3.9 RSR project --- my Carrera reborn

[9elf]

I like the way you think.

[Bill Verburg]

Originally posted by DW SD
Please fill me (us) in. I don't know boo about that transmission.

Doug

That was trans that I was going to buy until something more attractive came along, That is a 993RS trans, gearing will be just about perfect for for Teos mostly street engine/chassis: factory warranty, steel syncros, Porsche Motorsports 40/65 lsd, stiffer mounts, the second gear syncros alone were ~ $1500 a year ago.

The only thing better might be a /30 which is what I bought,

[911teo]

Originally posted by DW SD
Please fill me (us) in. I don't know boo about that transmission.

Doug

I think Bill is the authority when it comes down to brakes and transmissions....

I'll try...

The G50/31 is the transmission that came with the 993 Carrera RS.
It is a 6-speed transmission with close ratios.

For me it was the perfect choice. Rebuilding my G50 with short ratios would have been expensive. Plus the "special" gears that you have avaliable in the market place are fabulous for racing but noisy for a street car.

The G50/31 instead was build by Porsche with the dual utilization in mind. The syncros are upgraded from the standard 993 transmission (G50/20 and G50/21) and the ratios are closer.

It also comes with an LSD (i think we'll be able to change the locking properties... we'll need to check that).

These are the ratios of the transmission

1st = 3.154
2nd = 2.00
3rd = 1.522
4th = 1.242
5rd = 1.024
6th = 0.821

R&P = 3.444

With my engine (assuming redline @7,500) and my rear tires (305/35-17) these are the top speeds in gear

1st = 52
2nd = 82
3rd = 108
4th = 132
5th = 160
6th = 200


And these will be the RPM drops

1-2 2,734
2-3 1,787
3-4 1,375
4-5 1,312
5-6 1,487

Should be pretty sweet... Bill did I miss anything?

[911teo]

Check this link for more infos about the 993 transmission ratios

http://www.ultimabuild.com/transmission.htm



And yes, Bill gave me the heads up on the transmission I ended up buying! He's always there when I need to spend a little more money

[Bill Verburg]

It also comes with an LSD (i think we'll be able to change the locking properties... we'll need to check that).

The lsd is a Porsche Motorsports 40/65, non adjustable

Paul Guard has the edge in that and the strength deptartment.

i'll run the #s through my gear program for you

[Bill Verburg]

And yes, Bill gave me the heads up on the transmission I ended up buying! He's always there when I need to spend a little more money

Always glad to help

like I said that was going to be mine, I got the info courtesy of Bill H., who apparently likes to keep a very low profile but who is also building a very nice 993.

[911teo]

Originally posted by Bill Verburg
The lsd is a Porsche Motorsports 40/65, non adjustable

Paul Guard has the edge in that and the strength deptartment.

i'll run the #s through my gear program for you

I do have a Guard LSD....

We'll swap it when the Porsche one lets go.

[DW SD]

Good work fellas! VERY nice tranmission and information. Look for the gearing calculations - will be interesting!

Doug

[Bill Verburg]

Originally posted by 911teo
I do have a Guard LSD....

We'll swap it when the Porsche one lets go.

Me too

[DW SD]

Matteo,
WOW - what is that steel tubing bridge? A jig for welding in the camber plates? Holy smokes, that's a serious apparatus. Did they make that at their shop OR buy it?

Doug



[/B][/QUOTE]

[911teo]

Originally posted by DW SD
Matteo,
WOW - what is that steel tubing bridge? A jig for welding in the camber plates? Holy smokes, that's a serious apparatus. Did they make that at their shop OR buy it?

Doug

I am pretty sure they made it at the shop. These guys are very very good when it comes down to doing "special projects".

Another one of their expertise is building roll cages. There is a long thread on the racing forum about their approach.

Zuffenhaus - a rallye approach to cagework


I am going to have them build me a custom bolt-in roll bar.

[Mahler9th]

An interesting project. I have a '75 that weighs about 1950 and has a 3.8 single plug making about 360 bhp. Uses a 915. All likely a fraction of the cost of this project...

I drive it on the street, but it is not really in the "daily driver" category...







I can tell you that when I do drive it on the street, it is... somewhat fun!

[bigchillcar]

wow...hate to ask a dumb question, but i've never seen anything like that part from smartracing. is it for more than rigidity?
ryan

[Mahler9th]

Here is what it looks like:

[Bill Verburg]

Assuming that the rear tires are ~25.6" tall
here's what you trans looks like

[strosekmega]

Your crazy...... this will be the second comming of christ!

PRAISE THE PORSCHE GODS!!!!

You rock, keep up the awesome work!!!!

[mjshira]

this is becoming one of my all time favorite threads, nice work! Now my parts bill doesn't seem so bad... ;-)

[911teo]

Elf, Edward, James... thanks for the thumbs up!

Mike...
there will always be a way to do something better and cheaper... that's the challenge that we all take upon us. Your carlooks fantastic and by the sound of it it's a phenomenal 911!

Bill
thanks for running the transmission on your program! Awesome... After all I was not too far away in my1st hestimate!

Bigchill
The transverse tubing is nothing to do with the Smart Racing towers... It's a tool Zuffehaus will use to weld the towes in... I think!

[Mahler9th]

Well... make sure you have an ample budget for rear tires!

By the way, the builder of my car has basically the same thing (about 1950 pounds) with a 3.8 tt motor making about 700-750 bhp at 1 bar or so....

It too has a license plate and he drives it to and from work from time to time... I am sure that's fun!

[jpahemi]

Matteo:
I caught this thread late, looking at the jugs, the inner wall seems unusually thin; is this the max diameter you can go with the 993 case?
j.p.