttle openings even WOT. ever wonder why we have spred bore carbs? and why they have better throttle responce etc.? Part of it has to do with avalable vacumn for the ported systems. A simple view. At idle manifold vacumn is confined below the throttle plates. As the throttle is openned manifold vacumn "climbs" to the base of the venturi. Add the chike plate as the last "restriction" to manifold vacumn. Actually ported vacumn was originly used to combat idle instability with a big cam. As the big cam has so little manifold vacumn at idle if a vacumn advance has a low enough spring rate to allow it to stay engaged at idle you started getting it at WOT with single carb apps before the advent of very large single 4bbls. Increase the spring rate to eliminate it at WOT and usually you would run into a situation where the idle vacumn was just enough to give you some advance but not consistantly. As we all know all else being equal, and if the amount of advance isn't excessive, the idle will climb. So sometimes the idle would climb enough to effect even more vacumn raising the idle even further. The opposite was also true less vacumn lower idle etc. I think you can see the point here. As carbs got larg enough to overcome this problem ported vacumn became the norm for both emissions and drivability. See above for part of it. The rest has to do with getting the advance when it is needed the most. Ported systems tend to give you the best of both worlds. Stable, low emissions, idles with propotional vacumn signal at part throttle. Nothing at WOT. So is everyone as confused as I am by my explaination?? LOL Scott ------------------------------ Date: Wed, 19 May 1999 11:08:55 -0400 From: Ken Kelly Subject: Re: Ignition advance, was Re: alternative engines, WARPED Good response! However, there were a few engines in the 70's that didn't used ported advance. The Oldsmobile 350 "R" engine from 76-78 was an example. My 77 Olds 350R always failed the NJ State Emmissions test by 10% high HC because it used manifold vacuum for advance at idle. If I plugged the vacuum advance, and reset the idle speed to stock, it would pass at about half the state HC level, but the milage and drivability were terrible! It was a common problem with these engines, and the emmission test. However in stock form it was one of the most responsive late 70's engine, and it had great gas milage. After owning it for 17 years and 17 inspections I got to be able to switch it back and forth in 5 minutes. Ken Gary Derian wrote: > > There are two kinds of ported vacuum on carbs. The EGR vacuum works like > Aaron described. Its purpose was to gradually feed more EGR as the throttle > is opened. Its port is a tall slot in the throttle bore. As the throttle > is opened, the throttle plate rises along the slot which feeds more vacuum > to the port. The other type of ported vacuum is just a small port above the > throttle. As soon as you go above idle, it applies full manifold vacuum. > Its purpose is to reduce timing at idle to just the static advance. Not > considering emissions, some engines idle smoother with less advance. After > 1968, all engines used ported vacuum advance. Before 1968, some did and > some didn't. Both types of ported vacuum are limited to the maximum > manifold vacuum available and go away as one approaches full throttle. > There is also venturi vacuum which is way smaller than manifold vacuum but > it increases with air flow. The Ford small in line 6's from the early 60's > used some kind of all vacuum distributor connected to both manifold and > venturi vacuum (I think). It was claimed to provide improved economy. > Venturi vacuum is also used in some EGR control schemes. > > Gary Derian > > > Hi all, > > I could be wrong at this, but what I have seen is, ported vacuum is > dead > > at idle, because it is above the butterfly....and as throttle is > increased, > > vacuum is generated at the "port" and does not go away at full > > throttle,,,,,great for emissions but terrible for performance,,,,,the same > > for MPG.... > > -Carl Summers > > > > > > You sure about that? I have always understood that a vac advance can > > reads ported vacuum in order to affect a curve that begins as the > throttle > > is opened and increases as more throttle is