Does any one know the particulars of this manifold? It came out of a 1985, I converted it over to speed density. I got it running no problem, but I need to know about fuel pressure, tps voltage, base timming, and any thing else I can set that will affect the way she runs. I also installed a set of bosch (ford) injectors

The engine basicly stock 30 over, edelbrock alum. heads, no emmissions, small cam for a tpi engine, true dual exhaust, stock ignition.

What would make the idle float up an down after it runs for a little bit?

Every one I ask gives me different answers, hoping one of you guys the have done this can help me out!!

 

I had the TPI on my '91. The fuel pressure runs about 45lbs, the idle is controlled by the Idle Controll Sensor on the side of the throttle body. You did good going with the Ford injectors MUCH better than OEM. Not sure about the TPS volts, but I want to say timing was at 6 degrees.

Ask in the C4 Tech section as well, many TPI owners there.

 

eratic idle is from you TPS sensor. make sure your IAC
is good to.

 

Do you have the book 'TPI Swappers Guide'? Might also try "How to tune and modify Chevy TPI engines'.

 

OK, with engine still, and fuel pump jumpered to the horn relay distribution point, I get 12 volts at the pump, and set the adjustable regulator for 42 PSI.....

pull the throttle body and clean ALL passages, including the IAC for all traces of carbon/dirt/oil crap....when i't's squeeky clean assemble again....

with engine running at hot idle, turn off the engine, turn it back on but DO NOT START, jumper the ALDL points together for moving the IAC motor to the fully closed poistion, unplug the IAC and, then start engine, it may take a bit to keep it running, and if you have a cam that idles above the idle setting in the computer chip, you may have a problem with it staying lit.....fight it best you can....what you need do is set the idle for about 150 rpms less than the chip calls for, engine may run like crap, but that's life....

turn off engine and rehook everything, release power to computer in the main line fuse, or disconnect battery....
wait about 3 minits, rehook everything and fire it up....let warm up to full temp, and check top pin of TPS for 5 volts dc....then check middle terminal...gray I think, for .5 volts,, that's 1/2 volt with engine idleing and throttle in normally closed position...that's it for the TPS...
with engine still and ignition on, check the TPS does go to 4.5 volts at WOT, never seen one that didn't, but it's a check point anyway....

this should cure your idle problems, if not, lemme know, we go IM...

GENE

 

BTW An intake leak, and there is A LOT of places for it leak, can cause erratic idle.