Think I'm getting ready to send my shortblock out to get it built, just upgraded pistons/rods. FBO, thinking about S2 cams as well. I currently have a MHI 18K making 397/370 with stock SST. Would it be worth keeping the 18k with built bottom, no E85 so 93 octane only? Was looking at the stock upgrade 3576 or maybe 82. I'd love to hit closer to 500whp, full boost around 4500ish. Any opinions on the next step? I'm also researching 5558 or 7670. My SST has been solid so far, so not sure if I should send that out to Kozmic for clutch fork fix, upgraded clutchpacks just yet. Depending on total price I could just slap used shortblock in, sell and use cash for an RS3. Decisions.....

 

If you want to hit 500whp on pumpgas, the non stock frame turbos will be an advantage. The 5558 would do it no problem. Gen 2 3076 stock frame might get you close without being laggy like the 35's

 

Thank you, I'll set my eyes on 5558. Not much info but sheets I saw seemed pretty good.

 

The problem is "non stock frame" now = tubular welded manifold. Which is not IF it will crack but WHEN it will crack. AMS and MAP no longer sell the beautiful cast v-band manifold that allowed just about any sexy turbo on the planet to be bolted to the EVO X without worrying about cracks. The only other option I see is the ATP T4 cast unit which has about ZERO known uses (at least on this forum), or a MAP manifold with a stock frame turbo. That manifold does have larger runners than OEM, and they have flow data showing it is an improvement from stock.

 

Thanks for the info. I'm seriously debating on just buying new oem longblock, replace oil cooler, and toss my old parts back on. Decisions, decisions.

 

The stock manifold and stock frame turbine housing crack too. All of it cracks. The tubular manifold is at least repairable when it cracks.

 

I haven't heard of a cast stainless steel manifold cracking. Does that happen?
Yes my OEM cast steel manifold did get a hairline crack in it. I thought the tubular manifolds crack like crazy when subjected to daily heat cycles.... Am I wrong?

 

Well, there aren't cast stainless manifolds available that I would use based on spool characteristics (the MAP manifold loses 400-500rpm of spool-up from what I've seen). And the AMS turbo kit is disco'ed.

I wouldn't say the tubular manifolds crack "like crazy". I think I've seen one that cracked, and it was 4-5yrs old. Fixing it was an easy "weld 'er up" after pulling the manifold. I've seen wayyyy more crack OEM manifolds and turbine housings than I have turbo kit tubular manifolds and/or stock frame tubular manifolds.

 

I don't know about that. With my 5858 Gen 1, in 3rd gear:

20psi - 4200 rpm
24psi - 4350 rpm
27psi - 4500 rpm
29psi - 4750 rpm

So if I had that same turbo with a tubular manifold it would hit 20psi at 3800rpm and 27psi at 4000rpm? I highly highly highly highly doubt that.

My Evo with the stock motor and stock turbo on E85, in 3rd gear:

20 psi - 3200 rpm
25psi - 3500 rpm

 

I was referring to the the MAP stock frame replacement manifold, vs the stock exhaust manifold.

The turbo kit manifold was such a limited run, I've never even seen one in person, and the only results I've ever seen have been yours from your car.

 

Right but Jaraxle was referencing the v-band MAP cast manifold, not the oem replacement.

 

idk what he was referring to.

My point was you can have an OEM manifold that will crack. Or a tubular manifold that will also eventually crack...lol.

 

I will stand by my statement that cast stainless steel manifolds do not crack. Tubular manifolds vary from "crack like crazy" to "will crack at some point" depending on the quality of the materials used, the weld quality, and the number of heat cycles that it has endured.
Because of this, I would choose a cast stainless steel manifold over all other materials.

A separate but worthy discussion is the FLOW design of the manifold, which will indeed change spool characteristics, top end performance, etc.
On my build thread I had just posted about the different cast Evo X manifolds that are "disco'ed"...

 

Disco'ed is short for discontinued

Yes, cast stainless manifolds don't crack. There just aren't any available that I would use based on performance.