Equal Length Long tube headers
Thread Starter
Senior Member
Posts like a Northstar
Joined: Feb 2009
Posts: 789
Likes: 0
From: Northern Illinois

I found a guy in ebay making custom ones and I messaged him. It'* been a while though.
What I'm getting at is.. You can model equal length long tubes fairly easily. But, how do you know the bend radii you used when modeling is available for the given bends? There'* a small window when it comes to available bend radii.
I'm assuming you aren't going to have custom bends made due to cost and I'm also assuming that you're intending to use separate sections and weld them together since mandrel bending machines can only make 2 bends tops per section of pipe.
Also, I know it was a quick render but it looks like the plane the header flange is on is orthogonal to the exit plane of the collector. This would have the collector pointing up at an angle.
What I'm getting at is.. You can model equal length long tubes fairly easily. But, how do you know the bend radii you used when modeling is available for the given bends? There'* a small window when it comes to available bend radii.
I'm assuming you aren't going to have custom bends made due to cost and I'm also assuming that you're intending to use separate sections and weld them together since mandrel bending machines can only make 2 bends tops per section of pipe.
Also, I know it was a quick render but it looks like the plane the header flange is on is orthogonal to the exit plane of the collector. This would have the collector pointing up at an angle.

Hey I Found this, DIY merge collectors for less than $75.
Kind of off topic alittle bit but I chopped some 3800 series 2 headers from slp to fit my series 1, maybe this is an easy task if some one was looking for some thing quick and is not an engineering student
You don't have to be an engineer or an engineering student to make equal length long tube headers.
From my experience of doing a rough model in cad and actually making a log manifold turbo setup out of SH10 pipe, I realized that it'* much easier and more practical to take a few measurements and just do it. There is too much human error when cutting, welding, the metal deforming when welding, etc. to account for in a model.
So, for my long tube headers, I got an empty block, trans case, top end, and took a few measurements of surrounding components in the engine bay. There'* no suprises there. And I don't have a need for modeling it in FE software since I found my desired dimensions analytically.
From my experience of doing a rough model in cad and actually making a log manifold turbo setup out of SH10 pipe, I realized that it'* much easier and more practical to take a few measurements and just do it. There is too much human error when cutting, welding, the metal deforming when welding, etc. to account for in a model.
So, for my long tube headers, I got an empty block, trans case, top end, and took a few measurements of surrounding components in the engine bay. There'* no suprises there. And I don't have a need for modeling it in FE software since I found my desired dimensions analytically.
The car is a 98 Regal GS.
The intake manifolds are from a 3800 F-body. It'* a very common swap on other forums.
IIRC 97-98 are the target years as they have a inlet that points toward the battery (vs. straight) and a drive by cable TB. After 99, they swithed to a drive by wire TB and the inlet points straight toward the wheel well.
The intake manifolds are from a 3800 F-body. It'* a very common swap on other forums.
IIRC 97-98 are the target years as they have a inlet that points toward the battery (vs. straight) and a drive by cable TB. After 99, they swithed to a drive by wire TB and the inlet points straight toward the wheel well.
Registered to this site after seeing this just to tell you I will be your first customer. This is AWESOME! I've wanted this to happen for as long as I can remember and it'* great to see someone with the talent actually doing it!
Thread Starter
Senior Member
Posts like a Northstar
Joined: Feb 2009
Posts: 789
Likes: 0
From: Northern Illinois

I'm still working on them, I am trying to get a N/A and a turbo version made, the N/A length goal is about 45" per tube, and the turbo ones will have to be near 19 inches or 15 inches depending on the final orientation of the crap in the back of the motor. . . .
I am going to be under the car this weekend taking more measurements, so I will start workin' on them and getting some more ideas up here in a week or so. . . .
In the mean time look at this pine elephant ----->
I am going to be under the car this weekend taking more measurements, so I will start workin' on them and getting some more ideas up here in a week or so. . . .
In the mean time look at this pine elephant ----->
Resonance isn't the only thing going on. Think of how much more overall contact/resistance the exhaust is going to have with 45" long primaries.
By the same token, there'* a reason why modern car manufacturers do not create tunnel ram intakes like this anymore:

But most modern car makers still do use resonance to boost an engines powerband(*).
By the same token, there'* a reason why modern car manufacturers do not create tunnel ram intakes like this anymore:

But most modern car makers still do use resonance to boost an engines powerband(*).



