my mk 5 van has an s2 engine fitted and its been on the dyno only doing 120bhp at the wheels at 1 bar boost
the guy said its running rich at top end
all the boost pipes have been replaced so theres no air leaks and no dv filled
so what needs adjusting? the guy says the power is about normal it was rapid when i had it but it seems to bog down on boost

 

What other mods are done to the car

120@ the wheels will be roughly 145@ the flywheel, it doesnt seem right if the car is running 15PSI boost

 

Take it to a local tuner and have the test the system.

 

120 is 141 at crank

 

you cant say that is a definate figure! my old engine was 118 at the wheels and 156 at the crank. there's usually a 30-40 drop from crank to wheels,i've seen one drop over 50 on the roller's

 

it works as a percentage, for example, most lancer evos lose 24%, so a 100bhp evo would make 74 at the whells (losing 24bhp, where as a 1000 bhp would make 740bhp @the wheels, loosing 240bhp

 

Front wheel drive Wheel bhp devide by .85 = crank bhp
NO OTHER FORMULA

30/40 loss?

Must be the most inefficient gear box invented

The NEW QUAIFE BALDRICK perhaps.

either that of someone's rewritten Mr Newtons rule book.

 

Also me old china 118 at Wheels= 139 at crank

Where the 156 came from the lord alone knows

Even a four wheel drive (as zippy states above) doesn't loose over
25 % of it's power through the drive train.

And again unless your Rolling road operator has managed to rewrite the laws
of physics/something you and I know he hasn't, I think he may
have been fibbing slightly.

REmember kiddies the machine measures wheel horse power, nothing else.
The crank power comes from whatever fanciful figure the operator
or software he uses cares to calculate

.

 

cheers all, wheel bhp is all that important to me,
the problem is that when i got the car it was dynod @ 176 bhp @ wheels and it was rapid
but after the valve spring broke and and fixed and now its had a nother engine fitted its been holding back, thats why i took it to aldons dyno in dudley to get them to see whats wrong,
everythig has been changed apart from the wireing
any how im sure ill get it sorted oneday

 

well they're brand new rather expensive 4wd rolling road is telling everyone lie's then!!!