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-   -   Quick question re turbo suitability (https://www.rx7club.com/single-turbo-rx-7s-23/quick-question-re-turbo-suitability-1075068/)

96fd3s 11-27-14 04:32 AM

Quick question re turbo suitability
 
Hey guys, im just after a bit of info as to the suitability of a turbo for my wants/needs..

My car has had sequential twins ever since i got it quite a few years ago (running stock 16bit ECU), and I have started thinking id like to convert it to single turbo for a bit more power and consistency of power delivery..

I daily drive the car, and i think I would be happy with a responsive 350whp setup.

I acquired a turbo for a really good price without really having an idea if its suitable for what I want..

Specs are as follows..I had a bit of a read of the compressor map thread to try to make sense of it all but am still confused..

Its a gt3540, with a T3 Flange..

Turbine Housing A/R:.82
Comp. A/R:.70
Turbine wheel size:67.8 in ,76 out- trim 55
Compressor wheel size:61 in , 81.7 out - trim 48

I searched gt3540 a lot but pretty much all referenced a t4 flanged version..

Will this turbo do it for me? i.e. 350whp? responsive? (with supporting mods of course)
From what little I understand i don't think im asking too much, but really I have no idea.

I would prefer to make the manifold a t3 flange, over getting a t4 flanged turbo if I can get away with it.

cheers

96fd3s 11-27-14 05:40 PM

I worked out the area of the turbo's wheels (in inches :scratch:) as per Howard Colemans thread. :icon_tup:

I came up with;

Compressor wheel area = 6.33"
Turbine wheel area = 6.31"

For a relationship of 99.98%

I guess I should just proceed and use a t3 flange? Will it hurt that much considering my goals?

The wheels area looks to be of an ok size for my applications (i think).
cheers

rx72c 11-28-14 01:52 AM

I think thats a great little turbo. Should be very responsive and should reach your target HP goals.

BLUE TII 11-28-14 02:30 AM

T3 flange GT3540 will be great for your power goals/use as the smaller volume exhaust manifold runners and turbo exhaust housing will provide move velocity for faster spool and still support 350rwhp fine with that big exhaust wheel.

I would prefer to make the manifold a t3 flange, over getting a t4 flanged turbo if I can get away with it.

Yep, do that.
I would avoid a log style collected manifold if possible though and make one where the runners are near parallel to each other at the turbo flange and thus merge at a shallow angle into the T3 open volute flange.

96fd3s 11-28-14 02:20 PM

Cool thanks for that guys, just needed a little reassurance :nod:
Will try fab up a manifold just for it :icon_tup:

96fd3s 01-11-15 06:52 PM

Change of plan, am now going with a borg warner S360, T4 divided/twin scroll

I decided it was too much hassle for what its worth to do it properly with the T3 flange turbo.

I could not find any T3 manifolds, and having a manifold fabbed especially for it (with either smaller dia runners, or runners that tapered down to a T3), was too much money & effort then it was worth putting in to run that turbo.

And i could not bring myself to use an adapter, or weld a t3 flange onto a T4 manifold and screw the flow up majorly.

So im a few hundred down on buying that other turbo, but I think ill be better off and happier in the long run.

rx72c 01-11-15 06:54 PM

Make you run a twin gate setup with the twin scroll.
Really does make a substantial difference to spool.

96fd3s 02-03-15 07:16 PM


Originally Posted by rx72c (Post 11854408)
Make you run a twin gate setup with the twin scroll.
Really does make a substantial difference to spool.

After lots and lots of reading, weighing up options, studying the theory of it all... I have an IRP twin wastegate/twin scroll manifold in the works :icon_tup:

I have already wasted money on crap, where that money could have been put towards what I should have just got in the first place.

I know its been said so many times... But, do it once, do it right. Even if it takes a whole lot longer. You will come out better off in the long run :nod:


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