Stepped Headers

Grant Eldridge · 01-06-2008, 02:34 AM

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.....

njk53 · 01-07-2008, 10:33 AM

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?

Scotty D · 01-07-2008, 08:34 PM

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

Grant Eldridge · 01-08-2008, 12:43 AM

njk53,
My race partner custom ordered the Hedman step headers about 3 years ago, my understanding was at the time they were around $1000. and came with a conventional slip on collector. We later made up a set of primary pipe extension tubes, and then last year bought the two sets of merge collectors used to cobble together the present setup. Last winter we had the whole thing ceramic coated so the cost has now gotten up there, but they are working well. I had always wondered if 1 7/8/ to 2" might have been more suitable for the oval port motor, but have never looked into the computer modelling available.
I doubt we'll soon be re-testing anything as we lost a Schubeck on the final pull. Hard to know yet if we'll race his year depending on the extent of the damage....
Grant

01-06-2008, 02:34 AM	#1
Grant Eldridge Member Join Date: Jul 2007 Posts: 124 Likes: 0 Liked 0 Times in 0 Posts	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.....

01-07-2008, 10:33 AM	#2
njk53 Senior Member Join Date: Jul 2007 Location: East China, MI Posts: 504 Likes: 0 Liked 0 Times in 0 Posts	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?

01-07-2008, 08:34 PM	#3
Scotty D Member Join Date: Nov 2007 Posts: 139 Likes: 0 Liked 0 Times in 0 Posts	Re: Stepped Headers this guy is in indy make a very nice product www.thefabshopheaders.com Last edited by Scotty D; 01-07-2008 at 08:40 PM.

01-08-2008, 12:43 AM	#4
Grant Eldridge Member Join Date: Jul 2007 Posts: 124 Likes: 0 Liked 0 Times in 0 Posts	Re: Stepped Headers njk53, My race partner custom ordered the Hedman step headers about 3 years ago, my understanding was at the time they were around $1000. and came with a conventional slip on collector. We later made up a set of primary pipe extension tubes, and then last year bought the two sets of merge collectors used to cobble together the present setup. Last winter we had the whole thing ceramic coated so the cost has now gotten up there, but they are working well. I had always wondered if 1 7/8/ to 2" might have been more suitable for the oval port motor, but have never looked into the computer modelling available. I doubt we'll soon be re-testing anything as we lost a Schubeck on the final pull. Hard to know yet if we'll race his year depending on the extent of the damage.... Grant