rbahr

Hi All,

My Tranny is out of the car and apart - what are recommendations for a track car?

Does anyone have experience with Gbox and their dog ring replacements?

I will update the LSD with new (perhaps Guard) plates, probably any syncros that look a little worn with the Cup parts... I may also add the Cup car filter..

Thoughts?

Thanks

Ray

kk2

consult guard for everything. One of the guys is a member here. GTgears or something.

996FLT6

Pm Matt aka RL name "Gtgears" of Guard. Stellar guy and a wealth of information with respect to tranny and lsd's. When u say cup car filter are u referring to what 6cup cars have? If so won't work with our cars as it has no provision for the MAF sensor and since cupcar filter is dead on center in engine bay there's no center vent on stock decklid. Got pics of your car? Enjoy when it's all fixed up- great cars!!! Mike

rbahr

Hi 996flt6,

The 996 Cup cars have a transmission oil filter...

Ray

GTgears

Here is why you don't replace the dog rings on 2nd gear on a GT3:


The welding on of the new ring compromises the heat treat of the gear and kills the temper. This gear ripped apart exactly where the new welds were located. This gear was done by the shop you asked about.

And if you use that shop for your gearbox service, you will not be rebuilding with our internals. They are not a Guard authorized installer and I won't even sell you the parts directly to take to them for installation.

rbahr

Hi Matt,

Fear not, they are not doing the work on the tranny, and for cost of the OEM main shaft, 1st & 2nd gears (IMNSHO) it would not make sense to try anything like this...

Sorry for any misunderstanding - I am just in the information gathering phase of my little adventure.

Ray

GTgears

Ray,
No worries, no misunderstanding. I'm just educating the public around the suggested repair and why to avoid it. And you don't know how many times I get the call,"Hi, by gearbox is at so-and-so getting rebuilt and I would like you to drop ship some of your clutches to them". If I publicly state that is not an option, I get fewer of those requests.

Regards,

Matt

cfjan

Matt,

A quick question for you. When people replacing gear sets (either for refresh or re-gear purpose), do you tell people to drop in straight cut gears? (if people don't mind the extra noise) Straight cut gears are stronger, right? Are they also more expensive? (I am guessing straight cut gear is cheaper to make?) The drawback is the noise, of course..

More for a curiosity...

GTgears

Sorry for such a long lag between replies. We've been moving both our house, and the business (consolidating them into a single location) and I've been burning the candle at both ends. Yesterday was my first actual day off in about a month.

Anyway, to answer your question, I don't really advise one way or the other strictly speaking. For years you couldn't get Porsche guys to buy straight cut synchro gears. Porsche Motorsports themselves published some rubbish about why helical gears were better and since so many Porsche owners take the "oem is best" line of thinking the general public bought it. This goes back to the 996 Cup, all of which used helical synchro gears in them, as did every air cooled Cup Car Porsche ever made.

We started making straight cut gears for the G50/G96 line of gearboxes over 10 years ago. Given the environment, very few people outside of pro motorsports would touch them. Reiser-Callas, Alex Job, TRG, and others were using our gears in their cars but Club racers and DE guys wouldn't touch them.

Fast forward to today where Porsche Motorsports now runs the Holinger sequential gearbox (actually an evolution of our Pro-Shift line which we co-developed with Holinger). Porsche has reversed their official position on straight cut versus helical. So now suddenly, I can sell helical gears to GT3 owners because the mothership does it on their racecars. Funny sort of herd mentality there really.

Making a straight cut gear costs no more or no less than cutting a helical gear. They both go on the same machine. They get programmed differently, but they both start with the same billet ingot and take the same amount of time to cut. What many people don't realize is that the quality of a gear does have a direct relationship to the feed rate on the gear hob. We feed our gears very slowly.

A straight cut gear is stronger. It is also noisier. For a GT3, it's really a non-issue. GT3s don't make enough power that the difference in strength, which is maybe 10-15%, is going to make or break a gear. When we do 1000whp GT2s and 996TTs it comes into play. But for a GT3 track car, it's a personal choice really, which is why I never push them on people, though I generally have them available in the more popular 3rd and 4th gear ratios.

Regards,

Matt

powdrhound

Both Gbox and Guard are local to me. When I was looking to upgrade my LSD I visited both Gbox and Guard to talk to them in person about my options. When I visited Gbox I spoke with the owner (Stan) who did nothing but bad mouth Guards products claiming they would perform horribly and how his LSD (Gikken) was superior and was the way to go. He went as far as to recommend that it would be better to run an open diff instead of a Guard. Bad mouthing a competitors product is a bad way to earn someone's business IMHO. First impressions are very important in my opinion and this was not very confidence inspiring to say the least. I then visited Matt at Guard. Matt took to time to patiently explain his products and what he would recommend for my particular application. He NEVER badmouthed the OTHER guy. That is what impressed me the most as he let his products speak for themselves. I had his Guard Club LSD installed and after over a year of hard track use on my 550+hp car, I have nothing but the best to say about his products. Zero issues whatsoever. I couldn't be happier. Your mileage may vary but this is my unbiased experience dealing with both shops.

cfjan

LOL.. open diff is better than Guard diff.. what a joke...

I am very happy w/ my diff upgrade (w/ Guard internals).. the difference is significant for even a weekend warrior type like me..

Crazy Canuck

Guard. End of story.

996FLT6

Guard - one and only!!! Best bang for buck mod- company and products.... Bar None!!! Mike

GTgears

Gentlemen, thank you for your kind words. We do our best to provide both the best product and the best service out there. It's great when we hear back that you are satisfied.

JohnPG

Matt=Class Act