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TPC Ball Bearing IS38

Diggs24

Autocross Champion
Location
de plains! de plains!
Car(s)
2015 GTI
it doesn't need dynos, it uses oem spec wheels so it will make the same power as an oem is38. Where it makes "more" power is the ability to hold boost all the way to redline and not have to taper. So you can run whatever boost level an is38 can run before it becomes a hair dryer.
Ok, so taking a pump gas IS38 that makes peak 360whp@5500 and then tapers down towards redline this turbo can make 360whp all the way to redline? So, no further peak power just more power under the curve?
 

JerseyDrew77

Autocross Champion
Location
Virginia & NC
Car(s)
2016 TR GTI S 6MT
I thought a ball bearing spooled a little sooner getting into boost faster.
yes they do spool quicker but the main advantage of a BB over JB is their ability to hold higher thrust loads ( ie more boost)
They do spool quicker which gives you a longer powerband, like I said. For an example, a JB turbo spools up at 4500 rpms while the BB spools up at 3000 rpms, same power but just a longer powerband.
 

jimlloyd40

Autocross Champion
Location
Phoenix
Car(s)
2018 SE DSG
They do spool quicker which gives you a longer powerband, like I said. For an example, a JB turbo spools up at 4500 rpms while the BB spools up at 3000 rpms, same power but just a longer powerband.
Ok so same power but quicker in a race.
 

THEREALVRT

Drag Racing Champion
Location
The great white north
Car(s)
Golf R
They do spool quicker which gives you a longer powerband, like I said. For an example, a JB turbo spools up at 4500 rpms while the BB spools up at 3000 rpms, same power but just a longer powerband.
the difference is not that great, i usually quote 200-300 rpm sooner on aa single gear pull, but yes, the powerband would be longer as you are not tapering the boost down in this turbos case. Plus for the manual guys a ball bearing setup is much quicker to respond during shifts.
 

El_bigote_AJ

Autocross Champion
Location
Las Vegas
Car(s)
2019 GTI bunny
Ok, so taking a pump gas IS38 that makes peak 360whp@5500 and then tapers down towards redline this turbo can make 360whp all the way to redline? So, no further peak power just more power under the curve?
I would think if a car is making 360whp at 5500 at xx-psi and xx timing, wouldn’t it make more power at 6200k (marginal probably) at the exact same psi and timing since you’re moving more air and fuel ? As long as heat stayed level/in check.
 
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FB-GTI

Passed Driver's Ed
Location
MO
Car(s)
VW GTI -> Golf R
Heck of a price. Power numbers should only be like any other IS38. Unless ball bearings add a few HP.
Since the bearings are the only change the compressor efficiency and turbine inlet pressure are going to be the same as with IHI IS38. Boost onset is probably not much different since the IS38 already spools rapidly. Long-term reliability is likely the main benefit, of course that depends on the quality of the bearing system, just because it is ball-bearing doesn't mean it will last a long time.
 

THEREALVRT

Drag Racing Champion
Location
The great white north
Car(s)
Golf R
Since the bearings are the only change the compressor efficiency and turbine inlet pressure are going to be the same as with IHI IS38. Boost onset is probably not much different since the IS38 already spools rapidly. Long-term reliability is likely the main benefit, of course that depends on the quality of the bearing system, just because it is ball-bearing doesn't mean it will last a long time.
it is the same bearing system we use in our hybrid turbos whether that be our mqb, evo x or subaru, gtr etc performance turbos
 

scrllock

Drag Racing Champion
Location
MI
typically journal bearing would be more durable, that's the trade-off you get for spool.

dyno would definitely be useful, big diff between power going all the way to redline and say, 6000 rpm.
 

Navi

Autocross Champion
Location
BK/NYC/Hamptons
typically journal bearing would be more durable, that's the trade-off you get for spool.

dyno would definitely be useful, big diff between power going all the way to redline and say, 6000 rpm.
is this true? i always heard the opposite, but I'm no expert
 

Ed @ EQT

GOLFMK7 Official Sponsor
Location
Fairfield, CA
Can someone please explain to me how the bearing system has any impact on how much boost the turbo will hold while staying efficient?

Hint: it doesn't. The reason we and most other tuners taper boost on an IS38 is because the compressor wheel is not efficient at higher boost levels at higher RPM's. Holding boost up there only creates heat and can actually reduce power. This has nothing to do with the bearing system and everything to do with the compressor wheel being completely tapped out.

-- Ed
 

mike-y

Ready to race!
Location
Los Angeles
I would think if a car is making 360whp at 5500 at xx-psi and xx timing, wouldn’t it make more power at 6200k (marginal probably) at the exact same psi and timing since you’re moving more air and fuel ? As long as heat stayed level/in check.

Yes. The definition of HP = (Torque x RPM)/5252. If you are able to make more torque at a higher RPM, you will be making more HP. If you are making 360hp at 5500rpm, you are making about 344 ft lbs of torque at 5500rpm.

If you can sustain the same 344 ft/lbs to 6200rpm, you will be making 406 hp.

EDIT - Not saying this turbo will do that, this is just how the formula works. If you were able to make the same amount of torque at higher rpm, you would make more HP.
 
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