I am currently turbo shopping and came across one of these for a deal, anybody know how it will perform on the street, it is ball bearing, my only concern is the t-25 turbine.

Dual Ball Bearing GT25/40-R Turbo assembly with specified ar. T25 style inlet flange with 5 bolt style exit. Large 60- 1 style compressor housing with 4.00" inlet and 2.50" outlet. Very Good response turbo for 4 Cyl applications. This turbo has a flow capacity of about 450HP.

Turbine
-Wheel: 53mm w/ 62 trim
-Housing: .64 ar, .86 ar
-Maps: Not Available

Compressor
-Wheel: 60mm w/ 60 trim
-Housing: .70 ar

 

I´m interested in some experiences or infos too..

 

My car is to be dail driven, not some ungodly dyno queen or track monster, and i think this would be a good turbo for repsonse and power, it made 440whp on a 944 turbo quite nicely

 

Would be great to see a dyno sheet of a honda/acura engine.. mine is a daily driver too and I´m standing between the GT30R and this one...

 

somebody has to have an opinion, how concerned should i be about top-end with this turbo, ?

 

Well, I guess I'll throw in some experience here. This turbo has been out in Nippon for over 4 years, and Garrett has recently brought this monkey to the states. It's mainly been used in pairs on Supras and Skylines, and singly on the occasional Silvia. They have great response, and good spool, but only higher than boost pressures above 15-18psi. These turbos need to be spooled VERY highly in order to get the expected hp that you'd expect in many situations from a standard bearing turbo of similar size. Remember, the GT2540 Utilizes a GT40 Compressor wheel, which for a B16 Motor is very laggy to use. This Compressor size is also used in the SC61, and for the B16 doesn't even BEGIN to spool until about 4400rpms w/ max boost on 8 psi at about 5000 rpms, regardless of the turbine T25 sizing with the .48A/R. The B16 unfortunately does not have the exhaust gas characteristics and unless the motor is built to hold over 15psi, the GT2540R won't be the most effective turbo to use on this application..

Below are some specifications that I created for the B16A based upon stock compression and 8 psi (or 1.54 Pressure Ratio)

Max RPM Displacment Corrected Flow LBS/MIN FWHP
2800 1595cc 150.2616693 10.5818077 101.58HP


8100 1595cc 434.6855435 30.61165799 293.45HP





Modified by TheShodan at 3:24 PM 8/30/2004

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TheShodan &raquo;</TD></TR><TR><TD CLASS="quote">Well, I guess I'll throw in some experience here. This turbo has been out in Nippon for over 4 years, and Garrett has recently brought this monkey to the states. It's mainly been used in pairs on Supras and Skylines, and singly on the occasional Silvia. They have great response, and good spool, but only higher than boost pressures above 15-18psi. These turbos need to be spooled VERY highly in order to get the expected hp that you'd expect in many situations from a standard bearing turbo of similar size. The B16 unfortunately does not have the exhaust gas characteristics and unless the motor is built to hold over 15psi, the GT2540R won't be the most effective turbo to use on this application..

Below are some specifications that I created for the B16A based upon stock compression and 8 psi (or 1.54 Pressure Ratio)

Max RPM Displacment Corrected Flow LBS/MIN FWHP
2800 1595cc 150.2616693 10.5818077 101.58HP


8100 1595cc 434.6855435 30.61165799 293.45HP


</TD></TR></TABLE>

SHODAN...ur a rude boy! awesome info

 

We're running that turbo on a sr20det s14 240sx.It spool's up extremely fast and has pulls awesome at nearly any rpm,especially 5k+.We've gotten it up to 19lbs so far,but the engine was bone stock...headgasket and all...so I thought that should be enough and took it apart to replace the headgasket and build the head.I'd recommend this turbo to most street guy's looking for somewhere in the 300-400whp range.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDMotive &raquo;</TD></TR><TR><TD CLASS="quote">I'd recommend this turbo to most street guy's looking for somewhere in the 300-400whp range.</TD></TR></TABLE>
On an SR right?

 

It's on an sr right now...but its such a good turbo that im sure that it would be very good on most Honda engine's.We were thinking about using it on the K20 but were going all motor with it.

 

TheShodan, Could you possibly calculate the power rating at 10, 12, and 15 psi? possibly at 1 more point along the rpm curve?

 

hrmmm

gt3040R spool times (.82 a/r)
stock b16. 6 psi by 4800-5000 rpm
stock 1.8. 6psi by 4300-4500 rpm.
people have reported 15 psi by 4500 rpm . the turbo does see boost in the 3500 rpm range and builds.

great turbo.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDMotive &raquo;</TD></TR><TR><TD CLASS="quote">We're running that turbo on a sr20det s14 240sx.It spool's up extremely fast and has pulls awesome at nearly any rpm,especially 5k+.We've gotten it up to 19lbs so far,but the engine was bone stock...headgasket and all...so I thought that should be enough and took it apart to replace the headgasket and build the head.I'd recommend this turbo to most street guy's looking for somewhere in the 300-400whp range.</TD></TR></TABLE>


Please remember that the Bore, stroke, engine compressrion and other characteristics of the SR20 are completely different than that of a B16 Honda. In realtive principle it could work, but you stated it yourself that this was up to over 19psi for such an application..

for a b16 4500-5000 rpms on a GT35R (GT3040) or the GT2540 would be laggy because of the GT40 compressor side.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wantboost &raquo;</TD></TR><TR><TD CLASS="quote">TheShodan, Could you possibly calculate the power rating at 10, 12, and 15 psi? possibly at 1 more point along the rpm curve?</TD></TR></TABLE>


I'll see what I can get by this evening

 

the turbine wheel is WAYY too small for that compressor. We have used that setup and only got a lot of lag with poor top end.

 

RIght now I have a t3/t4 57 trim .63/.60 ar's turbo from cheapturbo.com. I was thinking about changing turbo's as this one gets full boost by about 4700rpms, I wanted something that would spool up quicker but still pull in the top end. This is on a pretty stock gsr with log mani @ 10psi, made 281whp, 181tq. I'm only looking for maybe max whp of 350. Just want a more fun turbo for my everyday driver.

Shodan, any suggestions on a BB turbo that would suite my needs?

 

keep your turbo and dotn worry about it.

4500-5000 on a b16 with gt35r .82 EXH a/r is pretty good .

the gt30 exh side is almost a mismatch so a 25 turbine..ick

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike1114 &raquo;</TD></TR><TR><TD CLASS="quote">RIght now I have a t3/t4 57 trim .63/.60 ar's turbo from cheapturbo.com. I was thinking about changing turbo's as this one gets full boost by about 4700rpms, I wanted something that would spool up quicker but still pull in the top end. This is on a pretty stock gsr with log mani @ 10psi, made 281whp, 181tq. I'm only looking for maybe max whp of 350. Just want a more fun turbo for my everyday driver.

Shodan, any suggestions on a BB turbo that would suite my needs?</TD></TR></TABLE>

Actually, that's pretty good. you don't want spool TOO early, or you wind up spinning tires. I'd say the GT30R, if you MUST go ball-bearing. But your efficiency won't be realized untill you up the boost past about 14 psi or so. Otherwise I'd say the GT32E as a second choice, though that is 360 degree standard bearing

 

just use a .48 a/r turbine housing on your 57 trim and youll be happy.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Full-Race Geoff &raquo;</TD></TR><TR><TD CLASS="quote">just use a .48 a/r turbine housing on your 57 trim and youll be happy.</TD></TR></TABLE>

agreed. the .48ar would be perfect.