Scooterotica

I have heard about your good work on RBs mick . Ive got some figures for you here lads, Panal off, 19.86 BHP, 15.7 ftlbs, panal on, 19.32 BHP, 14.7 ftlbs of tourqe. Can somone with more knowledge than me explane why such a large drop in the tourqe compared to BHP, he rearly needs to hole his panal. And even if the dyno was reading 10% too high, these figures still take some swollowing ,

Doesn't the Muggy V4 have a piston ported rear boost port?
Perhaps this is the key here with the extra transfer area. Seems that the ratio of transfer area per bore capacity must be a lot higher.

Chris, your right is does have a window cut into the piston to match the boost port in the barral, and a large finger,d inlet. There is a downside though, if these new small block muggys can make this much power reguarly, then you may have to price in a uprated crank and clutch, its never win win.

eibargum wrote:I have heard about your good work on RBs mick . Ive got some figures for you here lads, Panal off, 19.86 BHP, 15.7 ftlbs, panal on, 19.32 BHP, 14.7 ftlbs of tourqe. Can somone with more knowledge than me explane why such a large drop in the tourqe compared to BHP, he rearly needs to hole his panal. And even if the dyno was reading 10% too high, these figures still take some swollowing ,

Hi
There are a few factors to look at with this i.e with the panals on 1, heat build up from the engine the carb is sucking in hot air that is building up in the engine compartment this will efect performance especaly a dyno room where there is no natural surculation of cool air. 2, if the mouth of the carb is facing the panal and there is only a small gap between the 2 this can cause you problems as you get a resonance wave out of the carb that will hit the panal and bounce back into the carb and upseys the performance the same ting hapens with those cone type filters that have a hard back, the only way to make them work rite is to space them away from the carb, running without the panal the carb is fresh air all the time and there is no heat build up = more power

I hope that is the answer that you were looking for

Cheers
Mick