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Well I finally got back to the drags after not racing for some 12 months. Last time I raced I recorded 14.8 with 117rwkw. I now have 206rwkw so I wawn't sure how I would go. Basically I discuvered a couple of things.

1. TEIN Suspension is NOT good for drags.

2. Low profile tyres are NOT good for drags.

3. Standard clutch is NOT good for drags.

I am not making excuses but these things will have to be improved on before I can expect to see the fruits of my labour.

I believe that my current engine configuration is good for a flat 13 so if I can sort out the other areas I will be happy.

Last night was not just about quick times but I was very interested in sorting out my launches. and as you can see from the times below as I increased the rpm the times came down. However on my final run I made a rather large error, I wasn't interested in reaction time so I let the green light show then consentrated and tried hard to get a good launch, however I moved slightly forward and triggered the timer withou actually launching thus resulting in a time much slower than the run felt. I believe that had I not moved forward that I may have got a very low 13?

Anyway here are my results.

RUN 1

60ft: 2.468

ET: 14.196

KM/H: 157.88

RUN 2

60ft: 2.317

ET: 14.112

KM/H: 165.84

RUN 3

60ft: 2.356

ET: 14.021

KM/H: 164.55

RUN 4

60ft: 2.238

ET: 13.747

KM/H: 162.42

RUN 5

60ft: 2.340

ET: 14.014

KM/H: 167.68

SOMETHING BAD HAPPENED LAST NIGHT AS WELL

After doing a big burnout and then a run my spedo stopped working and hasn't worked since? Also my HICAS light is now on and I appear to not have power steering? HELP

humm its all in the the 60' time 2.3 you need a 1.8 1.9 go halves in some slicks etc ie 15" wheels or 16's a 200 sx with 200 rwkw ran a flat 12 with slicks 15" on 18psi (tyre pressure that is).

stock springs and shockers also on the back and jap r32 drag car listed its rear springs at 3kgs.

you mph tells me low 13's my vh hdt commodore ran 13 .5 @ 105 mph on street p6 perreli's @ 22 psi. and still had traction issues.

as for you hicas stuff check fuses it sound like something came un plugged to me?may be the speedo sensor in the gear box or on the back of the dash.

17's look good but MMMMMMM and every one says why meggala don''t you run 17's well there is your answer.

you have to go back and get a faster time next time around.

meggala

The thing is I don't want to run on slicks as I want to run in TRUE street trim with street tyres just like the jap guys....My plans now are.....

A set of standard rear shocks/springs (for drag only)

15" rims with AZENIS or similar

New clutch (heavy duty)

I have a incar vid of one of my runs where I chase down a V8 Holden ute...Its a bit dark but if you change the brightness/contrast in wmp it looks OK, if anyone is interested I will put it on my site.

cam,

check your speedo sensor at gearbox, mine had some L joint thing that broke and connect the sensor directly onto gearbox without the L joint and its all good.

If you use 16" or 15" with street tyres and low pressure then you might gain tiny bit on the traction side of thing...

and the jap ppl uses nitto or semi slick tyres which is almost as good as slicks anyway.

It was still good to see u and jay51 race together hehe..

I have tein springs and some jap shocks and my car is very very stiff just ask anyone who has been for a ride in it.

the best i have managed to run so far is 14.2 with a 2.1 60ft @ 159km/h that was with around 145rwkw.

This is with 205 compliance tires but with a 50 profile tire and i let the pressure down, i didn't have any wheel spin i took of at 5000-5500rpm and bogged down ;)

All you need is a set of tires with high a profile.

Just for a comparison my mate with a R32 gtst with around 160-170rwkw ran 13.3 on street tires with a 1.8 60 ft and he took off at around 6000rpm.

And the HICAS thing i am pretty sure is a fuse because when i pulled my hicas fuse i lost power stearing and the light came on.

Originally posted by BOOSTMEISTER

The thing is I don't want to run on slicks as I want to run in TRUE street trim with street tyres just like the jap guys....

Spot on Cam! I'm with you :uh-huh:

I'm not interested in what I can run with slicks, no interior trim, no exhaust etc... etc... until I get consistant times in full everyday road trim ;) I want low ET's & high TS's with the only difference from the street being the grip of the surface :burnout:

Keep working on the launch technique Cam, I went from 2.5's down to 2.15 (so far) without changing tyres or reducing the pressures from 38psi. I've heard of LS1 guys getting 1.7 60's on road rubber! :eek:

Thanks for your help guys here is the vid on my run against a V8 holden ute (he had slicks thus his good start)

Sorry its so dark but if you open it in Windows Media Player and go to "VIEW" then "NOW PLAYING TOOLS" then choose "VIDEO SETTINGS" you can make it a bit lighter and up the contrast a bit to see the action.

Cams Vid

(Right Click and Save target As)

I made the vid full screen and basically studied it.. ;)

I noticed close to 8000rpm gear changes.

No traction in first.

I'm not sure but was there a steady loss of traction in second through basically the whole gear and in third when the clutch grabbed in full screen it looks like ones second he's there one he's long gone.

So what size tyre etc are you running?

Good observations Joel

1st. Mass loss of traction, backed off then on the power

2nd. Grip with clutch slip.

3rd. clutch slip (hear the revs) then power and that was it for the V8 ute. He had no pipes on and I could hear it and he was going hard.

Nearly 170km/h over the 1/4 means that the top end isn't too shabby

I have falken ze326 235/40/18 all round

One of the killers on all my runs was the clutch

Guest scooter484

You're on the right track Cam (excuse the pun)!

High profile is the way to go.

Grab yourself some Mickey Thompson ET Street or McCreary Treaded tyres or similar & these will help heaps 'cause they're real soft & the tyre is designed to 'cushion' the take-off shock to maximise traction.

Get the widest that will fit & choose a height so that you are running at approx 10% past peak horsepower rpm across the finish line (miltiply current terminal rpm with existing tyre height & divide by new tyre height to find out new rpm).

I also assume that you're running a LSD or locker as this makes a BIG difference!

There are (greater) gains to be made in the front suspension too - soft springs & 90/10 shocks (a bit extreme for street use but if you can be bothered changing them...) helps the weight transference ie. front of car will lift putting more weight on the rear wheels. (Delete front swaybar will also help).

Traction bars also help - I ran Lakewood ones on my XC & it pulled a full .1 second off it's 0-100 times. As the tyres try to turn forwards - the diff turns backwards. Bars connected to the bottom of the diff housing to a point on the chassis forward of the diff converts the rotational force to a downward one & plants the tyres harder onto the track surface.

Your clutch slippage didn't sound too severe but try either slowing the change down a small bit or getting on the throttle a fraction of a second later to allow the revs to drop to match the new gear & the clutch to bite. These things are too expensive to have to replace regularly! Eliminating slippage will help consistency when racing too.

Have fun!

Scooter.

One of the things I have been wondering about is with semi slicks (AZENIS) etc.....Is there a used by date so to speak, I mean if I use them once a month is this OK or should I use them more regualy (spelling).

I know that tyres go hard after a while without use so I am just wondering??

Does anyone know?

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