http://cgi.ebay.co.uk/ws/eBayISAPI....20022939947&rd=1&sspagename=STRK:MEWN:IT&rd=1 This item is advertised as a lightened crankshaft pulley if you can't see the item by clicking the link.... 30 ... reckons it'll give another 10bhp because it only weighs 1.2LBS Anybody bought one before ?? I thought for 30 might as well give it a go and see what happens, havent got round to fitting it yet but should do sometime this week, hopefully quite easy..?? I've got new belts (alternator and PAS) and want to fit a new PAS pump at the same time although it says its a 4 spanner job in the trusty Haynes!!!!!!! D'oh! Words of wisdon greatly received lads...... (and girls!) Cheers, Jon
wouldnt have thought lightened pulley would make much difference. as its small dia it will spin up quite easy un like a flywheel which has a large dia and would require more effort. all down to the leverage effect.
Yeah second that, can't see how it would make any difference to power, and as its not as large as a fly wheel, the reduced weight won't have much of an effect on inertia on a pulley that small
What a croc of sh*t... 10hp from fitting a light weight pulley , do these clowns who sell this junk have any idea how an engine makes power... Save yr money bud, plus as hotgolf say's above.
they do work, they make the engine rev up quicker, much in the same way a lightened flywheel does. but they do not add horsepower. I had a TURN2USA one on my VR6.
It doesn't really matter what size it is tbh, it's weight that the engine has to try and spin. So the less of it there is, the quicker it will spin up.
They certainly wont make anything like the difference a lightened flywheel will make, unless something like a VR6 has a fairly large diameter/heavy pulley ?
it's also an underdrive pulley, so you aren't spinning the alternator and pwer steering pump as fast. i.e. less drag on the crank (theoretically)
Thing is for a cheapy mod its worth a go i guess, seemed worth it cos was doing the power steering pump and belts at the same time... how much do you reckon im looking at for a lightened flywheel or is this just getting into expensive mods i cant really afford ???!
shouldn't be underestimated how much power it takes to spin engine ancillaries - the point to this is the fact that its an under-drive, not really that its made of ali and therefore lighter / easier to spin etc fitted a similar item to my engine this year - in an effort to slow down the ancillaries at 8.5K+ - was concerned that water pump would cavitate at over rev and also that the alternator was spinning too fast (rear lights used to glow on rollers above 8K rpm LOL) - not got too much milage on one yet but if you have a high rev engine, an under drive is a good idea I suspect you could see a slight increase at power ATW figs even on an enegine spinning at normal revs as ancillaries would be turning slower - but probably no increase of power at crank quite what effect the removal of the harmonic balancer will do I dont know but the chap who built my engine says it will be fine and builds euro champ motors, maybe it will have no effect on an engine that has 5K mile rebuilds but may be significant on a more std motor cheers rob
very informative mate, cheers for the advice. Im going to give it a go this week as i said... will let you guys know the results as I get round to fitting / testing
I like the idea of an underdrive pulley if you are making big revs. And if you're that keen on getting every last bhp then I'd look at the kits you can get to cut the alternator out at high revs. It's still spinning, you can't avoid that but the alternator is no longer producing current - which is created in effect by the alternator resisting being turned. Good for 5 to 10bhp apparently and unless you drive everywhere in 1st gear or on the rev limiter it should leave you with a flat battery. barkstar
The underdrive factor may help, as said, in a high rpm application but these gimps that are claiming 10hp are misleading people out of their cash.
It looks like a load of bling to me. Removing harmonic balancers bothers me - without the inside line on harmonics, anyone should be wary. Maybe if an engine has been meticulously component balanced then a builder can argue there's no problem. Personally? No way.
I tend to only trust tried and tested mehtods of gaining power. Messing with harmonics doesnt sound good to me
