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Sandeep
February 20th 2003, 16:57
Hiya,

I'm going to run a 914 2.0 (95hp) with BAS header, 44 IDF's and Porsche cooling this spring and its all hooked up to a STOCK '72 4 speed trans in my '74 beetle.

I'll be daily driving it through the summer and will be hitting some drivers ed's and autocrosses.

Questions:

How long will this trans last ?

Can I do some drag race starts ?

How about full throttle application after shifting ?

I'm a newbie to trans questions and will upgrade in the future, but will I kill this trans in one summer ?

Thanks for any input !

Sandeep

Michael Ghia
February 20th 2003, 18:24
Sandeep,
It's a kinda "how long is a piece of string" question.
I have seen stock Bug gearboxes used in drag racing rails (seriously!) last indefinatley and I've seen £3000 gearboxes blow on the first take off...
It just depends on how you treat it.
If you're running street tyres, you've less chance of breaking it than if you run slicks,
If you setup the rear suspension for drag starts (i.e. quite soft for good weight transfer) then the trans will last longer than if you set if up hard as it will take the shock out of the take off.
There are so many different things to look at.
As for power shifting, the same thing applies, if you slam your foot off the clutch having buried the accel pedal before hand, you're more likely to slip the clutch or shock the transmisison and break something than if you wait to get the clutch up fully and then nail it.
If you're nice to it, it should last! and last.

Rich Olafsson ran a stock 1300 box for 6 months with 240bhp from an Impreza Turbo lump but as you can't control the sudden turbo boost, it died evetually. He's pretty nice to it.

MG

Martice
February 20th 2003, 19:27
How about "welded" 2nd and 3rd gear? what is the precise purpose of this operation and what exactlly is the operation?


Martin

Sandeep
February 21st 2003, 10:03
Thanks for the information Mike.

Looks like I will start making plans for a beefed up tranny .. so many options now ..

Sandeep

kdanie
February 21st 2003, 12:34
Martin,
Early transmissions had the drive part of the gear pressed on, newer trans they were already welded from the factory. If I remember correctly only 3rd and 4th need welded. I have some pictures at home I can email you that show the operation. I will try and include the text from the book also.
ken

Martice
February 21st 2003, 13:32
Thanks Ken!

here is my email: martinchirita@yahoo.com

Wanzer74
March 8th 2003, 19:05
sandeep, i have been running a stock sb trany and have had no probs what so ever. i do have steet tires on but i did run into a worn out flywheel from a bad starter,chiped the hell out of it. the down fall i do have is on the top end, everyone is in my dust till im runnin at 5 grand and out of forth. thats when i get passed up.(and i have gone way faster than 95, its the darn wind tossing me all around that keeps me from top speed.