TOMEI EVO 7

Greddy T-67 25G VS. HKS 3037S

Which Turbo is bigger?

Which Turbo is capable of producing more HP?

Does anyone have the possible max HP of each of the Turbos?

Overall, which Turbo is better and which one would you go for?

TOMEI EVO 7

?

Rez90

iTrader: (17)

i believe the 25G is a bit bigger. Probably capable of more top end HP. but i would assume the lag would be a pretty large factor with this turbo. Considering a 20G has a decent amount of lag on most DSM's, the 25G would have even more. i wouldn't doubt that the top end power on a 25G is absolutely crazy but as far as streetablilty i would go for the HKS. Less lag equals more usable power. and the 3037s is still a pretty freakin big turbo.

just my .02

94AWDcoupe

iTrader: (125)

Tsukuba circuit is what America needs. A place to go test your car around a 1.3 mile roadcourse. JUN cars are holding the #1 spot and the #3 spot. They run the 25g on those cars. But they are 2.2 EVO 5 and 2.5 liter Subie cars.

The #2 record time is held by a EVO 7 built by HKS. It runs the way overpriced hks3240.

The 25g is a more powerful turbo than the 3037 on the correct setups. The 3037 would be a better choice for a 2.0 powered car.

My 25g gets 25 pounds of boost at 4100rpm with my 2.4 liter. I love my 25g and would trade it for nothing at this point. The guys down in Miami love this turbo too. They are not afraid to hang them on 2.0liters. They say they are getting full boost at 3800-4000.

I believe the header that comes with the greddy kit may be hurting fast spool up. A big header can loose too much heat before it hits the turbine housing. But this is pure congecture so take that with a grain of salt.

maki

iTrader: (7)

greddy turbos are great, but for some reason people underestimate them. Not only are they stronger and will last longer then ball bearing hks, with proper tuning they produce huge hp.

articfury

iTrader: (1)

maki-

Do you have some empirical data that the ball bearing GT turbos are weaker or more susceptible to damage? Some failure rate data would be interesting. I would just like to see something other than conjecture on the subject.

Here is a document that Garrett published regarding GT vs. T turbos:

http://www.turbobygarrett.com/turbob...eaflets3_1.jpg

Here is one comparing Ball bearing vs Journal bearing:

http://www.turbobygarrett.com/turbob...eaflets3_2.jpg

I wish the charts on these were more clear.

I tried to find a matching documents from GReddy or Mitsubishi, but couldn’t find any. If anyone has some please post them.

maki

iTrader: (7)

Greddy turbos use thrust bearings, so will last longer than the ball bearing types.
There will always be conflicting studies, but ball bearing turbos are weaker then non bb. I know that from personal experience, from my friend who is a rally driver in europe. He drives group N rally car, and JUN engineers said the same thing, I have no reason to dubt those people.
BB spool only a little bit quicker, its not really noticable difference, despite what most people here think.


non ball bearing turbo evo8
2600 rpm 0 boost
3000 rpm 0.5bar
3400 rpm 1.35

ball bearing turbo evo8
2600 rpm 0 boost
3000rpm 1bar
3200 rpm1.35bar

Coolguy949

iTrader: (10)

I would definately go with the GReddy over the HKS. It has a beautiful manifold and is probably the highest quality turbo kit i've seen for the evo. Personally, i'm in love with it...

Fourdoor

iTrader: (11)

I think that is a nice kit also....but that is NOT an equal length manifold setup

Keith

maki

iTrader: (7)

I was importing those for a while but since everybody was asking about hks I stopped.
If you want it let me know.

WILDMAN

iTrader: (2)

I have been considering a GT30R set-up vs. BR475 set-up. Now I see this T-67 and that sparks my interest as well. Can anyone elaborate on how these would compare as well? Sorry, not trying to boost your thread, but that T-67 looks pretty tasty too.

Anyone?

maki

iTrader: (7)

I dont have any experience with gt35, why did you decide on it?
heres some turbo info
http://www.evonation.com/forum/viewtopic.php?t=12

articfury

iTrader: (1)

Mak,

Again, you state that journal/thrust bearing turbos are more reliable without quoting any documentation.

JUN has a well documented relationship with Trust/GReddy. I highly doubt that they are going to state that HKS/Garrett dual ball bearing turbos are better than the Trust units they use.

Garrett Dual BB turbochargers power most of the top WRC, CART, and LeMans cars. Several top Import Drag cars also use Garrett turbos, including the NHRA Sport Compact Hot Rod Championship won by Marty Ladwig with a GT40R. The drag racing turbos are most like the turbos one would by off the shelf. More info can be found at the two links below.

http://www.egarrett.com/motor_sports...orts_index.jsp
http://www.turbobygarrett.com/turbob...ide/index.html

As for BB only spooling a little quicker, your example actually makes a pretty strong argument for BB.

7.35psi more boost at 3000 RPM is a significant difference. The initial response of the BB turbo is obviously better. If we had a chart of boost over the whole range, then we could probably extrapolate more data. i.e. the point at which the 2 turbos overcome inertia. A similar comparison of larger turbos would be interesting.

Also, is the BB turbo you reference a dual ball bearing?

Jon,

The GT35R comes in two flavors:

Compressor:
- Wheel Dia - 82mm
- Trim - 56
- A/R - 0.70

Turbine:
-Wheel Dia – 68mm
- Trim – 84
- A/R – 1.06 or 0.82

The only difference being the A/R for the Turbine side. 1.06 or 0.82.

The HKS 3037 comes in several sizes that are smaller or in between the Garrett sizes.
The GT30R is more closely sized to the 3037. See the link Mak posted for more info on the HKS sizes.

All the manufacturers make suitable turbos for most applications. It often just comes down to preference in kit manufacturer, price and availability.

Derek

fastevo2004

How much power does the GT35 support?

Also what turbo does the Greddy use?

aaronyoung

the 35r can suport@650whp at its utmost limit (if the engine has the works i.e. cams ported head, standalone)

the greddy t67 is a mitsu 25g hybrid @500whp (maybe 550 at it's utmost limit)

IMHO the t67 is easily compaired to the 3037s as far as power goes. The 3037 gets the edge with the ballbearings. At a ofset in cost ofcourse.

For the money the greddy kit is very nice. The WG alone is in the $500 range. Greddy always has had crapy supply lines though, an easy fix. So plan on replacing it at about $65

for the money I'd chose the greddy kit.

aaron