Eric,
The old log manifolds from McGurk and Howard do a pretty good job of
distributing the fuel mixture. Having that log as a plenum also means you
don't have to have the carbs perfectly synchronized.
I've seen some "stub" manifold setups that seem to work OK on race cars, but
not sure how they would do on a street engine. Interesting idea, if you try
it, please let us know how it works.
I don't think the copper tubing is going to help much on the log intake,
though. You need a length of half-round or 3-sides-of-a-square aluminum
tubing welded to the back of the plenum, with pipe threads on each end, so
the hot coolant makes full contact with as much of the manifold as
possible. Alloy dissipates heat pretty quickly, so you need to get the
entire thing as hot as possible. I had some problems finding a welder who
even understood what I was trying to accomplish, much less had the skill to
do it without burning holes in the manifold.....It turned out well though,
and really made a noticeable difference.
Jack / Winter Park FL (finally coolin' off a little)
----- Original Message -----
From: Eric Johnson <j.eric1@worldnet.att.net>
To: OleTruck list <oletrucks@autox.team.net>
Sent: Friday, October 22, 1999 6:46 PM
Subject: [oletrucks] 3x1 manifold
> I was wondering what the purpose of the log manifold is?
> I have an old 5 port McGurk with 3-1brl carbs hooked to a 302 head thats
> hooked to a 270 block. I was wondering if I take off my log and bolt my
> carbs right on to my down draft tubes if this would work any better or
> worse.
> It would be like motorcycles are and I wouldn't have to heat any manifold.
> The down draft tubes get hot on thier own, being bolted up to the head. I
> undestand why the manifold if you're going to use 1,2 or 5 carbs, but if
you
> got 3 with a 3 port head, why the manifold. I hope somebody can staighten
me
> out on this, cause I have been wondering about this for a long time. But
in
> the mean time I'm going to strap some 1/2" soft copper to the sides of the
> log and run my coolant thru there since I finally understand that it won't
> work right without it.
> Thanks for everything
> Eric 48 Carryall
>
> oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
>
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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