Headers on a Vortec 350...

[sled_dog]

Anyone installed them? Did it create a noticeable power increase? I'm considering a set of Doug Thorley or Doug's Headers for my 1997 C2500 soon. I'd like to get a little more power out of her, since I believe at this point I'm going to end up keeping it instead of selling it. Figuring on an air intake, headers, fix the injector problem that is making it run rich, custom program, roller rockers, and maybe, just maybe a cam.

 

[79k20350]

well if your goin to be into it enough to do lifters, you might as well do cam... as for the headers they cant hurt... but im not sure how much its going to help running a stock cat. your increasing flow with the headers and then its still being backed up by the more restrictive cat. if your going to run headers then id redo the exhaust with a good highflow cat, and some good mufflers. SHould sond great too with a good intake, tune, cam, lifter, headers, and exhaust you should get the thing breathing real well and should definetly pick up some power.

 

[sled_dog]

you ever seen under a Vortec truck? its factory twin 2.5" exhaust tube through 2, not extremely restrictive cats to a single muffler and tailpipe. I am going to put an exhaust on too, probably first actually, but I may well leave the stock cats. Replace them I may as well redo the entire exhaust brand new, and with the 4 O2 sensors that are in it....

not doing lifters, I said rockers. Vortecs have factory roller cams and lifters.

 

[79k20350]

i never looked under a vortec truck so im just going on standard reasoning. Gotcha on the lifters... read it too quick. i was wondering why youd switch um anyways (thought maybe they needed to be replaced), i know that the vortecs have roller lifter (like the lt1's)

 

[sled_dog]

need to think about it, got in the truck this morning, fired it up, put it in reverse, hit the gas, knock knock knock knock knock.... so now its got a good cold knock. Oil pressure is fine, I've heard it before but this was the worst its been. Guess I'll get another block and put together a motor to swap out some weekend.

 

[sweetk30]

first just try chopping off the muffler and go free flow somthing. i did just that and wow. felt some.