mspiegle

Also, if you want a cheaper tire that's still pretty good... checkout the Nitto 555r. You can definately drive these around on the street and they're very sticky.

all4woody

Thanks for all the input, let me see if I can answer a few questions.
1. "BTW, what gear/RPM were you at when you hit the traps?"
I am just hitting 4th before the trap, usually 110-112mph. Not sure about RPM
2."I am running the same HP (you at 10psi also?). "
I am at 7.5psi but will soon be going to 8.5.
3. "What year is your S4? "
It is an '89 S4 5sp, LSD, Koni externals, Big Reds, Sway, Rollbar, 6 point harness, Recaro SRD's, Forgeline 9 & 11x17, twin-screwed and intercooled. Kevlar clutch. 154K on the engine. POS stereo.
4. "You might consider heating your tires a bit more"
That was my first time at the strip, I have gotten a little better at warming up the tires.

Thanks alot for the advice, I will go to Tirerack and see what they have.

Have a nice day, Woody

Tony

Great Videos! I love the view on the last one!

you need a longer burnout Woody, seriously. Street tires need all the help they can get. I drop my 18's down to appx 19psi and do a pretty much a brake stand in the water pit then ease of the brake and let them continue to spin into the dry part of the staging area.
They still spin of the line but i see a noticeable difference in my 60ft times if i dont warm the tires up. You can can feel the back of the car getting soft as you hit appx 90ish with the lower pressures.

Great sound and good runs!

What are your 60ft times?

http://members.rennlist.com/v1uhoh/tonysharkrun.wmv
(the format it was filmed in is 16:9...hence things look bit squished)
thats one of mine...
My best has been 12.9 on the streets tires.

m21sniper

" I am just hitting 4th before the trap, usually 110-112mph. Not sure about RPM"

Ideally you'd switch to a lower gear(ie a higher numerical ratio), but given your traction problems, a higher gear(ie lower numerical ratio) would actually greatly aid in your launch traction by reducing torque multiplication.

If the BFG drag radials don't get the job done for you, a 2.20:1 ring and pinion set would help a bunch(of course that will cost BIG bucks unless you can find a good used unit to swap in).

928autobahndreamer

Is it just me or did you have a passenger during all of those runs. Dropping a couple of hundred pounds for the run may also help a little.

all4woody

Yes, I had a passenger for those runs, more weight equals better traction...right? I will get Sam to video me next time out, my runs have gotten better.

Tony, my 60' are 2.029-2.264. I have no idea what that means. My best race last weekend went:

R/T ... .227
60' ... 2.027
330 ... 5.469
1/8 ... 8.276
MPH.. 88.68
1000. .000 (did not register)
1/4 ... 12.729
MPH .. 110.96

Hope that helps. Most of my slips are between 12.7 and 12.9.

Have a nice day, Woody

m21sniper

Those 60 foot times are pretty weak for a car in your power level, which verifies the bad traction issue. You should be in the 1.8sec range with good traction.

You shoulda had the passenger lay in the back.

Crazy as it sounds, i think a 2.20:1 rear would really help your cause if you're running the 2.5 or 2.73 ratios.

SharkSkin

I'm not so sure taller gears are the answer. If the wheels aren't slipping, the clutch is. I think what he needs are stickier tires and finer control over wheelspin. Too tall on the gears and it will be a clutch every weekend instead of a pair of tires. Which would you rather change?

Now if he had a torque converter I would agree. My old '67 R/T had 2.72 gears and a Torqueflite. With 3.23 gears I would just light 'em up for days, so I switched to gain traction. My only other option was to tub the wheelwells and get some big meats on there. When the converter locked up it felt like a turbo coming on boost! I only got it into the high 12's though... Hitting the traps at 130+ in 2nd gear! The torque multiplication can really make a huge difference when you've got that much grunt!

m21sniper

"The torque multiplication can really make a huge difference when you've got that much grunt!"

Yeah it can. My T-Type had a TH350 swapped in, and with a 2800rpm stall converter running 3.73 gears and launching at 10psi of boost it really launched like a missile.

I get the feeling that if he gets traction from a tire change he's going to toast a stock clutch pretty quick anyway.

Going to a taller gear would actually reduce the stress on the driveline(assuming equal traction) because of the torque reduction in all gears(but particularly in 1st) vs a 2.5 or 2.73 unit, as well as making it a lot easier to get the traction to begin with.

There's no free rides, and when/if he gets traction with the current setup, the stresses on his driveline are going to be ummm....severe. A taller gear would actually reduce those stresses by about 15% or so(depending on his current ratio).

IDEALLY, for drag racing he should be running a 3.55 or thereabouts, but that would be very hard to get traction with sans a full tub/slicks, and would really stress the drivetrain, and no one makes that low a ring and pinion for our cars anyway.

I love my 2.20 geared A/T for dragging. At 30psi in the rears(which is the pressure i run on the street) i just stick it in drive, rev to 2000rpm....yellow, yellow, little chirp, and hold on.

In my best ever run i hit the traps just after upshifting to third at 103.1mph(13.67ET). That run was accomplished staging at 1800rpm with 16x7" rear rims running 245/45/16s at 20psi, 50psi in the fronts, and 1/8 tank 100 octane cam II racing fuel, and about 100lbs of weight savings ago. I've since switched to 16x8 rears(same tire size), and i can now rev to 2000rpm with the same traction (but at 30psi!) as before at 1800rpm/20psi on the 16x7s. Combined with the add'l weight savings, i figure i'm probably capable of a 13.5 in 'race trim' now, or a solid high 13 in 'street trim'.

Drewster67

Great Vids - thanks for posting.

SMTCapeCod

All you need to do is to figure out how to get a torque converter in there, right?
Just kidding...traction limitations are both fun and frustrating! I'm having an interesting time looking at the power procution vs 60' and 1.4 mile times on the blown 928s vs the 3000GT VR4s. AWD makes a heckuva difference as the videos indicate! Taller gears may cut down on the wheel spin, but I think if it were my car I would rather keep the responsiveness and torque multiplication even if it costs a couple tenths worth of bragging rights. but thats an individual decision -- and one I don't have to make since forced induction on my Euro's compression ratio seems unlikely to meet my bang-for-the-buck threshold (not that I hve the buck- got bigger turbos for the VR4 instead for 1/5 the price!)

vs.

m21sniper

From what i hear 1st gear in the later lower geared cars is actually not all that useful anyway. With a 2.20 rear it pulls in first all the way past 50mph, and my 2.20 first gear is actually giving much greater torque multiplication than a 2.73 car in second does.

As Mark Kibbort likes to point out, it's all about average acceleration...and the 2.20:1 cars are very strong in that dep't.

SharkSkin

Good points Sniper(Mike?). Unfortunately, making a gearing change calls for a complete transmission rebuild or replacement....

m21sniper

Bill.

Gotta agree about the practicality aspect of it, from what i've read the 5spd cars need a total rebuild to change the ring and pinion. A good used 5speed unit out of an S4 would work, but of course it wouldn't be cheap.

All about the money, as always.

all4woody

This is a 5 speed in an S4 with a new Kevlar clutch. It is mainly used for weekend driving and PCA events, but after I put the blower on I thought I would test it out on the drag strip. I don't want to beat it up to bad, and I'm not going to change rear-ends. This is all good information, but I'm just looking for a little better traction on the strip.

I just ordered some Nitto 555R's that will be hear Thursday, I will try to get some more video this weekend.

Thanks again. Have a nice day. Woody