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cosmo
07-27-2005, 08:43 AM
I was thinking of doing some head work and oversizing my valves. I dont know what size they are right now but would like some feed back from you guys. Have any of you done it, does it make a difference with the car?


63' Lark, 170 OHV.

JDP
07-27-2005, 10:37 AM
I don't pretend tp be a OHV six expert, but I do know the heads tend to crack around the valve seats and I think bigger valves would just make it worse.

Studebaker On The Net http://stude.com
64 R2 4 speed Challenger (Plain Wrapper)
63 R2 4 speed GT Hawk

Mike Van Veghten
07-27-2005, 01:55 PM
In general....yes, bigger valves, a good valve grind and some carefull porting does up the power and driveability. I do porting on the side and can say it all works in a positive way when done right.

But..on one hand OHV six's can be made to run very well with the normal power tricks that works on most any engine, cam, compression ratio, head porting, boring, etc...
On the other hand...as JDP says, all of the above tends to make the engine a little more receptive to damage if overheated or run excessivly lean.

P.S. Did the rear end work out for you?

cosmo
07-27-2005, 02:27 PM
Havent had a chance to put it in yet. Got my 2 month old son with me and not much time on the weekends so my working on cars goes a little slower right now.

wagone
07-29-2005, 10:33 AM
Do hardened seats on the exhaust side tend to reduce the cracking or exasperate an already fairly serious situation? To wit, although not usually needed on a Stude engine, might the hardened seat improve the situation--or worsen it?
wagone and Avanti I

Roscomacaw
07-29-2005, 10:57 AM
I think it would make things worse. Truth is, it's the relative lack of meat in that OHV 6 head that's it's problem. Now swipe away more meat to press in seats or accomodate larger valves and you've got even LESS meat to the original casting.
Remember - those seats aren't "welded" to the head material. They're only held in place by a tight fit. So they're not gonna ADD any structural integrity to the head itself.[}:)]

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1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

Transtar60
07-29-2005, 02:21 PM
I thought I read that an analysis of the OHV showed it had too much metal in certain places and the replacement heads were worse than the original heads when welded. Something about expansion rates and tolerances. Supposedly , the replacement heads had more metal added to certain spots.

Too bad they didnt(or couldnt) make it a cross flow head like that Kaiser Jeep Tornado OHC six. Course trying to use as many existing engine parts led to some bad compromises.