applied, up to the point at > > which all vacuum (manifold and therefore ported as well) fades under > heavy > > throttle openings, at which point the advance will decline again and the > > engine will see only mechanical advance. This is apparently to provide > > extra advance for economy at part throttle. Anybody who can further > > illustrate this concept, please do because if I am wrong here I'm going > to > > have some serious rethinking to do! > > > > > > Aaron Willis > > ICQ #27386985 >> ------------------------------ Date: Wed, 19 May 1999 10:14:17 -0700 From: "Todd....!!" Subject: Re: Ignition advance, was Re: alternative engines, WARPED Venturi vac is not considered to be the same as ported vacuum, The venturi's are up in the top of the carb, the ports are way down in the manifold... two TOTALLY different vac readings... The vac advance vacuum should be from a vac source which is located between the throttle blades and the intake valves... known as port vac.. CL, your theory is pretty correct, for a naturally aspirated car with no form of ram air... However, with a turbo/supercharged/SERIOUS ram air car(at high speed) manifold vac can read anywhere from neg to pos...depending on the conditions... On the turbo/supercharged cars, if the timing isn't controlled by computer, then the vac must be pulled from a different source... Sincerely, Todd....!! - ----- CLsnyder wrote: > > ----- Original Message ----- > From: Aaron Willis > To: > Sent: Wednesday, May 19, 1999 2:06 AM > Subject: Ignition advance, was Re: alternative engines, WARPED > > > At 12:47 PM 5/18/99 -0400, you wrote: > > >Just use manifold vacuum. Carb vacuum is ported so there is no vacuum at > > >idle. This can help or hurt the idle quality. Try it and see. > > > > > >Gary Derian > > > > > > > > > You sure about that? I have always understood that a vac advance can > > reads ported vacuum in order to affect a curve that begins as the throttle > > is opened and increases as more throttle is applied, up to the point at > > which all vacuum (manifold and therefore ported as well) fades under heavy > > throttle openings, at which point the advance will decline again and the > > engine will see only mechanical advance. This is apparently to provide > > extra advance for economy at part throttle. Anybody who can further > > illustrate this concept, please do because if I am wrong here I'm going to > > have some serious rethinking to do! > > > > > > Aaron Willis > > ICQ #27386985 > > AOL IM: hemiyota > > http://surf.to/garage-te51 Garage TE51 International > > Ported vacuum is also known as Venturi Vacuum. The only time it is zero is > with the engine shut off or at idle. As soon as you have airflow you have > advance - although it is reduced at WOT. Some implementations just take the > vacuum from above the throttle plate and below the venturi. These will lose > most of the vacuum at WOT. > > Switching from port to manifold on a slant six helped the midrange power and > driveability considerably, but sure hurt economy. > > By the way, Aaron - that AOL IM brings back memories. Back when the Golden > Triangle Drag Park, or Toronto International Dragway was in operation, Jack > Frame Toyota campaigned a little 1972? Corolla 1600 in showroom stock called > the Hemiyota. Balanced and blueprinted with open exhaust it kicked major > butt. I worked for Fleetline Toyota (Waterloo) at the time. ------------------------------ Date: Wed, 19 May 1999 11:34:47 -0400 (EDT) From: "Clive Apps Techno-Logicals 416 510 0020" Subject: Re: EGOR, ION, Trionic is anyone on this list in the vicintity of Charles City VA I have a source for a bunch of defective Trionic (SAAB) modules you would have to go pick them up email off list for details clive@xxx.com Clive ------------------------------ Date: Wed, 19 May 1999 10:19:49 -0700 From: "Todd....!!" Subject: Re: Limited cooling space I confir... Great idea Bruce, I'm thinkin about doin at LEAST one block plate in my 440 Bee... However I have a top and bottom radiator in it now, that may hender this theory a bit... Will be researchin this type setup.... LATER! Todd....!! Bruce Plecan wrote: > > Someone the other day mentioned having a very confined area for a radiator. > I just recalled one way of "helping". > It involves