Thread: B14 rear trailing arm movement?

............Its called progression. Also, some classes only allow a chassis up to a certain age, so you are forced to "throw em" in the trash regardless of if the car is fast or not

Also, the DOG II car is still running over the California and still sets VERY fast times (when Mike can drive as he has so many commitments) and the DOG I car is driven by several other drivers (with the most recent being Dai Yoshihara). Actually come to think of it, it ran as recently as a month or two ago in the MPTCC, so not quite trashed. Actually quite the contrary .

The 2J car I saw as recently as April during a local trackday at Summit. . That BEAM car still holds several records at Road Atlanta as well

Only people who hate cars are able to tame the monster known as the BEAM

Mechanically bent it, I don't have a torch hot enough for heating (MAP w/oxygen doesn't cut it still).



Hank wasn't bashing the beam in that post, he was talking about the SRL only, two different animals. Beamed cars when setup right will be better then McPherson IRS setups. See the BTCC Top Secrets article

Vadim, I know he was not, but ze interwebz no convey jokes good

............Well this thread took longer to take a shit than previous threads. It must be some sort of a record

After you get some miles on that beam be sure to recheck the toe. Joe was telling me he's seen more than one mechanically bent beam go back to being negative toe after some use. That why he uses the heat/shrink method, instead. The heat gets rid of any memory the metal has the first time.

Ha funny that you say that, someone I know used a torch to get the toe out, when it cooled it sprung in a bit though. So next day he tried using map + oxygen, and it actually sprung in even more toe in.

Sadly these beams bend easily, but that's the whole purpose of the twist beam setup. This is why even a beam reinforcement bar, aka ADCO "swaybar" still makes a huge difference.

It's a lot of welding but you could always do what these guys did:

well initial turn in it feels like the back end keeps going straight, just barley noticeable, feels fine mid corner, then coming out it feels like the front straightens out before the rear. feels like im snaking around if that makes sense. and like i said its barely noticeable. i just notice my friends 240s feel more solid taking corners than my car, like the back end stays put like it should. i havent driven the car in over three weeks due to a JGY clutch failure, no surprise. should be running this weekend so ill drive it and check everything in the SRL. maybe have a update on the cause

how do you jack the rear end up then?

After thinking about it more i think the rear end might just be rolling more then the front around the corners giving me the feeling that its snaking like the trailing arm is shifting, when really its just not as stable like you and hammerin hank said before. the rear springs are only 8k compared to the front being 10k, and i know that the same or stiffer springs work better in the rear.

anyone know how what hight i should raise my car to thats best with the roll center and where to reference the measurement off of? i cant refer to the stock hight because i went from lowering springs to coilovers and i have no idea how much lower the car is from stock

P11 has two notches that are reinforced towards the middle of the car, I jack both sides up using them. B15 doesn't so it kind of sucks, but it does have wider frame rails. I just jack it up in front or middle of the car and rear comes up no problem.

10k and 8k??? Wow that's stiff. I feel like my 4k's are too stiff for street driving.

You will have to do the math for the ride height. If you bring up your FSM, it will tell you the wheel arch heights for stock xyz car. If your running exactly the same tires as stock your job just got easier. If your not, then you need to get the % offset from stock tires, and apply that percentage to the FSM stock heights, and that will give you what your stock height should be on your current tires. This one is hard for me because my fenders are rolled and lipped....

As for ride height, if you keep both under 1" lower then stock most problems go away. Basically raise the rear until the beam is no longer shifting, that's thrust angle degrees on an alignment rack.