The Stovebolt Site Forums The Shop Area Engine Shop Split intake manifold 6 cyl 235

I'm thinking of adding a split manifold to my '65 235 chevy that I put in my '50 5 window chevy PU. I think I want either 2 or 3 single barrel carbs. Any advice on should it be 2 or 3? Anything I should be concerned about? Any ideas on where to get one cheap?
Thanks for the advice,

Martin

I have two single matched Rochesters on the typical Offy intake. There was a intake/Fenton exhaust clearance issue, but they were miinor and corrected with a little intake grinding.The biggest problem was getting my linkage to work correctly without binding.There are better linkage systems now to use.However,if I were to do it again I would seriously consider the 2 barrel Holleys that Tom Langdon sells on Stovebolt Engine Company.They have very smooth operation and adjust very easily.

they also make a adapter that will bolt to your manifold then the two carbs mount onto it that way you leave your stock manilod in place and its easy as pie to change back

Martin,

Here are some thoughts. Generally speaking, three carburetors are too much for this engine without additional internal modifications.

There can also be firewall clearance issues when attempting to use three carburetors in a AD rig.

Stuart

no to mention now you have 3 carbs to adjust instead of 2. i am new at his stuff but do the multi carb intakes have the same fuel puddling issues as the orig 1 carb setups?

There is no good linkage for that application that I know of and I think the Rochester B is blamed unfairly for that. IMO the only accurate way to operate the carbs simultaneously is with a pivoting rod as is done with the Holley/Weber setup or any vintage intake equipped with such. Use a manifold with an integral pivot rod and you’ll get any carbs to sing together. Actuating multiple carbs equally, especially on the new Fenton intake (11”apart) is a lot to ask of the “floating” linkage. If I were to do it again I would use a vintage 216 dual intake with solid linkage and a pair of small Rochester B’s with a 216 split stock exhaust.

"I'm thinking of adding a split manifold to my '65 235 chevy"

Probably a typo but hopefully you are aware that 235 production ended with the 62' model year except for a minor handful of exceptions.

I have the 2 x 2bbl setup mentioned above and don't particularly recommend it. Better to do a small 390 CFM Holley 4bbl on a Howards intake. Just less hassle all around.

That's true. I did the Holley/Webber 2 bbl conversion from Langdon's and couldn't find the jets. Those jets have long been discontinued. You can still rejet the carb, but you have to solder a pair of jets closed, and then drill the size hole you want in them. What a hassle.

A nice Holley 4 bbl would just be so much easier.

My problem with the Holley/Webber conversion is the funky looking air cleaners. They are flat out ugly and don't look anything like any of the vintage air cleaners. For that matter, the carbs don't either. The air cleaners look like upside down sauce pans off of the Food Network.
I think Curt B. is right on the money. I was running an Offy 1 x 2 with a floating linkage and never, never could get my 261 to run right, even with two NOS Rochesters. I found a 216 Edelbrock with a solid linkage set up and put those NOS Rochesters on it. You couldn't ask for a nicer, more period correct, better running set up. No problems!
Just my thoughts.
Joe

hey 6 cylinders,

i am looking at a 57 261 right now for my 46 1/2t pu. i want to build a period correct rod. can you explain the floating linkage vs solid linkage?? with the 216 edel intake what exhaust are yoou running? thanks

Martin,

Here's a pic of Joe's engine. To me it doesn't get sweeter than this.

http://www.joefuchs.net/gallery/gallery.php?eventid=5

Bigedpa,

Any intake with a solid linkage provision will have 2 “ears” with holes in them for a rod to be held parallel to the head. On Edmunds intakes the rod runs thru the casting on the opposite side so position is flexible as long as pivoting is possible. The throttle is attached to the rod by means of an arm and then the rod tranfers the motion to the carbs. There’s buckets of intakes to look at in this thread, many with solid linkages and even an advertisement for a Mcgurk 3 carb setup which you can see a floating linkage:

http://www.jalopyjournal.com/forum/showthread.php?t=200740&showall=1





Ouch! And you didn’t bring up my biggest concern with that setup. The bottleneck in the adapters chokes off one of the 2 barrels from what I’ve read.

Hello,

Thanks for your reply to my post. No, I was unaware that the 235's ended in '62. I did really think it was a 235 6 cyl. I got it out of a 1965 Chevy Biscayne. It bolted right up to what I had in there. Appears to be the original 4 speed. The truck did have a newer 6 cyl. in it but I do not know what year. It was frozen up so, rather than try to fix it, a friend gave this one to me. He was putting in a V-8. I thought free was a good price. Would this new one then be a 230? Instead of a 235?

Thanks,

Martin

A photo would be most useful.

How many bolts hold the valve cover to the head? This information would help to determine if it is an older 216/235 or a newer 235/261 or a newer six (230/250/292, maybe).

Three bolts on each side of the valve cover.

Martin

I'll post some pictures of the engine as soon as I figure out how to post them.

Thanks,

Martin

Here are some pictures

http://oreschniggtruckblog.blogspot.com/

Martin

Hey Martin, I believe you have yourself a 250 there...might want to get the #'s off the side to check before ordering parts

Thanks for the clarification. I'll get the number today after work. I'm so new at all this. It's been a real learning experience for what I've done so far. Sometimes I think I'm in "over my head". I'm lucky I have a few friends that know something about this type of "stuff". I look forward to learning from all you on this site.

Your never "over your head" as long as you don't give up. Be patient, and when you think you are ready to set it on fire, walk away, turn off the light to the shop, and revisit in a couple of days. Remember this isn't a race, as long as you finish you will be happy with what you end up with, whatever that is.

OK, I wrote down all the numbers I could find. The number right behind the distributor is 4886F7; the number exactly in the middle of the spark plugs (3 on each side) is 4680; and the number on top of the intake manifold (towards the front of the engine) is 8859381; and underneath that number is GM9.
I hope this helps identify what engine I have! Thanks for all your comments!!!
Martin

Hi Folks,

Any idea what kind of engine I've got. Please see the previous post.

Thanks for all your help.

Martin

Hey cowboycpa;
I have a freebee chevy six that may turn out tot be a 230 instead of a 235. What ultimately did you decide about your mystery engine and what determined its displacement and year? What vehicle are you putting it in and how well did it fit?
tinnocker