Would you guys say this is quick?

Cryfreeman said:
what sort of 1/4's are people doing in these anyways?
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Hi m8

Guys running similar setups but with drag tyres. So say a 15/16" wheel on the back with huge rubbers on the rear. Are hitting 60mph in 2.9-3.1s and doing the 1/4 in 10.8s - 11.2s thats guys with around the 500BHP area at the crank. With terminals closing on 130mph. Basically same mods as mine, better more aggressive tune though and drag tyres. :)

Those on street tyres and larger wheels are ranging from 11.4 - 12.2s dependent on driver and shifting technique etc. Terminals vary from 115-124mph. (Again pretty identical setup too mine)

The guys who are tuning my car have theirs running around 640BHP on the stock engine internals, its also an AUTO with drag slicks. They just ran a 10.2s 1/4 with 134mph terminal on the West Coast. Their best result yet!! :D

They are aiming for 9.9s area with the engine still on stock internals and then its time for some serious modifications. I am running my Saleen Supercharger at 7.5psi whereas these guys are at approx 12psi I believe. :D
 
Vertigo1 said:
Erm, that doesn't work.

If 2000rpm in 3rd equates to 30mph then 6500rpm is 97.5mph.
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I've just looked at the spreadsheet and inputting my tyre/wheel size along with manual 3.55 gears means that 2000rpm is actually 34mph and 6500rpm is 119mph. So its a little bit out which no doubt SKU's the figures a bit, probably puts it in the 11s area. :)

Still I don't know how you only get 97.5mph at 6500rpm though? Even with 4:10 gears installed which are shorter 6500rpm still results in 102mph in 3rd at 6500rpm. :)

For 6500rpm to be 97.5mph in my car I'd need to have 4.30 gears installed which are incredibly short, yes it would accelerate a lot more quicker but it would use tons more fuel and a supercharged car does not particulary need such short gearing.

P.S. If I had STD wheel and tyre sizes (235/45/17) then my top speed in 3rd would reduce to 104mph with my gears, however as my car has 275/40/20 wheels/tyres it greatly increases top-end in each gear.

Then there is the fact that so many guys running these in 1/4 in the US are getting terminals in the 115mph area and are still in 3rd.
 
I'm confused now :)

Granted I know squat about cars but surely, in any given gear, the ratio of engine speed to vehicle speed is fixed?

Thus if, in 3rd, 2000rpm equated to 30mph then that's 15mph per 1000 engine rpm, so 6500rpm = 6.5 x 15 = 97.5mph?

Or am I doing something very stupid here?
 
Vertigo1 said:
I'm confused now :)

Granted I know squat about cars but surely, in any given gear, the ratio of engine speed to vehicle speed is fixed?

Thus if, in 3rd, 2000rpm equated to 30mph then that's 15mph per 1000 engine rpm, so 6500rpm = 6.5 x 15 = 97.5mph?

Or am I doing something very stupid here?
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Your maths makes perfect logic m8. :)

Though maybe tyre/wheel size combo's SKU this and therefor make this logic no longer possible?

Give me your email addy if you wish and I can send you the spreadsheet that works it all out for the 2005 upwards Mustang. :)

Can't deny the evidence and fact that proper measuring equipment has been used and these cars certainly do peak at 118ish mph in 3rd when running a similar wheel/tyre size combo to myself as long as 3.55 gears are used.
 
Email's in trust if you want to send them through. Be interested to read but I could well not understand a single word of it :D

EDIT: Actually, now I think about it, if 118mph equated to 6500rpm then that's 18mph per 1000rpm so that'd be 36mph at 2000rpm which makes more sense. There's probably also a bit of speedo error to take into account.
 
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Vertigo1 said:
Email's in trust if you want to send them through. Be interested to read but I could well not understand a single word of it :D
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Hi m8

Just worked it all out and your logic is correct. The spreadsheet is full of formulas etc. so I had it on the wrong column.

2000rpm = 36.39mph

So divide 36.39mph by 4 and you get 9.09mph which gives you your per 500rpm amount.

So times 36.39mph by three gives you 109.19mph at 6000rpm, so add your 9.09mph on for the extra 500rpm gives you 118.28mph in 3rd at 6500rpm.

So your logic is correct, its my fault for reading from the wrong places.

So the correct figure should be 36.39mph - 118.28mph is what is actually taking 10.48s. :) So that still fast? Certainly feels it!!

So a real 30-120mph will be approx a second more and a bit maybe. Going through the gears will probably shave 2-3s off that. :)

P.S. Just seen your reply. ;)
 
Well tonight was the second time I have been out in the beast since being supercharged. What a machine is all I can say!

Trying to hold a laptop while being pushed back in your seat and pressing buttons was rather fun. :D

The acceleration of this thing seems to be unstoppable - it just keeps going and going and going with no drop in pace. At the same speed, the Mustang feels like you're going a lot quicker than you would in mine.

Going through Meir Tunnel was rather fun. :D
 
Simon said:
Why are you asking a car forum if your car is fast ? :confused:
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Well why not?

Simple really I had nothing else to compare it against and by posting on here I now have several comparisons from what other cars have done. :)

Also have found out about a 30-130mph event which I would certainly like to attend so for me the post has been worthwhile.

This is afterall a forum, one about motors where we discuss motors whether they be our own or not.
 
cloudy said:
Didn't mean anything by it!

It's just I now count over ten mustang threads gibbo's started, he must really love it :D

James
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Only 10?

I've had it now 9 months, thats not bad a thread per month. :)

Wonder how many post Fox has made about Mondeo's, BMW's and Goodyear F1's? ;)
A lot more than 10 I tell ya! :p
 
cloudy said:
lol, you are probably right actually!


so what's this 30-130mph event all about? is it without shifting?


J
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Hi there

From what Cryfreeman was saying you go through your gears to try and do it in the shortest time possible. Something that I'd certainly like to try and they use proper timing equipment that is accurate. :)
 
merlin said:
I enjoy reading about the Mustang.
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Hi m8

As I liked reading about your Honda when you were just as involved with modding that car like I am with the Mustang. :)

Even enjoying reading your threads on the BMW and look forward to your feedback on the remap if you get it done.
 
Apologies if this has already been mentioned, but I recently read in Autocar that when they test the in-gear acceleration (the 30-50, 50-70 etc times) they do it with the car already accelerating.
In other words, they don't hold it at a steady 30 mph then floor it. I was really shocked to read this, as I was always under the impression these figures were to simulate an overtaking maneuver where you would be at a steady speed.
 
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