Ok. I made some calls and talked to Tom at TPC Racing who tracks TT cars all the time. He suggested that I go with the adjustable camber plates on top to dial in more there and reduce the shim size on the bottom. The camber specs I have is where I need to be static, but he was worried about the dynamic changes under load where it could stress the CVs, like you guys mentioned. Thanks for the info and the parts are ordered to rectify.

 

Good to hear your'e on top of it Doc. We've read enough horror story's. Btw what did Tom say about the differences in the 996 and 997 arms? Also what was his take on the shim limits down below? I know there really isn't much left to play with down there and the camber adjustment must come mainly from up top. It may pay for Abby997tt to revisit his set up as well. I'm happy to be wrong on this but from my understanding using 8mm shim is sure getting out there on these cars.

 

okay you guys are scaring me!

What's the problem with the spacers at the track?

If I buy only GMG springs or only GMG springs and sways what is the best all around alignment setting for mainly DD use and will the joints etc... be okay?

If I bought springs first and sways later does the car need to be realigned once the sways are put on?

thanks for any answers.

 

The 996 LCAs are shorter then the 997s so it is common to use a slightly larger shim on the 996 version. I didn't find out the actual difference though but will go with the Tarett adj mono camber plates and get most of it that way and fine tune from the bottom. I should be able to dial in -1.8 to -2.0 on the top and get the other -.5 or so from the bottom.

He did like my choice in alignment settings for the car.

 

To be honest Asher I'm unaware of any problems using wheel spacers at the track unless the spacers are causing wheel balance problems from placing the wheels outside of the acceptable offset tolerances. The shims i was talking about were to do with the lower front control arms. I recall slawek mentioning spacers but i think he was referring to the shims on the arms and not wheel spacers? To answer your question which would be the best alignment setting for street i would recommend you talking with the guys at GMG who sell the springs. They would be better qualified for that info. I do know that once you lower the car it is definitely going to need an alignment before leaving the shop as once you lower it, all the previous settings will automatically change.

 

You will be fine either way. You can dial in about -.8 on the factory adjustment which is all at the top.

You will have to realign the front end after the sway bar install. You have to drop a lot of stuff to get it in. You might as well do springs and sways at the same time.

 

Yes i was aware the 996 were shorter if not by very much so was hoping to get an exact difference in mm for future references. The tarret mono plates will definitely provide for your requirements now and into the future although the turning of the existing mounts around should provide what you need now. I'm told it's only once you get over the 2.5 mark that the camber plates become a necessity but either way your on the right track now which is the main thing. 16mm on the bottom is in disaster territory and I'm also not convinced 8 on a set of 997 arms is ok either. The best result is maintaining the stock movement in the CV joints where you can. The only possible issue in having a neg setting of 2.5 mostly from the top is having the top of the wheel sit a little inside at the top of the guard but a set of 5mm wheel spacers will fix that if the look is an issue but i think your rims should have enough additional offset to counter most of that now. I think your choice of alignment is a really good compromise if not a bit more focussed toward track use but anything much under 2, 2.2 the outer edges of the r tires still cop too much of a pounding and you don't get the contact. 2.5 will be better for sure on the track tires and give a broader tire contact on the fronts which is where the majority of wear happens. GL.

 

Just quickly Doc, going by your figures above you should be looking to reverse that i.e. have the .5 neg coming from the bottom shim and the 2 neg from the top tarrets (thereabouts). Always good to know your car won't be coming back on a flatbed and i'd go very easy with those 16's on meantime tho.

 

I considered rotating the stock mounts but Tom did tell me the rubber bushings will allow to much camber change under load so I just opted for the mono mounts. Taretts price is not bad at all for them.

Tom didn't give me specifics but from out conversation I think that the 996 LCAs with the 8mm shim is about the same as the 997s with none. Of course, this is just speculation

Maybe someone has measured them or has pics side by side so we can see.

 

Yep.

 

Yep id agree the mono mounts are the better solution plus your under way there but the stock mount trick does work even if not quite as as good. Agree it'd be great to get the numbers on the lengths....with pics. Always great to have all the fine details associated to the measurements surrounding this issue for future reference. That way alignments can be done by others with precision and without risk to the shafts and diff etc. Alignments are always done with best intentions, but unfortunately without full knowledge of the pitfalls happiness can quirky turn to tears.

Edit. Btw i was just watching that video of Betim's (BBI) a couple of threads under yours. There's a guy who apparently knows what he's doing with suspension set ups. I note he speaks of lengthening the driveshafts to achieve a wider track and undoubtedly a more aggressive camber setting in the process.

 

I just watched that as well and caught that bit of info!

 

Great technical info in this thread. As more and more of these cars go from garage queens to track beasts practical info such as this can help many future track warriors avoid suspension modification pitfalls. I'm gonna sticky this for a couple of weeks

 

Thanks! Glad we (the other guys mostly) can be of assistance!

 

Thanks for the useful info guys. I understand that there are 2x3 permutations for settings on the GMG sways, how do you decide which way to go? I didn't hear back from GMG, they are probably busy. I may call them. The shop I use is known for suspension setup (they do the Porsche cup cars) so they will likely have some input. I'm just basically using the car as a dd with occasional track use and would like to know what sways add to the springs so if anyone has an opinion on that I'm all ears!