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Tue Oct 24, 2006 7:35 am

gears wrote: Proper gearing range for VW.

Do you have the stock 1st-4th ratio's for a 930 tranny? Since I'm not going to be anywhere near a stock VW I wantt o make sure I get my gearing where I want to see it. In 4th the car needs to be able to hit 140mph around 6800-7000rpms and be in the 2500-2800rpm range at 80mph. This will be a driver than needs to be able to have some top speed and have good RPMS at freeway cruising speeds. The turbo's will pull the car through the gears. So I would perfer them to be long pulls. I was thinking a 3.88 R&P

Tue Oct 24, 2006 8:06 am

No disrespect intended, but a '61 bug with Turbo(s), street-driven, occassional drag racing, must do 140 mph? A bug is set up to be one or the other .... drag car with slicks, ALL the safety gear (w/ parachute), or it's a street car.... that won't likely be doing any 140 mph. A combination of the two is a fantasy bug, at least in my book.

Tue Oct 24, 2006 12:27 pm

gears wrote: No disrespect intended, but a '61 bug with Turbo(s), street-driven, occassional drag racing, must do 140 mph? A bug is set up to be one or the other .... drag car with slicks, ALL the safety gear (w/ parachute), or it's a street car.... that won't likely be doing any 140 mph. A combination of the two is a fantasy bug, at least in my book.

None taken. Yes, it must have a gearing that will allow 140mph. 5 years ago people would say a 2332cc was not streetable, same with 94mm pistons. Someone has to pioneer it. I feel it can be done and will do it. Do you have the stock gearing info for the 930? People told me my 1000whp twin turbo mustang could not be streetable.. It got 28mpg and was driven 200-250 miles a week.

Tue Oct 24, 2006 12:45 pm

2.250 (16:36)
1.304 (23:30)
.893 (28:25)
.625 (32:20)

4.222 (9:38)

4.875 (8:39) alternate R&P

Good luck on your project.

Fri Oct 27, 2006 6:08 am

I have been looking for several days and can't find a 930 transmission that isn't expensive. So far the cheapest I have found was $2600 for one.
I'm now at the point of needing the tranny.
Can I use a 901 or 915 trans and build that so it wil hold 400-450HP? If so, who makes the parts and what is needed exactly?

Fri Oct 27, 2006 8:00 am

no, why do you think Porsche built the 930 tranny?

901/915 trannys with that hp will shear the pinions.

Fri Oct 27, 2006 11:00 am

We used to drag race a 440 hp VW (9.30's quarter-mile) with a built Type I trans. https://www.thesamba.com/vw/gallery/pix/296774.jpg

The cost of duplicating that 4-speed trans today would be $3,000+. I would give a properly built trans like that a much higher rating than the 915. Consider also that the VW synchros are way superior to Porsche-patented synchros in 901, 915, or 930.

The 930 trans would be WAY stronger than any built-up VW trans, but you still have the issue of gearing that is too tall without changing out the R&P or gears. The least expensive 930 core you're going to find anywhere is $1,500-1,800 .... for a trans that needs some level of rebuilding.

If the perfect trans was out there (strong, cheap, properly geared), everyone would be using it and everyone would know about it.

Fri Oct 27, 2006 12:15 pm

I'll buckle down and open the pocket book then.
When I get it I'm going to tear into it to make sure there's no problems.

Sun Oct 29, 2006 7:41 pm

A 930 is 300 HP and will pretty much do 100 in third gear. It'll out last a 300 HP type 1 engine for sure.

Sun Nov 12, 2006 4:55 am

Is there a way to build the 901 transmission so that is will hold more than 300HP? What makes the 901 weak? Those parts that are weak, is there an aftermarket part that is stronger or a part from another tranny that can be crossed over that is stronger?

Sun Nov 12, 2006 8:25 am

Redesign costs are considerable, with little guarantee of recouping an investment. For starters, the shaft-to-shaft distance is too small, and increasing this would yield ...... a 915.

Sun Nov 12, 2006 1:31 pm

Can I use a 915 shafts to fix this problem? WHatever tranny I buy I will be going through it before it goes in the beetle.

Sun Nov 12, 2006 3:35 pm

gears wrote: ...the shaft-to-shaft distance is too small, and increasing this would yield ...... a 915. No, you can't use 915 shafts in a 901 to cure the issues with the 901. Nor is it economically feasible to redesign the 901 to be "as strong as" a well-built 915. sooo... the answer is to use a 915 in your Turbo project and replace it when it fails (if you need 5 speeds).

Mon Nov 13, 2006 6:53 am

Gears and everyone else I want to thank you for all your help.
I found a 1973 and 1973.5 915 trans. Neither has an LSD.
Is there any difference between these 2?

Mon Nov 13, 2006 8:20 am

The later the better for 915s pressed into Turbo service. Those '73s should both have the sought-after 7:31 R&P (which isn't necessarily what you're after), and the somewhat problematic early 915 mainshaft. '76 & later have the 8:31 R&P ('75 is an "odd" year), somewhere around '78 entered the later mainshaft, and the '85-'86 will have the strongest side cover.

Mon Nov 13, 2006 8:29 am

gears wrote: The later the better for 915s pressed into Turbo service. Those '73s should both have the sought-after 7:31 R&P (which isn't necessarily what you're after), and the somewhat problematic early 915 mainshaft. '76 & later have the 8:31 R&P ('75 is an "odd" year), somewhere around '78 entered the later mainshaft, and the '85-'86 will have the strongest side cover.

Can the main shafts from the 73 be replaced with the newer style without problems?

Mon Nov 13, 2006 1:38 pm

Yes, it's a straight bolt-in replacement.

Wed Nov 15, 2006 7:16 pm

What years did the 930 tail shafts come out? Im looking for one for a 74 german look im doing. I was going to use and have a 914 but im also having a pretty big type 4 turbo set up.

Thanks in advance.

Wed Feb 14, 2007 8:54 pm

Its been awhile since I have been one. I bought a 915 trans out of a 76 back in Dec. Well never got it. Just lost money. So I'm back in the market for another one.

I have been looking again and came across some 915's However the weight and numbers on them are different. One weights 88lbs and the other 138lbs. How is this possible and what should I look for?

Thu Feb 15, 2007 7:46 am

Sounds like you'll lose money again on the 88 pound one ...