[Supras] boost pulling timing

[berniek at technicaldevelop.com]

I've wrestled with this issue too, running a Lex and 550cc injectors, 57 
trim CT26, 3" turbo back exhaust, 15-17 PSI boost, IC upgrade to come, 
some hardpipes, all with the stock ECU, trimming fuel pressure and the 
Lex bypass.  In a word, the pressure transducer at least in '90 and '91 
applications only operates the dash gauge, nothing more (it will operate 
up to almost 15 PSI at about 14.9V output if you rescale the gauge 
circuitry to match it).  That leaves the knock sensors to retard timing 
if and when needed under higher boost.  I believe Jeff Corbat is running 
a setup like this with a stock turbo and has had no problems.  I've had 
no codes set ever (in all of 500 miles, lol, but some of it before the 
snow under really punishing conditions.


    Bernie


PS:  I believe I might have an earlier ECU which might explain slight 
mixture dependence upon temperature and faster idle with the lights on.  
Once when I did not catch second gear upshifting in time, it spun to 
6500 RPM, which '91's with fully counterweighted crankshafts are not 
supposed to do.  My '90 stuttered at 6200.