Stepped Headers
 

I would like to get your guy's opinion on stepped headers. We are in the market for a new set of headers and was considering a set of Stahl's. The interesting statement that Stahl makes on their website is they feel that stepped headers are really not cost effective for any type of racing. They stated at best, you will gain 1% HP. That is the best case scenario. Stahl has been around a long time and I would tend to trust what thay say. I also would think they have a lot of dyno test data to back that statement up.
Anyone out there know any different?

Re: Stepped Headers
 

There are two schools of thought regarding stepped and non-stepped headers. Stahl makes a great header, and they also make stepped headers. Nevertheless, when you look around the pits at the fast cars in many classes, they are running stepped headers. From a technical standpoint, a properly designed stepped header, is the only way to go.

Re: Stepped Headers
 

The hard part, at least for me, is that this seems to be a "mystery science". Jetting, timing, etc. needs to be calibrated for the maximum gain that the header can provide.

You may or may not see a gain in et by dropping $1K+ on the stepped headers. I can't afford to do R&D at that price.

Don't get me wrong, I would if I had the extra money. It is hard to justify though. If you see .03 or .04 gain, was it worth it? Not to me, but that may well be why I don't have a car that runs 1.0 under-LOL!

I have to talked to a few header manufacturers about my combo, and none of them seemed to be very optimistic about any possible .10 gain in et, which is how much I would need to gain to justify the high cost.

Just my thoughts.

Jeff
6990 SS/MA

Re: Stepped Headers
 

Go to:

http://www.headerdesign.com

Become a member and you will have access to calculators and lots of information on header design.

Re: Stepped Headers
 

Talk to Calvin Elston (704.821.4494 Calvin@elstonheaders.com) about headers, both stepped and Tri-Y. In our SBC there was a .13 gain with no other changes. We never dynoed the SBC headers as they would not fit on the dyno. However, the BBC showed an AVERAGE increase from Stahl heades of 14 HP, 13 ftlbs tq from 6000-7500 on a DTS dyno.

Bill

Re: Stepped Headers
 

Bill, the 14HP and 13 Ft/lb torque numbers you stated were what percentage of your base horsepower? Those numbers are impressive. Thanks for the information.

Re: Stepped Headers
 

njk53 that comes out between 2-3 % Gain.

Re: Stepped Headers
 

We were on the dyno today testing exactly this subject. We tried our regular stepped Hedman headers with two different merge collector sizes, also tried primary length short and long. We had an old set of Bill Thomas 2" race headers with long collectors we bolted on to see what would happen. To our surprise, the old 2" headers produced more hp and torque from 6500-7200, however overall from 5000-6500 there was a decrease that more than offset the top end improvement. Our feeling was that the step headers were better, but we never tested the 2" headers with longer primaries or with the merge collectors so I suppose more work would need to be done to try and really answer the question definitively. The sizes would not permit swapping primary extensions or collectors, that might have narrowed the gap, or even eliminated it. We were doing other work so went no further with the headers at this time, but thought it was interesting.
BTW, we run a 396 oval port in stock eliminator.....

Re: Stepped Headers
 

Grant, we are going top run a 402 Big block in stock eliminator. The car currently has a set of 2 1/8 Hookers and the previous owner of the car dyno'd the motor with these headers and the engine builder said the HP/Torque numbers were very good based on what he has experience in the past. If you ever test the 2" with the longer primary, let me know the results. By the way, what did Hedman charge you for the stepped headers?

Re: Stepped Headers
 

this guy is in indy make a very nice product www.thefabshopheaders.com