The Stovebolt Site Forums The Shop Area Engine Shop Old OTC 235 out of 56 Chevy

I think I made a pretty good score last night. I met a nice old guy that was downsizing and getting rid of alot of parts etc. Among other things I picked up a crate 235 for $100 that he pulled out of his 56 Chevy car in 1977 and stored in his garage since then. It was running when he pulled it and it's in relatively great shape. It came with dual exhaust manifolds and an Edelbrock dual one barrel intake.
Now for the decision. I'd like to give my dump truck some much needed power. It has a .060" over 1937 216 in it now that runs perfect. There's no "real" need to swap it out, but...
I have a 1954 261 and now this 1959 counter 235. I could clean up and run either engine as is or... I was thinking about taking the 838 head off the 235 and putting it on the 261 for more compression.
Any reason anyone can think of that I wouldn't want to molest the 235?
I know a single carb is probably better for day to day, but I think a dual intake and exhaust would be pretty cool. Hot Rod the dump a little for something different while keeping it more with the period.

I'm a firm believer in the "If it ain't broke, don't fix it" philosophy when it comes to antique cars.

On one hand, you have a perfectly running engine already installed in your truck and you say you don't need more power.

On the other hand you have an engine that is essentially a "rebuildable core", regardless of the seller's claims. Even if it was "running when pulled," 50 years sitting in a garage didn't do it any favors.

You can either open a large can of worms, or be happy with what you have.

The 56 235 motor is a pretty good motor. First year for precision bearings (read that as no shims needed), first year for the neoprene rear seal, first year for the 848 head.

The 54 261 is also a good motor. Of all the 261 blocks, the 54 has the thickest cylinder walls so can theoretically be bored out a little larger than the 56-62 blocks. One the other hand, uses shimmed bearings, rope rear main seal, low compression head (depending on the casting, 86.2 or 95.5).

So, theoretically you could rebuild the 261, send the cam to Schneider Racing Cams in San Diego and have them put a mild grind on the cam, rebuild the head (if you really felt like playing you can have the head rebuilt with larger valves, stainless Manley Street Flow for the exhaust, GM 50-52 powerglide intake valves, open the throats a bit, machine the valve stems for a modern PC seal, drill the steam holes in the 848 head, and you would have a pretty good runner with the dual manifold and exhaust.

I completely understand the if it ain’t broke sentiment. I do. But I have a different take. I love to tinker. I am ok with failure with some of my tinkering. It comes with the territory. I do not want to be in the nursing home stuck in a bed lamenting over what I did not do, but rather think about the things I did do. So I work hard, and then I play, and play and play.

If you want to play, go to it. The worse that can happen is you don’t like it. Then you will redo a few things and try again until you do. When the window closes on your physical and/or mental and/or financial ability to play closes, with very few exceptions, it generally does not reopen. No better time than now!

As much as I do appreciate your response Otto, I'm in Dragsix's camp. I like to play.
I'd love to trick out the 261, but it does sound like the 235 might be the way to go for me. I like the better bearings and modern seals. A good friend owns a local machine shop so any machine work that I might need doesn't cost me anything.
Bigger valves, decking the block/machining some off the head if there's room for added compression and a little port matching etc if necessary can do wonders for making engines breath better.
I'll probably rebuild the 261 also and sell it along with the current motor in the truck.
My 41 dump is never going to be a tri 5 or my 69 Camaro, but I'd like to give it a little extra character by way of some extra power and subtle engine goodies.

What you might want to do is reach out to hot rod Lincoln and ask him to walk you through the rear seal conversion. I have never done one and not sure how to instruct a basic machine shop how to do it, but Jerry can. If you have access to a machine shop that has the capability, and it looks like you do, I would do the conversion.

Gotcha. I enjoy driving my vehicles a lot more than I do working on them. Except for maintenance and needed repairs, I don't go looking for more work.

What are you going to do with the good running 216?

The 261 can be built to 300 cubic inches with 96MM pistons and replaceable flanged sleeves for a Yanmar diesel, a 4 3/8" stroker crankshaft, and H beam rods for a big block Chevy V8. Use the 848 head with the big valves that Mike suggested, (about 9.5:1 compression with flat top pistons) and machine the back of the block for a full circle lip oil seal. The big problem with that buildup will be finding a machinist who knows what he's doing to make it happen.

