The Stovebolt Site Forums The Shop Area Engine Shop 235 Intake sleeves. Are they necessary?

I am about to reinstall my intake and exhaust manifold on a 1956 235. when I removed them for paint and new gaskets, the sleeves were not installed before. So my question is do I need to buy and install the 3 sleeves or just put a new in/exh gasket on and go?

Also I had seperated the intake and exhaust from eachother and for reassembly do i need to bolt them together tightly or loosly before they are mounted to the engine?

Thanks in advance for the help!!

They are not needed, they just make it much easier to line everything up.
I bolt the intake and exhaust loosely together and bolt the assembly to the head without the manifold to head gaskets first, then tighten the bolts, then remove and install manifold to head gaskets and reassemble.

they aren't necessary, however I have no idea how you would get the intake lined up as accurately with the intake ports without them. Given the very poor breathing of these heads, I would use every resource available to me to get the intake flow smooth and unobstructed. And since they are so dirt cheap and readily available, I don't know why you wouldn't use them. Not to mention that during installation they are a great benefit.

loosely,
make the manifold to head then touque in sequence, manifold, then heat box, then back to manifold

I have a used set you can have if you decide you need them. Free.

See photo of Intake Manifold Sleeves
GM # 3.273 GM # 3835506

@ photobucket

http://i669.photobucket.com/albums/vv57/glp0329/ManifoldSealsGMNOS_zps855468b7.jpg

Friesen Chevrolet has ( 5 ) in stock
phone #:402-773-5538

see, free.

Not necessary? You want me to believe GM went to the expense of buying and installing millions of parts that weren't necessary? I'm not buying it.

I'm not sure why exactly they used them on these engines, whether it was to expedite assembly, or to provide a smooth transition from one piece to the next. But the engine will run with out them, much like nearly every other engine on earth. Rendering them technically UN-necessary, however given the price of FREE, and knowing for absolutely sure the ports are lined up perfectly for all practical purposes. I see no reason NOT to use them. I do know I wouldn't assemble an engine without them. Unless of course I was marooned on a deserted island and that was my only way home.

Me neither. They can easily be made from exhaust pipe if none are handy. See here.

Thanks guys, sounds like i'll be getting a set ehh. I am new to 6 cyl world, been into v8's camaros, novas. This is my first 6 build, they were not installed on the engine i tore down and was not sure they were needed. the engine ran great, just looked a mess with all the old greese and rust.

I am building 3 trucks, 1949, 50, 51. love the look of these things

What is the manifold off of? Is it off the 56 or the 49,50 or 51?

really old timers had told me years ago that without them the motors would miss and not idle smoothly--cant see why, but always used them.

CRJ Pilot, off topic but who do you fly for? I'm a controller at ZNY and work the Airspace on J48/74/110/80/152 Q42 etc...

I fly for air wisconsin so i bet i have talked to you at some point.

The intake is off a 1956 235, and it really did idle nice, no intake leaks.

i always use the sleeves.. but you have to be sure it is a 235 intake the 216 are a bit smaller and will not pull up all the way on a 235.. with them being missing i would make sure that is not why they were left off

You still have these sleeves laying around?

Thx,
Derek

There are stepped sleeves available for installing a 216 manifold on a 235 head and keeping the ports and the manifold lined up.
Jerry

They are easy enough to make, just use a piece of exhaust pipe slightly larger than you need, make sure to make them all the same length.

Ed

Thx all, just gonna get some from JJ Inliners