MyFirst90coupe

Do they have the smog stuff on them? I'm thinking about getting a set for my L98 but all the ones on that auction site have smog tubes which I don't need. Just curious if they offer a no-smog option

93VettePilot

They come with smog hookups and don't offer smogless as far as I know.

93VettePilot

Update: After doing some tuning on the car there is new found power in all rpm ranges. Top end has a dramatic increase in power. Keep in mind that I went from factory manifolds and cats to long tubes and straight through bullet cats. For tuning purposes I had to add fuel at the upper rpms. This tells me that air flow through the motor(Volumetric Efficiency) has increased.

pologreen1

Sure beats the hell out of paying $1200 for just a set of headers. Good find keep is updated on the quality.

CAJUN C4

And they work with AFR L98 Heads.

93VettePilot

Great. Did you install a set too?

Strick

Just a note, I found that 1" stainless allen, socket head, header bolts are much easier to use rather than 6 or 12 point header bolts. Using a torque wrench is even easier even on ole #8.

CAJUN C4

I'm going to very shortly. Great info here. I'll be ordering a set within the next few weeks.

C4fan

Great write up, what a deal on the OBX headers too. Way cheaper than what I paid and I thought I got a good deal.

Soon2Bcammed

This looks great.. even though they are smaller primaries I think I would still see some good results with my Hot Cam.

Thanks for being a guinea pig and trying these out. They look pretty good !! Looks like I'll be saving my pennies

Rocket-J

Years ago I built custom headers for a Lamborgini speed shop. We had a computer program design that would tell me what size to make for the specific engine. It asked cubic inch, rpm and type of fuel. This progarm was designed by the late Jim Fueling, from Southern California. He is the one who designed the 3 valve head for the Ford Triton Engine.
Any way, his theory was to make the first part of the header pipe smaller to accelerate the hot gasses beyond the speed of sound for better scavenging. He then added an anti revesion chamber and then on to the collector. This method is use by some Nascar teams such as Robert Yates.
Bigger is not alway better, but design is.

Rocket-J

I just put a set of 1 5/8" shorties on my 383 and jump from 342RWHP to 366 RWHP. The new tune had to increase my af to 12.7.
I was told it was a waist of time but I am happy.. Nice increase for little money and Cal. legal.
Mine are not OBX. I am not here to steel the thread. Just saying 1 5/8" will work.
My cnc heads flow: AFR heads flow:
Int. at .600"= 276 w/1.94" Int. at .600= 262
Exh.at .600"= 182 W/1.5" Exh.at .600= 194

Just to compare with what ever size heads you have.

girvin02

93VettePilot, thank you for this informative writeup. I purchased a set, probably from the same seller, for a best-offer price of $450 (+ $45 shipping). I also kept the stock exhaust from the resonator back. The sound is now much more throaty and it is much louder at WOT - I love it. This is without a doubt the best bang for the buck mod I have made. I took the car to the track today and was amazed at the improved performance. My previous best 1/4 mile time was 13.824 @ 99.59 MPH. With no other changes but the headers, today I ran a new best of 13.399 @ 103.70 MPH. That's a serious horsepower increase for an investment of $495. Thanks again!

CAJUN C4

Ordered Yesterday from Racing Parts Depot for $475.00 + $45.00 Shipping.
Scheduled to arrive this Thursday.

dogfish246

AWESOME thread!!! OP thats great! I always wondered if these headers were good... Im tempted now and gotta start saving up cash after I buy books for school lol... THANKS A LOT!!!!!

cadmaniac

One quick question...I'm curious as to how it effects under hood temps compared to ceramic coated headers...Anybody know the answer to that?

Stainless vs. Ceramic coated.


I've got a set of cheap hedmens on my '86 driver and a set of TPIS ceramic coated and there is a big difference...So I'm curious....

dogfish246

Were the exhaust ports on the header round like in the picture?

CAJUN C4

Yes they are.I believe 1.5"

BucfanTitan

I know this is an older post. But are the OBX headers still decent. right now they have name your price on fleabay. Just wanting to make sure. Is this a project a novice could tackle or should this be done by a pro?

Ron B C4

Old post but curious if you are still happy with the OBX headers?