I just took the 88 to the track after my ZZ3 swap. First off, it is a ZZ3 crate, 700R4, and 3.42 gears. I am running a stock TPI intake and 350 PROM, with 24lb SVO injectors, hedman headers and 2 1/2" y-pipe, and stock diameter cat and catback with 2" tailpipes that some idiot put on there. The best time I ran was a 14.43@94 MPH with a 2.09 60'. It was a very cool, dry night at around 84 degrees. This dosent seem right. Everything I heard about the "ZZ" engine swaps with TPI, the cars are running mid-high 13's all day long. I am also at seal level here in Phoenix. I an running a stock converter and only had about 2 feet of tire spin at the line. Do you think my exhaust system could be holding me back that much? Also, I know I have a bad O2 sensor. Is that ignored at WOT or is it still reading it? I need to know where to look, as this is very embarrasing. Let me know what you think. THX

 

I am not really the prom tuner type but a good friend of mine did a ZZ? swap in a GTA about eight or nine years ago and never really got it running any faster than you. Like you he was disapointed but I have seen those engines fly when carbed so my guess is the tuning is not dialed in. Likely the stock TPI intake is choking it down more than the exhaust. I know one thing that made a difference I believe was changing the knock sensor as the stocker was too sensitive. I have heard the Z06 knock sensor is the one to use. I am sure others will have more insight to this than I with regards to the prom/tuning of the TPI but your 94MPH is way to slow for a 350 horse engine... should be over 100 at least. Good luck

 

You are not going to be going much faster without a prom or at the very minimum, an adjustable fuel pressure regulator and a way to (monitor) your O2 readings at WOT. Single cat is killing your performance. Remove it for the track. You didnt mention if you did any modifications to your TPI before bolting on the new motor. There are MANY improvements that can be made to that intake that a person with no experience can make. Check out the "Common First Mods" Section of the EVERYONE READ FAQ at the beginning of this board.

FYI, we are not at sea level in Phoenix. Speedworld is at 1250ft and Firebird is about the 1000.

 

Bout choked! 84 is bout as warm as it ever gets here in the summer.. during the day. Last october our crew met at the track and it was a "very cool" 32 degrees!

 

Run it again with the cat disconnected from the Y-pipe and see what kind of mph that nets you. If its like 4-5 mph its safe to say you need a new catback.

 

Desert86Roc: Where can I get a PROM for my car? I noticed you are running a TPI 406...did you have one burned, or did you just go with an aftermarket company? Also, how can these people get regular L98's into the 13's with the stock PROM? I am kinda new to the whole TPI thing, so I'll accept any suggestions. THX again

 

I had to burn my own. Making minor changes to what you have, you should be able to run quicker and make your setup more efficient. Email me and we can talk about your setup in more detail.

 

What is the timing set at on your car? With your stock TPI setup you will want to limit it to 10* advance. If you are only leaving two feet of rubber, either you have very tall gears or you are probably running way too much timing. I have a very serious traction problem off the line. I can only launch at half throttle and then nail it after I'm running. Consequently, I only run a 2.00 0-60. I would love to try slicks just one night!!!!!!

Also, as mentioned already:

Put a 3" cat back on the car for street use.

Add a 3" cutout in front of the converter so you can "uncork" it at the track.

BTW, the stock chip stinks with that cam..... BAD!!!!!!

If you have the high gears, you might want to consider going to some 3.42 gears to get some more pull in 3rd.

If you don't have the coated headers, run a heated 02 sensor. I have the coated headers, but I'm going to change over anyway.

Gut the air cleaner assembly and install some K&N filters. You may or may not want to try running with no filter at the track. Seems like it was worth a tenth..... For a while I used a 4"x10" rectangle to (90* angled) 6" round duct for a house airconditioning duct underneath my filters. They fit in place of the fog lamps almost perfectly and they end up about an inch below your filters. Not a sealed ram air system, but they helped. They will also fill your filters full of bugs rather quickly when driven on the street.

 

That is very helpful. I do have 3.42 gears, and I am ordering my 3" Edelbrock catback today. I am also going to put a section of pipe in place of the cat until next August (emissions). Come to find out the cat is a 2 1/4 aftermarket piece. Im gonna put the 2400 converter in, and the full exhaust with the new O2 sensor and take it out again.

 

It will run pig rich until you change the injector constant in the PROM to compensate for the bigger injectors.

But Desert86Roc has probably already told you that.

 

I ordered my catback today. 3" Flowmaster catback with 3" tailpipes and stainless tips. As soon as I can figure out this whole PROM thing, ill take it out there again and see what she does. I also put in a 2400 converter on Saturday. It seems to launch a lot better than the stock 1350. LOL. I actually read an article this weekend in an old chevy magazine where they had a 87 Camaro with basically a ZZ4 short block, ZZ9 cam, 1.6 rockers, 2500 stall, and 3.42 gears and were running a best of 12.38 at 110mph N/A. That was obviously with full exhaust, 24lb injectors, and they emphasized PROM tuning. Im not shooting for that quick just yet, but low 13's would be nice to start with.

 

I'm running almost the same setup expect I have a 2.59 gear and 2151 Hooker 3/4 fl headers with 3 inch y pipe and a flowmaster catback systems in a 86 vette.
I had to replcae the fuel pump it was not holding pressure at WOT in gear (revving it in park it would do fine) it would drop down to 20 psi from 38 at idle ~45 with no vacum on the fuel regulator (holley adjustable). I reprogammed the eprom for 24.00 injectors and adjusted the timing to 12 btdc at the distibutor for now and left the eprom timing alone. No track testing but its seems to be getting close to what you would expect. Before the fuel pump it was slower than when I had the stock 130000 mile l98 in it.

 

Must have had some serious heads on it ...to make it do that . Especially with TPI on top . That would make it no where near even close to stock ZZ4 . Actualy Its not a ZZ4 ... the cam is gone ....and so are the heads on it ( guessing based on that wicked time ) . Can you dig it up again ( what date ) ....I would like to read it . The ZZ4 with the TPI on it ....will be a mid 13 second car ...with optimised gears and prom tuneing imho .


With what I am running I expect no more than a 13.8 with mine . Sure I dont have the aluminum heads but I got a better intake , etc .