dividing up the radiator so that the coolant rather than just > going from side to side has to criss cross the radiator several times. > This is done by adding several barriers internal to the side tanks. On > the "cold" side of the radiator a divider plate is installed 2/3 of the way > down from the top, and on the hot side, a divider is added 1/3 of the way > down, so the coolant has to travel back and forth 3 times rather than once. > If your out for the gold, you might have to play with the water pump > speed, some > Grumpy ------------------------------ Date: Wed, 19 May 1999 10:39:44 -0500 From: Don.F.Broadus@xxx.com Subject: RE: Ignition advance, was Re: alternative engines, WARPED The problem with going to manifold vac on some HEI's is that the vac can has as much as 25 degrees (crank) advance built in. with say 12 degrees initial you have 37 degrees at idle, then when you start to get into it the cent. advance starts and the knocken commences. If you go manifold vac change the can to one with 10 degrees (crank). Now you have 22 degrees (crank) changing to lighters springs will bring the cent curve in quicker also. Don > -----Original Message----- > From: bearbvd@xxx.net] > Sent: Wednesday, May 19, 1999 8:07 AM > To: diy_efi@xxx.edu > Subject: Re: Ignition advance, was Re: alternative engines, WARPED > > >At 12:47 PM 5/18/99 -0400, you wrote: > >>Just use manifold vacuum. Carb vacuum is ported so there is no vacuum > at > >>idle. This can help or hurt the idle quality. Try it and see. > >> > >>Gary Derian > >> > > > > > > You sure about that? I have always understood that a vac advance > can > >reads ported vacuum in order to affect a curve that begins as the > throttle > >is opened and increases as more throttle is applied, up to the point at > >which all vacuum (manifold and therefore ported as well) fades under > heavy > >throttle openings, at which point the advance will decline again and the > >engine will see only mechanical advance. This is apparently to provide > >extra advance for economy at part throttle. Anybody who can further > >illustrate this concept, please do because if I am wrong here I'm going > to > >have some serious rethinking to do! > > Sorry Aaron-- > > Ported vacuum was first used to provide LESS advance at idle so as to > decrease idle emissions! (But to still keep more like the ideal advance at > cruise.) > > Regards, Greg > > > > > > Aaron Willis > > ICQ #27386985 > > AOL IM: hemiyota > > http://surf.to/garage-te51 Garage TE51 International > ------------------------------ Date: Wed, 19 May 1999 09:54:39 -0600 From: bearbvd@xxx.net (Greg Hermann) Subject: Re: Limited cooling space >Someone the other day mentioned having a very confined area for a radiator. >I just recalled one way of "helping". >It involves dividing up the radiator so that the coolant rather than just >going from side to side has to criss cross the radiator several times. > This is done by adding several barriers internal to the side tanks. On >the "cold" side of the radiator a divider plate is installed 2/3 of the way >down from the top, and on the hot side, a divider is added 1/3 of the way >down, so the coolant has to travel back and forth 3 times rather than once. > If your out for the gold, you might have to play with the water pump >speed, some >Grumpy Grumpy-- You been checking out the radiator set-up on some of the late model, aero nose K-Whoppers? Greg ------------------------------ Date: Wed, 19 May 1999 12:45:17 -0400 From: "David A. Cooley" Subject: Re: VE tables > > Is your goal in reducing teh amount of fuel to find that fine line > between extra fuel cooling teh conbustion vs. loadin up the cylinder > with extra fuel? or what? Just wonderinnnnnnnn........ Just trying to tune for max performance... Superchips bumped the VE from 85-90% to 100-105% through most of the upper RPM ranges... Mileage dropped and setting PE VS RPM to 0% (from 10%) still has O2 voltages at ~900mv at WOT. I had to go to about -15% before it dropped to the 800-850mv range... Stock, the chip was too rich at WOT, now it's bunches richer. ------------------------------ Date: Wed, 19 May 1999 13:22:15 -0400 From: Frederic Breitwieser Subject: Re: 1227749 > What diameter and wall thickness was the tubin ya used? I used suspension tubing, which is 3/4" outer diameter tubing, with a inner diameter suitable for threading 1/2", so its slightly less than 1/2" internal diameter. Buy, clamp, and tap. Couldn't be any easier for that part. Welding on blocks to mate with the injector was a little more complex, but not impossible. TIG weld or use www.durafix.com. I've found out the hard way that MIG welding aluminum is set aside for welding gods. > Aren't they usually billet rails? or are the billet rails just show Billet is pretty. But I can polish my aluminum rod, so no big deal. - -- Frederic Breitwieser Bridgeport CT 06606 1993 Supercharged Lincoln Continental 1989 HWMMV w/turbocharged 500cid Caddy 1975 Dodge D200 Club Cab soon to have 431 stroker + turbos 2000 (I hope) Buick GTP (Mid-Engined Sports Car) ------------------------------ Date: Wed, 19 May 1999 10:21:33 -0700 From: Aaron Willis Subject: RE: Ignition advance, was Re: alternative engines, WARPED At 10:39 AM 5/19/99 -0500, you wrote: >The problem with going to manifold vac on some HEI's is that the vac can has >as much as 25 degrees (crank) advance built in. >with say 12 degrees initial you have 37 degrees at idle, then when you >start to get into it the cent. advance starts and the knocken >commences. If you go manifold vac change the can to one with 10 degrees >(crank). Now you have 22 degrees (crank) changing to lighters springs will >bring the cent curve in quicker also. > Don > Obviously not an HEI, but my '72 MGB was set like this as well, and acted just the same. Recently found out that this was the case and that the vacuum should have been ported, which is why I put my hand up on this post in the first place. Aaron Willis ICQ #27386985 AOL IM: hemiyota http://surf.to/garage-te51 Garage TE51 International ------------------------------ Date: Wed, 19 May 1999 10:32:32 -0700 From: Aaron Willis Subject: Re: Ignition advance, was Re: alternative engines, WARPED At 07:07 AM 5/19/99 -0600, you wrote: >> You sure about that? I have always understood that a vac advance can >>reads ported vacuum in order to affect a curve that begins as the throttle >>is opened and increases as more throttle is applied, up to the point at >>which all vacuum (manifold and therefore ported as well) fades under heavy >>throttle openings, at which point the advance will decline again and the >>engine will see only mechanical advance. This is apparently to provide >>extra advance for economy at part throttle. Anybody who can further >>illustrate this concept, please do because if I am wrong here I'm going to >>have some serious rethinking to do! > >Sorry Aaron-- > >Ported vacuum was first used to provide LESS advance at idle so as to >decrease idle emissions! (But to still keep more like the ideal advance at >cruise.) > >Regards, Greg Right right right, that's what I said! The vacuum advance curve BEGINS (meaning at idle there is none) as the throttle is opened, and increases with higher throttle openings as mentioned above. Maybe I wasn't totally clear on that. Thanks everybody for clearing this up... Aaron Willis ICQ #27386985 AOL IM: hemiyota http://surf.to/garage-te51 Garage TE51 International ------------------------------ Date: Wed, 19 May 1999 13:37:55 -0400 (EDT) From: Pat Ford Subject: Re: EGOR, ION, Trionic Previously, you (Clive Apps Techno-Logicals 416 510 0020) wrote: > > is anyone on this list in the vicintity of Charles City VA > I have a source for a bunch of defective Trionic (SAAB) modules > I'd be interested but I'm up in Canada 8( > you would have to go pick them up > > email off list for details if you find someone could you have them pick one up for me? > > > clive@xxx.com > > Clive > - -- Pat Ford email: pford@xxx.com QNX Software Systems, Ltd. WWW: http://www.qnx.com (613) 591-0931 (voice) mail: 175 Terrence Matthews (613) 591-3579 (fax) Kanata, Ontario, Canada K2M 1W8 ------------------------------ Date: Wed, 19 May 1999 13:49:54 -0400 From: "Gary Derian" Subject: Re: Limited cooling space The way I see it, the coolant now "sees" a radiator that is 1/3 as high and 3 times longer. Why does this cool better than normal. The log delta T is the same, no? Is it a flow turbulence thing? That is the only change I see. Gary Derian > >Someone the other day mentioned having a very