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Re: [oletrucks] Roller rockers in a 235?

To: Old Trucks List <oletrucks@autox.team.net>
Subject: Re: [oletrucks] Roller rockers in a 235?
From: J Forbes <jforb@mindspring.com>
Date: Tue, 09 Dec 2003 09:54:08 -0700
> Hello fellow gear heads. I have my 235 block out for machining and total 
> overhaul.  And I was just thinking, has anyone ever put roller rockers 
> in a 235? Are the arms the same from the SBC? it seems that if this 
> could be done with a bit of machining it might be worth doing. Ideas?

AS mentioned previously, the SBC uses a completely different setup 
(which the later 230/250/292 straight 6s copied).  Roller rockers become 
useful at higher RPM, which is why race cars use them.  They also reduce 
friction just a little bit, which is why late model cars use them.  But 
the 235 is a low rpm engine, with it's long stroke, 4 main bearings, 
long pushrods, etc.  It wouldn't be worth the time.

> Also anyone ever seen one with a blower? Turbo? are cam grinds different 
> for blown motors?

I run a cam in the blown 454 in my 55 Belair that is just a regular sort 
of lumpy street grind...it has rather widely separated lobe 
centers...and works well from 2500 to 5500 rpm.  A blower or turbo 
brings the power band of an engine down, as far as the heads are 
concerned, so a cam with shorter duration than the typical race came 
works well.   I can't find the Patrick's catalog I thought I had, maybe 
it's in Garys room....so I can't help you pick a cam.

My 12 yr old son Gary is thinking of putting EFI on his 235, and he also 
wants to turbocharge it.  Our friend with the machine shop had (and 
hopefully still has) the turbo, intake, and some other stuff from a 
Grand National, which has a 231 cubic inch engine...pretty close!  but I 
wouldn't put more than about 4 or 5 psi boost on a 235, they are not 
very strongly built for this type of stuff.  I suppose it could handle 
more, but it would be a sad lesson if it couldn't.

-- 
Jim

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