DRAG WHEEL/Tire setups

Originally Posted by phunk

Theres 2 ways to get this car to hook the best its reasonably going to.

The BEST and proper way, is probably more commitment to drag racing than you are looking for. Small rear brakes, like the 350z non brembo in the rear, will allow a 15" wheel. Use a proper drag slick. Run the softest suspension you can, which means all stock. Align the car to remove as much negative camber as you can. This is the best you can do. And it will do pretty good.

The next best you can do is (when you wont give up your rear brakes)... run the widest and stickiest tire you can, on the smallest diameter wheel you can. This means 305-315 drag radials on an 18" wheel. Adjust your coilover height in the rear back to stock height. This will straighten your control arms back out and reduce your compression camber curve. Align the car to remove as much negative camber as you can (if you dont, all that extra width is meaningless because its not pressing into the ground). Set your suspension as STIFF as you can to prevent as much rear squat as possible. Rear squat is your biggest enemy in this car if you do not have a smushy true drag tire. This should be able to get you 1.9 60's and traction through most of second. Run low pressure in the tires... 18-20 or try a few spots to see what your particular tire likes. You might even get into the 1.8s like this.

The IRS in the 370z is particularly terrible for drag racing and/or hooking up high power. Even the slightest compression in the rear causes extreme camber. This is why you only want squat if you have a tire that is going to severely deform to accomodate this. Your street drag radials will have none of that, and you will be ice skating on the inside corners of your tread any time the car squats. This is my current status.

Hopefully by summer I will have some products finished that adjust the compression camber curve and our Z's on big tires can act like it.

Good luck and try and get us some 10 second time slips. You have the power, just gotta get it out of the hole. I know EXACTLY what you are going thru.

Originally Posted by andre12031948

Doing ONLY 1.9 60' is meaningless. A 600+ H.P. + good turq. should do 1.4-1.6, or don't bother. My old car did 1.6's all day, so I know what that type of car/H.P. should do/must do if you want low 11's, high 10's.

A Nismo is designed for road driving, drag racing needs weight transfer. A Nismo's suspension is too stiff, but with much soft rubber of a SLICK, good drag racing is still possible..........

Originally Posted by GSS138

The only real option on OEM suspension is to move some weight to the back.

Originally Posted by GSS138

Phunk , do the big squishy tires really allow for enough front-back weight transfer that you don't need to soften up suspension? I'm asking I have no first hand knowledge of dragging this car. Are you saying the problem is that if too much load is transferred , this car cambers out too far and you lose grip? How about starting at positive camber?

Originally Posted by phunk

I am saying that unless you have big squishy tires, as in real squishy like a real drag slick, that you not want weight transfer due to the camber this car generates.

Normally you want weight transfer in the back. But that weight transfer does you no good on drag radials because it reduces your contact patch to nothing. Example... If I do a rolling second gear burnout, the patches on the road are about 2-3" wide. My tires are 315/30/18. With stock shocks my car squats a lot, and to make it worse, I'm starting with crappy control arm angles by being lowered a lot on springs, causing the camber to pull in even faster with every bit on compression. If I put stock springs in, I would get more contact as my control arm angles would be better. If I put in real hard shocks, it would get better yet, as there would be less compression to cause camber.

Starting at positive would be ideal, especially if running all stock suspension and soft slicks... But nobody here is going to do it... It's too far into the drag only realm.

What I'm saying applies to this car and this car only (and 350z). Not all IRS cars have this problem... But this is why you don't see many fast Zs. It's rare that a Z owner is committed enough to go to full slicks and small wheels/brakes. But without that.. 1.8-1.9 60' is all your getting. There's tons of 350zs that have had the power to go single digits... You can probably count on one hand how many have done it.

Originally Posted by andre12031948

I stand by my statement. A 600 h.p. car with EVEN JUST SOME traction prep. doing 1.8's/1.9's = sucks......

Originally Posted by andre12031948

I said your post was a good one!!!!!
I was referring to the person that owns that 600+ H.P. car. Also people can't just say that traction can NOT be gotten by a 370 Z. That's crazy, there are cars including ZZZZZ's with much more H.P doing 8's & 9's at the track

OF THE TOP OF MY HEAD.

VINNIE TEN with their boosted car are/did do low 9's. That's my point! 600 H.P. is great but you have much more powerful cars & ZZ's doing 1.4's, 1.5's & I found NO PROBLEM, with my nothing of a car doing 1.6's ....... So fix that problem, don't say we can't.

By the way, 3/10's gain at the start 60' = apx. 5/10's at the finish line!!!! FACT !!!! APX. maybe more????

Originally Posted by phunk

I am not saying you CANT... I am only saying you cant on 18-19" drag radials with this car... CURRENTLY. I am working towards a fix for that.

But yes, with a dedicated drag setup, proper alignment and slicks... ya for sure these cars can hook up great. Its just that its not what people in this community want. They want a full street car to hookup something closer to like what a vette or a viper can do on street tires. They can do it because of their different suspension profiles that do not camber 30 degrees when you try and launch!

If we can get the typical 60's down to 1.7-1.8 on normal 18" drag radials... it will be epic for the 370z scene because all of a sudden we will start seeing people get more excited about drag racing. As it stands, its really damn frustrating to even bother with how poor these cars hook up without full slicks. We need solutions that dont involve changing the rear brakes and putting on 15-16" wheels... and suddenly we will see a greater number of Z owners taking their cars to the track.

Originally Posted by andre12031948

Doing ONLY 1.9 60' is meaningless. A 600+ H.P. + good turq. should do 1.4-1.6, or don't bother. My old car did 1.6's all day, so I know what that type of car/H.P. should do/must do if you want low 11's, high 10's.

A Nismo is designed for road driving, drag racing needs weight transfer. A Nismo's suspension is too stiff, but with much soft rubber of a SLICK, good drag racing is still possible..........