DansBlkonBlkZ06

I've recently installed single adjustable Pfadt coilovers with non-adjustable T1 Sway bars. I'm having a hard time with the rear being too stiff and trying come out in most turns at CMP this weekend. Shifting 3rd to 4th at bend after Turn 8 even gets the rear to come out.
I've tried everywhere from Pfadt recommended track settings to street settings and am having no luck. The front feels very good at 2 clicks softer than recommended track setting and a little higher air pressure. Is the rear T1 just too stiff with the coilover setup? The softer rear settings seem to help some but it's not as stable as when I had it all stock. I'm considering putting the Z06 rear sways back on to see what that does. Does anyone have a similar setup?
I'm running good tread on R888s for DE sessions and R6s for time trials.

DarkMastyr

What are your alignment settings?

redtopz

You should be able to make that setup work. I ran the exact same setup in hpde for a year or 2. The rear needs more shock rebound. Ideally you would get slightly stiffer front springs. Make sure to keep the T1 sway bar bushings well lubed and spaced out with washers or they can bind up and act effectively much stiffer. I found the T1 bars to be much better than the stock bars on the track. However, it won't hurt to try the stock bar in back for a while.

Rookieracer

What do your shock travel indicators say?
Any chance your bottoming the shock or perhaps a bind in the rear suspension somewhere?

DansBlkonBlkZ06

My alignment is -2.5 camber front and -1.6 camber rear. There is plenty of lube on the new bushings and I put spacer washers to get the bar to move somewhat freely when not loaded. There were no strange sounds from back there, so I don't think it is binding any.

DansBlkonBlkZ06

Also, the front T1 sway is massive. Although front feels really good, could the stiffness of the front be affecting the handling of the rear that much?

0Xplosive Performance

Is the rear coming out on you on entrance into the corner (under braking) or at exit when you apply power? If you want call in the morning

Saucee

Would you explain the remedies to both of these? I just had my new to me Z06 out at Big Willow last sunday, man is the thing loose. Getting the pressures right on the sh*tty PS2's helped entry a ton, but it was still all over the place. I have Pfadt coils as well w/ Johnny O'Connell sways. I was going to soften up the rear bar and dampers but I'd love to hear your input first.

Pfadt Racing

Give us a call when you can and we will get you dialed in!

2MCHPWR

in my last 2 c5's, I ran the T1 front bar with a stock z06 bar in the rear.

DansBlkonBlkZ06

I've heard several that run that setup. With coilovers at very soft settings and rear end still coming out (mainly at acceleration coming out of turn), I am going to try Z06 sway with stiffer coilover setting. I will report back. Thanks for suggestions.

brkntrxn

Dan,

How old are your tires? How many heat cycles? CMP is such a "stupid" surface that you may just be feeling the tires letting go. I have had tires that were perfectly fine at RRR the weekend before that were junk at CMP and then decent again at VIR.

Before you start changing parts, confirm the tires are not bad. Did you rotate them at all during the weekend? Swap fronts and rears?


-Kevin

DansBlkonBlkZ06

Tires are in decent shape. I had them rotated on rims last week. Pfadt says to try softer setting and see how that works. My next event is at VIR. I know CMP is so different than VIR so setup may be fine there. I'll bring Z06 sway just in case since its a quick swap.

brkntrxn

Which event?

drivinhard

This

Unless you're running some major event at CMP, I wouldn't spend 1 second trying to make your car feel good there. You can go set a new track record at VIR or RA the weekend before, not change a thing, roll in to CMP, and you'd swear somebody ran all the clicks on your shocks to the other end, put 3/4" of toe out in the rear, and let your tires down to 7 psi. You're always chasing the car there.

Zenak

Autocrossing: I likes it soft on those
Road Racing: I liked it super stiff on that set up

I typically was about 2 click F:R different in the dry on RR, and I sooftened up the rear in the rain to be about 4 clicks different F:R