Hi:

Been here a while, but don't post much. I have an "all" black 2002 Z06 with about 12k miles. It is in excellent shape; everything works as it should.

I am not a big street accelerator, but sometimes I partake a tad when things seem safe enough--like in the near boonies. I have a 3.73 rear and run BFG drag radials in the factory size. Before installing the 3.73, I could get very nice minimal wheel spin starts with virtually no clutch slippage--which is what I want to do--having no desire to burn my tires off too often or to fry my clutch.

Given the 3.73, I am having trouble not "going up in smoke" when I start unless I do more clutch slipping than I want. I am looking for a solution to this problem not including doing a minitub and getting fatter/heavier wheels/tires (i.e., I want to keep the car's body unmodified; to use my factory wheels; and to use at least close to factory spec tires).

I wonder if a cam might be partially instrumental in solving my problem. I am thinking that the proper cam choice might help reduce my low RPM torque sufficiently to help with my problem and at the same time increase my high RPM torque enough to, of course, provide quicker acceleration. I also wonder if the right header choice might have a similar or complimentary effect. When it comes to headers, I would only consider strictly bolt-ons. And, I wonder if I might fare better with CUPs tires or, alternatively, with Hoosier r6's. I think both come in 295/30-18--which is pretty close to factory spec.

Dumb ideas? Any thoughts? All help appreciated.

 

Exactly why I say not to do gears but people on this board love gears. Especially since the z06 trans is geared like a 3.90 rear end.

 

i don't think a cam or boltons is going to help keep you from spinning your tires, if anything it will just make it worse... they are called power adders for a reason... if you wanted less power/torque you could go backwards and get an ls1 cam/heads or something like that, but honestly i don't know why anyone would go through that much time and work to lose power

 

buy a mustang.

why do people whine that a car designed to go around corners and stop has a hard time hooking up when launched aggressively?

 

Nice and really knowledgable people here these days. Why waste my time with these posts? Anyone interested in not saying Bozo things?

 

Getting stickier tires is going to be your best bet. There's no point in swapping in a cam to make less power/torque.

 

why not just go back to 3.42's? but what is it that you want out of the car? i have a buddy as well that did 3.73 in his 03 c5z and he absolutely regrets it. only reason why he hasnt swapped back is cuz he spent all that money and now is just convincing himself its not too bad but overall he hates it, just a matter of time before he takes it back in.

 

Maybe lower compression and turbocharge.......expensive, but might give the logarithmic acceleration you want.

 

I think you know the answer, but just don't want to admit you wasted your time on the gears.

Try launching at a lower RPM out of the hole.

Going to a cam big enough to drop your low-mid range torque is going to be unenjoyable to drive on the street in my opinion. Headers will increase torque at all RPMs.

I guess you could put a base C5 tranny in which has better gear spacing and would bring your first gear back close to stock as well.

 

R compounds, MN6 trans swap, back to stock gears, or get used to second gear starts. Last thing you want to do is back power out of your motor to compensate for the tourque multiplication of the 3.73's. Be thankful you didn't go 3.90's or 4.10's if the 3.73's are too much for you.

 

I'll start with the tune, an adjust timing to make the power to where you want it, might be the cheapest option

 

Your no-cost option is more throttle control and a lower launch rpm. A more expensive option is to revert you gears back to stock. An even more expensive option is stickier tires.

I've never heard of anyone doing a cam job with the primary intended effect of decreasing low-rpm torque.

 

Don't take this the wrong way, but the more I think about this, the more I think you just need more practice. It sounds like your car is stock or nearly stock. Drag radials can handle that power - yes, even with 3.73 gears - you just need to feather the throttle a bit instead of stabbing it to the floor in first gear.

 

Is this a serious response? He's having traction problems and you want him to add a turbocharger??

 

I thank those of you giving replies aimed at being helpful very much. Some have indicated/implied that the gearing is too low. But, consider that the gear change gives only about an 8% to 9% increase in rear-wheel torque which is not too different from what might be provided by bolt-on upgrades andy dyno tuning--which commonly are done.

I also want to mention something I ignored earlier for simplicity. I have had a change in location. And, the new-location asphalt is much slipperier than in my prior location. I seldom had a problem with my preferred street-start procedure in my prior location. I also have a 2008 M Roadster, and I now even have some traction problems in that car.

Some have implied/indicated that I don't like my new gearing. Not true. I have a problem with it, but really like it much better that the factory gearing--except for the one problem.

Perhaps I need to change my street-starting procedure a bit as mentioned above. Recall that I like minimum wheel spin sans clutch slippage for the street. Perhaps I'll have to add more clutch slippage as suggested. Maybe I'll just have to get over having to slip the clutch.

And, maybe I'll try the Hoosier tires I mentioned, although I am not sure they would provide more traction than my drag radials. I certainly agree with the response that drag radials can handle my torque/horsepower. I don't think I would have a problem on the strip, but the street, at least in my current location, is a different matter giving my preferred starting procedure.

Judicious tuning also might be a possibility. I'll think about that too.

 

Start with learing/figuring out a new launch technique. Changing this/that is only going to make you learn yet another technique. You say you like the rear now, well learn it. Are you warming up the drag radials enough? Good luck.

 

The best and easiest way to improve starts is to go to a 17" rim and run 315x17 drag radials. They will fit under you car and with the increase in tire with and better side wall flex you should see a big improvement. allot cheaper than the other choices. Go with the tire manufacturers recommendations for wheel with. I run 17x12.5" rims with a 335x17 A6 Hoosiers under stk wheel wells, that would be too much for street applications.

 

Put some skinny tires on it if all you want to do is make a lot of senseless smoke.

 

Thank you for the recent suggestions not counting the last one.

 

I dont know why guys mess with there cars, GM did a nice job on the Zs from the factory, I have a 02z and would not change a thing, JMO