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Shorter Gears & Rev Matching?

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Old 12-24-2018, 08:54 PM
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mcomet
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Like others have said apparently no issues with rev matching. 2nd gear is supposed to be out sometime 2019 from what I have heard. Still it will be pricier than 3-5 or 3-6... I'm still mulling... I have some remodeling I want to do plus a wrap on the car... or maybe I will say screw it and do it all... LOL. Your best first step is headers... if you don't care about sound. Even sport headers are louder tho... I've yet to go back to Laguna Seca with mine... I was doing the lift and upshift by the sound station...that -should- still work even with headers...
Old 12-24-2018, 10:33 PM
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Five12Free
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Originally Posted by mcomet
Like others have said apparently no issues with rev matching. 2nd gear is supposed to be out sometime 2019 from what I have heard. Still it will be pricier than 3-5 or 3-6... I'm still mulling... I have some remodeling I want to do plus a wrap on the car... or maybe I will say screw it and do it all... LOL. Your best first step is headers... if you don't care about sound. Even sport headers are louder tho... I've yet to go back to Laguna Seca with mine... I was doing the lift and upshift by the sound station...that -should- still work even with headers...
I think he’s past that... he has a 4.0L engine
Old 12-25-2018, 07:53 PM
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GoKart Mozart
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Originally Posted by mcomet
Like others have said apparently no issues with rev matching. 2nd gear is supposed to be out sometime 2019 from what I have heard. Still it will be pricier than 3-5 or 3-6... I'm still mulling... I have some remodeling I want to do plus a wrap on the car... or maybe I will say screw it and do it all... LOL. Your best first step is headers... if you don't care about sound. Even sport headers are louder tho... I've yet to go back to Laguna Seca with mine... I was doing the lift and upshift by the sound station...that -should- still work even with headers...
For me I would want a shorter 2nd gear (and first if it's available), or this mod isn't worth it (to me). Maybe purley for the track the 3-5 makes sense, but for the street and speedlimits we deal with, 2nd gear is the most used gear and where the car would benefit the most from more "power".

What headers do you have? The Fabspeeds? I would love to do headers, but want to retain cats and not be too loud, for the same reason you mentioned ......Laguna Seca.
BTW, are you suggesting even stock the GT4 is too loud for LS? What about turn down pipes?
Old 12-26-2018, 12:03 AM
  #19  
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Yes for street 2nd would be amazing. I have Soul Performance 200 cel street cats. Definitely louder but not as crazy as catless race header. Search here you can see threads and review and videos I posted.

And yeah stock gt4 won’t pass Laguna Seca either. At least not a 92db day. Unless you get turn down pipes. Even with valves set to close I basically was instructed to up shift half throttle and move left every time I passed sound booth. My instructor who also had a stock GT4 forgot one lap and was black flagged for that session...

Last edited by mcomet; 12-26-2018 at 10:41 AM.
Old 12-28-2018, 11:33 AM
  #20  
GTgears
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Originally Posted by GoKart Mozart
For me I would want a shorter 2nd gear (and first if it's available), or this mod isn't worth it (to me). Maybe purley for the track the 3-5 makes sense, but for the street and speedlimits we deal with, 2nd gear is the most used gear and where the car would benefit the most from more "power".
We will only be offering a different 1st gear ratio by special order. The reason for this is that reverse is integral to 1st gear and if you change the ratio you need a new reverse as well. That will increase the price of the mainshaft kit by about $500. On something that is already so expensive and a change that is of arguable value it would be shooting ourselves in the foot to do it.

We will release the mainshafts sometime in Q1. You can thank President Cheeto and his trade war for the delay. The disruption in the steel market has been pretty big with the suppliers we use.
Old 12-28-2018, 11:43 AM
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Originally Posted by cooperlee
I went with shorter final drive from Autoquest with lightened flywheel and new sachs clutch. Car is dramatically transformed with much quicker acceleration. Feels like an additional 50hp is unleashed. Only small issue is lower top speed which I don't need

https://www.autoquestcars.com/custom-10
Have you posted any driving videos of your new setup?

Last edited by UFreefer; 12-28-2018 at 12:01 PM.
Old 12-28-2018, 12:40 PM
  #22  
GoKart Mozart
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Originally Posted by GTgears
We will only be offering a different 1st gear ratio by special order. The reason for this is that reverse is integral to 1st gear and if you change the ratio you need a new reverse as well. That will increase the price of the mainshaft kit by about $500. On something that is already so expensive and a change that is of arguable value it would be shooting ourselves in the foot to do it.

