School Me On Garrett BB Turbos

[kuntryboy369]

i have been beating the bushes trying to find a turbo. i had my heart set on a super b special. but after a look at the gt3788r, im leaning that way now.(the gt4088r and gt4094r caught my eye too)

the problem im having is i just cant get the numbers to make since.

a super b special is a 64.5/71/14 and will flow 1160cfm (80.4 lbs/min). its rated at 375-525hp.

a gt3788r is a 63.5/72.5/1.11 and will flow 69lbs/min (1000 cfm). its rated for 440-675hp.

i know the schwitzer s300's are a top knoch turbos, and im not knocking them. i just dont understand how the super b special will flow that much more that a garrett of similar size. i would assume that since the garrett is a ball bearing turbo it would be more efficient, and would get infront of the fuel faster. therefore you would need less turbo to do the same amount of work. so i can understand the hp rating. i just dont understand the flow rating.

any help would be awsome! :thankyou2: :Cheer:

 

[kuntryboy369]

sorry, i ment to post this in the dodge comp and preformance section.

mods, feel free to delete this thread.

 

[Hammer]

GT88R is not a 63.5/72/1.1a/r

the GT3788R Stage 3(which is their biggest diesel application charger specs are as follows......

Turbine Hsg A/R 0.99
Comp Whl mm/trim 88/52
Turb Whl mm/trim 72.5 / 78

They claim it will support 550hp/1200tq and I can honestly say after thrashing mine to death for over 2 years the best I got out of it was 493hp/1100tq.When the charger lit the game was on but it ran out of energy early and was done when the truck wanted to make power.It would make a great street charger or a charger for the under 500hp crowd but it lacks bigtime on the top end for airflow.Also note that Garrett's stupids "power elbow" is a restriction that makes drive pressures go through the roof and for you to make any safe power with it you will need to have a HX40 style flange made and have it ported to match the walls of the exhaust housing.

If your looking for power then stick with the 64/71/14 from one of the bigger manufacturers of quality S300's you will be way better off in the long run.....Andy

 

[Scooter's Roofing]

most garrett power estimates are gasser power numbers... a borg warner ETT wheel will move more air than an equivalent sized Garrett wheel

 

[kuntryboy369]

GT88R is not a 63.5/72/1.1a/r

the GT3788R Stage 3(which is their biggest diesel application charger specs are as follows......

Turbine Hsg A/R 0.99
Comp Whl mm/trim 88/52
Turb Whl mm/trim 72.5 / 78

They claim it will support 550hp/1200tq and I can honestly say after thrashing mine to death for over 2 years the best I got out of it was 493hp/1100tq.When the charger lit the game was on but it ran out of energy early and was done when the truck wanted to make power.It would make a great street charger or a charger for the under 500hp crowd but it lacks bigtime on the top end for airflow.Also note that Garrett's stupids "power elbow" is a restriction that makes drive pressures go through the roof and for you to make any safe power with it you will need to have a HX40 style flange made and have it ported to match the walls of the exhaust housing.

If your looking for power then stick with the 64/71/14 from one of the bigger manufacturers of quality S300's you will be way better off in the long run.....Andy

the garrett site said the stage 3 was the specs i listed above. aparently i read something wrong. im quickly finding out id have to step it up to a 4097r to get the 600hp im shooting for. the reason the 3788r appealed to me because it would supposedly support ~600hp. and i can hang a s475 or s480 under it later if i go crazy with it. but i guess a super b or s300 would be the better way to go. its cheeper and make more power.

 

[Hammer]

I often thought about making my old GT3788R into a set of twins due to how well it spooled up but couldn't get the nightmare of the water cooling lines out of my mind.See Garrett uses the water cooled center section to allow for faster spoolup and when you use that feature you run a restricter in the oil feed line to facilitate this.I tried running mine without the oil restricter and it slowed the charger down alot and never helped the top end at all.So instead of having a plumbing nightmare I just sold mine to a member here who still runs it and loves the way it works and went with a S300 variant from HTT.