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13.4 second 1/4 for your 'stockish' R33. (A how to guide).


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Despite reading this thread, and seeing the excellent results rev has had, I'm still not convinced that the traditional mods aren't the way to go. I think you're just really good at drag racing, rev. That said, it's certainly made me interested in the lightened flywheel. If I was in Perth, it would be good to see what times you could get in my car.

Guest MFX_R33

Jay that just alters the gearing. In some cases that may be quicker and others it would be slower. I know Mario's GTR's gearing, for example, has a very high first gear (I believe it is close to the same ratio as a standard 2nd). Also smaller tyres may make you need one more gearchange before the line which will slow you down.

Jeff.

Jeff,

I understand what your saying, it can make you slower if they are excessivly smaller. But, for say 10% smaller, it'll make a difference without any side effects (other than your speedo being out :) ).

You've got to remember that Mario's beast of a car has been made for the strip, rev's to 10,000, has 1000hp, and he launches at about 8,000rpm and almost every part on the car has been changed for an after market modified part - lucky ba$tard :D .

So in his car there's no use having a standard first gear. He's car also would reach it's absolute maximum speed just after he passes the finish line.

Just as an example, if you take a R33 GTS-t with standard gearbox and stock final ratio, and run it down the 1/4 mile and say you hit 100mph at the end, you'd need to be in 4th gear to make it too 100mph. But if you change your final ratio by 10%, which makes you accelerate faster and you pass the finish line doing 110mph you'd still be in 4th gear, so your not doing any more gear changes than normal, your just accelerating faster.

The absolute top speed of the car will be less, but when most are still limited too 180km/h, I don't think that's an issue :spank:

That's a basic way of looking at it though.

I remember in my old car when I changed from 50 series tyres to 55 in the same size (205's I think), and when I picked it up I thought they had stuffed the car cause it was noticably slower.

Then when I got home and thought about it, it worked out that they were about 8-9% bigger in diameter, so it made sense (plus the fact it didn't have much power to start with :( ).....

Anyway, this is getting totally off topic here..

Guest MFX_R33

Changing the wheels to smaller, will probably make little difference to the E.T. or MPH of your car. Basically the power of your engine is there to overcome the inertia (constant) of your car down the track. If you are going to the extent of playing with the end ratio of the gearing, you would have to look closely to the potential of the car and calculate getting the longest time in the peak power area of you car. With calculation, you caould find that you could just as easily be better off with larger diameter tyres.

Jeff.

Originally posted by MFX_R33

I agree it will improve your acceleration in each gear, but if just running smaller wheels was going to give you a better ET, every drag car would have 5 inch wheels.

Jeff.

See above post :)

Running 5 inch wheels would be cool, slower, but cool :bahaha:

It's totally different when your talking about a drag car that is made for the strip and that's all.

For a road car that see's the track sometimes, dropping the diameter of your tyres a little will be benefical for acceleration.

Like I said, I've tried it and noticed a difference, give it ago yourself and then you'll see what I'm getting at.

Pass the beer nuts...........

Originally posted by riggaP

Can I ask how people launch their rockets? 7000 and dump the clutch? 7000 and ease the clutch out? 4000 ease clutch out? etc

It totally depends on the quality of the tyres you're using! And the road surface of course.

Poor quality &/or worn tyres will spin even @ very low rpm (~2,000rpm) Even good tyres that have "gone off" will be very hard to launch without excessive w/spin.

It's a case of practice makes perfect! Go for a drive & see how YOUR tyres hold up? If the car bogs increase the rev's until it gets away cleanly.

The above info is dependant on the launch method. I prefer to dump the clutch, but slipping the clutch & feeding power on can help if your tyres are shitty.

To give you an idea - I couldn't launch at anything more than 2,000rpm on 255/40/17 Falken ZE502's but now on the same size RE540S's I can take off @ 3,500+rpm.

  • 2 weeks later...
  • 4 weeks later...

i ran a 13.872 @99.56 11.1psi

and its fairly stock, jsut electronic boost controler, cat back, stock airbox, stock turbo, street tyres 255s :P, stock engine, minex vx rom ecu, stock clutch.

jsut a matter of interest, i drop my car at 2500rpm then give it 70-80% throttle. then full throttle after that. i find that makes me run 13's. if i give it all hell i rin 14.5s.

my 60footers are 2.189

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