Building headers & need advise

[Greg from Aus]

Hi guys,
I'm building a set of headers and I want max ground clearance, can I bring the collectors up on the slope of the toe boards?
Please see the pictures for my idea's.

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[Ron Sutton]

Of course you can do it that way. Some headers are built that way from the company. But it does shorten your primary tube length signifcantly, which will affect the power curve of the engine.

Do you care?

If yes, how much does that shorten the primary tubes? What length primary tubes would you end up with?

While you're at it, provide us with the primary tube diameter, HP output of the engine & rpm range you expect to operate in.

[Sieg]

First time I've seen this desire.........how low do you need to go?
Manifolds and oval tubing?

[Flash68]

Looks like you are trying to build some shorties there.

Check out Stielow's thread.. he just posted some shorty type header pics for the added clearance he wanted I believe.

[dontlifttoshift]

Sure can. Like Ron said above it will affect peak power but it may not matter.

Here are the headers mentioned from Mark's current build http://ultimateheaders.com/bends.html

[Ron Sutton]

Actually, shortening the primaries will reduce low end & mid range torque & response.

If you get too short, it can mess up the soundwave harmonics of the exhaust & reduce power even in upper rpms.

Some people want to reduce bottom end, so it's they are not fighting for traction as much & reduce their tire spin. Other drivers want torque on the street ... because it's awesome ... as long as you have traction. And in his case, Tonner may "have to" to make everything fit.

Tonner, if your goal is to reduce torque ... and package the exhaust better ... my suggestion is work to keep the tubes all the same length, and a minimum of 27" long from the face of the head to the end of the tubes in your collector. This will move the power band up some (less bottom end & a little more top end).

If you have to go shorter than 27", the power penalties will start be larger, and potentially across the powerband.

If you have room to make them longer than 27", I'd be happy to help you work out the optimum size for your engine package. I would need some details to do so.

Best wishes.

[Greg from Aus]

Thanks guys,

I have a RHS tall deck in an Art Morrison frame with tony Wooward rack.
The engine is a 440, mast motorsport black label heads with a Ozmo twin throttle body manifold, it's has a solid roller cam, I'm not sure of the spec's.
Projected Hp is 700 - 720 at the flywheel.

I have been mocking op the headers today using the Icengineworks system, there is not a lot of room on the drivers side. The tube is 2", and the shortest pipe is 24" to the very front of the collector.

All help is greatly appreciated. :thumbsup:

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[Ron Sutton]

I have a RHS tall deck in an Art Morrison frame with tony Wooward rack.
The engine is a 440, mast motorsport black label heads with a Ozmo twin throttle body manifold, it's has a solid roller cam, I'm not sure of the spec's. Projected Hp is 700 - 720 at the flywheel.

Nice ! :thumbsup:



The tube is 2", and the shortest pipe is 24" to the very front of the collector.


You don't want to measure to the front of the collector. With your collector, the individual primary tubes continue on for a several inches inside the collector assembly.

Even though you bought a collector assembly ... technically, the collector doesn't start until the individual primary tubes stop.

So, measure your collector. Measure from the "front" where the primary tubes enter ... until the primary tubes inside the collector stop. You will see a point where all four primary tubes end inside the collector. That is where the primaries end & the collector starts.

You're going to add the lengths of the primary tubes you have built ... to the length of primary tube inside the collector. Don't forget to subtract any overlap where the collector assembly slides over the tubes. (Just so you have an accurate & true length.)

When you figure this out ... post again with the primary tube lengths.

Before, when I didn't know what you had for an engine ... I was "assuming" you had an LS or SBC putting out 450-550 hp. In that case, 27" primaries was my suggested minimum length.

Now, knowing more about the engine you have, I "think" your optimum primary length will be around 27". You could go a little shorter if you need. I say, I "think" because I don't have all of your engine info.

I'd be happy to help you work out the optimum header dimensions ... and optimum exhaust system for you, but you're going to need to provide me with a LOT of specific engine data. Just let me know.

[Ron in SoCal]

Hey Greg great pics, car is coming along beautifully. With my similar set up minus the Woodward rack, the passenger side is cake. The driver side is a different story. From your pics, it looks like your steering shaft mount location on the rack exaggerates this as well and forces the header mods? Same boat here...

My options are to either get a Borgeoon triple joint coming off the rack, or mod a tube (or both). I could also go to a multi-sectioned steering shaft, but that's not preferable.

[Greg from Aus]

Nice ! :thumbsup:




You don't want to measure to the front of the collector. With your collector, the individual primary tubes continue on for a several inches inside the collector assembly.

Even though you bought a collector assembly ... technically, the collector doesn't start until the individual primary tubes stop.

So, measure your collector. Measure from the "front" where the primary tubes enter ... until the primary tubes inside the collector stop. You will see a point where all four primary tubes end inside the collector. That is where the primaries end & the collector starts.

You're going to add the lengths of the primary tubes you have built ... to the length of primary tube inside the collector. Don't forget to subtract any overlap where the collector assembly slides over the tubes. (Just so you have an accurate & true length.)

When you figure this out ... post again with the primary tube lengths.

Before, when I didn't know what you had for an engine ... I was "assuming" you had an LS or SBC putting out 450-550 hp. In that case, 27" primaries was my suggested minimum length.

Now, knowing more about the engine you have, I "think" your optimum primary length will be around 27". You could go a little shorter if you need. I say, I "think" because I don't have all of your engine info.

I'd be happy to help you work out the optimum header dimensions ... and optimum exhaust system for you, but you're going to need to provide me with a LOT of specific engine data. Just let me know.

Thanks for the info Ron,
I re measured and it is 28".

I don't have all the engine specs as it's being built at the moment.

:thumbsup:

[Greg from Aus]

Hey Greg great pics, car is coming along beautifully. With my similar set up minus the Woodward rack, the passenger side is cake. The driver side is a different story. From your pics, it looks like your steering shaft mount location on the rack exaggerates this as well and forces the header mods? Same boat here...

My options are to either get a Borgeoon triple joint coming off the rack, or mod a tube (or both). I could also go to a multi-sectioned steering shaft, but that's not preferable.

Hey Ron,

Because mine is a tall deck block and the Woodward rack, there was nothing I could do but make a set, and I really am enjoying the challenge.

[Ron Sutton]

Thanks for the info Ron,
I re measured and it is 28".

I don't have all the engine specs as it's being built at the moment.

:thumbsup:

2" x 28" will be right in the ballpark for a engine like this making 700-720 HP.

Best wishes.