confined area for a radiator. > >I just recalled one way of "helping". > >It involves dividing up the radiator so that the coolant rather than just > >going from side to side has to criss cross the radiator several times. > > This is done by adding several barriers internal to the side tanks. On > >the "cold" side of the radiator a divider plate is installed 2/3 of the way > >down from the top, and on the hot side, a divider is added 1/3 of the way > >down, so the coolant has to travel back and forth 3 times rather than once. > > If your out for the gold, you might have to play with the water pump > >speed, some > >Grumpy > > Grumpy-- > > You been checking out the radiator set-up on some of the late model, aero > nose K-Whoppers? > > Greg > ------------------------------ Date: Wed, 19 May 1999 13:20:11 -0400 From: Frederic Breitwieser Subject: Re: 1227749 > Sounds like Fred got one of his from a TURBO SUNBIRD... That I did! The 7749's are in several vehicles... check Ludis's detailed site and you can see. I tried to cut and past but for some reason Windows blew up. http://www.cruzers.com/~ludis/p4xref.html#1227749 - -- Frederic Breitwieser Bridgeport CT 06606 1993 Supercharged Lincoln Continental 1989 HWMMV w/turbocharged 500cid Caddy 1975 Dodge D200 Club Cab soon to have 431 stroker + turbos 2000 (I hope) Buick GTP (Mid-Engined Sports Car) ------------------------------ Date: Wed, 19 May 1999 13:31:50 -0400 From: Frederic Breitwieser Subject: Re: alternative engines, WARPED > cyl wall thickness and safety THEN DE_STROKIN the sucker to a shorter > stroke than a 350 chev!! I think you are making this too complicated... If you want the B block, do up a 400cid block with a 440 steel crank, 440 YJ rods, and wiseco pistons. The crank journals get turned down to the right diameter to match the B block, and there you have it... a 451 stroker engine. Better yet, use the 383 block which certain years have thicker cyl walls, stroke it to 431 cid, then add two turbos. Watch my taillights :) Picture a hair over 700 HP at a mere 4200 RPM. > The 400 Mopar is where it's at if ya want a high revvin engine! Why rev? The "jerk" force at the top of the stroke, when the crank starts to bring the piston down, increases exponentially with RPM increases. So, keep the RPMs low, boost the hell out of it, and get your power that way. You'll break less parts in the long run. Based on a past life I revved 500cid blocks all the way into the 10k's and look at all the pretty, overpriced, titanium parts that flew all over. > into the 400 block and create a REALLY lightweight internal 451 stroker > motor! Using aluminum pistons make things even lighter, at a tradeoff of piston skirt expansion, thus requiring more clearance in the bores, thus more blow-by until things heat up to operating temperature. > to the law of supply and demand, more people but chev's and Fordsouta > the yards than Mopars... For V8 engines, that's true here in Connecticut too. - -- Frederic Breitwieser Bridgeport CT 06606 1993 Supercharged Lincoln Continental 1989 HWMMV w/turbocharged 500cid Caddy 1975 Dodge D200 Club Cab soon to have 431 stroker + turbos 2000 (I hope) Buick GTP (Mid-Engined Sports Car) ------------------------------ Date: Tue, 18 May 1999 21:48:21 +0100 From: Clint Sharp Subject: Re: new auto scam Talking of scams, can anyone confirm my suspicion that Broquet fuel catalyst pellets are a scam? I have searched the web and found very little info apart from the stuff the manufacturer and distributors publish. - -- Clint Sharp ------------------------------ Date: Wed, 19 May 1999 15:45:32 -0400 From: Frederic Breitwieser Subject: Re: Limited cooling space > The way I see it, the coolant now "sees" a radiator that is 1/3 as high and > 3 times longer. Why does this cool better than normal. The log delta T is > the same, no? Is it a flow turbulence thing? That is the only change I > see. Here would be my guess... If you increase the width of the radiator, the coolant has to move further to reach the other side and be sucked back into the system, therefore its exposed to the ambient (and hopefully cooler) air temperature, which reduces the temperature of the coolant going back in. While my dilbert-cube-mates think I'm insane, I just tried something that you