how much horsepower will i get alltogether if i add a header free flow exhaust a offy manifold and a edelbrock 500cfm is there anywhere i can find a used 4 bbl manifold

 

50 +/- 10...ebay, craigslist, classifieds...

 

If you watch the prices on ebay...you might as well get a new one (intake manifold)...Ive seen them exceed retail (in used condition...weirdest thing. I did see a DP go for a $100 local.

Jcwhitney, summit racing, jegs

 

Run it on a dyno before and after the mods and then you can tell us what the gains are.

 

I have the DP offy and the edelbrock, but I also have a cam, chevy lifters, shaved head and block, headers and dual straight pipes. I'd say by the feel it was well over 50 HP gain, more like a 100HP I thought, but that's "thought", do put it on a dyno for us will ya? It really just turned it into a different engine all together, it's more a like a hop'd up 302 now. My power band starts at about 2300-2500 rpms now and is still runnin strong at 5500. Pulling 10,000 lbs behind it as long as I kept it over 3 grand up the hills it would hold it's speed in 3rd and that's with 3.08's but I only got 3mpg, I think I'll stick with the Cummins for pullin the gooseneck, 16mpg is a lot better and you never have to shift outta 5th.

 

this is my first truck and i am just finishing check out my gallery tell me what you think when i get the mods though ill dyno it for ya

 

Much of the gain is locked up in poor head flowing characteristics which will nullify some of the gain from your projected mods. Have the head ported/polished along with port matching with the manifolds to get the most benefit from your mods.

 

Harte3 is right there. Diffintly do something to that head while you got it apart, I came by another head, so I think I'll port that one, bigger valves, etc. so I can keep driving my truck in the meantime. Then I can just switch em in a couple hours and be back on the road.

 

You'll only wish to do MINIMAL P&P, because if you do to much, you defeat the purpass of doing it in the 1st place.

 

What Flashy said...the object is to improve flow characteristics which can be defeated by "hogging out".

 

I've pretty much lost my low end so I'm gonna shoot to improve my high-end even more with opening up te head, if it turns out bad I'll put the old head back on, but you never know unless you try. I agree w/ what your saying though, you can't go to much on an engine that doesn't make much power after 5 grand no matter what you do. You'll diffently defeat the purpose.