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Posted by: PanelBilly Jan 24 2014, 07:15 PM

Seems like its money we'll spent to change the gears and take full advantage to all the power a bigger engine produces, but what did you do? And if you didn't, do you regret it or are you happy starting in second?

Posted by: PanelBilly Jan 24 2014, 07:15 PM

I think I screwed up the poll questions!

Posted by: mepstein Jan 24 2014, 07:42 PM

For my 3.2 conversion I had Doc Evil pull the first gear and add an H gear for 5th. I have a spare box if things go wrong or I want to experiment with other combos. I have not driven the car yet.

Posted by: Trekkor Jan 24 2014, 07:53 PM

C or D first gear. Totally worth it!

I run the C first. It's good to 45mph at 7k and you can downshift into it at will.

I run the stock F 2nd, flipped ZD 3rd ( Ka )
S 4th and X 5th.

I would only change 5th to a stock ZD if it were a street car.

Posted by: SLITS Jan 24 2014, 11:01 PM

I run a stock 914/4 box and am happy with it. Even my 911 buddies are changing their gear boxes to a /4 5th ....

Posted by: r_towle Jan 25 2014, 09:45 AM

Depends upon what type of driving you intend to do.
Street, autox, track?

Money well spent, yes.
But I suggest you drive it stock first, then choose.
Get a core, spend the time after you are driving it to clean up a second transmission and build it as you find will work for the type of driving you are doing.

Posted by: Eric_Shea Jan 25 2014, 10:20 AM

Agree with Rich. You can support the motor and yank the tranny fairly easily but, if you know your intended use you should be able to put something together that works for your style and your engine.

I'm not in favor of a taller first for one reason, the shaft isn't really strong enough for that type of driving with that type of torque. I've had mine spin the shaft right there. Life is not fun with first rattling around in your tranny nose cone.

I would concentrate on 2nd-4th to take advantage of your power and torque band and plan 5th for best mileage and economy. The only problem with having a tall 5th in an air cooled motor is, they can depend on the RPMs and the fan to keep them cool. This is why the 914-6 received a Za gear for 5th. If you have a front cooler, which I think you do, you can worry less about that. I'm not sure what a Carrera gear set would be but, there's a car of similar power that has a front cooler and, in stock form, would potentially deliver the best cruising fuel economy in 5th. You're also lighter so you may be able to go slightly taller and get away with it.

Here's how the theory played out in my tranny. I'm a 2.5 SS so it will be quite a bit different. I went with a stock first and second then, M, S and instead of the familiar "X" I used the stock 6's Za. I wanted a gear tall enough for cruising but short enough to play well with the S if I had to downshift on a long grade.

You have torque and tons of it. If I recall from building your suspension, you want a street driver that you can have fun in the twisties with.

Posted by: Dr Evil Jan 25 2014, 12:16 PM

A bigger 1st is costly and unnecessary for street. My favorite setup that gets good reviews is A, F, O, X, flipped H with elimination of A depending on the engine. I also agree that stock /4 gears are pretty dang great and inexpensive.

Posted by: Trekkor Jan 25 2014, 12:27 PM

I found my C gear set for $100 at a Porsche shop.

Posted by: brant Jan 25 2014, 12:31 PM

cool..
I'll give you $110 then and even pay shipping and paypal fee's

Posted by: Dr Evil Jan 25 2014, 03:08 PM

Ya, Trekkor always likes to brag about his $100 C gear. Its not a fair comparison to tell people as the chance they will find one is slim. Last I checked they were $700-1000.

Posted by: Mark Henry Jan 25 2014, 07:05 PM

I have both, sort of... one is a stock 914/4 and the other is a A, F, O, X, HB

I know Doc..... not as good as an H...

Posted by: Dr Evil Jan 25 2014, 07:20 PM

Nah man, HB is only a tooth different. Good gear I have one for sale for a rebuild

Posted by: brant Jan 25 2014, 07:23 PM

F/J/O/S/V
redline 7500... up to 7800 or more if you're brave

but the stock 4 cylinder box wouldn't bother me on the street
I feel like you could use 1st gear if pulling away normally
maybe not for burn outs, full throttle torque, but normal use

Posted by: PanelBilly Jan 26 2014, 12:27 AM

So where is HB on the chart?

Posted by: Mark Henry Jan 26 2014, 12:48 AM

HB is a oddball 4 speed gear between H and HA. It's not on some charts. HA is a 5 speed 2nd and can't be used.
H, and HB are 4 speed 2nd gears that are flipped making a 5th.
Flipped H is a sought after gear for the V8 crowd.

This chart shows the gears and what boxes they are in, of course many boxes now have who knows what in them.

Posted by: wndsrfr Jan 26 2014, 07:56 AM

First consider what tires you're going to use on the track. I'm very happy with the stock gearing on my 2.7/6 using 225 45 15 tires which are about 5 percent smaller diameter than stock. this give the benefit of a re-gearing for the track and lowers the car about three quarters of an inch. On the street I'm using 225x50x15 and don't abuse first gear at all.