Hopefully I'll get to drive it tonight. I'm just finishing up what started out as a cam swap.


New parts:
Combination Motorsports TN-236XL, 236/242, .555/.576, 112
Comp 987 Valve springs, 10* locks/retainers
Cloyes Double Roller timing set
CSR Electric waterpump
Speed Pro PowerForged Pistons
-4.030", flattop, approx. 11:1 CR
MadZ28 tune

I'm hoping for 12.2's with the setup now, will find out next weekend.

 

rock on.

 

sounds good

 

SHE LIVES!!!!!!

haha, been running her while its still up on jackstands all afternoon, setting the rockers, fixing exhaust leaks, etc.


Haven't had a chance to drive it yet, but damn is this a rowdy cam Won't idle smoothly below about 850, even at 950 its a little jumpy. Hopefully it drives smoothly. We'll see. I'll post some vid/sound clips tomorrow

 

so much for that

Got some serious driveability issues I can't sort out. At idle I'm getting 75 kPa on the MAP, IAC is maxed out at 160, and I have to use the throttle body set screw to keep it from idling at 600. I get a MAP High code and it won't go closed loop. Apparently both O2's somehow went bad at the same time

Guess I'll pull the timing cover back off tomorrow and double check I've got everything lined up right and that the opti is/was on correctly.

Any ideas?

 

Any updates?

 

yup. Opti *appeared* to be on correctly, timing chain was dead on. I played around with the Opti some as I was putting it back on, testing to see if there was anyway to put it back on with it in the incorrect position and I don't see anyway possible besides one of the other slots.

Before I run it again I'm going to pull the spark plugs and see if I find any obvious indications of a cylinder being down.

Will update again when I know more.


*Also, I replaced the intake gaskets first thinking that might be the problem but there was no change.


**One thing I'm considering now is if something is blocking the IAC port or if the IAC is stripped out or something. The computer is trying to give it more air to idle *I think*, hence why its going out to 160. But I would think it would come back down if I cracked the throttle blades, which it doesn't.

 

FOUND THE PROBLEM! I think.

So I think now it was a combination of the BBK throttle body not having an IAC bypass passage and the MAF being bad. I drilled the bypass and disconnected the MAF, everything seems pretty good. I still need to replace the right O2, but overall I think I've nailed it. Going to call around tomorrow and see how much I can get a MAF for.