Powerhead Cowl Modifacations for Performance

[olboatman]

Would like to hear about (and pics if ya have them) some mods to cowls done for performance improvement and the theorys for them. Thanks
Gary

[racervboat]

Gary ive cut holes in the front [big ones] vents in the side,took out the rear diffuser no real gains but louvers look cool.Ran my pacecraft with mod motor and big holes in the front against tha Allison [same motor] but he was running a 1975 hood no vents at all and that hood has no cut out in the rear in the grab handle at all and we still ran the same with no bottom to top end difference ?

[FMP]

I opened up the rear top vent at the tilt grab and lower pan vent. Only noticed a difference on the hottest humid days when jetted fat but suspect better air all the tine. Top end ran out better, not a rude but still.

[racervboat]

The two motors I just mentioned one was opened up all over the other no vents in hood at all only air it got was from the pan vent and both motors were jetted the same.No significant improvement at all ?

[FMP]

You run carb covers or boxes?

[racervboat]

no covers

[FMP]

Extra air potential never hurt

[specboatops]

^ until there's a fire...

[FMP]

Sure

[specboatops]

just sayin -

[FMP]

Best to stay in bed that day

[racervboat]

best get some insurance than LOL

[FMP]

Prophylactic?
Any difference between the 85 / 140 pan vent?

[racervboat]

some were cast closed some had the bolt in plastic cover.

[spybot]

I found a few on this Forum from mid 70s till the early 80s Some are from the V8s

I think the general consensus is as racervboat said "no real gains but louvers look cool"