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This is going to be great.

I reckon its going to be the first, and last time I ever launch my M5 from a standstill, HARD.

Any tips ??
 

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uprate the clutch??
Its probably not worth it for the one day out, vs my usual routine day in day out in London traffic.

But if my new stock clutch does ever go limp, I will be doing an upgraded one. 9000 Miles of SC driving and it still seems fine.
I might get the rear diff mounting strengthened up.

Sy, what final drive ratio is your Quaiffe running, is it 3.15 or not ? How many MPH per 1000 RPM in 6th gear now ? Stock is just under 30 mph per 1000 rpm or 89mph at 3000 rpm, I think.
 

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Kumaran, there is a video of a dinan s2? with the lower ratio final drive - absolutely demolishes a stock car. Sy should be pretty quick through the 1/4 mile.. hence my tounge in cheek request to swap diffs before lining up on the track - i figure that might make things even, but with boost and a lower final drive ratio he is holding all the cards!
 

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Kumaran, there is a video of a dinan s2? with the lower ratio final drive - absolutely demolishes a stock car. Sy should be pretty quick through the 1/4 mile.. hence my tounge in cheek request to swap diffs before lining up on the track - i figure that might make things even, but with boost and a lower final drive ratio he is holding all the cards!
Yeah I think I have seen that one.

It would be interesting if the more agressive diff, had to necessitate an extra gear change on the quarter mile run....I know in the stock car that 4th is revved out at 125 ish, iirc, so the lower ratio'd diff might need to have get into 5th by the time it crosses the line ??

I wonder. Let me check Clemster's (Adam) videos, I think he has a 3.45 ?
 

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Discussion Starter · #8 ·
It's a stock drive ratio-3k for getting something like that, I'm not competitive drag racing so not worth it IMO on a sc'd car, but a NA car?-def-it's one smart mod which narrows the gap between sc'd and NA.
Also there's a significant difference between by front-rear wheel tyre widths (255 and 285) some thing I didn't realise which also significantly affects traction,and the dsc which I need to rectify when funds are available. I'd ordered these in my enthusiasm without proper research. The 3.45 diff optimises the 0-60 and 60 ft times which have a significant impact on your 1/4 mile times. Technique is also key.
 

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Do you know the specs of your Diff ?? It will be interesting to see how it handles the torque coming out of the corners !!
 

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Discussion Starter · #12 ·
You'll only see the diference between diffs at the limits, I think the launch may be different between different diffs but there are lots of other factors-driver, tyre size and spec etc etc.
If I'm not happy with traction despite optimising tyres handling and most importantly my skills, I will go drexxler. As wkd said- santa pod is a straight line...
Stilll you may sEe differences, final drive ratio will be a more significant factor I think along with tyre choice and driver technique as well as the conditions.
 

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I used to go to Santa Pod quite a bit when i was younger but not been for about 5 yrs. Last run i did was 111mph terminal 13.3 sec in my old 3 door Cosworth,was running around 350bhp. If anyone who went to the Kent meet at the Woodmans last year remembers a friend of mine popped up there in a red Volvo 854 R,terminal on that was 119mph & in 12's(its far from standard). Also another friend who lives down the road has an old A reg XR4i with Cossie running gear he's owned it for about 10yrs & is always improving it. Last time i was at the Pod with him his fastest terminal was 116mph at 12.9 running about 380bhp, its now been rolling roaded at just over 480bhp with different block,T38 turbo & setup by Tony Mannock of Turbosystems.

What terminals do you think you supercharged guys will hit over the quarter ?

Simon.
 

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With 800 HP I would want to hit 130 ;)
 
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