ace996

About six months now with my love, an '02 EB/MR Z06 with a Magnacharger (actually quite the spice for autox and trackdays).

I'm planning on addressing the suspension for next year's autox season (and HPDA days). I don't have the funds to go the whole schebang but the sways should be good and I'd like to compensate for the extra weight of the maggie with stiffer springs. The car currently has the '04 shocks (added by previous owner).

With the extra 80-100lbs sitting on the front of the car, I'd think a rise in front rate could help but I don't want to overpower the '04 shocks and cause more problems.

So...any ideas for a maggied-Z looking to cause some trouble in SM2???

Some backup info...
275x17 Kumho 710s front
315x18 Kumno 710s rear

Pretty aggressive alignment
camber -2.3 front, -1.3 rear
Toe out front 1/8th total
Toe in rear 1/4 total

No real oversteer/understeer issues...other than heavy throttle.

Thank you,
Tom

ace996

TTT...

Easier question...

Can the '04 shocks handle stiffer springs? Any idea at what rates?

thanks,
Tom

ace996

I guess I'm in unchartered territory here, huh?

Nobody??? Anybody??? Bueller???

Solofast

If you increase the front spring rate you are going to have to increase the rear roll stiffness in some manner to keep things balanced. When they went to the ZR1 in the C4's the increased the rear sway bar rate (and coupled that with fatter tires to help put the power down) You might look at the Halverson C4 chart to get an idea of what they did for the ZR1 simply because that was a similar amount of front weight increase and that would be a good starting point. With an additional 100 pounds in the front I would think that you would feel some push anyway. Not sure if the 295's are still available in the V710's. I was thinking that they were discontinued. Most folks didn't find any difference between the 275's and 295's up front, but with the extra weight more front tire might help.

Also, you are still lighter than a C4 in the front, so maybe it can still work on the 275's...

Talk to RAFTRACER, he may be able to give you some ideas as to how far to go on front spring rates, and then tune it with more rear bar or springs.

BrianCunningham

You're above the ci limit for FI engines ( 4 liters ), so that will put you into E-mod. You might be able to run full slicks. You can get a 315/335 combo on your car.

ace996

Thanks for the input, guys. I figured a slightly (or more) increase in spring rate up front could help, and I do plan on mounting up a set of bars (T1 or Pfadt...leaning towards Pfadt due to adjustability to help dial-in).

EMod??? I was told by a few, including my local SCCA, that the car would be SM2...oh well, doesn't really matter as I still shoot for FTD anyways...and the SM2 guys are usually the ones battling for that anyways (highly modded Evo8s).

OK...back to the spring issues -
How high can one go with spring rate on the '04 shocks without danger of blowing them out? Or would Koni single adjustables be needed?

Thanks again,
Tom

see5

VBP will build you a spring almost to spec and running 315x17s on 10+" rims is very doable. The VBP spring is very flat in profile (unloaded) compared to stock or T1 spring.