DIY_EFI Digest Thursday, January 13 2000 Volume 05 : Number 020 In this issue: Re: Turbo motor See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Thu, 13 Jan 2000 09:29:58 -0500 From: "Bruce Plecan" Subject: Re: Turbo motor | | Under boost I have noticed that my car has a tendency to ping more at | 3000 rpm , which I would guess is the tuned configuration of the motor. | So boost and/or timing can be reduced. If the timing is reduced to | prevent any detonation, and the boost is left alone. It will generate | spectacular boost numbers and it runs strong. But it runs about the same | when I reduce the timing a little bit and limit the boost. So it looks | like there are two different ways to get to the same point. So what is | the best way to tune a turbocharger motor? I would guess reducing the | timing a little, and then limit boost to prevent detonation... There's never a good reason to burn more fuel then what the engine needs. All the extra carbon has to go somewhere. If you do EGT's AFR and Plug reading they all should point to one being better than another. | Also I have noticed that GM spark rpm/load tables arrays seem to be 16 | bytes wide, even when its a Grand National turbo motor. It seems like | that if its a one atmosphere map unit the table should be 32 bytes wide | for the same resolution. Any comments on this one? Well, they been running the Buicks since 86 with the intercooler, and making good HP. The syclones since 91. I'd say that the resolution is good enough. Ya, might be nicer, but as far as necessary, that's your call. To me 19 would be perfect, @xxx. The big isue is running the right MAP so you don't run out of CALIBRATION. If ya run 14 PSI of boost run a 2bar MAP. If you run 18 use a 3 bar MAP. That's how I see things Grumpy ------------------------------ End of DIY_EFI Digest V5 #20 **************************** 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".