Yes! It runs!!!!! http://www.youtube.com/watch?v=JugKNg1lLCQ&feature=youtu.be Just one carb now, but will soon be three with progressive linkage! Engine specs: 1954 261cui, new pistons, new bearings (have not bored or grinded anything) Engine block milled 1mm (0,039 inch) 848 head milled 1,6mm (0,063 inch) Combustionchamber grinded some around exhaust valves Intake and exhaust valves 0,10 inch larger, reamed ports to match bigger valves. Sig Erson double valvesprings with aluminium retainers. Wolverine camshaft and solid lifters( cam lift .279 intake .273 exhaust) (valve lift .405 & .387) (duration .291& .275) Cromemoly tubular pushrods Offenhauser three carb intake Fenton headers Mallory dual point distributor (two piece flat top cap) /Johan
Great info. on the 261. Nothing like a inline 6. Inliners International has a ton of info. and a great bunch of guys and gals. Join up you'll be glad you did. Thanks for the post....JT
The only problem with Inliners Is that our search feature sucks so finding all that good info is not easy. If I can help you find stuff let me know. http://www.inliners.org/
I am pasting an edited post (in red) I made in March of 2012 on the Wayne Speed Equipment thread There is at least one DOHC head that was made for a 261 Chev and successfully run in an oval track race car. The July 1982 issue of “12 port NEWS” has a five page cover story written in detail by Herb Hall. This is the club magazine of the INLINERS INTERNATIONAL <O The current January/February 2012 issue of the 12 port NEWS has a follow on article describing the current build of the 1930’s Big Car that is being powered by this engine. I will include a photo below. <O Coincidently, that 1982 issue also has 4 pages of interview with Bob Toros regarding the progression of the <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com</st1:City>Wayne</ST1 and Horning engines and his involvement in ownership and production. <O Back issues of the '82 article are not available. As the engine is being totally rebuilt starting this fall, I will be taking new pictures and plan to copy and edit the old article and submit it for republication. Lastly, if anyone is aware of any other DOHC Chev or GMC engines, please share that information <!-- / message --><!-- attachments -->
I'll check at our next meeting and see if anyone has the '82 article. Also for those who don't know on the Inliner site click "Historical" to see a 9 part history of the 12 head. Wayne Horning was a member of our chapter of Inliners Though I only saw him once. That DOC build is great.
Lots of good information in this thread...I recently acquired a nice 261 that is complete and appears to have been overhauled. I removed it from a '56 or a '57 model Chevrolet 6500 truck. The engine is a newer model though, based on the casting number. Not sure what I'm going to do with it just yet.
Hope I'm in the right spot. I have a 1954 Chev 261 That I had rebuilt. Built by Dave Dunbar in Plympton, Mass. I sold the '37 I was going to put it in back in May. Anybody interested? Will sell local if'n anyone would be interested. I'm about 20 miles south of Boston. Jay Y.
Hello Jay, I might be interested. I'm not far. I'm in Connecticut. What can you tell me about the engine? Dom
I built the 261 for my '54 sedan, about 14 years ago. Since the initial build, I've gone back through the engine and made some upgrades. The initial build included re-grinding the crank, reconditioning the rods, boring and honing the block to .080" over, etc... The cylinder head is a completely rebuilt '54 power glide head with the steam holes drilled and some mild bowl and port work. I chose the Howard's "3/4 Race" cam and tubular pushrods, from Patrick's. After the first build, I was running an Offy dual intake with two Rochester single barrel carbs, and a pair of Clifford's shorty tube headers. I rebuilt the stock Delco distributor and put in a Pertronix conversion. The engine ran well in this configuration. A few years back I decided to make some changes to the car and figured that would be a good time for some engine updates too. The engine was completely disassembled and cleaned, and I plugged/ drilled and tapped the oil passages for full pressure oiling. I machined the block to accept a Ford Power Stroke one-piece rear main seal, to eliminate the old rope seal. I also modified the Offy intake and added a spacer between the cylinder head and the thermostat housing, so I could run coolant through the intake. I ditched the Rochester carbs and bought a pair of Carter-Weber progressive two-barrels from Langdon's Stovebolt. I decided this would also be a good time to build some new front engine mounts. I had been using some crude mounts and hockey pucks. The hockey pucks are not very forgiving and transferred a lot of engine vibration through the entire car. The new mounts I built use cushion mounts. The other major change I made was swapping out the Saginaw 4 speed for a rebuilt S-10 T5 with mechanical speedometer. Here are a couple pictures that I took. Sorry for the crappy quality cell phone pics.