We will release the mainshafts sometime in Q1. You can thank President Cheeto and his trade war for the delay. The disruption in the steel market has been pretty big with the suppliers we use.
OK, that might not be worth it then, but how does the 1-2 upshift feel then with only the 2nd gear being lower? Conventionl wisdom would suggest that all gears need changing, meaning the final drive ratio being a better way to go.
I got to say, I fin myself driving in 4th and 5th lots of time on short hwy sections, and only when I really cruise I use 6th, but then find 6th almos to short, which is weird. My ideal fix would be to lower overall ratio and make 6th longer, but that would not be a deal breaker.
Old 12-28-2018, 02:34 PM
  #23  
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Originally Posted by GoKart Mozart
OK, that might not be worth it then, but how does the 1-2 upshift feel then with only the 2nd gear being lower? Conventionl wisdom would suggest that all gears need changing, meaning the final drive ratio being a better way to go.
I don't know what your conventional wisdom is. Stock RPM drops on the 1-2 shift is a tick over 3000rpm. Our 2nd gear ratio takes that down to around 2400rpm with you entering 2nd right around 5000rpm. The combination of 1st and stock final drive has top speed in first near identical to a 997 Cup Car. I'm not sure why you would want it any shorter. But to each their own.
Old 12-28-2018, 04:29 PM
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ajw45
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Originally Posted by GTgears
We will only be offering a different 1st gear ratio by special order. The reason for this is that reverse is integral to 1st gear and if you change the ratio you need a new reverse as well. That will increase the price of the mainshaft kit by about $500. On something that is already so expensive and a change that is of arguable value it would be shooting ourselves in the foot to do it.

We will release the mainshafts sometime in Q1. You can thank President Cheeto and his trade war for the delay. The disruption in the steel market has been pretty big with the suppliers we use.
Originally Posted by GTgears
I don't know what your conventional wisdom is. Stock RPM drops on the 1-2 shift is a tick over 3000rpm. Our 2nd gear ratio takes that down to around 2400rpm with you entering 2nd right around 5000rpm. The combination of 1st and stock final drive has top speed in first near identical to a 997 Cup Car. I'm not sure why you would want it any shorter. But to each their own.
Thanks for the update! I didn't realize the mainshaft kit had gotten held up and have been asking the shop for a quote since Thanksgiving. Oops. I guess I should stop bugging them for a few months and drop off a bottle of scotch instead. Can't believe how far the Trump effect spreads <sigh>

This sounds perfect, can't wait for the official release! I don't mind the long first gear, it makes first very usable and then you can really tighten up the spacing from 2-4. I really just want to get 2-4 shorter/tighter for less of an rpm drop between gears and lower speeds in gear so the ratios are more usable on the street. I understand there might be little to no track performance gains but it would be nice to have a snappier feel in gear. How much shorter is the new 2nd gear? With my redline bumped to 8k+ 2nd and 3rd are just stupid loooooooong.......
Old 12-28-2018, 04:51 PM
  #25  
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2nd gear will be 2.25 versus the stock 1.95. We will still offer several ratios for all the upper gear positions. For track people it will make a difference in the higher gears.
Old 12-29-2018, 11:18 AM
  #26  
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Originally Posted by cooperlee
I went with shorter final drive from Autoquest with lightened flywheel and new sachs clutch. Car is dramatically transformed with much quicker acceleration. Feels like an additional 50hp is unleashed. Only small issue is lower top speed which I don't need

https://www.autoquestcars.com/custom-10
I don't see how changing final drive would affect rev-matching, as all the gears are the same relative to each other. Someone please set me straight if I am wrong.
Old 12-29-2018, 11:53 AM
  #27  
GoKart Mozart
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Originally Posted by GTgears
I don't know what your conventional wisdom is. Stock RPM drops on the 1-2 shift is a tick over 3000rpm. Our 2nd gear ratio takes that down to around 2400rpm with you entering 2nd right around 5000rpm. The combination of 1st and stock final drive has top speed in first near identical to a 997 Cup Car. I'm not sure why you would want it any shorter. But to each their own.
I meant that conventional wisdom would suggest that Porsche got the spacing between the gears right, but just made them all pretty long. What you suggest sounds good though. It sounds like an improvement and that it won't be worth messing with 1st (which is what I meant) Thanks!



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