Top speed SHoot out!!!

[zedhead260]

I'm surprised to hear people talk of stability issues.

My car always used to cope with high speed very well (albeit at an indicated 130mph).

No soggy bushes or dampers; uprated ARB's (which I am sure prevent lift); no deep spoiler (just the fibreglass 1 peice repo' of the stock 4 peice); 16" wheel with good tyres, all sat low to the ground - no problemo

 

[240z]

I'm not sure how bad the high stability is, but at bruntingthorpe I got up to an indicated 150, and the car certainly felt pretty light, and I must admit I lost the guts to go any faster before the car did!

 

[ZHead]

Thank you Alan - fantastic motivator to show what can actually be done

It was using an old Japanese tried-and-tested combination of Honda XL500 pistons, L14 con rods and LD28 crank in an N42 block ( 3100cc ). Carbs were 50PHH Mikunis. It used a 3.1:1 ratio diff, and ( crucially it seems ) a transmission with a 1:1 top gear ( ie - no overdrive ). Wheels were 16 inch, with 225-50-16 rear tyres. Report says that they were topping out at 8200rpm in top gear.

That is actually a pretty cost effective way to build a stroker - Honda pistons are readily available and much cheaper than forged ones - goes to show that if you have some degree of expertise and understand what you are doing great things can be achieved without blowing a fortune !

Car was fitted with a modified replica G-nose and a modded version of the Works-type 'B' front spoiler. Rear sported a fabbed aluminium rear spoiler with end plates similar to those used by the later Works Groups 4 & 5 race cars. Not much else it seems.

So there is hope yet Suspension technology has moved on since that magazine article so things should be easier for us than the owner of that car. The G nose must be critical to the aerodynamics, I cannot imagine a normal S30 going quite so fast without a lot of help.

 

[Zed2k]

All we need to do now is to find out who is holding this sort of event this year and gauge interest level I know of 3 Zed owners who would love to see what there cars can do.Bruntingthorpe has some days this year but we need more choice. can anyone find out more?
Rob where do you think is best?

 

[SeanDezart]

I'm deffo. on for this (err hmm, assuming my car is ready) but I will need some notice to organise transport and a day off from here to there !

 

[zedhead260]

Bruntingthorpe has some days this year but we need more choice. can anyone find out more?
Rob where do you think is best?

I don't really know what is best, but if we are going to keep a table of results we need to be sure it's run across the same distance for consistancy.

 

[ZHead]

I was talking to Geoff at Fourways yesterday about his aluminium bodied racer. It takes the straights as fast as his big Aston Martin racer and that reads 170 on the clock so the guesstimate assumption is that his car will touch 170.

When I asked about how this was achieved with such stability, he said they have fitted a venturi section underneath that took an immense amount of trial and error to get right and of course the car is extremely low. The other thing he mentioned was the extended nose section (his is not the same as a G nose), saying that it woul be almost impossible without one.

All this stuff has obviously been gone into at great length before, both in Japan and by people who race S30s. As the data is very obviously all out there (even down to Alan's gearbox ratios, diff ratio, tyre sizes etc) then we should all pretty much be able to get these speeds if we want to.

 

[niagra]

you could do a rolling road shootout day at Raceshack in Tewkesbury. The rolling road is state of the art and the only one in Europe. The great thing is that after signing a disclaimer you get to drive it on the rollers. They weigh your car giving corner weights, do a power run (they only give you at the wheels figures and it's a lot lower than you think!!), then you do a 0-60 run, a top speed run and a standing quarter mile run.

It's a great day out but a bit scary the first time you get up there as you're driving your car 4 foot above the ground at over 100mph and not moving anywhere!!. I went along with my Sunbeam Lotus and 7 other SL's including a genuine works car. Absolutely fantastic watching a works car rev up to 8000, sparks coming off the clutch and reaching it's max of 96mph way before the quarter mile is up.

Dario

 

[Russ]

And we could make some very good shootout vids

 

[niagra]

yup, our day was for an article in Practical Performance Car and as part of the package a dvd of the day is included

Dario

 

[zedhead260]

As the data is very obviously all out there (even down to Alan's gearbox ratios, diff ratio, tyre sizes etc) then we should all pretty much be able to get these speeds if we want to.

Yes, providing we can find a long enough straight............or something oval ?

 

[SeanDezart]

I've seen 'Geoffs' racer and seen how it had an amazing amount of trouble getting off the line, I don't know what ratios were being used but it would suggest a high top end !