GTFORMULA

iTrader: (94)

I need to know what power levels a fully built 6 speed can handle. I already had one hond up to 700 rwhp but will it hold 1000 ,900,800 ? Experts only please I need real world experience.

NOSjohn

iTrader: (9)

Give T56Rebuilds.com a call and talk to Joe or Amber. They can give you an EXACT idea as they've built many of the T56 transmissions for big power Vettes and Vipers.
Their telephone is:

(888) 937-4411

GTFORMULA

iTrader: (94)

Thanks john. Also was going to contact you about my turbos I got from precision. I believe they will be too small for my setup. what turbos do you recomend for 1000 rwhp on a mostly drag car. 370 cid 226 cam and ported ls6 heads. I know you need more info but any rough ideas.

NOSjohn

iTrader: (9)

Off the top of my head, you'll need at least a 63mm wheel on each but with a 370c.i. motor it may not meet the demand a 370 requires (falling off the choke line). I would say at least 66 or 67mm wheels on each turbo will safely get you there without going off the map and staying inside the choke line of the turbo.

GTFORMULA

iTrader: (94)

how much would a 67mm cost? I will need 2 with t-4 flanges and 3" v-band exhaust to bolt up. I asked Jose at forced inductions the same thing and he recomended twin 57mm upgrade for the turbos I already have. I believe the 67mm would be better cause I dont want huge low end boost I will leave on a 2 step with 6000 rpm launch. Shifting @ 6800 with 6 speed all the way through.

NOSjohn

iTrader: (9)

What size turbos do you currently have? Depending on the size, you may certainly hit near the goal but may need big big boost numbers - upwards of 25+ psi. It's tough to say without knowing all the information.

A 67mm turbo can run, depending on manufacturer (top 3) and the housing sizes, around $1300 to $1700+. I haven't heard much feedback on these eBay turbos, so I'm not so sure I would use something like those...in case someone asks.

GTFORMULA

iTrader: (94)

No I have precision 44mm inlet 57mm out . .68a/r exhaust .60 a/r inlet. They were with the kit when I bought it for a stock motor. Well plans have changed and i know these things are too small for the kind of power I want. I dont want instant boost I need something that will get full boost at 4000 to 6800 shift. also not have the power band fall off too early like when a turbo is too small.

NOSjohn

iTrader: (9)

Hmm, the 44mm inlet/57mm out has me confused. What did Precision refer to them as?
Maybe they said 44mm compressor exducer / 57mm turbine exducer?
Either way, they sound small, if you're looking at the goals you have in mind, you'll need to go bigger.

BUYAMERICAN

A well built six speed tranny will hold about 900-1000 rwhp. You will absolutely need the best mainshaft. I would very, very surprised if you hit eights. The two guys that have had the power, besides me have now gone powerglide and Th400. Both broke their mainshafts. Paul spent $30k just in broken drivetrain parts in one summer.

60-67 turbos.
67's will take you to about 1150 rwhp at 22 psi.. with a good setup on 116.

GTFORMULA

iTrader: (94)

The part number on the turbos is PTB 300-4476.

Maybe that would help. I know it will be hard to hit eights but if I do it just once Ill be happy. Then I will just run nines all day in the heat. The convertion the an auto is way too much money so I have no choice but to stick with the 6 speed.

Any clutch ideas ?

BUYAMERICAN

SPEC 5
Cartek VII. At this hp. level, you will not even get a weekend out of it.
Tilton Triple. $4,500-$5,200

Have your machine shop re-balance the assembly.
SFI Blanket or Trans shield a must have.

NOSjohn

iTrader: (9)

PTB 300-4476 : Those are the PT-44/TE-44 4476E turbo with a T4 Tangen and .63 A/R turbine housing. They are rated to about 580hp, a little inflated IMO. I've personally seen that turbo make 400-425rwhp. With two of these, you will be very hard pressed to hit your goal...IMO.

I'm also not positive a set of T-67's will fit in the existing location of the kit you have. You may want to call them and ask. Again, something in the 63mm-67mm range will get you to your goal easy...just a matter of keeping the drive line together.

Call, if you like, if you have more questions to address.

allngn_c5

iTrader: (3)

Damn, that sounds like one hell of a beast you are building. Good luck getting it to hook.

GTFORMULA

iTrader: (94)

It will be a challenge. Im planning on 28x12.5x16 etstreet's.

Cajundude

iTrader: (7)

I'm putting 800 through the stock M6 tranny. We'll see how long it lasts.