The Clifford heated intake and Edelbrock 600 are what I use on my GMC 302.
It's a good combination. The 500 CFM Edelbrock would probably be a better
choice for a 235, but the 600 can be jetted down to work OK. The
documentation that comes with the carb is very good, showing how to go rich
or lean in various stages. The Edlebrock tech line is excellent as well. Be
sure to mount the carb with primaries outboard, or fuel distribution will be
uneven. This complicates linkage somewhat, but a Lokar cable connected to a
bell crank will solve that.
Mileage should improve, providing you don't get into the secondaries too
often. Hard to resist, though.
Re CFM flow figures, remember that modern 4 barrel carbs are rated for V8
applications. The lower volumetric efficiency of an inline 6 means that a
'600 CFM' carb won't really deliver 600 CFM on a 235. And also,
over-carburetion is really not as much of a problem on an engine with a
low-end torque bias, like a 235 or 302. Your machinist is right on with the
750 CFM number for track use - but that carb really isn't flowing 750 CFM on
an inline 6.
Re your choice of Clifford headers - IMHO for street applications,
especially daily driving, cast iron headers are superior to tube headers, as
they run cooler, quieter, and last forever. Despite some reported quality
problems with Fentons of late, that's what I'd use. Or check Night Prowlers
catalog, they have some very nicely done split manifolds and econo steel
headers for 235's. They aren't on the web yet, that I know of. They are
located in Lamar, Missouri (417) 682-3685.
Jack / Winter Park FL
----- Original Message -----
From: <DeLibre@aol.com>
To: <oletrucks-digest@autox.team.net>
Sent: Wednesday, December 29, 1999 10:38 AM
Subject: [oletrucks] 235ci and 4BB Experiences
> I'm ordering a Clifford water-heated intake manifold for my 235ci. Its
> getting rebuilt with a mild performance cam, new rings et. al., Clifford
> Headers, Fisher harmonic dampener, dual-point distributor, etc., and I'm
> gonna drop a 4-barrel on the new manifold.
>
> Folks at Cliffords tell me that they're having to re-jet their Weber 370
cfm
> carbs on 235ci engines- that 370cfm is just too much for these engines,
much
> less 600cfm.
>
> Impulsive guy that I am, I had scaled back from my machinist's suggestion
> that I get something around 750cfm for the engine, and bought a Edelbrock
> Performer series 600cfm with electric choke (based on good words from
folks
> in this group and other web resources). My machinist builds GM inlines
for
> Vintage Stock, so I think he's biased on the built-for-track, not
> daily-driver side, and going larger than I'll need for street.
>
> Anyways, I'm wondering if anyone has already dropped a 4BB on their 235,
what
> size and make it was, and what the results were- power, mileage,
dick-around
> factor to get it consistently working, etc.
>
> I drive mine every day. I don't mind increased performance, have gotten
sick
> of a leaky stock Rochester Model B w/ questionable stock filter, but
drive
> 38 miles to work in my ole truck every day, so mileage is a consideration.
> 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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