Looking for a Turbo suggestion

Buickrat

Member
Joined
Jul 23, 2010
I am building a street/strip car and I am at the point of purchasing a turbo for the car. I would like to drive it on the street some what daily and turn high 9's to bottom 10's at the track. The car is 10:00 compliant for any NHRA track, 3600 pounds with the driver, here is my combination.

0153 STG2 Block
274 inch stroker w/9.0 compression
TA CNC ported SE Aluminum heads
Champion CNC ported intake with a 70mm TB
220/224 Roller cam on 114 LSA
TA headers with a TH Down pipe
3400 stall 9/9.5 torque converter/ not purchased yet leaning towards PTC

Looking for advice on turbo selection, looking for a turbo with quick spool time, internal or external waste gate? I am open to changing down pipe if needed.

Thanks
 
If you're looking at the new stuff the smallest I would buy is a Precision billet 6768. The billet 7168 would be the next and my personal choice. Various older models can get this done but with a mean motor like that you should run 10.0 9.90s with under 30psi. Putting. Smaller units than above may turn your driving experiences into tire blazing pedalfests.
 
My first choice was the 6768 DBB CEA but when I called Precision they suggested a 7675 DBB CEA, they were worried about to much exhaust back pressure with the Smaller tubine housing, they then stepped it down to a 7175 DBB CEA. The turbine AR is .81 on these two turbos I am a little concerned with spool time but, I do understand their concern with excessive exhaust pressure. What are your thoughts on that? Do you believe I need to go to a T4 flange with a external waste gate or stick with the T3 internal WG?
 
You can accomplish your goal with a 3 bolt Precision .85 Buick housing. If you do not have headers or a downpipe yet you can go the 4 bolt housing and external gate route. If you were talking to Pete Barton or Patrick Rubio follow what they say. They are far more experienced in Turbo Buicks than the other people that work there. I know of the 7675 which I would feel is over kill for your goal. The 7175 is not a bad suggestion but I didn't think to add it in my previous post because I didn't know if you were open to going to a four bolt, and v-band downpipe. I use the RJC mega puck on my ATR 3" internal gate downpipe. If you put the 7175/7675 four bolt on and you don't like the spool up, you won't be happy to say the least.
 
I found out Yesterday that Patrick is no longer with PTE and Pete was difficult to get on the phone. I spoke to another individual that seemed somewhat knowledgable but he had to keep putting me on hold to ask someone else the questions.
 
I found out Yesterday that Patrick is no longer with PTE and Pete was difficult to get on the phone. I spoke to another individual that seemed somewhat knowledgable but he had to keep putting me on hold to ask someone else the questions.

That may be the guy I told to have Pete or Patrick call me when they have time. He offered to help me but after a few trick questions I knew talking to him was a bad idea.LOL Once you install it, it's yours!! Thats the tough part. When do you need the turbo by? Do you have a headers and a downpipe yet?
 
I would like to drive it on the street some what daily and turn high 9's to bottom 10's at the track. looking for a turbo with quick spool time
There is no need to go larger than a 6765. That will run down well into the 9.50-9.60 range. You have a lot more engine than you need for that goal. You could have went smaller on the cam and had more vacuum.
 
I do have a TH down pipe, I can always sell the TH pipe and go another way. I have a set of headers on hold at TA so I can change my order to accomadate a T3 or T4. I believe I have narrowed it down to a 6768 CEA, 7168 CEA or a 7175 CEA. It's just a mater of deciding to run a T3 or T4, internal or external waste gate and a TH type down pipe or a V band type down pipe. I am mostly concerned about spool time I do not want a pig out of the gate.
 
Bison do you see any concern with back pressure with that size of turbine wheel? Should I stick with the T3 with internal waste gate set up and run a a TH down pipe?
 
The cam has not been ground yet my thought was 220 @ .050 on a 114 LSA, the came will have a negative 4 to 6 degrees of overlap at .050 what would be your recommendation? The car will weight about 3650 with me in it.
 
LOL 6765/6766....car will feel like its on 215/65/15 in the rain. May as well get an engine management system with traction control!! My CEA 6765 would flash from 10 to 30 psi in one second on a 8.5:1 231 with ported irons. I would laugh at it on a engine like Buickrat has. Too small! It fits Bent6's combo very well and he is almost in the nines so I do believe it can make nine second power without a doubt. However, under turbo the car and its no fun either.
 
