I have wanted to get into a camaro again ever since I sold my 79 Z28, that was over ten years ago. I owned 2 1970 camaros a 78 Z28 and 2 79 Z28’s. I had real problems with having my license taken away so I took my need for speed to the water where I play with a blown BBC 468 making over 900hp. I build ALL my own motors and can put a big block or a small block (small block It’s been a while) together in my sleep but I don’t have a clue about what to do about a 1991 5.7 Z28 I just bought that has a blown motor and trany. Can I use an older style motor, I want to build a 10 to 1 383 short block and use all the existing top end will this work or do I need a new style block, will the computer need to be messed with, will it pass smog if I use the the stock cam. I don’t even know what kind of trany is in this car. I thought it was a 700R but someone just told me that it may be something different. You guys seem to know your stuff, could you let me know what I sould do to get this thing to run and still pass smog Thanks. Any BBC questions I will be happy to answer.

 

Welcome aboard thirdgen.org, and back from the 2nd gen Dark Side. . .!

The easy things first: If it is the stock automatic transmission, it is a TH700R-4.

Now, about this TPI induction system: It chokes 305's. Imagine what it's doing to a 350, and what it would do to a 383. It hits the wall at 4500 RPMs, being "tuned" to produce a marketing-friendly seat-of-the-pants acceleration-from-the-stoplight feel. If you want to build a performance emissions-compatible package, it is possible, but you aren't going to use much of the stock equipement. And, in 1991, they used what is called a "speed density" computer system, which is good in one sense because it can be calibrated to handle much higher performance levels than the previous mass air flow, but bad because any change to the engine system that changes the assumptions made in the programming parameters requires reprogramming to accomodate them. Get comfortable with the concept of PROM burning hardware and software.

For the TPI equipment, start looking into things called base, runners, Big Mouth, ported plenum, Super Ram, Miniram, 58mm TB, etc. You can get it to pass smog with a much better than stock cam as well.