Mike, the lip seal conversion is simple- - - -use a portable boring bar mounted to a plate bolted to the back of the block, center up in the main bearing bore, and start whittling. I made my own mounting fixture from a piece of 3/4" thick steel plate. The seal I use takes a 4 3/4" counterbore 3/8" deep. The seal part number is a Timken 417210 or equivalent. The seal lip has enough flexibility to handle a 3 7/8" stainless steel Speedy Sleeve on the crankshaft. That same seal also works on a 216 and a 235- - - -same setup.
Jerry

I completely appreciate enjoying driving over time out for mods. In truth I enjoy one as much as the other to a point. I'm sure that's one of the reasons I haven't blown my 69 back apart to paint it. It's currently in primer. I love the look, but primer doesn't do much for protection...
I'm sure I'd sell the 216 once I made the swap.

If I were building a true hotrod that I wanted to keep the 6 in I'd definitely go the 261 route. My machinist friend does have all the equipment like the portable boreing machine. I have other priorities for my funds right now for parts, but who knows. Maybe I'll build it that way to sell it. I don't know what the market looks like.
The 235 is an over the counter the PO bought so I believe that means it's a 59+ motor. The date code is I185. If it truly is a counter motor It seems like that should be 1965, but if it's actually a replacement block it could be 55. Seems more likely. The 848 head is H246. I started assessing it last night. Unfortunately it was stored on its side in a garage since 1977 so it was pretty stiff trying to turn it over. A little PB Blaster and Marvel Mystery Oil in the cylinders helped get thing moving again. I haven't pulled the head or oil pan, but I'll assume I'm going to throw bearings, rings and a head job in it at a minimum.

I did a quick mock up to make sure I had all the linkage, bolts, pieces etc. It's going to look pretty slick. I suspect it will perform well also. I didn't put the dual exhaust manifold on, but it will definitely be part of the build.
I'm not sure if I'll use the Mallory dual point distributor and Mallory coil. They're 12v and I'd rather not convert the truck from 6v, but I might. I have a 12v generator with mount and a 12v starter so that's most of the cost and battle I think. At least the generator looks like the 6v and not a modern alternator.

Be aware that 6v and 12v starters use different flywheels so they have to be swapped as a set.

Thanks for the heads up. I have the correct flywheel with the motor. I'll make sure I keep and label it.

Disregard the following if you are already aware:

A 1941 dump truck will be geared for the purpose of hauling heavy loads, at slow speeds, on 1940ish roads. Replacing the 216 with a 261 will definitely give you more torque to haul heavier loads but you may not gain much in MPH. People drive much faster today, and in my area, they always go over the speed limit. Another consideration is that big truck rear axle parts, tires and brakes by themselves can effectively clean your wallet. Some of these parts are not reproduced and finding good used parts can be very difficult. The other possibility is a frame/drivetrain swap, but any on-going discussion would have to be moved from this forum section.

The engine in your pictures has the low mount water pump, which will put the fan too low on the radiator in your 41 truck. You'll need a relocation plate to install the 216 water pump on the later block. Stovebolt forum member "Pre-68 Dave" makes and sells those plates, so send him a message about purchasing one. Other vendors buy his plates and mark up the price!
Jerry

Thanks BuoyMaker. All things in my calculations.
Jerry,
Before I ask anyone else, please tell me about the adapter plate. What is it about the later block that won't allow swapping parts like the water pump between the 216 and the 235?

Thanks.

Here's a great thread on your Water Pump Relocation topic. It should answer lots of your questions and point you to where you can get the relocation kit.

Thanks!

For anyone that comes across this thread, here are some pics from: Pre '68 Dave's Chevy 6 VCCA Presentation
I highly suggest that anyone that likes to know a little more check out his blog.

He gives an excellent visual of what's going on with the water pump between the early and late 216, 235 & 261 engines.

Here's a direct link to his Blog on the Relocation Adapter too.

👍
I ordered one last night. I'll be building the 235 sooner than I was planning.

Stand by for change #36....
I pulled both the 235 and 261 apart last night to start assessing what I'm dealing with. I think I've convinced myself to go with the 261. As they say, "There's No Replacement for Displacement." The shimmed bearings and rope seal were turning me off. The rope seal is a non issue. I can have the block modified to accept the one piece rear main seal.
That leaves the shimming of the bearings that I didn't like the idea of. I kept thinking about why that would be necessary and it occurred to me that it wouldn't be if you turned the crank to account for the clearance you want. It just takes an added step. Problem solved IMO.
I took the 848 head off the 235 and put it on the 261 for mock up. I'm sure it was said, but another bulb went off. I don't need the water pump adapter on the 261. I bought one for the 235 which is fine, but it's another thing I just didn't quite like the idea of. I'll keep it with the 235 and see if I end up using it when I rebuild that motor.

