I'm wondering about how much compression a 216 head can handle without having blown gasket problems. The engine I'm hallucinating about building is going to have a bit over 260 cubic inches in a 216 block, and the increased displacement should bump the compression ratio up into the high 8's or low 9's if my thumbnail calculations are close to correct. I'm thinking about contacting ARP to see if they can supply studs the right length instead of relying on 70+ year old bolts to lock the head down tight onto the gasket. Comments? Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
All I will say is that this forum doesn't seem to be filled with questions concerning blown head gasket issues. Cracked heads yes, blown head gaskets? No. Folks acquire these trucks with old engines which have been ridden hard put away wet. We get all kinds of questions about all kinds of issues. Lacking from that list of questions is "what do I do about the warped head, or why do I keep blowing head gaskets?" Given this less than scientific observation, I wouldn't worry about head gasket failure on these tractor engines. It does not seem to be inherent to these engines. The GM engineers seem to have added enough margin of error in their head/block design, effectively eliminating blown head gasket issues.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
My main concern is that the 216 head has fewer bolts, and whatever information there might be on hotrodding a 216 was probably written by people who make me look like a young sprout! What I'm trying to develop is an engine that will pass the visual inspection of people who know what to look for, 216 VS 235, and crank out torque similar to a 261. It will be basically an increased-stroke 235 rotating assembly hidden inside a 216 block, modified for full-pressure oiling. I'm pretty sure I can squeeze a 261 camshaft with reduced-diameter bearing journals in there as well. I love to build "sleeper" engines that perform way above what they appear to be on the outside. A lot of the engines I built for "claimer" racing on the round tracks fit that category. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Go ahead and put out a lot of effort, raise the hood at a car show or dragstrip and 99% or more so wouldn’t know the difference no matter what you did or didn’t do to it.
What about an increased stroke rotating assembly in the 235, J
With the length of the recycled NASCAR connecting rods I have available for this project, some milling of the 235 block will be required. The same stroked crankshaft can be fitted to a 235 or a 261, as long as you're willing to mill the block down about 1/8" to get the piston close to the top of the block. The 235 ends up around 270 cubic inches, depending on the bore size, and the 261 ends up over 300. When the 216 block is used, no milling is required, but the thrust bearing area of the 235 crankshaft needs to be widened or the main bearing web of the 216 block would have to be narrowed by 3/16". The prototype engine I'm in the process of building up has a widened crankshaft flange. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Jerry, have you thought about boring the cam bearing hole bigger to use the big journal cams? That is the only way to get a new rather than reground cam, unless they have just recently released a batch of new forgings/castings whatever they are now.
No need to do that- - - -I took a junk 235 cam recently, and turned the bearing journals down to 216 size- - - - -it slips right in and turns with no problems. I'm planning on modifying a new Elgin Industries 261 cam to use in the stroker engine. Even with the increased stroke, the NASCAR rods have a smaller cross section than the 216 rods, and there should be more than enough cam lobe clearance. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
the reason I say that is I thought I could do that too. Turns out I had to have the cam reground to fit through the last hole. Then Delta lost my cam, and I ended up with a used reground cam anyway. Like really reground, at least the second time around. Make sure they grind it with enough off the backside to clear all the holes is all I'm saying.
HMMMMM- - - - -I'll need to recheck that as I go. The one I machined down fit without any problems. I've got a trashed-out 261 with a cam that's not going to be run in another engine, so I can use it for experimenting with the fit. Thanks for the heads-up! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!