[Diy_efi] False knock?

[sy2th]

I'm certainly no expert here, my experience is w/ 4.3L Syclone running the 
same & slightly higher boost figures.  175psi compression sounds a mite 
high for that boost; my brand new 4.3 @ 8.35:1 CR reads 165#.  Maybe carbon 
buildup has raised your CR to unacceptable levels?  I use the FJO WB also & 
get best power @ 12.0:1 - 12.2:1, although that's with 25% (v/v) 
methanol/water injection added, so they're just numbers, not true 
AFRs.  Just a thought....

Barry - Sy#26
Bangor, MI

At 09:11 PM 11/5/02 -0500, Grant Beaty wrote:
>I re-did the repair manuals knock sensors tests and both check out ok, 
>.123ms period at 4k RPMs. Timing advance still plummets when the car is 
>leaned out past 10.8:1 or so, at boost levels from 14 to 19 psi. This has 
>been verified by 3 different wideband O2s. The car's compression is 
>perfect, 172-175 across the board, no visible blow-by anyways, and it 
>burns no oil. The car actually lost power going from 10.7 to 12.0 a/f on 
>the dyno, 450 rwhp to 445 (although it picked up some torque before it 
>pulled ~4 degrees of timing). All other Supras I've heard of pick up some 
>power when leaned out, even on pump gas, and even past 12.5:1, as long as 
>its only for one dyno pull.
>
........


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