Anyone happen to know, or have a convenient way to measure, what the center to center measurement is for lifter bores on a 235?
Given the wide array of roller cam conversion kits available nowadays, I got to thinking maybe there was a spacing match with a common V8 application.
If so, a guy could buy off-the-shelf conversion “tie-bar” roller lifters, have the 235 lifter bores sleeved to fit them, and get a roller cam ground. Pretty minimal amount of custom or complex or expensive machine work.
I use MOPAR big block (383-440) tie bar roller lifters. I have a 216 block set up that way, but I don't have a cam for it yet. With the lifter bores sleeved a little they're a good fit. A piece of 1" OD seamless steel tubing works well to make the sleeves. Be sure the cam core you get reground for a roller lobe is steel, not cast iron. Schneider cams says that a cast iron/roller setup has a lifespan measured in minutes. 216 and early 235s have steel cams, but you need to make sleeves to press onto the bearing journals to bring the diameter up to late 235/261 size. 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!
Put you standard digital calipers in the bore fully open and the zero the calipers. Then without re-zeroing the caliper measure outside edge to outside edge. That is your center to center measurement.
Originally Posted by JW51
Anyone happen to know, or have a convenient way to measure, what the center to center measurement is for lifter bores on a 235?
Given the wide array of roller cam conversion kits available nowadays, I got to thinking maybe there was a spacing match with a common V8 application.
If so, a guy could buy off-the-shelf conversion “tie-bar” roller lifters, have the 235 lifter bores sleeved to fit them, and get a roller cam ground. Pretty minimal amount of custom or complex or expensive machine work.
I'm also in the process of making a roller cam core, using two pieces of solid round steel stock, press-fitted onto a distributor gear salvaged from a worn out stovebolt cam. I'll make a round shank about 1" in diameter on both sides of the gear, bore the end pieces a little bit undersize, then press fit and taper-pin the assembly together. Once that's done, bearing journals and lobe blanks can be machined on my lathe for the cam grinder to finish 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!
Thanks, Mick. I just didn’t have an engine handy to do that measuring without tearing into the one in my truck.
If anyone knows if 216 lifter spacing is the same as a 235 (I suspect it is), I have a bare 216 block that I could measure for you.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
The big block MOPAR roller lifters with the tie bar work- - - -I have a 216 block set up that way already. The lifter bores need to be sleeved down approximately .030". Yes, the 216 and 235 lobe and bearing spacing is the same- - - -distributor drive gear also- - -the only difference is the diameter of the cam bearings. I also have a 235 cam with the bearing journals turned down to 216/spray oiler 235 diameter. It fits properly. Not a guesstimate- - - -I've done it! 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!
Mick, Mine is at least inside the garage, I just need to turn it around so I can get to the lifter bore. I'll see if I can make that measurement tomorrow.
No need for you to dig that block out of the snow.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
It will be necessary to fabricate pushrods with the correct length and end shape, since the lifter end of the pushrod needs a 5/16" ball. I'm going to use thick wall 3/8" OD stainless steel tubing and press-fit end pieces from www.pushrods.net
I'm also working on a project to install 18MM ID Torrington needle bearings in stovebolt rocker arms, on reduced diameter original rocker shafts. 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!
I got my pushrods from Butler performance in Lawrenceburg, TN. They actually have Smith Bros. make them. They were dropped shipped to me so they came fast. I got 12 each, 3/8” X .145” wall chromoly, 3/8” ball on the lifter side, 5/16” ball on the rocker side, 12.500 OA, exactly 2 years ago. Cost me $233.00 at that time. I'd join in the discussion, but I'm working on a GMC 302. However, I believe the original builder used Chevy Big Block roller lifters for this project.
Jerry could throw a rock to Lawrenceburg, TN from his place.
But not for another week or so. Doctor's orders.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
My favorite local gun shop is just a little south of Lawrenceburg, in Ethridge. That might be worth a short road trip once I get cleared to drive! 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!
I just measured the lifter bores on the bare 216 block I have. As close as I can measure (that thing is sludgy and kind of like the proverbial tar baby ) the spacing between lifters is 1-7/8".
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
As soon as I can make a trip to the shop without the docs having a meltdown, I'll post some pictures of a set of MOPAR roller lifters in a stovebolt block- - - - -"We test, not guess"! Been there, done that- - - - -got the T shirt! 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!
So…picking this topic back up. Seems like the steel cam core is the most limiting factor.
Jerry - Would a grinder like Schneider actually take on a regrind if you did the sleeve thing to bring journals up to size? Or would that scare them off?
Another wild idea: DLC (diamond like coating). There are companies doing that to all kinds of valve train components nowadays. Wonder if it could be done to a 235 cam (cast iron) after a roller grind to make it live? I also have zero idea what that coating costs. Might be absurdly expensive.
Yes, Schneider said they could put a roller lobe onto a stovebolt steel core, with the only limitation being the dimensions of the original lobe. I'm also working on an idea to graft two pieces of full round steel stock onto a stovebolt cam gear, and machining blank lobes into the correct position to be ground into whatever shape is required. The only limit there is the diameter of the #3 cam bearing. When I toured the Comp Cams facility in Memphis several years ago, they showed me a NASCAR roller cam core for a small block Chevy- - - - -it was nothing but a solid round billet of steel with a distributor drive gear machined onto the end. Their price for it was $3K- - - -before they started whittling on it! 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!
OK- - - - -as promised (threatened, maybe?) Pics! The block is a 1948 216, which has the same lifter diameter and lobe spacing as a pressure oiler 235/261.
"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 2.739 measurement is outside to outside of the roller lifters, installed in the sleeved down bores. That would make the lifter bore spacing centerline 1.835", +/- measurement error. Jerry
Last edited by Hotrod Lincoln; 12/10/20251:26 AM.
"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!
Just a thought- - - -sleeving the block and then gun-drilling the oil passage through the lifter bores might be a good way to substitute Ford/AMC/MOPAR hydraulic lifters for the notoriously unreliable Chevy hydraulic lifters in the late model blocks with the hydraulic lifter option available. All of them have the same .904" diameter. Custom pushrods would be required. 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!
No doubt. That is also a jobber price. Just wanted to show it's not crazy expensive. It would be interesting to find out what the price is today. They also have better/efficient machines now and more people have them.
A roller cam core can be made by splicing a piece of 2 1/4" round stock such as drill rod or tool steel onto either side of the distributor gear, and turning them down to make bearing journals and lobe blanks. Even the fuel pump lobe can be put onto the shaft by a cam grinder if you choose not to use an electric pump. The maximum lobe lift will be determined by the diameter of the #3 cam bearing journal, which is 2.029" on a 235/261 cam. A 36" piece of 1018 alloy steel costs $95.00 on Ebay, with free shipping, enough to make both halves of a spliced-together cam core. 1018 can be surface-hardened if desired, by case hardening or carburizing, leaving a hard surface and a tough core. 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!
That would make the lifter bore spacing centerline 1.835", +/- measurement error. Jerry
That tracks with what I got. 1-7/8" is 1.875" in decimal.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
One more pic- - - - -here's the tie bar lifters with a 216 cam- - - - -the 1.875 spacing looks accurate:
"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!
A reminder: the stock cam cannot be re-ground to a roller lobe shape - not enough material. The roller lobe nose is very broad, the stock lobe is "pointy".
Last edited by klhansen; 01/12/202612:46 AM. Reason: typo fixup