Predicting performance - speed + acceleration (0-60)

[eSteve]

Opps..

missed out Caterham link last bit of post should read:


Data obtained from:

http://www.caterham.co.uk/assets/html/showroom.html

Clicking on each car takes you to its specification.

eSteve

p.s. the curve fitted to the max speeed data is probably a tad inaccurate for bhps under 100.


eSteve

[slimtater]

I have seen something somewhere that takes in to account other factors and diff ratio - this will explain why my 125bhp manages about 4.5secs.

[Davey]

In my humble opinion torque is what gives you acceleration not BHP. BHP is simply a mathematical figure arrived at by multiplying the torque by the RPM then dividing by a constant. It is therefore pretty meaningless in terms of acceleration. High BHP figures are often achieved by using high revs, great for a circuit car but not much use on the public highways.

My aim is a fat torque curve with a smooth, progressive delivery across the rev range which is why I'm chucking a V6 24 valve Cossie lump in mine. I recently saw a BHP/Torque graph for a similar engine that gave over 180 ft/lbs of torque at just 2000 rpm and just climbed in a near straight line from there to the 5800 rpm rev limit, max BHP at 5800 was a healthy 233BHP.

Could be fun .

D.

[spud69]

Try this one Steve:

http://www.letstorquebhp.com/calculator.asp

I have found it pretty good, tis based on historical data. My car is 170 bhp and 540kg, program says 0 to 60 in 3.9s and my car did it in 4.1s with crappy road tyres on. Will be putting Toyos on soon and will certainly get down to 3.9s or better..... Standard tyres seriously let the time down as having to control all power of the engine balanced through the clutch and throttle to get optimum traction. Happy with the sierra standard dif though, once you put loads of power through it you get equal drive to both wheels leaving parallel black lines all the way down the road (private of course).

AndyH

[Enoch]

Interesting. i guess there comes a point where traction is at least as important as outright power. I will only have 125 brake to start with but I do like what Davey's doing with that Cossie lump. That has to be one of the cheapest ways to big power ever. If mine does the 0-60 dash in 6 I will be a very happy bunny.
Enoch

[Bonzo]

If I get a sub 6 second 0-60 .... I might very well soil myself

100bhp is more than enough in a 7 anymore is just pub talk....

[spud69]

Originally Posted by fabbyglass

100bhp is more than enough in a 7 anymore is just pub talk....

Oh no no no, you do need more. But yes i would say that 180bhp is the limit. Anything else is wasted and takes the playful fun out of the drive unless you are out and out track.......