Best way to improve rear susp for launches?

[thespeedfactory]

I am running eibach springs and billy sports on the e34. I went to the track last weekend and with all the weight missing the rear susp is stiff as hell.

What advice can you give for softer rear in the e34? Besides tubbed and solid axle...

Maybe just put the stock springs back on? Interested in advice.

I will be running 27x10 Hoosier 3035 asphalt slicks on 15x8 weld wheels.

HX55 1.6 bar at 5500ish and less than 3K# for weight with driver and full cell.

3K RPM launches and pulling deep in 4th at the 150 meter mark. 4.27 LSD rear end, 260/5 transmission.

[Turbo Charg Dynam]

I am running eibach springs and billy sports on the e34. I went to the track last weekend and with all the weight missing the rear susp is stiff as hell.

What advice can you give for softer rear in the e34? Besides tubbed and solid axle...

Maybe just put the stock springs back on? Interested in advice.

I will be running 27x10 Hoosier 3035 asphalt slicks on 15x8 weld wheels.

HX55 1.6 bar at 5500ish and less than 3K# for weight with driver and full cell.

3K RPM launches and pulling deep in 4th at the 150 meter mark. 4.27 LSD rear end, 260/5 transmission.

You need an appropriate diff ratio and tire before worrying about suspension.

You tire choice is an oval track tire. It's not going to work. A 4.27 ratio is ridiculous. Try a 346 or even lower. Heck a 2.82 would be better than a 427.

[thespeedfactory]

The only track here in Okinawa is a 150 meter track with crappy asphalt/concrete for surface.

I am setting the car up for the next 3 years for competition on the surface/length here. The 4.27 is perfect here. I am crossing the 150 meter mark deep in the power band and third gear.

In the US I would have a different rear and et drags. THe et drags on the surface here still have limited traction. VHT is illegal.

The track here sucks and is short. I need info on the best suspension for what I have to work with.

[Turbo Charg Dynam]

The only track here in Okinawa is a 150 meter track with crappy asphalt/concrete for surface.

I am setting the car up for the next 3 years for competition on the surface/length here. The 4.27 is perfect here. I am crossing the 150 meter mark deep in the power band and third gear.

In the US I would have a different rear and et drags. THe et drags on the surface here still have limited traction. VHT is illegal.

The track here sucks and is short. I need info on the best suspension for what I have to work with.


The shorter the distance the more important the first 60 feet. Gear/rpm through the trap is almost irrelevant.

[thespeedfactory]

I have a 2.6 60' with a 1500 launch and wheel spin/~75% throttle.

[MrBlonde]

You don't want a soft rear end, you want a hard rear end. A short ratio diff is an excellent idea provided you resolve your traction issues. Drag racing is all about acceleration.

You don't resolve your traction issues by reducing gearing in your diff to avoid wheel spin. You resolve your traction issues and take advantage of your short diff gearing.

[thespeedfactory]

Roger that. I will see what the change is with tires only. The rear is stiff enough that when I (6'4" 225) push on the trunk with all my weight it doesn't move at all.

Looking to run b class here. Only problem is all of my competition is 700-900 HP AWD GTR's. They are only running B class and 2 in A class.

track is 150 m/surface sucks

A= 5.5 sec and faster
B=5.5-6
C=6-6.5
D=6.5-7
Open=7 and slower

[ZimDoc]

Get different tires, slip that clutch hard and get ready to break something!