916LS1

iTrader: (4)

Just got back from the track where I had NO traction at all. It would just sit there on the line spinning after a 2K RPM launch, and even a little once at 5K RPM in 1st gear. What can I do besides slicks to gain a little more grip? My 285/45 GS D3's are near new, and my suspension mods are as follows:

Koni SA's (Full Soft)
Hotchkis sways
BMR LCA's
BMR TA
Tires at 24psi

Any other ideas???

Studytime

iTrader: (15)

You could try less air pressure even still. Maybe try 20 psi. Have you ran them at higher pressures just to check traction?

Are you doing a burnout? Heating a street tire will make them very unsticky.

The real solution is a better tire. Even someone else's worn out Nittos on a spare set of factory wheels would make a world of difference.

Back when I had a completely stock suspension, just bolting on a set of 27" ET Streets allowed me to dump the clutch at 6600 rpm and dead hook! I was cutting 1.75 short times with boltons in my full weight daily driver.

Ben T.

916LS1

iTrader: (4)

Thanks Ben, all good advice. I've tried with & without burnouts with no differences. More air pressure was in the back on my mind as well, but haven't tried it yet. I am also a full bolt on minus the pulley, and I think my best 60ft was 2.2XX. I can drive the car EXACTLY how I want at ANY time, but still can't break 13.4 ET's. I am a little worried about if my stock drivetrain will even take say a 5K launch on ET Streets...but I guess thats for another post...

Studytime

iTrader: (15)

There's also this... you have an aggressive clutch that is not designed to be slipped. It's generally more of an on/off switch. I know, I've had a Spec Stage III clutch. This would work really well for you if you were able to hold your revs at, say, 4500, and then come off the clutch. Roll out a few feet and then go WOT. Of course, this would need to be on slicks, but you don't have slicks and you'll shatter your 10-bolt. I know, I've had a Spec Stage III clutch.

To get good times on street tires, you'll need to ride your clutch out at the line, but right now you have a clutch that can't really be slipped. It needs to be revved up and dumped.

It's a difficult situation to be in. If you rev it up to 2000 RPM and dump it with a drag radial, you'll probably bog (but get good traction). This might be your best bet. If you rev it up to 4500 and dump it on a drag radial/slick, then your car will run like it should, but you risk breaking.

I see sort of three options,

1)Drag radials and "moderate" launches using "moderate" shifts
2)Slicks and a strong rear
3)A factory clutch (LS6) slipping the clutch at the line (using street tires)

Keep in mind I'm only one person, and this advice is free. I'm not a career racer, nor do I own a shop that builds race cars.

Ben T.

soulless

iTrader: (3)

I noticed your car is lowered. Do you have LCA relocation brackets? From what I've read, they can really help on a lowered car, as far 60' times go.

Studytime

iTrader: (15)

Certainly worth trying if you don't have a set. You want the front of your LCAs to point "uphill". This will move the IC back further on your car and will transfer more weight over the rear axle helping traction.

Ben T.

916LS1

iTrader: (4)

I don't have the LCA relocation brackets, but thats something to ponder. Can I use my existing BMR LCA's with the relocation brackets? Essentially, it really looks like there is no other way than getting ETs and a stronger rearend.

SeriousPWRTRIP

yes, you can use your BMRs with the brackets. Matter of fact, BMR makes some relocation brackets themselves.

sixvi6-camaro

iTrader: (9)

Sounds like you are running high spring rate springs, hard dampenined shocks (koni's on their softest setting are still way stiff) and super stiff sidewall tires. Your car is setup to go around the twisties. Getting a car to hook and go straight needs weight transfer front to back which is something that your stiff everyhitng setup won't allow. but as was mentioned if you get it to hook it may just shatter the rearend so it may be a good thing to have traction problems unless you are looking for a new rearend.

May Spin

That 36.5mm bar up front isn't helping, unbolt the endlinks at the track. Then the 25mm rear will come in to play alot more.

Sam Strano

iTrader: (41)

Eagle F1-D3's..... a very stiff sidewall, handling tire. Not a drag tire. You can do what you like, but if your tires aren't the right ones for the job at hand, you'll have trouble. After all, it is they, and only they that contact the road.

I don't have any idea what springs he's on. And that could be a problem if they are some of the crazy stiff rears that some companies make. It's not his front bar. You have to get some sort of traction to lift the nose in to start with for the front bar to be hurting. Sounds like he's not. And it's not the shocks. The rear Koni's are not stiff on compression, and when turned full soft in front are quite soft--and again, if you don't have enough mechanical grip to start with, the shocks won't matter anyway.

I'd say change tires. LCA brackets might help, and are cheap starting @ $59 for a set. I don't use them a lot because we are more into handling than drag racing around here, but we do carry them because I know that other people have other goals.

8GTOKLR

iTrader: (6)

Its the tires and not having relocation brackets. I cut a 2.08 sixty with 245/40/18 W speed rated falkens at stock psi of like 33 and half tank of gas. I have about 380 to wheels. mods are:

UMI LCAs, STB, PHR
MAC Sfc
Stock 10 bolt, stock torque arm, stock engine and tranny mounts at the time
stock springs, F&R swaybars
Last but not least my awesome Monroe sensa tracs

916LS1

iTrader: (4)

Thanks Sam. I'm on the Eibach pro-kit, which I thought had fairly soft rear springs. Will LCA brackets negatively affect my handling? My car and I DO have a bit of an identity crisis, I'd like it to be a good all-around car, but it looks like most of the mods I've done for handling have killed my drag performance.

8GTOKLR

iTrader: (6)

Thats where having fully adjustable spherical suspension would come in

y2k_ta

iTrader: (80)

If you went on a "street legal" night, more than likely there was little or no track prep. Track prep makes a big difference too.

Dal1as

At 24 psi those tires are cupping. That's one of the reasons you are not getting traction. Run them about 30 to 32 in the rear and about 38 to 40 in the front (at the track)

Not sure what your hp/torque is but I have koni adjustables all the way around and Strano swaybars and have no problem whatsover with traction on the D3's.

Also, pretty much an street radial is goingto spin by dropping the clutch at 2000 rpms. You have to slip it a bit.

1. Raise the tire pressure back up.
2. Slip the clutch a bit from around 2500 to 3000 rpm.
3. Or go to DR's but you're rear may blow up.

Trev_SS

iTrader: (17)

you need to get lca relocations that is pretty much your problem since you say that you are lowered

916LS1

iTrader: (4)

I'm definitally going with the LCA relocations, but only after I get the now leaky rear diff fixed and a new strange rattling sound from the back eliminated.