95naSTA

iTrader: (10)

Since my clutch was slipping last year at the track I decided to upgrade to a South Bend HD Stage 1 clutch kit.

The good news is I squeeked out a new PB but the bad news is the 1000 mile old South Bend is also slipping after 7xxx rpm shifts.

My clutch was grabbing for the 13.3 run but the tune wasn't 100%. Getting over the stock limiter in 2nd wasn't smooth, then bounced at the top of 3rd. I got that dialed in but by then my clutch started slipping.

Also, a 2.0 60' is kind of b.s. for DRs. Definitely some room left there.


Track prep:
Removed throw rugs, spare, rear seat
MT DRs (255/55/16) aired down 15 psi
Light 15" rear wheels
No air filter
Open exhaust after Y
Rear BCs raised 1" and turned to full stiff
Light 15" rear wheels

Year of Engine: 2008 Altima
Engine Modifications: 3.0l timing, upper and lower oil pans, drilled intake cams/sprockets, 09' Maxima upper intake and (75mm) TB, 4" Intake, Q45 MAF, BPI flow stack, Aeromotive AFPR, Cattman headers, 3" SS exhaust Y-back.
Tuned: Rough tune with EMU, launching at 3500 WOT dump with 2-step
Transmission: AE 5MT VLSD

PBs
60 - 2.044
1/4 - 13.385
mph - 106.32

Slips: (203)


My previous PB was a 13.44 at an identical trap but I never hit 105 and 106 traps before. The major differences are open exhaust, 15s in the rear and the South Bend clutch.

It's a shame that the clutch started to go. I was upping my launch control slowly and I got my lowest 2.0 on my last run, after I let it cool for a half hour. I feel like I could have at least gotten a 1.9. That and with a smooth limiter, should have been 13.1ish.

At the moment I really don't want to do another clutch job and go with slicks. But, if I did and the axles make it, 12.9 or so? I might change my mind. We'll see.

dcpatters

I like that 106 MPH from your PB.

dcpatters

Weather conditions?

95naSTA

iTrader: (10)

It was 75-80 F and 50% humidity. Wind < 5 mph.
The track is 318 ft above sea level.

I just took another closer look at my EMU logs and it looks like my clutch was starting to slip on that 13.3 run..

krazy6

iTrader: (5)

Nice passes!

You might want to experiment with slipping the clutch off the line. I found that works a lot better with drag radials.

Is it spinning or bogging?

95naSTA

iTrader: (10)

Thanks.

When I was slip dumping on DRs, before I had launch control, I was consistently 1-2 tenths slower. Part of that is probably in the touchy converted DBW throttle body. The throttle opens with almost no pedal pressure.

It was bogging a bit but not spinning. I went to a different track maybe a month before and it spun at my last launch setting so I dropped it about 500 rpm or so and was slowly bringing it up during these runs. The reality of it is I probably could have went right back to that old setting and beyond. Hindsight is always 20/20... Another example.. damn, I should have got a stage 2 clutch.. lol

BTW nice #s yourself. I think I remember the thread on that.

cardana24

iTrader: (81)

Good looking times...the two things that stand out to me are the two things you said you don't really want to change. I used to race on drag radials, and I did alright on them when I had a 3.0. Now that I have a 3.5 in my 4th gen I just could not do very much better than street tires (similar 60's to what you have). Slicks really are the way to go, judging by your trap speed we probably make similar power and I was able to do a 1.7x with slicks on some sawblades. Then your clutch slipping, I don't have any experience with southbend. I have always run ACT clutches in my 4th gen. I had just the normal street disc when my car was supercharged 3.0, I assume I was making low 300 hp (I dynoed at 298 with the stock intake manifold, and I went to an 00vi after that), this clutch never slipped at the track on drag radials. Then when I did the 3.5 swap I installed the ACT 6 puck sprung clutch, with the intention of boosting this set up (has not happened yet). This set up also has not slipped on me. I know it's the stuff that you said you did not want to mess with but I am sure you should be able to get into the 12's with tires and a clutch.

Also, just to add how I launch. I normally rev the car up to about 6k rmp and then slip/ride the clutch out until I feel I will not spin. This method has gotten me the best 60' times.