OK, '89 RS Camaro 305 TBI / 700 R4. The engine is mostly stock, only engine mods are March Powertech pulleys(2 piece) and a Open element K&N filter, Hypertech fan switch and thermostat.

I want to swapout the heads and intake.

I was wanting to bolt on an Edelbrock performer intake, and also I picked up a set of stock 416 heads. These heads came stock on 305 TPI engines right??????

Would these even make enough difference to mess with, and would I have to change the stock PROM tune?

Things I should watch out for?

 

What other mods do you have? You should really consider a full exhaust from the headers back before you do any other mod. Those mods are needed to support all others. A direct 416 head swap isn't worth it unless it is ported. Check out the stickies above (TPI vs TBI head flow).

 

I do have a high flow cat, 3" exhaust, and a Magnaflow muffler. I would be installing headers also.

 

If that is the case you next mod should be chip work. From there I would look into a cam swap and fueling upgrades. The stock heads can support nearly 300hp (Per dewey's results) so there isn't really a need to swap them yet. Even when that time comes you would want to port the heads. Whether that be your stock 187's or the 416's. The two heads flow almost the same in stock form and it isn't worth the effort of a head swap unless they are ported.

 

Also note the 416s will need the pre 87 intake. Wasn't sure if you knew.

 

Alright, so say I don't swap heads right now, What would be a good cam that I could install? Lift will give me high rpm power and duration is the low end power, or do I have it backwards? and I have no equipment to do the DIY PROM at home, so whats I good option here? Also, thinking of swaping to TPI later.

 

*usually* the higher duration the more high rpm oriented it is. Go with a cam in the 200-220 duration for a mild street build on that motor imo.

Go with lift around the maximum for stock heads (460-480). That's at the rockers btw. If you go any bigger than that you will have to have the valve guides cut down.

As for a cam swap any cam you swap in will need major tuning from what i've seen and heard.

Although if you're looking for a reccomendation i'd email comp cams and see what they think, they will probably email you a reccomendation for a comp cams xfi cam with similar lift and duration to a comp xe262.

 

I have the exact set up your talking about (check out sig). Heads and intake. It is NOT a direct bolt on. Keep that in mind. If I were you I would either get some 081 heads or use the 416 heads with a carb intake with an TBI adapter. That may require some work on the throttle cable and cruise control cable. They may be too short with the TBI adapter.