Hi everybody, I'm Garrett and I own a 94 f150 4X4 with a 6inch lift kit and 35x12.50 procomps Xterrains on 15x10 rims. The only real thing I done to the engine beside routine maintenance is put E3 spark plugs in and put a 3 inch exhaust pipe from the cat back to were the original exhaust dumped out.

My goal is to achieve as much torque within 1500-3000rpms as possible on regular pump gas while trying to stay under a $1000 per upgrade.

I'm looking into aftermarket heads but I'm not sure on what to look for in them to choose one over the other so any help on that would be greatly appreciated.
The Dart aluminum heads seem popular and are within the price range.

I also been planning on getting shorty headers for more low end torque but I read a couple post of people suggesting long tubes for more torque. Not sure if they were talking about the top end or not but that puzzled me a little.
The headers do need to be durable because I do take my truck in the mud.
I know summit makes a pair for real cheap but they are a thin gage tubing.

I do plan on port/polishing the new heads as well.

Cams are also another upgrade I plan on doing. I keep finding people suggesting crane for their products.

I will post links to the parts that I've been looking at tomorrow from my PC because right now I'm just using my phone.

 

What gearing does the truck have? It needs at least 4.56 and nothing else you do will have as much impact.

Best engine upgrade for low rpm power would be long tube headers and a 2.5" mendrel bent single exhaust system.

 

I have a similar situation, 86 F250 4x4 with a c6 and a 351w. I've gotten a Crane cam for brute torque, and a friend gave me a ported intake (dual plane), I have a Holley 80457 4bbl and am now trying to figure out what exhaust to get. So can we get a definitive answer on shorts vs longs for pulling power only and what else to finish the exhaust.

 

Longtubes are best for low rpm power with a moderately sized single exhaust to keep gas velocity high. Your motor would also benefit from a cylinder head change, late model E7TE or F1ZE or F3ZE GT40 heads would increase compression 1/2 to 3/4 of a point up to roughly 8.8 to 9.2:1 and in the case of the GT40 increase airflow potential 25% top 30%.

 

I'm no expert, at all. Not only does the Summit youtube show that shorts are better for bottom end torque than long, but this site also outlines why. Seems longs are better for the top end stuff, shorts for low.


https://www.sandersonheaders.com/lets-get-technical.html


"If you are using the engine in the 1,500 to 3,500 RPM range, which is typical for a street-driven vehicle, you definitely want 1-1/2" to 1-5/8" primary tubes for any small block and 1-3/4" to 1-7/8" for a big block engine. Any bigger and you will lose a considerable amount of low end torque. beyond 3,500 RPM it is a question of where you want the power peaks. As you can see from the charts on this page, small tube headers do not lose their edge in horsepower and torque until you exceed 5,500 RPM."


Seems pretty clear I guess, and I'm definitely not looking at high rpm, plus, fitment issues, so shorties would be the way to go, but, I will measure my stock manifolds and may end up sticking with them. All I want is pulling power, not racing top end.

 

Your quote talks about tube diameter not tube length, are you confusing the two parameters? And the graph on the link starts at 3000rpm which is solidly into the midrange for these engines so I don't know that it's relative either.

Short tube headers produce biggest gains at midrange rpms, if your motor makes power out to 6500rpm then maybe 4000rpm can be considered midrange but that is peak HP territory for one of these truck motors. Longtubes do produce more gains at higher rpms than short tubes but they also do the same at very low rpms and it's those gains that are useful in these trucks.

Here's a dyno graph from a 5.0 Mustang article comparing the two header types..

 

You're right about the 3000 rpm, I blew right by that. I said I wanted low end power for pulling only. For low end to mid, shorts seem to be the way to go, agree?

 

AAAAAnd, this article seems to say longs are better all around than shorts or stock, shockingly better...(so confusing!)


Manifolds Vs. Headers - Mopar Muscle Magazine

 

The thing is that any header on a 5.8L will help performance. The stock cast iron manifolds are a cork on a 5.0L and they are the same or worse on the 5.8L.

 

Compared to manifolds any header is better but for the rpm range where most street driven trucks operate longtubes produce the best gain

 

Best budget HP gains are from the used factory headers, Stainless, Short, Thick, online for 50 bucks. You really won't notice any difference on or off road, with or without trailer, at any RPM range you need to use.

 

He's got a 94 so it's already got E7TE heads

 

The choke point on his engine is the Thermactor bumps inside the exhaust ports. These can easily be removed with a porting bit, but the heads need to come off first to do it.