So I have a 1991 Z/28 and I'm looking for some cheap mods. Like so far I put a foil that directs the air intake and adds like 5-10 horsepower. And It has a miss, so if it is the injectors I will be putting bigger ones in and a chip. But that is all I can think of.

Any other cheap mods you guys could possibly recommend me?

Thanks

 

Go through the ignition system. Getting the motor in top shape and proper tune is essential for top performance. With the 1LE set up you've got the highest factory flowing exhaust system. Headers, high flow cats, and a cat-back exhaust aren't cheap but, are good boltons that boost performance too.

Cutting out the baffles in the air box is another cheap mod that will make a ram air set up. Cut out the baffles below the factory air box and attach some hvac ducting to it and run it behind the fog lights. You can also take out your fog lights for more airflow if you want.

When my car had the stock TPI set up from idle to 3,500 rpm the motor breathed a little easier. It also helped breathing in the 4,500 rpm - 5,500 rpm range. It's not a drastic difference but as you make more mods getting more air efficiently in and out of the engine starts to pay dividends.

 

The air foil will do little to none to help. DO NOT go to bigger injectors without retuning the ecm/prom to work with bigger injectors. That will only hurt it. At this point the 19lb injectors in your 305 is enough injector.


If you have a miss, troubleshoot the miss. Also yaj's advice is sound and experienced.