Jump to content
SAU Community

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


Recommended Posts

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

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Look for broken wire or bad connector at the motor. Might not be it, but is worth starting there, as it is easy.
    • Hi everyone, I’m having an issue with my R32 GT-R. Sometimes, when the car goes over a bump or experiences some vibration, the 4WD warning light comes on the dashboard. When I check the code from the control unit in the trunk, it shows Code 19 – ETS Motor. However, everything seems to be working fine — if I turn off the engine and restart the car, the light goes away and everything functions normally. Has anyone experienced this before? Where should I start troubleshooting this issue? Thanks in advance!
    • I'm back from the dyno - again! I went looking for someone who knew LS's and had a roller dyno, to see how it shaped up compared to everything else and confirm the powerband really is peaking where Mr Mamo says it should. TLDR: The dyno result I got this time definitely had the shape of how it feels on the road and finally 'makes sense'. Also we had a bit more time to play with timing on the dyno, it turns out the common practice in LS is to lower the timing around peak torque and restore it to max after. So given a car was on the dyno and mostly dialled in already, it was time for tweaking. Luis at APS is definitely knowledgable when it came to this and had overlays ready to go and was happy to share. If you map out your cylinder airmass you start seeing graphs that look a LOT like the engine's torque curve. The good thing also is if you map out your timing curve when you're avoiding knock... this curve very much looks like the inverse of the airmass curve. The result? Well it's another 10.7kw/14hp kw from where I drove it in at. Pretty much everywhere, too. As to how much this car actually makes in Hub Dyno numbers, American Dyno numbers, or Mainline dyno numbers, I say I don't know and it's gone up ~25kw since I started tinkering lol. It IS interesting how the shorter ratio gears I have aren't scaled right on this dyno - 6840RPM is 199KMH, not 175KMH. I have also seen other printouts here with cars with less mods at much higher "kmh" for their RPM due Commodores having 3.45's or longer (!) rear diff ratios maxing out 4th gear which is the 1:1 gear on the T56. Does this matter? No, not really. The real answer is go to the strip and see what it traps, but: I guess I should have gone last Sunday...
    • 310mm rotors will be avilable from Australia, Japan, and probably a few other places. Nothing for the front can be put on the back.
    • The filter only filters down to a specific size. Add to that, the filter is AFTER the pump. So it means everything starts breaking your pump even if its being filtered out.
×
×
  • Create New...