EDIT: I'm looking at 182.85hp/tonne :(

OK for my 1200 the numbers are:

183rwkw = 245rwhp

Working off an estimated 20% driveline loss = 294 at the flywheel.

Estimated weight is 900kg. I am yet to have the car on a calibrated weighbridge.

1000/900 = 1.111 x 294 = 326HP/tonne

The good thing about it also is that the more h/p you have to start with the greater the gain after weight loss.

Lets say you fit a super charger to the a15 and its got 180 flywheel h/p and 125rwhp

1000/700=1.428x180= 257.1 h/p per ton

and after weight loss

1000/634.5=1.576x180= 283.68


283.68- 257.1 = 26.58 flywheel h/p per ton


Wow thats double the from the first example....

Ive built it for the under 2lts class, was hoping to be in the top 10 outright. I`ll try with the Turbo A series and get as much weight out as i legally can.

It`ll end up about 300 Kg/T once sorted.

Your def right tho, Cossie55(member on here) runs a SR 20 in the over 2 lts class and makes Big HP! Im looking forward to seeing him up the pointy end.

dude sr20 with 2871 turbo will be eazy around the 350hp mark with stock motor just injectors and niztune :D that give 437.5hp/t

It would be cool if people list their dattos HP/Tonne figures..

Probably too much to ask as most people wouldnt know their car`s weight. but could be interesting.

Just use Datsss`s basic formula.

1000/cars weight x HP= ????

I used the formula to work out how much power i would need to compete with the others on the grid.... Scary!


RX7 950kg/290Hp =305 HP/T
Comm 1350kg/550Hp =407 HP/T

The Datto would need to make 285Hp to be up with the Commodore. Im about 135 short...bugger!

The damaged RB30 180B I recently bought is 1100kgs on the engineers report and thats in full street trim with the bigger brakes and diff required so almost silvia territory but with an extra Litre and potential to drop a fair few kgs of interior.

Makes me think whack a turbo on the side, strip the interior and put in a cage for some stupid amounts of track fun.

Say 150kw for a Vl Turbo motor
thats 182.8hp/ton, mmmmmm yummy!!

Its horses for courses. With controlled class racing like Improved production. Weight reduction is very important.
It makes for higher cornering speeds, later braking, better acceleration off the turns and tires that wont go off as quick during a race.

Faster lap times for longer!

It certainly isnt garbarge for racing!

But for the family car, auto makers add weight to make the car safer. Things like intrusion bars, Air bags and abs.... As i said, horses for courses.

a very mild a15 in a 1200 and theoretically, your 1200's weight is pretty unchanged. i am concerned about weight distribution. if i put an a15 inside a 1200, the weight distribution of the car is pretty much unchanged from the stock. i wouldn't want a powerful car with the weight bias much to the front.


from my memory, a15 is 20 pounds heavier than a12, is it true?

Quote:

if you add an sr20det, gearbox, intercooler & piping, 3" exhaust, upgraded diff & tailshaft to an 800kg car it very quickly becomes a 1000kg car so you may have improved acceleration but your braking and handling is actually worse.

I've always been about 'power' as a solution but more and more I'm appreciating the minimalist approach. Cheaper and better... and if you can also improve power at the same time then that's a double improvement. Eg going from stock A12 to an A15 with a cam and carbs doesn't really do a lot weight-wise (certainly not like an sr, etc) but will give you a good little power increase... and not require massive supporting mods like bigger diff etc.

My "795kg" 120Y is 980kg now that it has a CA18/box/exhaust/cooler. I'm doing some other upgrades at the moment (bigger turbo/manifold/cooler/diff) and wouldn't be surprised if it ended up close to 1100kg. Often these kinda mods make old cars nearly as heavy as new ones... but then you still have old suspension, brakes, etc and limited safety.