My primary turbo is smoking again, so I'm left with 3 options.
1)Swap in another used core and see how long it lasts
2)Upgrade to BNR's
3)Go single

Option 1 is the easiest/cheapest.
Option 2 will last longer than option 1 and give more power. Yay
Option 3..
Well, it would will simplify the car, lower the heat, add some reliability, most expensive (short run), etc....

I don't care about big power, I care more about the quick spool of the factory seq twins. Last time I dyno'd the car I was at 270, so jumping to even 400 sounds like a big jump. I'm pretty sure I would be more than happy with even 350. Are there any single options out there that would come close the the spool of the stock twins? I will be running pump gas. I don't have a full upgraded fuel system in place yet, but all I would need is secondaries (probably ID 2000). I already have FFE rails, and id725 for primaries purchased. I do have a Bosch 044 already installed. I am running a PFC w/ datalogit.

I looked at the GT30R, but it has an internal wastegate. No go.
I've looked at dyno sheets with the GT35R and it just doesn't seem quick enough compare to stock twins, but realize it is a viable option.
Dyno sheets with TD04 series seem to spool slower than the GT35R.

I am unfamiliar with BorgWarner or Precision options or have not been able to find suitable dyno's. Can some of you single turbo experts push me in the right direction please?

 

I have been tuning stock turbo's in sequential mode lately. I own a GT3574R single turbo.

I swapped mine to this and have been very happy. The power is delivered in a controled smooth manner and has a good amount. The turbo's put down over 200WHP before 4,000 RPMs, not too many stock turbo's have done this.

 

Do you have a dyno sheet I could look at?

 

I think people get to caught up on a PSI number at a low rpm when all that really matters is how much TQ and HP a turbo makes. How much boost do you plan to run?

 

My choices are in this order:

-Borg Warner Airwerks (for longevity, reliability and good performance)

-Borg Warner EFR (talk with Geoff at full-race about where the EFR stands at current moment and manufacturing.

-Factory Garrett units (true Garrett units, not added onto from shops with their wheels etc)

I just bought a BW FMW s362 and about to install it shortly.

 

An Apexi RX6 kit sounds like it's right up your alley. I've been secretly thinking the same thing as you, but for different reasons (just want to simplify), and the RX6 kit is the one I've been eyeballing.

 

Since I only have 92 octane available, I will try to be "safe" and stay under 15 psi.

 

Borg Warner EFR 7670 Turbocharger

 

You have tons of options and this forum is a great resource for going single. Pretty much all of the single turbos suggested here are going to surpass what you consider "fast spooling twins" at any usable rpm level. Believe me you will wonder why did not do it sooner. My cheap and large mid sized S366 has a unbelievable torque/power band.

If I had a clean slate the EFR options look extremely inciting. BOV and wategate are built into the turbo! Talk about a easy install and super clean engine bay. The initial cost seems a little high but when you consider you do not need to buy a waste gate or BOV and the fab costs that go with them its a bargain.

For absolute bargain pricing, reliability and great performance I would probably go with a S363.

 

I wouldn't go any smaller than a 62mm turbine wheel unless you like higher back pressure, higher EGT's, and power to drop off over 6800rpm. The problem lies in the housing options available on a 62mm wheel. If power wasn't a major concern and the car is mainly street driven a 58/62 with a divided .84 housing from Precision is a very responsive turbo. I'd prefer a 1.0 and have been pushing them for it but the .84 will work well, a few years back people were running T4 "inlet" housings from Garrett in .82 and were very happy with the response and overall performance it delivered.

~S~

 

"I think people get too caught up on a PSI number at a low rpm when all that really matters is how much TQ and HP a turbo makes." Neutron

PSI does not necessarily correlate w power as Neutron correctly states. you can have lots of psi but a modest amount of oxygen molecules into the engine as in the stock setup. a single turbo will produce more power per psi.

"I just bought a BW FMW s362 and about to install it shortly."...... turbowash

would also be my pick

"An Apexi RX6 kit sounds like it's right up your alley." Natey

a very nice turbo with a fit compressor-wise however the turbine wheel is really too small for a rotary. see comparo below

"You have tons of options and this forum is a great resource for going single. Pretty much all of the single turbos suggested here are going to surpass what you consider "fast spooling twins" at any usable rpm level. Believe me you will wonder why did not do it sooner." Neutron

agree

"I wouldn't go any smaller than a 62mm turbine wheel unless you like higher back pressure, higher EGT's, and power to drop off over 6800rpm. The problem lies in the housing options available on a 62mm wheel." Zero R

agree.

most of the above points in one direction... the BW S300 PN 177272 or 177280.

the compressor is quite similar to the GT35 which is a great fit for your objectives BUT the hotside is much more rotary friendly.

here are the numbers:

..........................average area in square inches

.....................compressor................tur bine (hotside) wheel

GT3582r.............6.386......................... .....5.171

BW S300............6.435............................. .6.31

RX6....................6.356...................... ........4.315!!!!!!!

BW EFR 7670.....5.524..............................5.229 (very light weight)

FD OE Twins.......5.972...............................5. 25


Compressor wheel trim encourages early spool. lower number is better spool

GT3582r 56

BW S300 51

RX6 55

BW EFR 7670 56

OE Twins 52


all four turbos are excellent suggestions however, IMO, the BW S300 (often referred to as a "62" but is really a 60 inducer) has several advantages for YOUR objectives...

a really large turbine wheel which better suits the rotary and a a 51.4 trim which encourages earlier spool. the BW EFR, while initially more expensive, includes an internal wastegate as well as a lighter spool friendly turbine wheel.

as you can see, the stock twins do have large enough wheels to make single turbo power but are handicapped by the unfortunate manifold design.

howard

 

Glad to see another rotary in Missouri, I believe I've seen you on the KCSR forums.

I'd personally go with a 6266 from Precision with a decent sized exhaust housing. You'll be able to achieve your goals without breaking a sweat or breaking the bank.

I've run both the 6265 and now the 6766 on my car and they've been great. There's a dyno video in my signature of the 6265 (New version is 6266)

 

Yep that's kinda where I am at with it. If I can get PT to make me the 1.0's for the 62mm turbine then maybe that would be a bit better in this case. but either a 58/66 or a 62/66 both in BB are good performers. I like the 66 wheel. It just performs we had a EVO here put out 1040whp on a 67/66 it's hard to complain about those numbers out of that size "frame" turbo.

~S~

 

OP, if you're still considering a nice small-ish single, you may want to check out the turbo kit i have for sale.

it's a precision 6262 (very close in size to a GT3582R, but with a bigger turbine wheel) kit with a turblown dual wastegate manifold, dual MV-S watercooled wastegates, high quality 304 downpipe with wastegates recirculated. it has pretty good boost response. made 380whp (dynojet) at 12psi. ready to bolt onto the car...
check out my FS thread in the 3rd gen FS section.