I finally got my slp runners installed with new oem gaskets. I also installed a ported plenum and I also pain stakenly port and matched all the gaskets to the plenum and runners. I reassembled everything afterwards and reset the tps and minimum air. Today I finally started the iroc up and she roared and I let the car idle for a while checking for leaks and etc. Well my question is this before my endeavor with the stock plenum and runners my idle was around 800 rpm,s in park and about 600rpm's in drive. This through me though now in park the rpm is around 650 and drive 500rpm's. This may sound nuts though I can hardly tell the engine is running. The idle is very smooth and the tach barely moves. Could this be due to now having new gaskets and no leaks as compared before with the stock upper intake. I have never had to adjust the idler screw and is still set to stock setting. I took it for a ride so the ecm could relearn everything and she idled at about 550rpm's no prob and the acceleration was unbelievable. So am I worrying for nothing or what? thanx

 

On an original TPI engine from 1988 I beleive they did indeed call for a very low ~550 RPM in-gear idle in the chip programming. My 88 TPI cars all idled way down aroud there when they were stock.

If you had vacuum leaks before then that could certainly have caused a higher idle speed.

 

Right, you could of had a vacuum leak from before and now you have fixed it without knowing. Allen