Don,
Here are the two emails I recently sent to the group. I am running
a large Rochester 2 barrel on a Clifford Performance intake. Additionally,
I have Fenton split exhaust, a high performance cam, and a Dynaflyte dual
point distributor. I have also ported and polished the head and balanced the
engine. Finally, I am currently installing a crank scraper. I have proven
to "high tech" engine guys that there isn't much difference between their
engine and mine.
-----Original Message-----
From: Hargreaves James P IHCO [mailto:HargreavesJP@concord.navy.mil]
Sent: Wednesday, December 06, 2000 9:07 AM
To: 'Oletrucks@autox.team.net'
Subject: RE: [oletrucks] 235 cam and manifold
I have been tinkering with a 235 for some time now. I am running a Clifford
Performance intake that I think works better than the dual or triple carb
intakes. With multiple carb intakes (Edmunds, Offenhauser, McGurk) you will
always have a balancing problem between the carbs. The Clifford works well
with the large two barrel Rochesters or a small (390-410 CFM) four barrel
carb. No balancing or linkage problems. The only problem is that the
Clifford does not have the intake counterbored for the alignment rings. I
recommend adding this feature. I did it by hand with a low speed die
grinder. It took a couple of hours, but I feel it was worth it. (My next
project is to adapt a Chevy Throttle Body Injection - TBI - to the
manifold.)
As for cams go, yes, they help a lot! I am currently running the hottest
grind that I could find. I suggest the grind around #235H would be the best
as I have had a little driveability with the #261H grind. I also converted
the engine to hydraulic lifters, so the grind numbers I just gave have an
'H' for hydraulic. The solid lifter number might be a little different.
You can find the cams in the Clifford catalog. The last cam I bought was in
a Sig Erson box, so Clifford farms them out. Try a local speed shop or
Clifford on the web at http://www.cliffordperformance.com/
Another big stumbling block on these engines is exhaust. I do not care for
the tube headers, as the have a finite life and tend to warp the mounting
flange after time. I was lucky to find a pair of Fenton cast iron headers
cheap and they work great. It is a little difficult to use the stock
mounting pieces. I had to trim them a little to get a perfect fit. I've
heard that someone is reproducing them, but that's all I know. I am very
pleased with the dual exhaust.
If you have to do it in stages, I suggest intake, exhaust, and cam, in that
order. Remember, when the exhaust and cam are changed, the fuel metering
(jets, rods, etc) in the carb will also have to be changed to a larger size
to avoid a lean miss.
-----Original Message-----
From: Hargreaves James P IHCO [mailto:HargreavesJP@concord.navy.mil]
Sent: Thursday, December 07, 2000 12:53 PM
To: oletrucks-digest@autox.team.net
Subject: [oletrucks] RE: 235/clifford intake
- Another member asked some questions about the intake & exhaust that I'm
running on my 235 Chevy. I thought others in the group might also be
interested. -
I couldn't find the Clifford number on their website. They only have one
manifold, which handles a 2 barrel or a four barrel. The manifold is set up
with a standard plenum and uses adapters for either carb. I think they
provide one adapter of your choice.
I started with the intake and a small throat Rochester 2 barrel. There was
too much air speed loss and the engine would dog off the line. I then used
a large Rochester 2 barrel with much better results.
I then added the split exhaust manifolds, and tinkered with them for a
while.
The exhaust manifolds are "Strip" type Fenton dual exhaust manifolds. They
were produced in the 50's for that extra power. I think the fit 216-261.
Mine are marked "235", which was the most common engine to be hopped up.
There was also a "Street" version that had a heat riser to warm the intake
manifold. The street version is VERY uncommon. I didn't have too many
problems with the intake being cold as the aluminum heats faster than the
cast iron intake did. I did have a water heating plate attached to the
intake after the headers were added. I removed it later. I heard that
somebody is reproducing the Fentons, but I don't have any more info than
that.
If I get a chance this weekend, I'll try to get some pictures posted.
- Additional notes:
1. The cam was the last thing I changed on the engine.
2. The oil filter system on my engine has been changed to a full flow
system, similar to the 261. In stead of the usual 50K miles between
rebuilds I got to 108K. I had to rebuild the engine because I broke an
exhaust valve. During teardown I found the cylinder wear to be .001-.002
total. I was able to have the one cylinder sleeved, new pistons, one rod,
new bearings and gaskets, and ALL the valves replaced, and was back on the
road.
3. I'm a little out of your date range. I've got a 1962 C-10 panel.
Happy trucking!
James P. Hargreaves
925.246.2657, DSN 350-2657
"Don't go around saying the world owes you a living. The world owes you
nothing. It was here first."
> --Mark Twain
-----Original Message-----
From: Don Fish [mailto:bluecrow8@hotmail.com]
Sent: Tuesday, December 12, 2000 3:55 AM
To: oletrucks@autox.team.net
Subject: [oletrucks] 2 barrel on a 235?
Hi guys,
Is anyone running a 2 barrel carburetor on their 235? Is the paired, single
bore carb set-up popular due to convention, or is it more efficient too?
I am swapping out my engine and am considering a different intake/exhaust
combination.
Thanks,
Don '54 3100
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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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