Garrett 38R 1.0 vs 1.15 dyno test

[Lowdown89]

Maybe we can get enough guys to throw down and get that done. I would throw in a lil $$ to see numbers, I am goin with a similar injector setup with my 38r and will be putting my stock housing on, after seeing these results.

Thanks for posting all this, been a good read..

Your welcome, that's the whole reason why I have tried to make sure everything we do is posted up so everyone can see what works and what dosen't.... I'm not finished with the truck yet, still have the gears to install along with the transmission that bill is gonna do, I also have a sump, fluidampr, new fan and some fancy mishimoto radiator hoses lol that I will prob do after I get the truck back from Bill not that it's gonna add any real performance haha just wanna clean it up under the hood as much as possible

 

[TyCorr]

Bill, as for.the effects of the bmw has on a 38r, could the reason for the loss in overall performance have to do with the fact that the 38r is EXTREMELY efficient right off the shelf? Its optimized for what we do with it. I personally feel that many of the jb turbos(bw s-series mostly) are seeing such huge improvements because they are leaving so much on the table to begin with with the cast wheels. There may be a reason in that fact.

The 38r is awesome on a stock truck, a stock truck with a chip, a stocker with a fuel system, and an upgraded set of stg IIs are nice with it. I cant wait to.experience it with some hybrids.

 

[Gearhead]

Interesting numbers! My old SOTP meter didn't notice a huge performance when I went to the 1.15 but the EGT drop alone was worth it for me, along with not having to hear that flutter sound whenever I got on it good. Sucks that I might have lost 20 or so hp doing so.

It's a shame that the thing didn't come with a bigger exhaust wheel. That would take care of most of the percieved problems with this turbo. You could also use the wastegate at part throttle to dump some extra drive presure just like the factory intended and have the same effect. At the end of the day the 1.15 doesn't make much difference up top because the wheel itself is the restriction. If you drilled the divider and used the wastegate you can have more power everywhere when compared to the 1.15 since you can drop the drive pressure that you can't do with the non wastegated 1.15. I have seen a whopping 6hp gain on a truck with cam and heads that makes extra drive pressure when compared to stock components when swapping to a 1.15 housing.

 

[Power Hungry]

For reference, I did cross drill the divider in the turbo housing and noticed no gain up top. It may make a difference on the street as far as surge control, but I never really noticed any surge anyway.

 

[JAP]

It's a shame that the thing didn't come with a bigger exhaust wheel. That would take care of most of the percieved problems with this turbo. You could also use the wastegate at part throttle to dump some extra drive presure just like the factory intended and have the same effect. At the end of the day the 1.15 doesn't make much difference up top because the wheel itself is the restriction. If you drilled the divider and used the wastegate you can have more power everywhere when compared to the 1.15 since you can drop the drive pressure that you can't do with the non wastegated 1.15. I have seen a whopping 6hp gain on a truck with cam and heads that makes extra drive pressure when compared to stock components when swapping to a 1.15 housing.

:whs: And while it its on a dyno, now would be the best time to see.

 

[TARM]

Matt,

Basically we want the specs of some of those "pull off" Garrett turbos, as tend to have the comp wheel size of a 38R but the turbine wheel of the 40 or 42 series depending on which one. Issue of course is they are setup in standard not reverse so we end up being at a T4 mount and then there are many choices.

 

[Gearhead]

I am looking for my notes but I think the exducer of the 38r's turbine is like 69mm.

 

[Gearhead]

We would be better served with something in the 75mm neighborhood even if we keep the 66mm compressor.

 

[TARM]

gt40 series uses a turbine wheel of 77mm/68mm With the 4088 its matched to a 64.7/88 comp wheel and in the 4094 matched to a 67.8/94 comp wheel

That compared to the 38r which is a Comp:65.86mm/88mm Turbine: 76.20mm 67.73mm

Based on those numbers and that the turbine wheel uses comp wheels that splits slightly smaller and larger than what the 38R is, this looks like the turbine wheel for the 38r.

Not sure if it can be done but taking a gt40 turbine wheel onto a 38R shaft and then machine the housing to allow it to fit?

 

[neverkickn]

What are the specs on a van turbine shaft assembly just for comparison.

 

[Gearhead]

I just confirmation that the factory turbine exducer is acutally less than 68mm. The issue with parts compatibility is that the 38r is a reverse rotation charge so you can't pull any parts from any of the other garrett t-4 style turbos.

 

[MadDiesel73]

Van turbo turbine

 

[Tom S]

I missed this the first go around. I found this information super interesting so I pulled this out of the other thread. It looks to me like the original engineers actually did some pretty good work.

 

[Lowdown89]

I missed this the first go around. I found this information super interesting so I pulled this out of the other thread. It looks to me like the original engineers actually did some pretty good work.

Thanks Tom, there seems to be a lot of intrest in this! And you are right I think for what it is they made a very good turbo that's hard to be improved upon

 

[skew12]

Well this saved me some money!

 

[ToMang07]

Good call splitting this into a new thread...this should be much easier for people to find! :thumbup:

 

[Tom S]

Dyno Run - 04/17/2012 - GTP38R, 1.0 W/G housing, Stock compressor wheel
(All values rated at 3500 RPM)

• Max Boost - 34 PSI
• Max EBP - 47 PSI
• Max EGT - 1300
• Peak HP - 566 @ 2613 RPM
• Peak TQ - 1189 @ 2512 RPM

Dyno Run - 04/17/2012 - GTP38R, 1.15 Non-W/G housing, Stock compressor wheel
(All values rated at 3500 RPM)

• Max Boost - 34 PSI
• Max EBP - 45 PSI
• Max EGT - 1300
• Peak HP - 542 @ 2620 RPM
• Peak TQ - 1141 @ 2433 RPM
• Net HP Loss - 24 HP
• Net TQ Loss - 48 Ft./Lbs.

(click on image to enlarge)

Bill, how well is the truck loaded on your dyno compared to on the street? I think you have a Mustang Dyno if I remember right. How many seconds would you estimate the run lasted, I am curious about the EGTs is why.

 

[lincolnlocker]

awesome setup and numbers guys...

 

[Power Hungry]

Bill, how well is the truck loaded on your dyno compared to on the street? I think you have a Mustang Dyno if I remember right. How many seconds would you estimate the run lasted, I am curious about the EGTs is why.

The dyno is running a simulated load of 8500 Lbs., runs are in 3rd Gear with the T/C locked, and the 2000 RPM sweep takes about 9 seconds. I can run a heavier simulated load which will extend the dyno time to around 15 seconds depending on the load.

 

[CSIPSD]

I had horrendous surge with the 1.00 housing and my 38R. Installed the 1.15 and no more surge.

My 38R has over 250k on it now, with 140k of that with the 1.15 housing.