StealthFox

iTrader: (2)

when i launch my car it just shakes super violently like im riding a bull or something(not sure if im actually getting wheel hop or if my car is just jolting really hard) and breaks traction a little but by then im close to redline and need to let off or shift, my tire pressure is on the low side(28psi rear) but before when i had it at 34 it was like that too. is this a common problem with FD's? it bothers the hell out of me because i know its extremely hard on the drivetrain and LSD, how can i get rid of this aside from upping my tire pressure and increasing my spring rates?

silverTRD

iTrader: (37)

yes its a common problem with fd's. and its really not a good idea to let the car do because it can wear out bearings and all that nonsense. not too cheap either. you could always get a launch kit...

nashman69g

iTrader: (3)

there's a couple of explanations of this...to find out in more detail search...its probably worn out diff bushings...

KaiFD3S

iTrader: (37)

Check bushings and suspension...Mine used to do the same thing, but when I switched to the buddy club coilovers problem dissapeared

13b4me

You're supposed to ride the clutch when you launch anyways... If you're dumping the clutch, you're gonna get wheel hop no matter what RX-7 you're driving...

BobfisH

I dont agree 13b for me.

If you REALLY want to eliminate wheel hop, polybush the rear of the car (diff bushes especially) and get a launch kit. Install a diff brace, and off you go.

If you want to cheat and just calm it down, get a diff brace.

StealthFox

iTrader: (2)

for sure i had a big feeling it was my bushings

im gonna be lookin into polyurethane bushings for my entire suspension and rear end, notably the differential bushings(thanks bobfish)

ive known about the launch kit, and i see a few companies have htem but none reccomend them for the street. if anyone that has them can tell me how terrible the ride quality is, let me know. anyways, what exaclty makes up a "launch kit" i dont like the idea of "kits" id rather get the parts from companies ive heard are good rather than buying a "kit" it seems the essense of it is basically reinforced solid trailing arms, reinforced upper control arm bushings and differential mount bushings but a lot seem to be made with delrin, and since my car is daily driven, i bet that will cause a heavy toll and strain on my chassis?

and bobfish, where would i get a diff brace?

and can anyone reccomend a good full poly sus/diff bushing set? id be willing to spend $$$ to tighten up the suspension b/c after 13 years of hard driving, these old cars are all worn out, and i know from one of my friends cars new bushings rejuvenates the suspension a lot.

StealthFox

iTrader: (2)

yeah im eventually going to get reinforced sway bar mounts, 10kg/8kg springed coilovers, and the mentioned poly sus/diff bushings and probably a diff brace and solve this problem. i had a feeling that this was common with these cars, i havent been into FDs in a long time, i used to like them when i was younger but when i got into FC's i forgot all of that **** then now i end up with one and dont know jack **** :\


what the hell, my n/a FC i could just dump that **** at 5k and smoke em out good, my current car makes twice that power and im having problems launching good

Alcoholic

what exactly is happening during wheel hop?

13b4me

Ok I should clarify my previous statement... I've always experienced wheel hop when dumping the clutch, and in fact I even broke a subframe mount as a result of it... RX-7's are rather light cars, and unless you have a well engineered suspension setup, they are terribly prone to wheel hop...

Try revving to about 5-6k RPM's and just "feeling" the clutch out... When you feel the power start to transfer to the wheels more and more, you release the clutch accordingly... It's the only way to get a decent launch on street tires... It's just too much power going to such a light rearend, and when it's applied suddenly, the wheels tend to fight for traction...

It also depends on the RPM's you launch at... Of course revving it to 7k and dumping the clutch will get you spinning quickly enough to avoid it, but 7k is obviously too high of an RPM to launch at unless you're running slicks...

The idea though, is to transfer the weight gradually to the rear, which is best done by riding the clutch out...

airborne

I'm going through the process of eliminating wheel hop. I've got koni shocks, eibach springs, toe links, and trailing arms and none of that changed anything. I've got a set of rx7.com diff bushings to install and that should do it i hope. there's tons of threads on the subject if you search.

here is a wonderful example of me demonstrating wheel hop. the 2nd launch that is.

http://www.panekmechanik.com/Videos/...cil%20Sept.wmv

ratincat

i still get wheel hopp and i have ubtonum diff bushings re toe links and triling arms a diff brace and a kaaz 1.5 diff ohh and apexi exv coil overs any explantion for this could i adjust the traling arms to be a bit longer to help with the unload load situation

silverTRD

iTrader: (37)

that launch makes me cringe. not a bad time though...

akiratdk

I heard from a Japanese Rotary Engineer.... that if you stiffen the rear too much you are prone to breaking the diff more easily. I don't know if its true or not but he was saying when the rear starts to shake just ride the clutch.... hope that helps.
Mine shake like hell as well... I had poly urathane diff mounts and when I changed back to stock... I broke my diff so I changed it to another one I noticed that the shake got worse.
So I do believe the poly mounts do work to some degree... but it doesn't completely remove the wheel hop.

StealthFox

iTrader: (2)

actually i totally understood what you were saying in the first part of your last post about riding the clutch and on my way home from school at all of the stoplights i was trying that out and it works FANTASTIC very easy to do and MUCH MUCH smoother. i have a lot more control and can just lay on the power much better, thanks for the tip. it seems like thats a much better technique for these cars, dumping is just too hard on them. they're not designed for drag, they were designed for high RPM power and handling/track use and you just cant launch them like a big heavy big displacement muscle car unless you set them up.

DaveW

Just be careful that you don't slip it so much that you overheat it and burn it up. Even if you don't burn it up, it will wear faster slipping it. However, that's certainly better than breaking the diff or some other geartrain part.

StealthFox

iTrader: (2)

man thats painful to watch, and i cant believe with those things you still get wheel hop, i would think that the springs and the rear arms alone would help a lot...it seems the major thing is the solid diff mounts.