Best tubular manifold design

[MyBeatGSX]

I'm looking for some people with experiences using different styles of tubular manifolds (T3). It doesn't matter if you made 500hp on manifold A and someone else's car made 700hp on manifold B. I want to hear from someone that tried manifold A and then made 20hp more with manifold B, just because the design was improved. This is for comparisons only. We're trying to come up with a design to prototype on my car, and if it performs like I should, we'll be producing them.
The manifolds need to be streetable. I don't want to do a half size radiator and my turbo in the front bumper. They don't have to be stock location, but as long as a full size radiator and the PS pump can stay in place, then it's streetable.

And anyone else, feel free to post up pics of any DSM tubulars for ideas, just try to keep the original topic in mind. If you feel like designing something yourself, by all means go for it. If it looks good, we'll build it and add it to the dyno test.

 

[brute]

If you were to make a manifold, I'd need it to be very streetable, just as you said. To me, this includes being cast. I personally don't think tubulars have any business being daily driven, so I'm not going to be buying a tubular. I really like the Turbonetics design. I like how it's cast, and I like the wastegate provision.

 

[1stGenRocks]

i want someone to make a cast manifold with the wastegate flange off the collector instead of #1 runner

 

[thisdsm]

The best tubular manifold out there is the HKS. Although, the HKS is only t4, I am sure you guys can rig it up to a t3.

 

[MyBeatGSX]

i want someone to make a cast manifold with the wastegate flange off the collector instead of #1 runner

It will be. I'd never put a wastegate off a runner.

And brute, that's totally incorrect. People just use poor quality, thin tubing. We use very thick cast stainless bends. So technically, it is cast metal. Honda people have been running our manifolds for going on 2 years now with no issues. And this is with no bracing on large turbos. We have only had one instance of cracking and that was with an unbraced topmount manifold holding up an HX35, wastegate, and downpipe (on the shop car). The crack developed because of a welding defect that has since been corrected.

 

[MyBeatGSX]

The best tubular manifold out there is the HKS. Although, the HKS is only t4, I am sure you guys can rig it up to a t3.

Sounds interesting. Any links? I haven't come across that one yet.

 

[turbo2086]

Why don't you think tubular manifold has no business being street driven? Not concerning quality, you can find an ebay tubular manifold with a wastegate tapped on the collector. I like that design. What about a tubular manifold, but instead of the crazy bends, just make it straight out, like the cast?

 

[project_tsi]

If you were to make a manifold, I'd need it to be very streetable, just as you said. To me, this includes being cast. I personally don't think tubulars have any business being daily driven, so I'm not going to be buying a tubular. I really like the Turbonetics design. I like how it's cast, and I like the wastegate provision.

Derek, I have to kinda disagree. Its really got a lot to do with how it is made. Including what type is steel is used, thickness, welding design, backpurging, collector design, jet coatings etc, etc.

Most people don't realize how much goes into a well designed manifold, thats why
whenever I read a post from someone saying how so and so's manifold's price is rediculous I kinda get a laugh out of it. Anyone can weld some pipes together and call it a day, but try hanging a 30+ pound turbo off it, make sure the welds are not only strong but look kick ass, make sure it fit's into a fairly restricted amount of space, research materials and weld technique so it doesnt have heat related cracking issue's and then spend untold amount of hours researching exhaust theory, turbo theory, thermo dynamics and try to apply it in a package that actually fit's trying to achieve maximum hp and minimal spool up. It's enough to make your head spin .

Backpurging is basicly replacing the air on the inside of the pipe with a inert gas of some sort which allow's you to get a nice clean weld on the inside and nodeposit's (clumps of metal which build up on the inside of the pipe from the heat) which not only impede flow
but can break free and wind up in the turbo, not good.

Jet coated 321 stainless is an excellent choice in thin walled tubing, thats what magnus uses on their custom setup's. While the 321 is by all means the best as far as materials are concerened (unless you consider Inconel), the heavy duty schedule 10 (especially jet coated) in my personal opinion the best bet for a street/strip driven type vehicle, which is why it has become the standard for the turbo manifold aftermarket.

As far as the 304 stainless schedule 10 the wall thickness (around 3/8") makes the relative strength difference's between the different series not so much of an issue. The schedule 10 is kind of overkill itself and has been used for years with no real issue.

The 321 while a stronger, more heat resistant version of stainless, comes in a thin wall tubing, so it kinda evens the two out. This has been for the most part used
on drag cars (lighter and has some better thermal characteristics high end tuners like) so it's been a little more difficult to find information on it's daily driver reliability. I've had trouble finding long term daily driven cars that see those kind of heat cycles using the 321.

The 316ss is about in the middle of the two, being a very strong steel with very good heat properties, but also a thick wall tubing making it very strong and great for reliabilty and DD street use. This is what my manifold will be made out of with MC-15 jet hot coating.

Hope this helps, Dan.

 

[MyBeatGSX]

Why don't you think tubular manifold has no business being street driven? Not concerning quality, you can find an ebay tubular manifold with a wastegate tapped on the collector. I like that design. What about a tubular manifold, but instead of the crazy bends, just make it straight out, like the cast?

You mean something like this... http://www.ccfabonline.com/displayProductDocument.hg?productId=3&categoryId=4

That's already made and will be included in the dyno test. Any other ideas?

 

[DSM007]

The best tubular manifold out there is the HKS. Although, the HKS is only t4, I am sure you guys can rig it up to a t3.

Not to mention that there is only 300 of those manifolds here in the united states.

 

[Turbo Monk3y]

Not to mention that there is only 300 of those manifolds here in the united states.

originals, but copys there are hundreds more....

 

[Slow99x]

Best manifold for T3 or T4 style flange by many accounts is Shearer Fabrications. Not only can you get the predesigned manifolds found on their website but you can also get them welded for your particular application. Devo Tuning put together an Evo II with a Shearer manifold with the turbo mounted under the right front headlight. The turbo was a GT42R and was a twin wastegate design. Due to the lenght of the runners and weight of the turbo the supports went to the valve cover and strut tower and had a "floating" collector with springs to allow for some movement. I don't think anyone will be running a manifold like this for the street but I think that their street manifolds use the same steel tubing and collector design.

 

[Flash]

I have never thought of a manifold giving you increased horsepower numbers, but rather being a small part to a big equation.
I agree with Shearer Fab producing the best tubular manifold. I have yet to see a merge collector that is as perfect as Shearer's. You can stick two fingers in it and feel around and its smooth where ever you touch.

 

[PSI NRG]

Ron Shearer does amazing work I've seen a few of his manifolds and they are works of art. If I didnt already have the DNP and I had some extra cash I would be ordering one right now.