68 Gtq Bb

[68 drop top]

Any thoughts on this Turbo?
109 w/ caps and pistons, GN1 alum. heads, 214/210 billet roller, cottons f/m, dual razors, will have a new Tweak chip, twin walbros, currently 60lb mototrons but will switch to larger if need be, 3200 stall, standard weight car.

thoughts on the 68 GTQ BB compared to the 6776 bb that many people seem to be running on here?

My personality would lean towards the best performance, sacrificing some street manners if I had to.

Thanks,
Jason

 

[RUQWKNF]

A long time ago, in a galaxy far, far away, PTEs 70 turbo actually used the 68mm inducer, T series compressor wheel. (Circa 1996-1999) It likes to run in the 22-30psi range to make decent power, when coupled to a GT-Q turbine wheel, it would only be about 20-25hp shy of what a TSM legal 70 GT-Q turbo could support.
Comparing this to a 6776R turbo would be as follows,

6776R: Depending on compressor cover and turbine housing it is spec'd with, it will support between 765 - 780 flywheel hp. With the Buick .63 three bolt PTE turbine housing on a 231-235 CI motor, it really likes a converter that can stall to 3200 at zero psi.

68 GT-Q: In all fairness, it should support anywhere between 825 - 830 flywheel hp when maxed out. The 68mm compressor wheel has been around a very long time and unless there has been a recent change with the design and or they've started using a different wheel, the old 68mm wheel was not of GT lineage. It is considered an older T series compressor design. It would most definitely have the same converter requirements as a 70 GT-Q in the journal bearing version, in the dual bb version, the stall requirements should be in the 3500-3600 range at zero psi.
HTH

Patrick

 

[68 drop top]

A long time ago, in a galaxy far, far away, PTEs 70 turbo actually used the 68mm inducer, T series compressor wheel. (Circa 1996-1999) It likes to run in the 22-30psi range to make decent power, when coupled to a GT-Q turbine wheel, it would only be about 20-25hp shy of what a TSM legal 70 GT-Q turbo could support.
Comparing this to a 6776R turbo would be as follows,

6776R: Depending on compressor cover and turbine housing it is spec'd with, it will support between 765 - 780 flywheel hp. With the Buick .63 three bolt PTE turbine housing on a 231-235 CI motor, it really likes a converter that can stall to 3200 at zero psi.

68 GT-Q: In all fairness, it should support anywhere between 825 - 830 flywheel hp when maxed out. The 68mm compressor wheel has been around a very long time and unless there has been a recent change with the design and or they've started using a different wheel, the old 68mm wheel was not of GT lineage. It is considered an older T series compressor design. It would most definitely have the same converter requirements as a 70 GT-Q in the journal bearing version, in the dual bb version, the stall requirements should be in the 3500-3600 range at zero psi.
HTH

Patrick

Thanks for the info Patrick. If I'm understanding you correctly, I should be patient and wait for the 6776R parts to come off back order and get that over the 68?
Would you know what number I should order for the standard 3 bolt flange with a 4" inlet and a 3" terry houston style d/p outlet?
Thanks again for the great reply :smile:

 

[Quick6'n'-K.C.]

Jason-

http://www.turbobuick.com/forums/turbos-turbo-related-parts/226458-6776bb.html

There is a link in that thread to another member running a 6776rs