Header tube length
Discussion
I'm replacing the headers on my car. The new ones are slightly shorter than the old ones .
Will this make a difference?
The tubes on the new headers are the the same length, I know that having same length tubes is important but is being shorter than the ones they are replacing a factor in the engine performance?
Will this make a difference?
The tubes on the new headers are the the same length, I know that having same length tubes is important but is being shorter than the ones they are replacing a factor in the engine performance?
There's no optimal length, different lengths will have a different amount of impact over a different area of the power curve.
Longer is typically better for low down torque, shorter better for higher rpm (higher as in over 6,000 say).
As I fortunately know what you had and what you've gone to, I'd be happy to suggest it'll make the square root of f
k all noticeable difference and I wouldn't get hung up on it. Them being all equal length is also better than not, but again, will make no noticeable difference, as far as I recall you aren't chasing every single last fraction of a horsepower.
There's an interesting Engine Masters video whereby they quite literally hammered the st out of a new set of headers and it made fk all difference to the figures back to back on an engine dyno 
Have a look at the differences between header primary diameter, 1 5/8", 1 3/4", 1 7/8" etc., whether stepped headers are better etc. you'll find thousands of people arguing back and forth and providing their scientific explanations why each one is better depending on power level and what you're after etc.
By many accounts the collector length has far more impact, some say the tri-y style of header is better, it goes on and on.
Unlike the wife you probably won't notice a few inches difference in length basically
Longer is typically better for low down torque, shorter better for higher rpm (higher as in over 6,000 say).
As I fortunately know what you had and what you've gone to, I'd be happy to suggest it'll make the square root of f
k all noticeable difference and I wouldn't get hung up on it. Them being all equal length is also better than not, but again, will make no noticeable difference, as far as I recall you aren't chasing every single last fraction of a horsepower.There's an interesting Engine Masters video whereby they quite literally hammered the s
t out of a new set of headers and it made fk all difference to the figures back to back on an engine dyno Have a look at the differences between header primary diameter, 1 5/8", 1 3/4", 1 7/8" etc., whether stepped headers are better etc. you'll find thousands of people arguing back and forth and providing their scientific explanations why each one is better depending on power level and what you're after etc.
By many accounts the collector length has far more impact, some say the tri-y style of header is better, it goes on and on.
Unlike the wife you probably won't notice a few inches difference in length basically
Edited by SturdyHSV on Wednesday 13th January 10:39
Thanks James!
I was a bit concerned that I might have to get it remapped , the cost wasn't a worry but getting it to Carl and getting home and back was.
Also I didn't want to be driving around if the headers were going to make the engine run lean.It doesn't now if anything it's a bit rich.
I was a bit concerned that I might have to get it remapped , the cost wasn't a worry but getting it to Carl and getting home and back was.
Also I didn't want to be driving around if the headers were going to make the engine run lean.It doesn't now if anything it's a bit rich.
leigh1050 said:
I was a bit concerned that I might have to get it remapped , the cost wasn't a worry but getting it to Carl and getting home and back was.
Also I didn't want to be driving around if the headers were going to make the engine run lean.It doesn't now if anything it's a bit rich.
If you'd been bothered to write that in your first post you would have got a more accurate reply in the first place.Also I didn't want to be driving around if the headers were going to make the engine run lean.It doesn't now if anything it's a bit rich.
tapkaJohnD said:
Yeah, but the OP is on about exhausts, I think.OT but Dave Walker from Emerald has a great article online about inlet header lengths which they dyno tested - and as above, the longer they got, the better they got, even up to quite ridiculous lengths.
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