I looking into a new cam for my 92 GTA. It has the LB9.

I've heard either the 92 Y LT-1 cam or the ZZ4 cam are good choices for a TPI 305. The only mods to the motor I have is the SLP Package (details in my sig) and I don't plan any more aside from the cam, new valve springs, and some rockers.

Which cam do you guys suggest and what springs and rockers shuold I use to get the most out of it? I'm not worried about CA smog, I just want the best combo for my motor that will give me the most power.

Thanks!

BTW, I'm also installing 3.42's so that should help the power band allot more than my current 2.73's...

Also, what do you guys think about a bigger Throttle Body and with all of this would I need a Fuel Pressure Regulator and/or bigger injectors? How will my SLP chip react? I don't want to have to change my chip...

 

Well reading through old posts I've decided to go with the LT1 cam. What year LT1 cam is the best and what are the exact specs on the best LT1 cam?

What rockers and springs should I go with? What about the bigger TB, fuel issues, and my SLP chip?

 

I've found some good 1.6 rockers, Comp Cams P/N CCA-1418-16 and valve springs, Comp Cams P/N CCA-986-16

How do those look?

 

...in regards to what cam, you may want to look a little closer at the ZZ4 cam. If you plan to do nothing else with your motor the best bang for your buck may lie in the ZZ4. It depends alot on what you might do to the motor later on. If you have intentions of base and head replacement or base and head porting the LT1 cam may give a bit more on the very upper limits of top end RPM, but that being said why would you want an LT1 cam in your motor then when other cams will be so far ahead in potential?? The ZZ4 cam makes a good combo of torque and horsepower. It also accepts the 1.5rr set up which you have. Easier and more econimical. I can hear people chiming in right now telling you to go for a monster of a cam, but truth be told the ZZ4 is a very friendly cam to pop in your GTA.

 

Well I have a problem of my valves floating anyway so I'd like to go with 1.6's and new springs anyway. I do plan on doing all the porting and polishing on my intake system but not for a while. Yeah I do not want a big cam that is more than what I need that's why it would be either the ZZ4 or the LT1, I was considering the LT4 Hot cam but I read it was too much for 305's.

 

Well I just ran the ZZ4 cam in Dyno2000 and it only gave me about 5 more HP and 50 less TQ That's not good at all. It helped my powerband allot but it doesn't yeild nearly the results I was hoping for. The LT4 cam did better in that it only caused me to loose 30 on the TQ but it also only gave me a gain of 5 HP.

Does anyone have a Dyno2000 file for the LT1 cam?

 

I just ran the Iterator in my Dyno2000 using the largest possible variations my engine can handle and not matter the most I can gain is 5HP and that means loosing 30 FT/LBS of TQ. The best one it came up with was a cam almost identicle to the ZZ4.

It looks like I'm not even going to bother with a cam swap, too much time/$$ for too little gain.