Hi all, I currently have a 3.5 litre with ported heads on standard
vitesse valves, a road/competition cam and a Holley 390 on a ported
Offenhauser manifold. This lot only gives about 210HP, peaking
at 6000rpm. Looking at the power curve the engine is pretty efficient
up to 4500rpm then starts to drop off. The unit has been dynoed and set
up. Since the Rover heads are known to be so restrictive my question
concerns the worth of having big valves fitted to the heads. Would this
increase the power much at the top end ? I don't see why I should have
to make the move to a large capacity engine at the same time, after all,
an honest 250-260HP from 3.5 litres should be attainable at 6000rpm.
I realise that mid-range may suffer a bit but this doesn't bother me as
the car weighs less than 1500lbs. I imagine I would move to a 465cfm
carb at the same time and possibly fit a Huffaker intake although this
might be overkill for a 6000rpm motor.
Any thoughts ? Has anyone tried this sort of combo before ? If I could
get 250HP I would be fairly happy and the heads would then work fine with
a bigger motor in the future at no further expense.
Ian
--
"Most people are other people. Their thoughts are someone else's opinions,
their lives a mimicry, their passions a quotation." - Oscar Wilde
Ian Crocker ian@btcase.bt.co.uk http://www.geocities.com/MotorCity/9190/
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