Ive got a pretty cool parts manager and he told me not to waste money on headers cause almost all of them will have no gain because the z already has well designed headers maybe another companys would work better idk

 

+1 trillion. Slap on a pair of test pipes then you'll have the biggest smile on your face.

 

Only true on the 07 HR motor. The 03-06 engines do benefit from headers, but not all designs. Crawfords will definitely gain lots of power with test pipes.

 

I highly doubt that test pipes will yield the results that he expected from the Crawford headers. If anything, me might gain 2-3 hp over the HFC complementing the headers.

I would still be really disappointed, especially considering how much money he spent.

.

 

Damn, this sucks!!!!Im not getting headers for sure now.

 

Headers need to be paired with a good set of cams to see a lot of gains. Whoever said you maxed out your exhaust flow is right. Work on the intake. Port the manifold, big bore throttle body and a spacer will help a lot. Cams will give you the most.

 

The cats might even be clogged a bit. You just never know with cats. Test pipes FTW!

This is the only dyno i've seen of a set of crawford headers not gaining anything.

 

He's got a crawford V5 which is basically like a spacer and upper manifold as a one-piece unit.

I agree cams will yield more power.

 

I didnt read that. You can try to switch to a full length CAI as well and port the intake manifold.

 

No = I would be pissed!!!!

 

I do have a crawford plenum already, and I should note that my cats are gutted, so they are effectively test pipes. Someone told me the gutted cats might not be tuned right since they weren't designed to be gutted, so maybe this is a factor.

Also I just want to say that my point with this thread is not to say that crawford headers don't ever produce power gains. The reason I posted is hopefully folks will have some suggestions or ideas on something I should do to get the gains from the headers. If the headers only produce gains with cams, I wouldn't have installed them, and I think crawfordZ would be up front about that.

In the end, if I can't get any gains from the headers, I'm inclined to remove them and put the stock manifolds back on. The headers increase the engine bay temperatures noticably (I can feel it through my seat, and on the floorboard), and if the extra heat isn't getting me anything, I'm better off removing them. It was an expensive experiment, but live and learn right

 

Yep.. Thats pretty ****ed up..

 

port the intake and get rid of the gutted cats they act like an expansion chamber causing reversion and probably negating any gains from the headers.

 

Interesting, isnt this like the first independent test of the crawford headers? Werent all the supposedly huge gains on Crawford cars?

 

WOW
Great read, and good info on this.
Sorry to hear about your results with those headers....

I was under the impression Crawford's made GREAT power...
Thanks for letting us know.

I do agree you should throw some Testpipes on there though.. Best bang for the buck on the Z's..

 

Isn't 255whp kinda low for a full bolt on 03' Z with a tune? Have you checked the compression in all 6 cylinders? How many miles does the engine have?

 

Some people with bolt-ons+tune get similar numbers..

 

The AF looks to lean on the 2nd one..Add more fuel and more timing

 

On a dynojet with crawford headers, intake, manifold, gutted HFC's, full exhaust, and a tune? Something is up.

Did anyone check to see if there was any knock? Was 91 octane being used? Something is up.

 

Like Arin said, this is the first I have seen Crawfords yeild no gains. Something is up somewhere, maybe the sky... Check around. Who did the tune again?

Chris