Does your 848 head have the extra water passage holes for the 261 or will you drill them?

You need to be aware that the main bearings for that year of 261 are almost nonexistent. It's possible to use the later model mains, but you'll need to do a little grinding on the block where the anti-rotate tabs fit at the parting line between the block and the main cap. PM or call me for the right part number mains and how to make them fit.
Jerry

I'm not sure yet. Not a big deal either way. It's an easy modification from what I've seen.


Thanks for the heads up Jerry. I'll definitely keep you in mind when I'm ready to start ordering.

Even with the new design main bearings, it's a definite possibility that you might need to use shims to establish the correct oil clearance. Unless your machinist is willing to do a line bore job with four different bearing bore diameters, (most won't even attempt it) shimming for the right oil clearance is almost a "must do" situation. One main bearing on John's 261 needed a single shim to correct the clearance, and it was machined for the later model bearings.

BTW- - - -I've got the line bore tooling and I know how to handle that little chore, but I'm older than dirt!
Jerry

I hear you. Thankfully I'm blessed to have a good friend that's an amazing machinist. He owns a local performance engine machining/building business. He isn't exactly crusty yet, but he has some years on him. He has a lot of the obscure knowledge to work on old iron also. Like me, what he doesn't know he sees as a challenge to learn something new. In addition to all the modern equipment and dyno he also has a lot of tools that probably are now considered oddities and are mostly found in museums. I know he won't want to use shims and he'll do what it takes for me. Maybe he'll say to just use shims. Who knows. If he's alright with it I'm alright.
In the end, when I assemble it, I'll be comfortable with the choices.

Another option which I'm setting up to do on all the stovebolt engines I intend to build going forward is to machine all the main bearing journals to the same diameter (Chevy small block 400) and put reducer bushings in the block to equalize the bore sizes. That eliminates the 4-size bore problem. Then I'll line bore and line hone the block one time and have newer, more affordable main bearings to install. I'll also machine the thrust faces on the #3 main web to use a permanently installed bronze thrust washer instead of a flanged bearing shell to control crankshaft thrust.
Jerry

I haven't gotten to measure anything yet. Why will you need reducer bushings? Does it really have to be opened up so much that there aren't over sized bearings that'll accomodate it?

I fat fingered a key and erased a long post- - - -I've explained the main bearing modification several times and got either ignored, or even ridiculed by one so-called "machinist" on the forum who's now on my "ignore" list. Machining and regrinding all the crankshaft main bearing journals to a smaller diameter and sleeving the bores in the block eliminates the four different main bearing bores. A small block 400 Chevy main bearing then fits all the way from front to rear and there are permanently installed bronze thrust washers controlling crankshaft end play. It also reduces rotating drag and the end result is more torque out the back end.
Jerry

I hate the deleted post before you hit submit trick!
I understand the need to grind the crank to a consistent size. Are you saying the current bores are too big to machine for a standard sized bearing? Besides thrust is that why you're sleeving them?
Edit!!! Lightbulb just went off. I see why you need the sleeves now.

Ther's a main bearing that's used in a Buick 403 engine, and several Olds and Cadillac engines that will allow the stovebolt mains to remain in place and be bored and line honed to fit the smaller bearings. They will serve as reducer shims to allow the same size bearing bores to be used front to rear. The Federal-Mogul part number is 4281M. The bored-out bearing shells will be retained in the block and the cap by flat head Allen screws and red LocTite. The shaft diameter on all the main journals will be 2.498-2.499". That approach will allow the original stovebolt thrust flanges on the #3 bearing to remain in use.
Jerry

Thanks Jerry. I'll have to look at it when I get to the machining point.

One more FYI- - - -If your machinist is comfortable doing it, the main bearing journals on the crankshaft can be roughed out on a lathe to within a few thousandths over the desired diameter, and then ground and polished to finish size. That eliminates wear and tear on those expensive crankshaft grinding wheels.
Jerry

Thanks. I leave those kind of details to the artist. 😉

Hmmmm- - - - -my shop isn't quite that fancy, and some of my equipment is older than me. One of my Van Norman boring bars has a brass tag attached that says "wartime production finish". They were embarrassed to turn out something that rough looking. I can still hold a +/- .0005" diameter tolerance with it, though!
Jerry

It's not about how fancy your equipment is. It's about knowing what to do with the equipment you have.This is his finishing shop. The one next door is where he does the tear down and cleaning etc. It's where the antique tools are also. He's a one man band, but he turns out some pretty awesome results.