Opinions/experience on bb gt3788r

[TFaucette]

I have a 3788r lying around and considering using it on my 06 however I am looking into using a smaller stage two turbine housing on it, I tow heavily with the truck sometimes so I am looking for stock like spool up yet support up to 600hp. I have heard that the 63.5mm gt wheel does not flow what a comparable bw will but can you change that with a batmowheel in one? And I would also love to hear opinions/experiences on the bb Garret's on a cummins altogether seeing as they're twice as expensive and far less common than all the s300's especially with one using a batmowheel

 

[AH64ID]

My understanding is you want to steer as clear of batmowheel as possible, no proved gains but lots of exploded turbo's.

I have a GT3782R Stage 2 on my truck and really like it. The GT3788R will be much better if you put the smaller turbine housing on it. The DDP tips and lower timing of the Edge will also help the spool.

I have had the GT3782R with 2 different cams, neither of them stock, but they both make it spool VERY fast and the current Hamilton 178/208 spools it as quick, or quicker than stock.

The BB turbo's are the way to go, they offer lower back pressure than most S300's and better spool. They are also water cooled which is great.

I tow around 17-18K GCW and it's a very good setup, especially since you own it.

 

[TFaucette]

do you think with the 3788r with stage 2 housing I will notice any extra lag over he351 without any other mods? and I need to update my sig I am now running a csp5 built trans tunes from phill

 

[AH64ID]

It will be a little slower to spool at low load but probably quicker at high load, but if you have EFI that should be an easy tune fix.

 

[jkidd]

the garrett bb turbos have under sized bearings for the diesel application and typically have smaller turbine wheels and are drive pressure limited. They are also expensive.

you have one, they spool quick, 600hp is a lot to ask of it.

 

[AH64ID]

the garrett bb turbos have under sized bearings for the diesel application and typically have smaller turbine wheels and are drive pressure limited. They are also expensive.

Can't talk much on the bearing size, but they are anything but drive pressure limited in my experience and in talking to others that use them as well. I can say bearing failure is very rare, everything I have found is that they are superior to JB.. except when a JB dealer is talking

I run 0.8:1-0.9:1 while towing and might hit 1.2:1 under heavy acceleration and higher rpms, thats DP:boost.

The turbine wheels can be a little smaller, but the exhaust housing is nearly always larger so the flow isn't hindered. The increase in flow thru the motor with this turbo was huge compared to the OEM turbo, considering very similar compressor flow rates.