W8 and Corvette Transaxle?

I assume this was somewhat toung-in-cheek, but.....

I could not disagree more. I know my SVT-Cobra is a totally different animal, but the gear ratio math is not that different. Most tranny ratio combos keep 4th gear at (or pretty close to 1:1), so most would agree that you really need 4 good gears for around-town, light to light driving.

So in a T-56, you have two OD gears. (a .80 and .62) The 6th gear (.62) Is really just a cruising gear and not a very good accelloration step up from 4th gear (1.0).

So.. If you are trying to accelorate aggresively past 65mph you really need the extra gear. IMHO

My 04 cobra accelerates just fine in 6th gear afte rabout 30mph, lol

Anyways, 5 and 6 speeds are over-rated ..... either 1 or 2 more useless gears that can break. 4 speed FtW :D
 
I compiled the attached G50 Spec sheet to help me select my transaxle. Most of this info was pulled from Gbox.com. I hope this is helpful to others as well.
What is not included on that list are two of the more relevant topics being discussed regarding transaxles...weight and strength.

There are a few G50 variants with a 9" ring gear vs. a 7-1/2" ring in most of them. This includes both 5-speed and 6-speed boxes. It is a no-brainer that the 9" is a more stout unit but it does come with a ~10lb. weight penalty. Most, not all, of the 5-speed boxes have the 7-1/2" ring gear. Most, not all, of the 6-speed boxes have the 9" ring gear. There is also an additional weight penalty of ~25-35+ lbs for the 6-speeds due to the extra gearing and the larger case to accommodate it.

The Ricardo box is near 200 lbs. iirc (20-45 lbs. heavier than Porsche varants) but someone else needs to confirm or update that info.

All of the Porsche 6-speed boxes have a useless granny 1st gear for the V8 crowd. Of course that and others can be swapped unless you want a granny gear for trolling around in pit row.

The best, most relevant info regarding Porsche boxes.
California Motorsports Kit Car section - FFR GTM Ultima GTR GT40 inverted Porsche transmission transaxle
 
out of all of the porsche 6spd boxes, this one seems to have the more reasonable ratio's out of the box for a v8 from gbox website. don't know if this is a 9" or not. Also, don't get the 4th/5th split at all, seems minimal.

G97/88

997 GT2 2007-09
6-speed fully-synchronized transaxle
Manufactured by Aisin
Plate-type limited-slip differential
Cable shift
Single-plate clutch
Oiling system with cooler
Gear ratios:
1st gear: 3.15
2nd gear: 1.89
3rd gear: 1.40
4th gear: 0.91
5th gear: 0.89
6th gear: 0.73
Ring and pinion: 3.44
 
I continue to point to the mostly disregarded 930 as a very good option...

Mmmm :)

I vote 930. Mmmm, 930 transaxle.

6 gears are over-rated ... it's just just more useless stuff that can break :D


Honestly, with how I drive and knowing what I know now, if I were building another SLC I'd use a 930. Light, strong, small, perfect. I'd trust it more than a G50 with a V8 and be way more comfortable with it than a Ricardo (sorry, it may be a great transmission but it's heavy and you're f*k'd if you break it)
 
out of all of the porsche 6spd boxes, this one seems to have the more reasonable ratio's out of the box for a v8 from gbox website. don't know if this is a 9" or not. Also, don't get the 4th/5th split at all, seems minimal.

G97/88

997 GT2 2007-09
6-speed fully-synchronized transaxle
Manufactured by Aisin
Plate-type limited-slip differential
Cable shift
Single-plate clutch
Oiling system with cooler
Gear ratios:
1st gear: 3.15
2nd gear: 1.89
3rd gear: 1.40
4th gear: 0.91
5th gear: 0.89

6th gear: 0.73
Ring and pinion: 3.44
There is no way that is correct. Fourth gear is probably 1.1 or thereabouts.
 
what's the 930 cost with the right gears for v8 torque?

~$12k complete (i.e., rebuilt, inverted, cv joints, starter, ring gear, flywheel, clutch, pilot bearing, all bolts, shipping)

Which is basically identical to a complete package Ricardo or G50.

So far the lesson I've learned about transaxles is that they all cost about the same out the door to get 'er done.
 
Yup, a 4 speed with wide ratios. Perfect for a light GT-40 with good torque numbers.

BTW, two of the largest 930 builders are in Boulder, CO.

GBox and Carquip
 
So the 930 seems to be underrated and could be a good option if you can get past 'only' having four gears and not being power crazy.

A quick Google suggests the weight is anywhere between 120lbs and 135lbs...

I need to give Griffin/Mendeola a call and find out what theirs weigh in at.
 
I have had the Pantera ZF, the G50 and the Ricardo in 5 different chassis. Unfortunately, I did not weigh them. The ZF may have been the lightest, the G50 was at least 150 lb and the Ricardo was at least 200 lb. The Ricardo is huge! The use of it really hampered designing a rear diffuser - it mated to LS7. Race boxes like Mendeola, Hewland, etc., can take the abuse - for a short time. Their gears are not typically hardened (so they are not brittle) and wear out quickly. They will also not have synchos (a bonus imo) and can be VERY noisy - even at idle.

I would lean toward the G50. There are a lot of upgrades available. I had the ring gear flipped (with proper oiling changes) and a Torsen LSD installed and spent less than on the Ricardo.

As for H patterns and clutch pedals, when you drive really fast stuff, the time to shift becomes a large percentage of acceleration time. Both are becoming relics, but for the time being the stuff is not cheap or readily available for V8 mid engined apps. I'm wanting a short light 6 speed paddle shift transaxle that can handle 1000 hp. It has to be cheap too.
 
As for H patterns and clutch pedals, when you drive really fast stuff, the time to shift becomes a large percentage of acceleration time. Agree, if you're shifting.. you are not accelerating.

I'm wanting a short light 6 speed paddle shift transaxle that can handle 1000 hp. It has to be cheap too. Me too - I'm also waiting for a young Raquel Welch to come knocking on my door and invite me to live on a remote island.
......
 

Dave Lindemann

Lifetime Supporter
My Ricardo is still as delivered from Fran - I'll try to weigh it tomorrow. The box is HUGE but I can lift it so I question the 200-lb+ estimates but I could be wrong.....

Dave L
 
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