Curious and nosey.

[jacksdad]

A couple of threads involving juices and gauges has made me nosey. Thinking of what was said on the juices thread about warming up before having fun, I was driving along the M23 this morning at 3,000 rpm, the speedo said 92. (i'll deny it later in court!), is this the same for all of yours ? I drive a 4l hc, just wondering what other specs and states of tune produced.

[shpub]

Speed compared to revs is dependent on the diff and gearbox ratios and the tyre size. Engine tune has nothing to do with it. There is a slight change between the BW and SD1 gearboxes but that is mainly in the lower gears. There is a spreadsheet on my website that calcs this lot for you. Your speedo is a little optimistic as 3000 rpm is about 85 ish. IIRC

Changing the tyre size can give a few percenatge error. Wearing the tread down also increases the error as well.

You can get totally paranoid about this if you want but my advice is not to... Life is too short. Oh and it is extremely expensive to rectify and as I say the accuracy goes as the tyres wear down. The only cure is to coat them in oil so that the friction decreases. However the resulting wheel spin will indicate accurate wheel speed but this will not relate to the car's actual speed and may be many hundred percent out...

Please let's not start a "my car does X mph at XX rpm" list...

Steve
www.tvrbooks.co.uk

[jacksdad]

Thanks Steve, good to know that I wasn't speeding this morning !

[xain]

I had a mate once who's Citroen BX "Leader" used to register 10mph with the engine off.

[mr 8]

Had a 4.0L HC Chimaera, had it up to 176mph on the speedo which was the point that the rev limiter cut in, did this whilst racing an Escort RS turbo which was a H plate, the Escort was on my tail up to 155MPH before it looked like it had no more go go juice, up to the first 120 mph it had no chance, did catch up though after about 2 minutes and kept on my tail at 150mph, the torque seemed to tail of on the Chimaera at 120mph onwards, thats were the 5.0L lump would of been ideal.
For all the coppers reading this, the speed was registered whilst I was dreaming!

[mr 8]

176mph could not of been accurate, dont think the 4.0L lump has it in there, speedo looks like it may be out by a fair bit.

[trefor]

Yeah, an Essie RS Turbo would probably run out of breath around 135mph downhill, wind behind it, with the driver peddling like Fred Flintstone.

T/.

[craigalsop]

quote:
Yeah, an Essie RS Turbo would probably run out of breath around 135mph downhill, wind behind it, with the driver peddling like Fred Flintstone.

T/.

They were very easy to tune, with a rechip easily giving 210BHP. Nice handling car too (for FWD), although with that amount of power they do torquesteer a bit....
I've seen a well tuned Escort RS Turbo (with 3 passengers) out accelerate a 4.2 Cerbie from 80 upwards....
Don't get me wrong, I'm still a TVR fan, I'm just saying don't underestimate RS Turbos

cheers,
Craig

[trefor]

I like them too ... not sure why, but I think XR3is still look the part. Thing is the aerodynamics would prevent much greater VMAX than the std car.

One of the mags recently tried a 'cosser' agains't the new Ashtray Turbo Coupe thing. Both claimed 150mph capability, the mag only got 137 mph (dead heat) from both at Bruntingthorpe. Maybe given long enough they would have gone faster ... That was a newer shape Escort too, apart from the spoiler I assume it has better aerodynamics too.

[Mr 8]

Iv got nothing against any Cossie or RS's, I know how quick they really are when tuned, mate had a 400 + hp cossie with proof from rolloing road and would of left my Chimaera for dead, but at the end of a day it was a Sierra not a TVR