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vennard
December 26th 2003, 18:51
I know most people on here are either doing or dreaming of 5 speeed boxes. BUt what I am going to have to do for the mean time at least is strengthen up a 4 speed and put up with it.
With this in mind I am slowly building a 1914 turbo that is mostly for the weekend and a bit of strip use.What should i do to strengthen a four speed from a 72 bug to handle this kind of power. Please explain in simple terms as I have had no experience with the inside of gearboxs to date.

Cheers

Karl
CLKWRK
December 27th 2003, 00:28
Hi,
In simple terms,
spend $$$ on your type 1 box, or use a bus transmission.
Bry:D
vennard
December 27th 2003, 09:03
Yeah. had that sussed out already. But where to spend them and what is involved in fitting a bus box.

Cheer karl
ydeardorff
February 29th 2004, 00:47
If your interested I have a porsche 912 4 speed I'll sell. All I ask is the core value for it. It is in good working order as far as I can tell.
Bruce2
March 1st 2004, 03:45
I've never understood why anyone would do all that fab work to install a P 4speed. What's the point? You still only have 4 gears.

Karl, assuming your car is IRS, get yourself a single side cover IRS trans from a mid 73 or later car. Then simply install a super diff. The super diff works exactly the same as a stock diff, but instead of relying on 2 spider gears to transmit the power, there's 2 extra spiders in there.
The next upgrade would be to change 3rd and 4th gears for the coarse tooth early types, and have the syncro hubs welded on. To convert the gears to work in your trans requires modifying the gears on a lathe. The 3-4 shift hub also needs modifying. Once you do those two upgrades, there's pretty much nothing that can be broken in the SSC trans.
vennard
March 4th 2004, 18:23
Ydeardoff. Thanks for the offer but im over the other side of the pond in the sunny uk. Time I get it over here ill be way out of pocket. Thanks again though.

Bruce 2, Thanks for the info but its all swing axle over here. Was gonna convert but hoping to save a bit of cash staying witha strong swing axle 4 speed. Do you know how I can strengthen a s/a trans on a budget???

Thanks for the help

Karl
Chris Percival
March 5th 2004, 07:05
Karl, speak to the Cogbox, they will be able to give you advice and will be able to supply the parts too if you wanted to do the work yourself..
vennard
March 6th 2004, 14:32
Chris, Yeah been meaning to give them a call, I just wondered if there was a way of doing a temporary 'fix' to make it strong enough to get me through the summer. £££ a bit tight at the moment :rolleyes: dont think I can stretch to a superdiff right now and dont want to spend thousands on the 4 speed 'cos at some point Im gonna change for a 5. Maybe Ill just run it as standard and try to take it easy :D
Chris Percival
March 7th 2004, 15:36
Chris, Yeah been meaning to give them a call, I just wondered if there was a way of doing a temporary 'fix' to make it strong enough to get me through the summer. £££ a bit tight at the moment :rolleyes: dont think I can stretch to a superdiff right now and dont want to spend thousands on the 4 speed 'cos at some point Im gonna change for a 5. Maybe Ill just run it as standard and try to take it easy :D

Yeah, I know people that have run standard boxes for ages. Its off the line that breaks them, just pre-load the box and take it easy on launching, then get into second and third and let the turbo spool up and do its work...