1/4 mile ET's

Hi all,

Having just got my car back from a mapping session, I decided to have a go at RWYB yesterday.

The car is making 570.9hp @18PSI boost.

I ran consistently @13.3s @120mph but my 60ft times were, again, consistent at 2.7s - shocking I know! I know I should realistically be looking for closer to 2s.

Part of me was holding back so as to not destroy my w58, but I really did genuinely struggle for traction.

So my question really is, with a terminal of 120mph, if I could achieve a decent launch, what should I expect my 1/4 mile ET to be?

Apologies if this is vague/there are too many other variables to consider.

Thanks,

Josh

What tires will you be running?

Hi Luc, I was running standard road tyres:

235/40/18 front

255/35/18 rear

my worry is, with drag radials, the additional traction will completely kill my w58.

I would go with 888's at the rear Josh.

Iiv been running the same terminal speeds as you, but ive been using hoosier drag radials. Best time i achieved at santa pod on an un-prepped track is 11.5.

I would go with 888's at the rear Josh.

Can't see why you'd do that. They're for circuit driving and the Supra's handling is rubbish with them only on the back axle.

Hi Luc, I was running standard road tyres:

 

235/40/18 front

255/35/18 rear

 

my worry is, with drag radials, the additional traction will completely kill my w58.

I think your concern is justified! what brand of rear tyres do you have and did you lower the pressures for the runs?

Any vids?

I would go with 888's at the rear Josh.

It wont make any real difference if he changes to R888, they launch just as bad at a track. Even so, 2.7 is quite bad and you could improve on that alot, no idea what you are doing off the line, but it obviously involves using too much power.

Drag racing has less to do with terminal speed and more to do with that 60ft time. If you can get that down to 2.2/2.3 you should see mid to low 12's

It wont make any real difference if he changes to R888, they launch just as bad at a track. Even so, 2.7 is quite bad and you could improve on that alot, no idea what you are doing off the line, but it obviously involves using too much power.

 

Drag racing has less to do with terminal speed and more to do with that 60ft time. If you can get that down to 2.2/2.3 you should see mid to low 12's

I'm assuming due to the W58 box he has, he probably isn't giving it a proper launch needed for a good 60ft time so he dosen't risk damaging it, which is fair enough.

I'm assuming due to the W58 box he has, he probably isn't giving it a proper launch needed for a good 60ft time so he dosen't risk damaging it, which is fair enough.

he wont get a 'hard' launch on street tyres anyway, so id assume when it hooks in 2nd and 3rd is when damage will be done at the track. You are right though. either using to much power or just rolling into the 1/4 mile.

he wont get a 'hard' launch on street tyres anyway, so id assume when it hooks in 2nd and 3rd is when damage will be done at the track. You are right though. either using to much power or just rolling into the 1/4 mile.

I partially agree with you Zach.

255 street tires won't get you proper traction in 2nd gear ... on 888's, you will have traction in 2nd for sure.

I was running street tires with my first single turbo (GT60 turbo with 500+ bhp) ... I was spinning like crazy in 2nd gear. Once semi-slick tires were installed, 2nd gear hooked up perfectly.

I'm assuming due to the W58 box he has, he probably isn't giving it a proper launch needed for a good 60ft time so he dosen't risk damaging it, which is fair enough.

You're quite right. I could, no doubt bring the 60ft down, however, I was encouraging an element of wheelspin to take some of the shock loading from the box.

A 6speed is definitely on the agenda shortly.

With reference tyres, I'm currently running Toyo T1Sports @ 36PSI front, 34 PSI rear, I didn't alter pressures for the track.

I'll get some vids up shortly

34 psi is defo a bit too much Josh.

I run 30.5 psi on the street on the rear.

Dropping the pressure in the rears will increase the tyre`s contact patch with the track.

"35 profile" tyres and "drag racing" don't fit into the same sentence.

Get yourself a pair of stock 16's" shod with 45 profile tyres for the rear.

"35 profile" tyres and "drag racing" don't fit into the same sentence.

 

Get yourself a pair of stock 16's" shod with 45 profile tyres for the rear.

Josh is gonna kill the box rapidly if we continue like that

Josh is gonna kill the box rapidly if we continue like that

Precisely thanks Luc:thumbs:

Please don't think by any means that this thread is me asking advice on how to make my car quicker on the 1/4 mile.

This is merely a thread asking theoretically what would I expect to run if it were possible for me to launch better - ie, if I wasn't trying to preserve my box.

By no means will I be taking up drag racing[emoji16]

Precisely thanks Luc:thumbs:

 

Please don't think by any means that this thread is me asking advice on how to make my car quicker on the 1/4 mile.

 

This is merely a thread asking theoretically what would I expect to run if it were possible for me to launch better - ie, if I wasn't trying to preserve my box.

So many variables it's impossible to tell. Run of the mill street car with decent grip and a good launch with itro 600hp would see easy 12s and maybe even 11s if the conditions were right and the stars aligned. A properly setup car tuned for doing the quarter with everything aligned for putting in a quick run would probably see 10s, low 11s at least.

Quickest BPU Supras are down in the mid 11s, some low 11s in America iirc. I think most are high stall auto's with drag slicks and suspension to match. I do believe there is the odd 6spd in there too right enough. I don't remember any 5spds, I don't know how they lend themselves to the 1/4 mile with regards to the amount of changes required and the length of the gearing.