So I'm having a hard time trying to figure out the best way to make more top end power out of my Camaro. The reason being is that I occasionally road course my car and I am in the higher end of my rpm a lot of the time. The car is an original 5 speed car with a stock rebuilt 350 tpi (from an auto car). The cars horsepower starts dropping off around 4200, and I would like to get it to pull to 5500 or even 6000.

So I was thinking of converting to a carb setup, maybe something like a rpm air gap with a 650 cfm carb with some nice headers? I was also thinking of maybe having the cam replaced, but don't you need to pull the whole engine apart and get new bearings? Lastly, the main reason I'm skeptical about keeping the tpi is I don't know much about reprogramming the ecu for new injectors for the possible demands of more fuel.

Just really looking for some suggestions on good routes to take.

 

This a bit vague and confusing are you looking for more top end power with TPI or changing set up completely. More info to you car might be helpful, as to mods if any.

 

Well the only mods on the car currently are:
- Screens removed off MAF
- MSD external coil
- Holley air foil
- K&N air filter
- Accel plug wires
- Removed A/C and smog system
- Gutted interior

Other than that it's a 1987 Camaro Iroc Z/28 5 speed with a rebuilt 350 (from an automatic Iroc car).

I would like to stick with the tpi setup because it's already on the car. But if switching to a carb setup with a good intake manifold would help my top rpm range, then I would not mind converting. Plus I'm better at changing jets and calibrating a carb then tuning an ecu and buying expensive injectors.

So basically I'm looking for recommendations on the simplest way to increase my rpm range, if that's a cam swap, head port, converting to a carb, or all of the above idk.

 

So I may have answered my own question, but I searched around a lot. And am curious as to what people think of a combination like this.

- Crane cams "Compu" 2032 - http://www.cranecams.com/88-89.pdf
- An rpm air gap intake manifold with a holly 600cfm double pumper (I'm in CO.)
- Street porting the stock heads and cleaning them up.

If I read the stuff right I searched around for, I should be able to run the stock valvetrain with that cam too. And should get a healthy pull up to 6000 rpm.

 

Your goals are inconsistent with your desires.

The TPI is not going to get your RPMs up. If the bottom end is good, you'll need a cam, heads, intake, and exhaust.

As to converting to carb, I don't see the point in going backwards.

As to current mods, removing the smog and AC did more for you than all that other stuff combined.

What's your budget? Start there.

 

Might want to look at other mods that will yield you more return on investment like exhaust, gears, and work from there. Full exhaust will be sure to wake up the car. To move up your power band you can get a set of slp runners and open them up

https://www.thirdgen.org/forums/tpi/...owing-tpi.html

 

My budget is around 500-700, I tend to source used parts so that can actually be a bit.

And I will definitely get some headers with a nice cat back, I think that will help me out a lot. But I'm still obsessed with hitting good hp at the 6000 rpm mark, and those slp runners do look like a good start. One of my concerns is hitting a cap with the tpi, since I read about how limited it is in the high rpm area. But that thread you linked looks like they're hitting the 6000 rpm mark very well.

 

for the amount of money you are trying to spend there is no possbile way you will make good power at 6000 rpm with tpi. (a modified tpi like some of the heavier modded setups on this forum are well in excess of 1000$ in just the intake setup) . As for your carb, intake and cam idea that will get you close ,but i think the stock exhaust would seriously choke your higher rpm capabilities at that end as well. For now i would say best return on investment would be mild port work clean up, cheap headers, and a cam the size you stated or 1 size larger even. That along with the intake you said and carb would make a decent mid range engine. still be super lucky to get by under 1k and have it hold together well. Also an airgap intake probably will have a rough time fitting under your hood (food for thought). not saying i condone going carb i like my efi but for your goal it would fit best.

 

https://www.thirdgen.org/forums/tp...owing-tpi.html (Quest for a better flowing TPI)
I agree after reading those threads. They put a lot into making the tpi flow efficiently to 6000 rpm. I think I can achieve what I'm looking for by going with the carb and intake setup I mentioned. And with the stock head porting and cam upgrade, that should give me enough mid and higher top end for now.

Well to solve that, I just got a set of hedman headers (500-68478) for free this morning, I just did some bike work in exchange. As well I got some nice valve covers he wasn't going to use. I should make a custom exhaust system to go with the headers, maybe just a nice dual 2.5 system with an x-pipe and high flow mufflers. (The wheels in the pic are some Torque Thrust II's I'm selling.)


That is true, I've made a lot of fiberglass body parts before, so I can try to make a lift off fiberglass cowl hood then. A bit time consuming, but making one off parts is always more unique.

Thank you everyone for all the input so far, more ideas the better. I think I might make a build thread for my car here soon.

 

You might be able to hack at the TPI enough to make 6000 rpm but it wont be making power or "pulling" up there.

Youre road racing that TPI is killing you, ditch it if youre going carbed put the rom air gap on, 600-650 dp youll be happier. That cam if you can, bump it up some. Work your heads, see if you can up your compression some too. Stock shortblock? cc size on piston, how far down the hole is it, chamber size of heads?

Wouldnt run old stock valvesprings up to 6k either springs for what youre doing are cheap.

 

The bottom end and heads are stock, not sure on the cc, but I will find that out when I pull them to port and polish. I can't wait to get the whole set up done now. I'll just have to be patient and source all the parts over time.

I was kind of thinking the stock valvetrain might not hold up either, I'll call Crane Cams and see what they recommend and then look for the best deal.

What are your thoughts on upgrading the harmonic balancer, since I'll be pushing the stock engine to higher rpm's. Reducing vibrations obviously should be a good thing, but will it reduce enough to be worth it?

 

Stock balancer can handle 6000 just fine.