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-   -   What are my options for turbo manifolds. (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/what-my-options-turbo-manifolds-215495/)

82streetracer 08-17-03 08:08 PM

What are my options for turbo manifolds.
 
Im looking for a t04b divided turbo manifold, external wastegate

I was looking at the hks cast one but this is going on a FB and I was told that it gets to close to the idler arm and fries the bushings.

I was also looking at the OBX manifolds on ebay. but dont you have to add spacers to keep the turbo from hitting the manifold?

Post some links.

82streetracer 08-17-03 08:11 PM

Sorry its a 91 Jspec motor.

Scott 89t2 08-17-03 08:20 PM

the HKS one is not divided. your best bet is probably to find someone local to custom build one to fit in your car. it won't be cheap. $1000+ probably. but they are $1000 for the FC too if you can find one.

Ryde _Or_Die 08-17-03 08:41 PM

I believe someone locally sells SS divided ones for like $500 or so. I am planning on using one. I'll post in here when I get more details. A friend said they look reallll nice.

ERAUMAZDA 08-17-03 10:25 PM

why is divided so speical

Ryde _Or_Die 08-17-03 10:43 PM


Originally posted by ERAUMAZDA
why is divided so speical
From my research, faster spool and better top end.

ERAUMAZDA 08-17-03 11:22 PM

Is that because the air has to be forced through a smaller diameter.

Scott 89t2 08-17-03 11:57 PM


Originally posted by ERAUMAZDA
Is that because the air has to be forced through a smaller diameter.
it's sorta the same as having true dual exhuast on an N/A. each rotor is seperate untill only right before the turbo blade. instead of meeting each other right outa the engine.

Evil Aviator 08-18-03 12:26 AM


Originally posted by ERAUMAZDA
Is that because the air has to be forced through a smaller diameter.
Somewhat. The total cross-sectional area is the same, or only slightly less, than an undivided manifold, but the smaller diameter of each section maximizes the velocity of each exhaust pulse. This helps spool the turbo faster at low engine rpm, but it doesn't create very much of a restriction at higher flow rates. Technically, with everything else being equal, an undivided manifold would cause less drag due to its reduced surface area vs. a divided manifold, but divided manifolds seem to yield the best overall performance on engines with few exhaust pulses per revolution, like 2-rotor engines and 4-cylinder engines. A divided manifold doesn't make much difference on engines with multiple cylinders or rotors, and its performance advantage is also reduced at higher engine rpm. An additional advantage of the divided manifold is that the exhaust pulses do not mix and cause interfering turbulence or reversions with each other. This is one of the tricks used on the S5 turbo manifold that allows it to spool the turbo so fast without the fancy 2-stage actuator ala the S4.

Note that you really need to use a turbo with a divided scroll to take advantage of the divided manifold, and vice versa.

82streetracer 08-18-03 03:09 PM

yeh, my turbo is divided.

I emailed someone at RX7store.net and asking if the HKS manifold was divided, The guy said it was.

I could fab up the pipes but I would have to have someone weld them.

Where can I get a 13b exhaust flange in Stainless?

banzaitoyota 08-18-03 03:33 PM

Have a shop cut you one with a PLASMA CUTTER or a Water-Jet

pillage6 08-18-03 03:45 PM

My manifold is cracked and was wondering where to buy a new turbo manifold also, any help is appreciated.

A guy in town said he could make me one, but a known company would be worth the extra money.

rxse7en 08-18-03 03:58 PM

WestJaxVert got his made at Speedcraft here in town. I seem to remember it was in the $300 range.

pillage6 08-18-03 04:02 PM

Yeah, the only hard part is that they are on the other side of town and I work 9-5 mon-fri.


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