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How much time is there in a Tranny ?
55slug - September 15th, 2006 at 11:31 AM

Last Summer I was running 13.9@95 ish mph with a 3.88 r and p and stock gears (3 gear 1/4) with a 205/60 tyre.

This season Im running a 4.37 r and p and 3.78,2.35,1.58,1.21,.82 gears with a 205/70 tire.

Im hoping to hit mid to low 13s on radials ?? Just wondering wether my guestimate is ballparkish for times ?


Gracey - September 15th, 2006 at 12:35 PM

I've been told about half a second for close ratio gears, but I'm not really sure.

What type of 5 speed box are you using?

Andrew


dangerous - September 15th, 2006 at 02:38 PM

It depends on the engines power curve, but a couple of tenths would be minimum.
Un fortunately the 4.375 diff ratio will cause you more wheel spin than 3.875,
so perhaps a taller tyre might be in order.
Rod Richardson recently ran in the 12s on 205x70 tyres.

I am a real fan of tall first gear ratios,
because the most ET to be gained is in the first 60 feet,
so less wheel spin here can only help.


55slug - September 15th, 2006 at 02:49 PM

As it was I was spinning the whole way through first, I have been thinking about the M and H DOT legal slicks (215/65/15) but I dont really want to start breaking other stuff. I ran a best 60ft of 1.9 from memory.

Heads for the engine were ported with torque in mind with the ratios I had and the car being full weight (55 on a 77 pan) with an IRS rear. If I plant it round any corner it lights up pretty well. Pulls from go till 6500ish.
Thats why I am building the 2332 fk87 wedgie combo.

[ Edited on 15-9-2006 by 55slug ]