So I went to the drag tonight and....

[cobrAA]

..I was really unhappy with my times! GRRRRR!!

Best one I did is 12 flat, I mean 12.00! ( How lucky I am haha!). Last year, I used to do 11.8 and my car had stalling issue ( bad bov) so my rpm wasnt steady in between gear and my launch was at 2k.

This year, I'm making 20 whp more but also great 40 lbs of torque. I refitted oem bov, tranny has been ''rebuilt''. so I had high hope to do AT LEAST 11.5 but my average was 12.3

The clutch: I used to have a 6 puck clutch and it couldn't hold the torque and was slipping. Honestly, I'm scared my TS2B isn't holding the extra 40 lbs of torque I got I mean, from 2 to 3 and 3 to 4, I'm not sure if I'm just a stupid noob but I felt like the clutch was ''slightly'' slipping. It grapped but its like only the rpm kept moving and the car wasnt. Also when I got my tranny rebuilt, they told me the disc wasnt top shape but when I told them the waiting time and cost of a rebuilt kit they said : ''ooohhh that much!? umm okay well we'll just resurface your flywheel then sir!''

Launch: I think I was always around 6k. Is that too high of a launch?

Where should I shift : I think this was my main error, I was shifting around 7-8k, I think most twin GTRs make most of his power around 6k, so should I have shifted at 6k instead of 8k ?

Traction: II have a torque split controller, Am I wrong to put it in 10 ( highest ratio) in order to get more traction from the front for least spinning or should I keep it at 5 or maybe 0 (oem spec) ?

My tires ( sumitomo htr III) are probably not the best, most sticky tires out there but I think they are still a good performance tire and should be the one to blame.

At 12 flat, I was still the fastest car that night, but I was expecting better, please help :P

[RABBIT]

So you ran different tyres last year?

[bourquetc]

What power do u have at the wheels? I was launching at 6500 and i did a few at 7200rpm with launch controll. And i was shifting at 7500-8000rpm u dnt want to shift lower then that otherwise you rpm drops down to much in the next gear.

[Voodoo_ChildR32]

Flywheel will most certainly be part of the slipping issue. Our car's flywheels are non serviceable as per the FSM. Especially with a hydraulic clutch, once you machine it you decrease it's thickness causing the clutch disc to have to travel further to make full contact with the flywheel. It's been a rule of thumb at every automotive shop I've worked for.


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[gtrjon]

no one will be able to tell you anything without your trap speed! also if your clutch is slipping you will know it. it wont slip a little bit at the drag strip it will slip or it wont. post up a video and your trap speed so we can help

[bobbo]

I strongly suggest leaving your TSC at "0". IMO you'll get the benefits of the ATESSA for the launch but not as much drive line loss for the rest of the run.

[allwheeldrifter]

Never launch under 6500, always shift as high as possible, im not sure but if u put max front torque, maybe it steals a bit a WHP. And last night was pretty humide, and that does a HUGE difference! Im waiting to go late august on a nice cool night, hopping for very low 11

[Phastwon]

I ran 11.87 at 119MPH only 2 weeks ago. I was launching at 6500RPM, and shifting at 8500RPM. I have an upgraded head though and larger turbo's. If you are running the same you should be making good power all the way to redline, you should use it all.

The only reason to shift is either A) you are at redline, or B) at the RPM in the next gear you would be making more torque than at the RPM in your current gear. You should leave the Torque split with a bunch of rearward bias, as the weight is going to transfer to the rear at launch, so you want to use the extra traction.

I run an OS Giken TS2CD clutch and had no slipping issues. It was actually really good off the line, as it had a nice soft engagement under high power and load. I was cutting low 1.7 60foot times all night on Toyo R1R street rubber.

I would post the timeslip so we can analyze a bit better.

[NismoS-tune]

Ah if you need a better clutch I have a twin Carbonetic clutch, Freshly rebuilt, up for grabs. good for 900ps.

[Skym]

More rear bias will give higher trapspeed, et. More front wheel bias will give stability while sacrificing trapspeed, et.

One way to get better 1/4 mile times is to dial in the rear wheel alignment with adjustable upper arms. Skylines tend to run too much camber on rear when squatting.

Another trick to get better et is to hold onto gear over the line (finish line) and keep engine at peak hp (as mentioned above), don't shift up. One R32 GTR I know of went from low 11sec to high 10sec while holding onto gear over the line. He was consistantly running low 11 sec 1/4 mile.

With launching, can load up against handbrake or rev, clutch dump. Make sure you have drivetrain locked up or could do some damage.

Also ride height and good front, rear LSD's (setup for drag racing).

[cobrAA]

Flywheel will most certainly be part of the slipping issue. Our car's flywheels are non serviceable as per the FSM. Especially with a hydraulic clutch, once you machine it you decrease it's thickness causing the clutch disc to have to travel further to make full contact with the flywheel. It's been a rule of thumb at every automotive shop I've worked for.


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I have the os giken lightened flywheel tho. Suck if it's true

no one will be able to tell you anything without your trap speed! also if your clutch is slipping you will know it. it wont slip a little bit at the drag strip it will slip or it wont. post up a video and your trap speed so we can help

no video available but I will scan some time slip.

I strongly suggest leaving your TSC at "0". IMO you'll get the benefits of the ATESSA for the launch but not as much drive line loss for the rest of the run.

I should thought about that last night, next time I will try.

Ah if you need a better clutch I have a twin Carbonetic clutch, Freshly rebuilt, up for grabs. good for 900ps.

Frank, an you please stop spamming every thread in this forum with your for sale item? If they don't sell its propably because you ask too much so consider lowering your price instead of spamming each single threads.

thank you

More rear bias will give higher trapspeed, et. More front wheel bias will give stability while sacrificing trapspeed, et.

One way to get better 1/4 mile times is to dial in the rear wheel alignment with adjustable upper arms. Skylines tend to run too much camber on rear when squatting.

Another trick to get better et is to hold onto gear over the line (finish line) and keep engine at peak hp (as mentioned above), don't shift up. One R32 GTR I know of went from low 11sec to high 10sec while holding onto gear over the line. He was consistantly running low 11 sec 1/4 mile.

With launching, can load up against handbrake or rev, clutch dump. Make sure you have drivetrain locked up or could do some damage.

Also ride height and good front, rear LSD's (setup for drag racing).

I have LSD stock. I will look into it.

[cobrAA]

So you ran different tires last year?

Yeah, I had general exclaim UHP before.

What power do u have at the wheels? I was launching at 6500 and i did a few at 7200rpm with launch controll. And i was shifting at 7500-8000rpm u dnt want to shift lower then that otherwise you rpm drops down to much in the next gear.

Well on the drag, I didn't notice it but on my way back to the line, I noticed that when I was shifting at 3k to my 2nd gear, the rpm would drop to 2.3k and then once the full gear change has been made the rpm would re-drop to 2k, I don,t remember my car doing this before.

Never launch under 6500, always shift as high as possible, im not sure but if u put max front torque, maybe it steals a bit a WHP. And last night was pretty humide, and that does a HUGE difference! Im waiting to go late august on a nice cool night, hopping for very low 11

True, it was humid but almost cold for summer, like 23-24.

[cobrAA]

My best MPH that night:

[Skym]

I have LSD stock. I will look into it.

Some say stock front diffhead is more like 1 wheel drive, so 3 wheel drive.

Look at OSGiken front and rear LSD's -

http://www.osgiken.net/products.php?product=lsd

[allwheeldrifter]

My best MPH that night:

Wen u did ur faster time... Were u at the same track? Kuz i gained 0.4sec at icar compared to napierreville