Why such a slow ratio on first. I have been lining up parts for my tranny but I was going to likely go with below. With the power you are pushing and your perfered use of the car I figured my ratios would be more suitable for you. Just my thoughts and what are yours? I do not find the gap between 1st and 2nd to large I just find 1st way to low. I mean wayyyyyyyyyyyyyyyyyy!

1st 2.69 or maybe 2.883
2nd 1.89
3rd 1.364 or 1.333
4th 1.12

 

Hi,I think the gap on our stock trans1 to 2 are to wide...
Here is why>>If you look at the spread of the RPM drop, it pulls the RPMs down to much into the TQ range then in the higher HP accelerating range on the 1 to 2 shift..By about 500 rpms..Which is almost the same as the Harley trans...When we install a closer ratio and longer 1st with the High HP motors I have built,,its a better launch and keeps it in the higher RPM range so it doesnt take time to get up there again like from the wide spread ratio drop to lower RPMS..
Usually that gear change is worth .2 tenths and more consistent..
Just sharing my info and thoughts here..
Also a 2.69 gear or a 2.883 is lower/longer then the 3.15 ratio which those would be real tall in my opinion plus it has to be mated to the right 2nd gear to work,,just my opinion..

 

John the main shaft has 1st & 2nd drive gears cut on it, so 1st & 2nd are set. 3-6 can be made what ever you want. You can go with Guards parts and make anything you want.

 

Thanks Tim,,,What do you think in your opinion that close ratio gear swap would cost?

 

I know what you are saying but the weight of the car and the poor launching platform the high first gear is really hard to drive. 3.15 seems to work very well. I used it in the passed and will be doing the same build but with the whole set 1-6.

 

I would have thought that with the power some of these guys and you are making the slow first would be prohibitive because you would be tagging the rev limitor in 1st so quick and spinning so hard that you would want something a little taller; also your even bigger spread between 1st and 2nd then the ratios I stated would make for more of an RPM drop and would be less friendly to your bigger turbos in terms of lag inducing RPM drop. Your ratio choices between 1st and second is almost the same spread as the factory gears but a tad bit higher speed at redline.

Hmmm maybe I will play it a little safer and go with my 2.88 choice for 1st. My car is for road and track use so I am not worried about launches.

How come he's not going with Guards tougher Billet main shaft and more modern tooth profiles, is it just the cost? Yeah going the Guard route does add some expence but I am sure it would pay off in the long run for you High HP guys as the components are a whole bunch tougher, especially if you can live with a few straight cuts in 2nd and 3rd.

 

I am confused with your wording?...Do you mean to say short instead of slow because I think that would fit better?I think you do?
We all my bike builds and old muscle cars when I put more power on them I make the gearing taller for those reasons also..
Shorter would mean the other way in the gearing like what we have now,,too short/fast of a first gear..
Just trying to understand and share with you..

 

Short = slow.... 3.15 is a slower ratio speed wise then a 2.88
Tall = Faster.... 2.88 goes faster at redline then 3.15

First gear in a 911 TT is way to slow or short a gear, it needs to be taller, or a faster first gear.

The spread between 1st and 2nd is to wide or tall on a stock 911TT, I want a slightly shorter or closer ratio between the two gears.

 

I learned some new wording now..
I always used and understood short / tall with my circle..
Thanks.

 

Hmmmmmm interesting !!

I will say 3rd gear is a "HELLO" as k tim what I told him.

Btw no split Mainshaft??

 

timmy and i are working on it. we woulda had it running last weekend but we didnt have a case and retaining plate. so no we r on a search

908whp and 850wtq

nope the first part number i put up includes the new nicer mainshaft that already has 1st and 2nd on it. 3rd is seprate set.

The way i look at it 3.15 is going to be wayyyyyy better then stock 3.8x , plus I like the fact that they are OEM 997 GT2 gears with wider and stronger 3rd gear. With my 27.2" drag tire 3.15 first gear will take me to almost 60mph which is quiet nice

Suncoast got me the parts in less tehn a week ...

 

im not sure i have heard slow/fast before but as far as i know here is the correct way.

the higher the ratio the shorter the gear. example 3.83 is shorter then 3.15.

a taller/longer gear will let let you get to a higher speed in that same gear. same way a taller tire would give you more speed in any gear.

 

sucks to hear about the trans..

Get that ***** up and running for Etown Dec 1st... i got alot of fast cars signed up

 

my car cant compete with those killers

 

we got a few GTRs coming in your power range

we got stock all the way to one that just made 1320wheel and not even done tuning

there are a few in the 700-1000wheel range coming