what would the top speed be with a cbr1000 engine and a sierra diif be about.
adam

More info needed i.e diff ratio and wheel size
theres a spreadsheet kicking around somewhere that works out the speed for you.

Al.





Originally posted by oadamo
what would the top speed be with a cbr1000 engine and a sierra diif be about.
adam

Look up Kissy's threads on this.

CBR1000 doesn't do at all well on top speed.

What max revs?
What wheel and tyre size?
What diff ratio? for there are 4 available
What 6th gear ratio?
What BHP & Torque?

Two replys while i was typing, must try harder.

Approx top speeds on 205/50/15

3.6 = 110 ish
3.38 = 125 in a 7. 135 in a Fury
3.14 = 135 to 140 if you have the power to drive through the poxy aerodynamics

It depends on all the above factors.....
but it's worth remembering that you gain top speed at the expense of acceleration and that a Se7en hits an aerodynamic brick wall at speeds around 120ish.
So even if your car is geared (taking into account the diff, tyres etc) to go to 160mph it's not going to have the oomph to get there.
Best option is to get a speed calculator, type in all the above variables and then play around until you get a combination you like.
Personally I chose my diff, tyres etc so that my car red-lines in 5th @ 120mph and that's fine with me. Accelerates like sh1t off a shovel and 120mph is more than enough even on most tracks

Surely its not about how fast you go , more about how you get there

changing my gearing from 125 to 105 at 10k rpm knocked nearly 2.5 seconds off my 1/4 mile time . gearing much over 10mph per 1000rpm needs a lot more power than an old cbr engine to pull properly

also do you mean the old school cbr 1000 like in your archive or a new 'blade' one

you'll need breathing apparatus at that speed

Not a bike engine in mine, but when I get the 2.28 BMW diff in Deimos, it'll have a theoretical top speed of 196

ATB

Simon

Don't forget in overly simplistic terms

power:weight is about acceleration
BHP + aerodynamics is about top speed

If you're going for a light weight car and modest BHP (ie a good power:weight due to low weight) you're never going to go stratospheric. Meanwhile an aerodynamic but heavy car with tons of power will accelerate slowly but have a good top end speed.....

send me your email address by U2U and I'll send you a copy of the PPC Gear Chart. It is a spreadsheet you plug all the gear ratios etc into and will give you in gear speeds and (theoretical) v-max!

There are some square laws applicable here that will ensure that even if you supercharge your 1585cc Hayabusa, your 7 brick simply isn't going to go a helluva lot quicker than 130mph...... gear accordingly!

Didnt realise how the aerodynamics in these cars are so bad. Really have to have a good think about diff ratio.

Anyone here driven at Knockhill? I'm wondering if 120mph means that you would be banging off the rev limiter in top gear going over the start/finish straight?

Suppose that depends on how much power you have also

download the spreadsheet from my avatar link below, gives you all the ratios and diff choices and calculates max speed in each gear.

i had 156mph on gps with turbo bird lump, anyone who says a 7 will struggle past 120mph does not have a clue.

Re Knockhill.........105 before duffus in 150bhp+ blade indy ditto going into hairpin