Bison do you see any concern with back pressure with that size of turbine wheel? Should I stick with the T3 with internal waste gate set up and run a a TH down pipe?
To put it simply I know of someone with a 9:1 stock stroke that just made 9.7-9.8 power with a 6265 at less than 30psi. The turbo wasn't done at the boost it was dynoed at either. Less duration than you are running and a 3.5 TH style dp with internal gate. I would run an off the shelf 212 before I ran anything like you suggested for a street car that will be driven almost daily. Even though that engine will easily make more power with a custom solid grind with duration in the mid 220's with more turbo than I suggested you're only Looking for high 9 sec power. The instant you put a larger cam with a heavy turbine the fun factor goes in the crapper. Go with a 65 or 66 trim ex wheel and the 67 compressor and plan on running no less than 25psi on the internal gate setup. If you want to run less boost go with the 62 compressor and open the wastegate hole to 1.1". I'm typing from something that has been done already. Not a coulda would shoulda. You will need a custom dp and external wastegate to run less than 25psi on that engine with anything larger than the 6766. The compressor will move a lot higher mass flow atnlower shaft speeds than you would think.
 
If you go with an external gate and dump it you will see less backpressure than an internal gate housing. Also going with a t4 style setup will have more turbo options like bullseye or borg warner.
 
LOL 6765/6766....car will feel like its on 215/65/15 in the rain. May as well get an engine management system with traction control!! My CEA 6765 would flash from 10 to 30 psi in one second on a 8.5:1 231 with ported irons. I would laugh at it on a engine like Buickrat has. Too small! It fits Bent6's combo very well and he is almost in the nines so I do believe it can make nine second power without a doubt. However, under turbo the car and its no fun either.
He wants to run low 10's high 9's. A 6765 will run a half second faster than that. How do you figure it's under turboed? Imo it would be over cammed for his goals if he went with the cam he's thinking about. He needs about 700hp to run the number.
 
He'd run the number with the 7168 or the 6768. What wrong with using those? You used a 6680 on your black car when you wanted nines right. Less back pressure with the q-trim wheels correct right? Spooling will not be an issue for him.
 
LOL 6765/6766....car will feel like its on 215/65/15 in the rain. May as well get an engine management system with traction control!! My CEA 6765 would flash from 10 to 30 psi in one second on a 8.5:1 231 with ported irons. I would laugh at it on a engine like Buickrat has. Too small! It fits Bent6's combo very well and he is almost in the nines so I do believe it can make nine second power without a doubt. However, under turbo the car and its no fun either.

You should drive a cobra running a kb or whipple @ 20+ psi, 4.11 gears,a 28" drag radial, making 600rwtq as soon as the pedal is on the floor. Boost is instant and full is as soon as the throttle is 3/4 of the way depressed. Instant boost is amazinglly fun for a street/strip car.

I would choose the 6766 t4 housing and choose which ex housing depending on where you want the car to make boost. There is always the option of going with a .96 t4 if spool is to fast. But if it were mine I'd go with the .81ar because I like the instant boost.
 
Like this one... Me driving my friends 03 Cobra. Has my old 400 in it. I know what you guys are saying and I'm not saying you're wrong. It would be a different thing if he had a 6765/6766 already.
 

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Looks like a lot of fun;) and I also get what your saying. Since he hasnt bought the turbo why not go big to begin with. I agree with what that. But for a street/strip car I'd want a happy medium for something that'll spool quick and make the power to run the number.
 
LOL, I currently own a 2008 Bullit mustang that has a Whipple on it running 18 lbs of boost and making 624 ft lbs of torque at the rear wheels, the car runs 10.80's @ 130 mph with 60 ft times a good as 1.49 with both wheels in the air ( only a couple of inchs) with 3.73 gears in the back and 26.5 MT Drag radials on the factory Bullit wheels weighing in at 4000 lbs with me in it. Put a point and steer guy in a stick car, that is funny to watch. I have always been a Buick guy so I am getting back to my Buick roots and putting a GN together. Trying to cut my teeth on the turbo V6's now. I have owned plenty of Buick big block GS's including the old Kenne Bell STG 2 car which I was able to get in the bottom 10's in the early 90's
 
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