can do that will illustrate the point. Run the hot water on your faucet for a few minutes, until the temperature is constant. Stick a thermometer into a coffee mug, then fill it with hot water. Record temperature. Then, using a second thermometer, or cool off the first one to room temperature, repeat the experiment, however use the hose with the spray gun, which typically has 5-6 feet of hose under it. The temperature in the mug is consistantly 5-6 degrees colder. I did this 3 times to make sure. Longer hose, more distance traveled, more energy (heat) lost or radiated into "space". - -- Frederic Breitwieser Bridgeport CT 06606 1993 Supercharged Lincoln Continental 1989 HWMMV w/turbocharged 500cid Caddy 1975 Dodge D200 Club Cab soon to have 431 stroker + turbos 2000 (I hope) Buick GTP (Mid-Engined Sports Car) ------------------------------ Date: Wed, 19 May 1999 15:06:41 -0500 From: steve ravet Subject: Re: Limited cooling space Frederic Breitwieser wrote: > > > The way I see it, the coolant now "sees" a radiator that is 1/3 as high and > > 3 times longer. Why does this cool better than normal. The log delta T is > > the same, no? Is it a flow turbulence thing? That is the only change I > > see. > > Here would be my guess... > > If you increase the width of the radiator, the coolant has to move > further to reach the other side and be sucked back into the system, > therefore its exposed to the ambient (and hopefully cooler) air > temperature, which reduces the temperature of the coolant going back > in. But, heat lost is proportional to the temperature delta. As the water passes through this longer radiator you dump less and less heat because the temp delta is getting closer to zero. Maybe Gary can weigh in here but I think you want the radiator at the highest possible average temperature to maximize heat transfer. That situation is achieved by the "parallel" radiator, not the serial radiator. - --steve - -- Steve Ravet steve.ravet@xxx.com Advanced Risc Machines, Inc. www.arm.com ------------------------------ Date: Wed, 19 May 1999 16:37:46 -0400 From: "Gary Derian" Subject: Re: Limited cooling space The coffee mug experiment does not duplicate the radiator conditions. It is no surprise that water that travels through a few feet of hose and a spray head is cooler than water that does not. In the radiator, the average residence time is the same each way, 3x speed for 3x distance vs. 1x speed for 1x distance. Wouldn't the OEM's build radiators this way if it were better? Of course they would make it smaller to save money for the same cooling. Gary Derian > > The way I see it, the coolant now "sees" a radiator that is 1/3 as high and > > 3 times longer. Why does this cool better than normal. The log delta T is > > the same, no? Is it a flow turbulence thing? That is the only change I > > see. > > Here would be my guess... > > If you increase the width of the radiator, the coolant has to move > further to reach the other side and be sucked back into the system, > therefore its exposed to the ambient (and hopefully cooler) air > temperature, which reduces the temperature of the coolant going back > in. > > While my dilbert-cube-mates think I'm insane, I just tried something > that you can do that will illustrate the point. > > Run the hot water on your faucet for a few minutes, until the > temperature is constant. Stick a thermometer into a coffee mug, then > fill it with hot water. Record temperature. > > Then, using a second thermometer, or cool off the first one to room > temperature, repeat the experiment, however use the hose with the > spray gun, which typically has 5-6 feet of hose under it. The > temperature in the mug is consistantly 5-6 degrees colder. I did this > 3 times to make sure. > > Longer hose, more distance traveled, more energy (heat) lost or > radiated into "space". > > -- > > Frederic Breitwieser > Bridgeport CT 06606 > > 1993 Supercharged Lincoln Continental > 1989 HWMMV w/turbocharged 500cid Caddy > 1975 Dodge D200 Club Cab soon to have 431 stroker + turbos > 2000 (I hope) Buick GTP (Mid-Engined Sports Car) ------------------------------ End of DIY_EFI Digest V4 #293 ***************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace "diy_efi-digest" in the command above with "diy_efi".