5mm wall thickness steampipe would have to be the hardiest rotary exhuast manifold material commonly used.

Cast manifolds are crap. Factory non turbo exhuast manifolds on production cars are cast, and they crack like there is no tomorrow and they dont even have 900 degrees or 20+ psi pressure to contend with.

The price i qouted on the SS manifold was for 321SS. $1000NZ is only $600ish USD when you convert it but to put things into prospective it'd be about $1000USD when you compare relative prices of other things

 

someone either here or on the other forum said that it IS the OBX piece. they tried to contact them and the response came from ssautochrome who sells the OBX.

i have it and it was not worth the headache. i had a spacer welded onto it, the holes on the flanges did not line up....notice i said flanges. as in all three.

while at gotham racing, scalliwag helped out with the modifications to get the thing on the motor. he had to cut off some the flange in order to clear the external case bolt (tension bolt) and enlarge the holes a little to clear the studs on the rotor housings.

he also had to screw in a bolt and grind it flat, then drill a NEW hole and tap it in the correct location for one of the wastegate bolts.

after all that, steve had to manipulate the bolt holes on my turbine housing(60-1) to line up with the manifold. i was picking hot metal shrapnel out of my forearms from holding it while he grinded away.

after all the work i have done and money that i have spent and respent because of stuff not working right, if this manifold cracks or if i have more problems, i'm selling it getting a Infiniti FX45

 

the best would be the RPS header(jet hot coated), then HKS.....

RPS header w/ HKS Ti/ w HKS GT wastegate w/ HKS Racing BOV..... there's no sound like it

 

I just love these generalizations...

I guess those HKS and XS Engineering units are crap too.
Funny, I have never seen any of them crack.


-Ted

 

ss manifolds are also known to sometimes make an anoying sound (angry bees in a can) but thats normal , i have ss and i had an hks cast, the cast is great for durability ,ss is good for performance ....youre preferance

 

Well for myself performance is important but not more so, than logevity. I'm not running a F1 team that doesn't care if the welds blow after 10k mi since they don't run manifolds for 2k mi.
For me though I'm willing to sacrifice some flow, to have something last 5-10 Years, since I like driving my car, not replacing parts every year or so...

My Vote goes to cast, I also understand that cast has better heat absobtion, and radiation properties, than stainless... but I might be missinformed.

 

Has anyone made a custom manifold using "Inconel" (sp?)???

I know a guy here with 20B engine made one for his car..

I'm wondering if its worth the money.. Also, I've recently met a guy who might be producing high quality 13B manifold for single.. He knows a guy who builds manifold, exhaust, etc for funny cars.. Apprently he has a bender that bends 12 bends before coming out..

 

that would be john aka 20b3rdgen , not shure if its worth the extra money but it shure looks cool

 

After what I have read so far, it seems like someone has been watching too much Fast and the Furious (blowing welds on the manifold?). Make sure your diamond plate floors are secured guys. Seriously, the material of the exhaust manifold should match the type of power you are trying to make. If you are going to run at high boost, then I suggest you consider a stainless header. If you are going low, then a cast manifold is your ticket. It might also be a good time to research each material (cast iron and stainless steel) to better understand what is going on. Cast iron offers less heat rejection (better insulation), but is not applicable for high boost cars because of it. Stainless steel is good for high boost cars (high heat rejection rate), but is brittle and may not stand the test of time compared to a cast iron. Also, remember that exhaust headers, or any other part will last forever as long as you treat your car right. Inconel (aka unobtanium) header? That is way too expensive, and not worth it, assuming your car's single turbo setup is for the street. Remember to consider what your application is. Good luck with your project . Education is the key .