Our 6-speed Project
03-01-2013, 10:54 AM
#20
Rennlist Member
I get to drive a Gen2 with mild mods on a frequent basis on the track, and you will need a monster 928 to keep up with it... The fact that the car/engine/drivetrain combo is idiot proof is an added bonus... Don't knock the only real American supercar...
But I agree - a Porsche needs a Porsche engine...
BMW V12s are pretty rubbish... BMW ///M V10s or V8s are a different kettle of fish altogether...
03-01-2013, 11:20 AM
#21
Developer
Thread Starter
Please let's not take the thread in to the direction of a discussion about V12's or Vipers.
Start a new thread if that's what you want to discuss.
Thank you.
Start a new thread if that's what you want to discuss.
Thank you.
03-01-2013, 11:30 AM
#22
Rennlist Member
Good luck with the project!
Can you tell what the ratios + final drive are of the 6spd transmission. Wonder whether it would benefit 5spd owners with street cars - my GTS is turning 3000rpm at 130km/h, which is too high and hurts fuel consumption. Wondering whether a 500rpm drop would not help as there is more than enough torque anyway...
03-01-2013, 11:32 AM
#23
Developer
Thread Starter
Good Luck! Can't wait to see how you will do this. I bet they sell like Hot cakes!
Best of luck to you with your 6-speed setup also. From the look of your thread (which I will not post on) you are way ahead of me.
You have them in car(s) and I just got started. Our finished solutions for the various problems encountered in this swap are probably going to be quite different.
Thank you for your PM, I am going to answer that too.
Last edited by Carl Fausett; 03-01-2013 at 12:54 PM.
03-01-2013, 11:44 AM
#24
Developer
Thread Starter
I see the prospective purchaser for a kit like this to be either:
a) 928 road-racers
b) super-928's... guys above 550 lb/ft of torque who are breaking their trans
c) owners that just want a 6-speed.
When I look at group A and B above - I don't really think the market for this upgrade is that large. At the current price for a good used G28-13, I think I can get this group into a M12 trans-axle swap for about even money.
It will put an end to their breakage, and open the door to use upgraded and less expensive after-market parts. The C5 can be built out to handle 1200 HP
Transzilla says: http://www.rsgear.com/products/trans...smissions.aspx
But still, Group A and B is a very small group of 928 cars/owners.
As to group C, guys who don't need one, they just want one: price and ease of installation is going to control whether they get in the boat or not.
a) 928 road-racers
b) super-928's... guys above 550 lb/ft of torque who are breaking their trans
c) owners that just want a 6-speed.
When I look at group A and B above - I don't really think the market for this upgrade is that large. At the current price for a good used G28-13, I think I can get this group into a M12 trans-axle swap for about even money.
It will put an end to their breakage, and open the door to use upgraded and less expensive after-market parts. The C5 can be built out to handle 1200 HP
Transzilla says: http://www.rsgear.com/products/trans...smissions.aspx
But still, Group A and B is a very small group of 928 cars/owners.
As to group C, guys who don't need one, they just want one: price and ease of installation is going to control whether they get in the boat or not.
03-01-2013, 11:55 AM
#25
d) someone like Dinsdale that was tired of the "synchros"
e) someone like xschop that that was bored, designed and machined all the custom parts, then decided he wants an auto so wifey can drive it.
e) someone like xschop that that was bored, designed and machined all the custom parts, then decided he wants an auto so wifey can drive it.
03-01-2013, 11:58 AM
#26
Developer
Thread Starter
Can you tell what the ratios + final drive are of the 6spd transmission. Wonder whether it would benefit 5spd owners with street cars - my GTS is turning 3000rpm at 130km/h, which is too high and hurts fuel consumption. Wondering whether a 500rpm drop would not help as there is more than enough torque anyway...
Note both 5th and 6th are over-drives in these transaxles. Taller Final Drive Ratio also. And closer-ratio gearing in the gears under 4th that the racers will like.
Also note that the trans and the diff use different fluids now. IMHO that's always been a problem for those who want to race the current trans. The viscosity needed to protect the ring and pinion from wear is too heavy for the trans if performance shifting is your goal. It probably didn't matter to the OEM 'cause the 928 was a touring car.
But now, with Dexron III in the trans (synthetic, slim film, quick and easy shifting) and hypoid only in the diff - the T56 is going to shift quicker and more easily than the G28-13
Then there is the "hard to shift when hot" issue that the racers encounter that should be also solved by this.
...and the drive-shaft breakage on the racers and/or the high torque cars. This upgrade would also address that issue as well.
Last edited by Carl Fausett; 03-03-2013 at 01:33 PM.
03-01-2013, 01:12 PM
#28
Electron Wrangler
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Carl - Nice plan - I will watch with interest - nice to have more/various options.
Will you be considering offering chevy autoboxes too?
Alan
Will you be considering offering chevy autoboxes too?
Alan
Last edited by Alan; 03-01-2013 at 03:09 PM.