T5 advice : WC or not to be... WC?

[Jeff Brock]

Hey folks,

I am starting a "new" Buick XO / GCC project for the salt.
Using the Buick big block 325, 280 hp @ 5000rpm.
I have ran the Borg Warner T-10 and now running a Muncie 65 c.r.

I am considering going to a 5 speed T-5 . I have a couple T-5's  that are not the WC.  Any advice about the difference or the use of the T-5 in LSR?

Thanks
Jeff Brock

[thundersalt]

Need HP to pull an overdrive. We went from a wide ratio toploader to a richmond 5 speed keeping 5th 1:1 with 3rd, 4th, and 5th close ratio for minimal rpm drop.JMO

[Jeff Brock]

Yes I agree. 1:1 at 5th & c.r ,  using the I-8 h.p.

I just have NO previous experience with a T-5 {or any 5 speeds}.
are WC T-5's  all o.d. @ 5th ?
Is a Richmond a better trans than the T-5 ?

[tedgram]

Yes I agree. 1:1 at 5th & c.r ,  using the I-8 h.p.

I just have NO previous experience with a T-5 {or any 5 speeds}.
are WC T-5's  all o.d. @ 5th ?
Is a Richmond a better trans than the T-5 ?

     Most are, but you can get different ratios. Don't know about Richmond.

[Buickguy3]

   Jeff,
   We used the T-5 WC in the Salt Cat last year, and the high torque of the old straight 8 took all of the teeth off of 3 rd. gear on a test run here in Montana. We replaced it with a Tremec TKO 600 and that has been working very well. The Richmond is a step up, but a little more expensive. In my opinion, the T-5 WC is marginal in your application. Nice to see you at WF.
   Doug

[Richard 2]

Jeff
We started out with a tremec 6 speed with a 4:10 gear hit a wall (couldn't go any faster) at 200 mph in 5th gear. Then we went to a G-Force 101 4 speed with a 3:00 gear went 222 mph and climbing.   

[Jeff Brock]

   Jeff,
   We used the T-5 WC in the Salt Cat last year, and the high torque of the old straight 8 took all of the teeth off of 3 rd. gear on a test run here in Montana. We replaced it with a Tremec TKO 600 and that has been working very well. The Richmond is a step up, but a little more expensive. In my opinion, the T-5 WC is marginal in your application. Nice to see you at WF.
   Doug

Don't you just hate it ... when you have several of the "marginal" parts laying around.  The big Buick and I took {ate} 2nd gear out of the T-10 last fall at the Albuquerque Drag strip and we took 3rd gear out of the Muncie c.r. on our last run at World Finals on the 9th.
I guess I better start shopping.

[GH]

Jeff, I'll sell you a Jerico 4 speed with a Gearvendors OD that will hold 849 lb ft of torque at the rear wheels and I will throw in the whole car.

[Jeff Brock]

GH , 

boy, this tranny shopping is easier than I thought. I'll take the Jerico and I'll make "relative income" payments on the balance .
If you agree... we better be freinds for a loooong time.

Lets go fishin!

[38flattie]

Hey folks,

I am starting a "new" Buick XO /SVGCC project for the salt.

Umm, What's that? Do yo mean BVGCC, or am I missing something?

[Jeff Brock]

Jeff
We started out with a tremec 6 speed with a 4:10 gear hit a wall (couldn't go any faster) at 200 mph in 5th gear. Then we went to a G-Force 101 4 speed with a 3:00 gear went 222 mph and climbing.   

Richard,
I have stewed on you post for a couple days.
I guess there are a lot of formula relativity items missing for me to grasp much {i.e. rpm shift points, gear spread ratios, h.p. ect} . But I am most currious as to why you changed out both the trans and the gear?  or did you try the 6 speed with the 3.00 ?
4:10 to 3:0 is a big jump.
I am real limited in rpm's , with my 41.5" long crank {5500-6000 max}
with the frontal area of a small house. My thinking is more , closer gears

[Rex Schimmer]

Jeff,
I would avoid the T5 as it does not have the torque rating that your big straight 8 can probably put out and there are to many 5th gear options that will not work well for racing, to big of a step. I would suggest looking at some of the NASCAR surplus sites as they have "race proven" NASCAR trannies for very reasonable pricing, $1500, and will usually provide any gear ratio you want in any gear.

Rex

[38flattie]

Rex is right. Even a WC is only rated for 300 ft/lbs. A Muncie is far stronger. If you're just looking for strength, until you spend the bucks for a 1:1 five speed, look and see if you have a Mopar 833 laying around. If you're really lucky, you'll have a 71-74, which is close ratio, and very strong.

I'm going to use one, because I'm to cheap to buy a 5 speed.

[Jeff Brock]

well thanks folks, this is the info I was after . I'll leave the T-5 alone. I did the simple T-5 5th gear input / output rotation check this eve , and they are o.d. trans's anyways. Not for this build!
I have "lunched" 2 fairly respectable, well re-built  4 speeds already.
Buddy, I'll look into the 833. It just so happens that in a strange dark corner of the studio... there are 2 or 3  833's. I did not know they were stronger than a Muncie.
I am leaning towards more gears, closer ratios with 1:1 top, though.
I'm currious about Richards Tremec 6 and G- force 4 experience.
I think I need to compile the shift ratio data from the transmissions I blew.
The T-10 w.r. gear spreads and the Muncie c.r. gear spreads and find a stronger trans that splits the difference in a 4 speed or speads it more even in a 5 or 6 speed.

[thundersalt]

On a side note: If you end up with an external shifter trans do your self a favor and use a Long shifter and not a Hurst. We found out the hard way that Hurst ain't what it used to be and pricing is about the same.