stupid long or shorter headers?

[WSSix]

In order to build headers that will clear everything on the car and not drag the ground, it appears I'm either going to have to go rather long with the primaries or go short. By long we're talking 40-42 inches and short would be maybe 24-30 inches at best. I know from my reading that the prevailing thoughts are longer primaries are better. I guess the question is are they really worth the effort? I'm leaning towards longer primaries just because I think it would be fun to build and look great. I'd also hope it would help make more power. I have no doubt they will be harder to construct than shorter headers. I don't have enough knowledge or experience to say if it's worth it though. Thoughts?

Thanks

[spode]

42" headers sound way to long. I think most are in the 28" to 34" range. The length is set for max power at a specific RPM based on cam, heads, intake, bore, stroke ect, ect. http://mez.co.uk/mezporting/exhaust_length.html
Make a set as best you can but I wouldn't sweet getting the length exact.
I know it can be just internet chatter but most people consider primary diameter more important then length.
http://ls1tech.com/forums/conversion...o-results.html
http://www.hotrod.com/how-to/engine/header-basics/
http://www.speedtalk.com/forum/viewt...hp?f=1&t=26079

[Rick D]

Originally Posted by WSSix

In order to build headers that will clear everything on the car and not drag the ground, it appears I'm either going to have to go rather long with the primaries or go short. By long we're talking 40-42 inches and short would be maybe 24-30 inches at best. I know from my reading that the prevailing thoughts are longer primaries are better. I guess the question is are they really worth the effort? I'm leaning towards longer primaries just because I think it would be fun to build and look great. I'd also hope it would help make more power. I have no doubt they will be harder to construct than shorter headers. I don't have enough knowledge or experience to say if it's worth it though. Thoughts?

Thanks

Trey,

How come you want to build a set of header? I would think for your combination there would be a lot of good choices for headers?

If it's just you want to build them yourself I get that?

As for question, I've worked with a lot of racers that have a lot of different opinions on headers, most alway it comes back to tube diameter is more important or at least looked at more closely then how long. After the tube size is selected then they build them equal length for the room they have in their chassis.

Way smarter guys on here then me on this subject so hopefully they will chime in?

[Vince@Meanstreets]

We tried several headers on an engine dyno and the difference was 8-10 HP but an increase in TQ between Patriot middies and Dyna tech full....that 8-10 HP loss was well worth the ground clearance we gained with the middies.

[WSSix]

Thanks for the replies you guys.

Rick, with all the choices for headers I've seen and am aware of I'm too low for off the shelf designs. As it stands, a typical stacked 4 into 1 collector would hang over an inch below the subframe and that's with the exhaust only 1/2" below the floor. Also, being a WS6 car causes a lot of issues with headers because of two small braces that tie the rearward lower control arm mount to the subframe. I could remove the braces as they are bolt in but they work from what I have read about these cars so I want to keep them. It would be a little easier if I didn't have half height solid bushings.

[carbuff]

Can you find, or build, a set of Tri-Y headers instead? With a 2x1 instead of 2x2 configuration under the floorpan, you should have lots of clearance. That's what I have on TOW, and after a bit of cutting to bring them up a little bit (about 1 inch), they are just about perfectly tucked...

[WSSix]

Bryan, I was originally wanting to do tri-y headers but have been talked out of it due to the sensitivity in getting the lengths correct. From what I've found it is critical and can rob power if done incorrectly. What I had decided on was to do "normal" long tubes with a tri-y merge collector with the collectors all laying flat instead of the first two being perpendicular to the final collector. That way, I only have 1-3/4" pipe to fit under the toe boards. From there, I would just go into 2.5" pipe which only hangs a little below the subframe, maybe 1/2". Tri-y's would definitely solve my issues if I could find someone willing to say what lengths I need with certainty that they would work and not choke the engine.

Cone said flat 4 into 1 collectors are not good. SPD has a 4 into 1 flat merge collector that may work but I still have to have really long primaries to get to where I can use that collector as well.

Basically, on the driver's side the clutch slave cylinder sticks out right where I was wanting to place the collector.

[Ron in SoCal]

Why did Cone say 4-into 1 is not good?

[WSSix]

The flat 4 collector isn't very good compared to a traditional stacked, stacked merge, or tri-y merge collector. The guy at Cone didn't elaborate as to why but I would guess it's a manner of flow velocity. Not sure what the guys at SPD think of their flat 4 merge collector though. I might shoot them an email. I'm still faced with the same problem using a flat 4 collector as a flat 4-2-1 collector arrangement though. If I go shorter on the primary tube lengths, I'll be able to use a stacked 4 into 1 merge collector.

[Flash68]

What's the approx power level here?