more power 77

WORNOUT

Member
my 77 needs head work, wondering if it is worthwhile to port and polish at same time? would like a bit more power Thanks
 
It was 40 years ago, but the guy I worked for as a kid got a piston + sleeve kit from the Oliver dealer - I think it increased the bore from 3-1/2 to 3-5/8 or 3-3/4. He said he "superized" it.
I loved that tractor - I'm still trying to find it
Pete
 
I never did the 550 valves but did several with Super 77 valves The Super valves were cheaper and the tractors were being used as chore tractors. I did need to shorten the rocker arm supports ( super's have shorter supports).
 
Pete, Do you know Vandeworker's? They live on Lake Road and may have a 77. Jeff said his dads owned his 77 for at least 30 years. Jeff sold a 77 to Cooperstown Bat Co. narrow front a few years ago.
 
I've dynoed a lot of engines over the years and have found that porting and polishing starts to work after 4000 rpm. If you're going beyond 4k, go for it, but also make sure you have them flowed to make sure you're going in the right direction. A tuned exhaust needs to complement the intake mods.

For good low rpm (1500 - 3200) power, small ports increase velocity and the rough unpolished surface mixes the fuel/air really nice. It certainly does't hurt to due some port matching which ever your direction heads.

It has been a while since I've looked at a 77 head and don't know if one of the biggest power power boosts old Chevy guys used will work.

See the link below.
Lump the head.
 

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