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Hi guys, my 2004 GT3 CS box gave up last night, third gear blown. Going to do a overhaul and rebuild.
As the car gets significant track use, 25 plus events per year.....And she is a long-term keeper, keen to know what makes sense re-upgrades? Better synchro rings? Other?Noted people recommend the LSD by Guard.
Funds are limited so it’s about what makes most sense re bang for your buck’s etc.thank you.
oh man, my condolences. My understanding is that when third blows it causes significant collateral damage such that a lot of internal stuff then needs to be replaced. You might actually be better off sourcing a used gearbox at that point. I just went through this and my gearbox was not even that bad and all gears were intact, and it still cost over 15k. There will also be a lot of “while you are in there” kind of stuff to do. Likely going to need a new pump as well because Lots of metal probably went through it and chewed it all up. On the bright side, you clearly got your money’s worth out of it from other threads you posted! “While you are in there” is now a great time to lower the gearing a bit either with shorter gears or a shorter ring and pinion. I did the 3.89 ring and pinion a d it absolutely improves acceleration and “fun factor” for me. Good luck!
Definitely do the cup car synchro if you are doing that much track work. Some guys on here sing praises about re-gearing the transmission ($$$&) or you can just do cup car 4:1 final drive which is a lot more cost effective. I had final drive in mine and love it. Drive off corners was fantastic despite compromise with gear ratios.
i've had mine rebuilt and it gets expensive and takes a while as some of the parts needed to be shipped from Germany, so much so i bought a spare box in the end. The bearings are $300+ a pop and there are alot of them, if you need a gear replaced that's $1500+ for each gear. Depending on how much needs replacing you could be looking at between $8k-16k. if car is track used 3rd and 4th gears will likely be the wear items along with syncros, bearings and the final drive. The best change i made was the 8:32 (4.0) Ring Pinion ($4k) as the acceleration difference is very noticeable. I agree with the feedback on syncros, i believe steel are the better ones
Many options here and many threads discussing it. There are a couple different R&P options or keep the stock R&P and change gears 3-6 or 3-5. Or do both.
I went with keeping the stock R&P and regearing 3-6 with 997 Cup gears and synchros which really makes the ratio closer between 2-3-4. The biggest benefit is going from 2-3 is much closer ratio which really helped my corner exit power in certain higher speed corners especially if uphill exits.
Bill Rader regraded my 3-6 and Guard internals in the factory LSD. Plus he put the heavy duty side plate on. Very happy with his work. He is located in Las Vegas at Rader Motorsports.
Call brian copan, he will set you on the right path! Its worth every penny!
+1^
He rebuilt my turbo box w/GT2 main1/2/3, all steel synchros and Cup LSD, ported for a cooler and still running strong on and off the track 20k miles later.
06-04-2020, 11:53 PM
Gearbox Re-build - Upgrades
