Technically they are probably right, the more weight you can save the faster the car will go. But when dealing with a heavy road car and not a lightweight Formula one car the difference os so negligible that it isn`t worth it.

Something like that is only worth it if you have exhausted all other performance avenues and are just after tiny improvements over big gains already found.
 
This does actually work but not for the figures they are quoting.

General rule of thumb is around 3% gain, you would get a similar gain by removing rotational drag such as the aircon/alternator drive belt.
 
*cough*

The lower weight yields a large reduction in the rotating inertia of the belt train, allowing the engine to accelerate faster. The effect is similar to fitting a lightened flywheel and is particularly noticeable in the lower RPM range before the turbo spools up.
 
This does actually work but not for the figures they are quoting.

General rule of thumb is around 3% gain, you would get a similar gain by removing rotational drag such as the aircon/alternator drive belt.

3%, so still getting on 10bhp then in a tuned lcr...
 
How much do my back seats weigh? if i remove them i should get some BHP too!








Sorry, but without hard evidence i think thats complete arse.
 
How much do my back seats weigh? if i remove them i should get some BHP too!








Sorry, but without hard evidence i think thats complete arse.

Where is your hard evidence to disprove it?

If you remove weight such as your seats, you won't increase your BHP, but you WILL improve your power to weight ratio, I.E Power LOSSES.

By stripping rotational losses, especially from the crank you are decreasing the power losses.

This is why people quote "at the flywheel figures" and "at the wheels or wheel horsepower" because there are losses incurred all the way from the flywheel through to the wheel.
 
Where is your hard evidence to disprove it?

If you remove weight such as your seats, you won't increase your BHP, but you WILL improve your power to weight ratio, I.E Power LOSSES.

By stripping rotational losses, especially from the crank you are decreasing the power losses.

This is why people quote "at the flywheel figures" and "at the wheels or wheel horsepower" because there are losses incurred all the way from the flywheel through to the wheel.

That was my point! Reducing weight won't give you more BHP, it will just give the engine an easier time moving the car as its lighter.
;)
 
All your doing is utilising the power you've already got more efficiently.

For example.....

270bhp has a value of 240whp after transmission losses.

Lighten the inertia of some components..

270bhp now has a value of 245whp.

So yes you can gain power but whp, not bhp:)
 
i can see why it would increase bhp, but realistically only to a very small amount.

The main difference id have thought would be an improvement in responsiveness, however this is also dependant and the flywheel so again the gains would be small.