Has anyone had any good luck adding mods like Cam, Springs, Rockers, Larger TBI, Intake, headers and so on, but left the stock swirl port heads on the truck and just added better parts ie: springs, rockers ect.?

I'm in a performance bind, I have enough money to add a good cam, lifters, springs, timing set, 1.6 roller rockers, underdrive pullies, and a good intake manifold. I don't have enough cash right now for a good set of heads.

I've heard the Swirl Port heads are ok to 5500 rpm but fall off the chart after that. I've gone as far as I can with a custom tune, exhaust, cold air intake, tranny mods, larger TBI and injectors, etc. But I'm still way to slow. I know the cam will help a ton.

So has anyone else built around the stock 88-95 swirlie heads and still made descent power?

 

i am sure many people have done it but why get new rockers? the ones from the factory are good enough so that should free up some extra money.....also you dont have to spend big bucks for heads, take your stockers and port them yourself and you should be good, wouldnt do much good to get a cam that pulls higher than 5500 if your heads dont flow good past that, make sure you match the two.......

 

The swirl heads are good for nothing but gas mileage. Intake airflow is awful with those heads. Unless your are a real good head porter and are willing to do a lot of work for free you're better off with a set of non swirl stock heads. Try Alabama Cylinder Heads (Patriot's parent company) to see what deals they have on a pair of heads.

Good luck with your build.

Richard

 

Ok....lets see. What are you looking for? I built a ~300hp 383 TBI engine with them, exhaust port was ported and polished with a single pattern cam. However, if you did anything and you didn't have emissions checks, go for the heads and cam swap with a set of vortec heads and then a good cam for the 350 would be a 206/212 or something in that range. You will need a tune as well...TBI engines are sometimes a pain to tune for with a cam. Once the heads and cam is on, then at a later date, add the roller rockers....just a thought on that one. But I agree with Richard....after owning a set of AFR heads, if you want to make power out of a TBI engine, you have to get a set of heads.

 

I had swirl port heads on a 350 tbi i built a while back. I swapped them out for a pair of 350 tpi heads from a camaro and it made quite a big difference. I picked them up for $50 so you don't have to spend alot on heads.

 

So the TPI Camaro heads will bolt right on? Do you know what year the heads were off of, part numbers are any info. If that works that would be awsume! I could swing maybe $100 on heads but not any more, right now. Thanks.

 

Yea, heads from a 87-92 camaro would work. If you get the L98 heads, its nothing more then the heads they use on the zz4s. However, they usually sell those for about $150 or so. They are also aluminium, flow decent, and have 58cc combustion chambers so you compression would go from 8.3:1 to 10:1 roughly. Pre-87 and you have a different bolt pattern which would mean different intake.

 

Your best bet is to go with the vortec heads. I think they are about $600 a set maybe cheaper used. They're worth 30hp alone. I built a 383 tbi with the swirl heads. It had ridiculous tourque but laid down at 5k. I'd say either get them now, or wait. The tpi heads aren't enough different to really do that much. As for do it yourself porting, theres a little more to it than just hogging out the ports. The only do-it-yourself porting I recomend is gasket matching.

 

L98 heads flow surprising well...just under vortec heads. With vortec heads, once you pass .475 of lift, you will need to rework them with screw in studs from the press-in studs. The stock vortec springs are good too .450 lift. However, you will need the vortec manifold as well. So, your looking about $900 for the vortec conversion when you can get a Edelbrock TBI manifold for $240 and a set of L98 heads for $200 lets see and then with the other 460 bucks.....ported and polished, springs to match the cam, etc and bam...you have more power than vortec heads will supply. LPE has them flowing up there with the old AFR 180cc heads. So, it can be done but just find a good porter for the heads.

 

I guess I just need to find your head porting guy.