IT'S ALIVE!!!! Bringing this awesome thread back from the dead. Inliners stand up! OK, enough of the dramatics, I actually have a legit question. Has anyone on here actually used the 270 GMC rods in their 261? I'm working on one now that I had intended on using the Buick V6 pistons in, which the piston uses a .940 press fit pin. The GMC 270 rod is a .990 floating pin. I have read Pats write up on here and have also picked Tom Langdon's brain a bit on the issue. The rods that Tom used were the GMC 302 rods that have 1.05" pin bores and can be bushed with (press fit) steel sleeves. If using the 270 rod, the shims would be too thin to do it this same way. I was hoping someone on here had actual experience with this. I'm assuming that I can simply bore out the 270 rod to the size of 1.05 then shim as Tom did but wouldn't want to go thru with it off only an assumption. I already have the rods and pistons so if possible would like to use them. Otherwise, if any of you have a good set of 302 rods send me a PM. Thanks for any help KK
"If" your 270 rods have enough meat at the small end (I've not compared 302/270 rods for similarity) to allow boring out .060", then I do not see why you couldn't go that route and use the same bushings Tom suggested. I used a set of 302 Jimmy rods when I built the 261 shown in my avatar. I also used a steel sleeve along with a bronze bushing to reduce to .944", for full floating pins that my Ross pistons were set up for. Nice thing about the 302 rods is the beams are drilled for pressure oiling of the pins. Not sure if the 270 rods are the same, but if you're using pressed pins, it's a mute point.
I would just get a hold of Tom http://www.langdonsstovebolt.com/ He has forgotten more than most know. Neal,
Here is an old thread from the Inliners site that may have something. CNC Dude there and here too I think would be someone to contact. He is in the process of writing some books and the GMC rods in a 261 is covered I think. Also could you have the pin bore in the piston honed for the GMC pin? http://www.inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=64264&page=1
Six Ball's suggestion of re-sizing your Buick piston's pin bores to fit the GMC's .990 size is a good possibility as well, if they have a generous pin boss. I was thinking about modifying only the GMC rods, since you'll be machining them anyway to narrow the big ends to match your Chevy rod journal width, but fact is, you'll probably be re-cutting your Buick piston's valve relief anyway, so they may not stay stock either. That's a great thread on Inliners, BTW.
Thanks for the insight fellas. Definitely some things to consider. I'll have to take it to my machinist and see what he says. He's slow like most good ones so it may be a while but, I'll post the outcome whenever he gets around to working on it.
All GMC rods will interchange(by sets) from 228-302. Stroke differences were dealt with in piston pin height except for 270 and 302 which had taller decks. There were two bearing types but only difference in retaining slot width but I don't know if the little end was different or just had a bigger hole. The only rods I have out right now are 302 and nothing to compare them to.
I've had a few people PM me about the one piece 'Powerstroke' rear main seal the I have in my 261. The seal part number is CR-38649. You'll need to have the machine shop machine a counterbore in the rear of the block that is 4.751" in diameter and .375" deep. There was an article in Engine Builder magazine the outlined the procedure. The article a was called "Old Iron: Sealing Stovebolt Chevy Engines".
Wrenchbender, Thanks for the update on this! I am planning on taking my 261 to the machine shop next week to be worked over for my new internals. I think that this will be a real improvement and alleviate the leak problem. Thanks again, Joe
I have read that the 270 and 302 rods were the same up until 56 or 57. That's when the 302 rods were fitted with the larger wrist pins of the story is correct. Wrenchbender thanks for posting the numbers on the one piece seal. I had been told what seal to purchase from others but that's as far as the discussion could go with certainty.
Here is the full Engine Builder article on the Powerstroke one-piece rear main seal installation. Sorry about the poor quality, I had printed the article off as a reference for when I machined my block. This is a scan of the printed document. The bottom picture is a shot of my 261 rear main after reassembly and prior to installation of the seal. Note the drain hole at the bottom of the cap, inside the new seal counterbore. This hole is to allow residual oil at the seal to drain back into the pan. Phil
Phil, What was the cost of machining when you had it done? Was the shop you used ok with what you asked them to do? Obviously you felt confident with them performing the task and it appears that it worked out ok for you.
The seal works great my dad came up with this replacement back in the 90s. He got tired of the rope seals leaking and the two piece viton seals from the late 235/261 engines. The seal will work on all Chevy's back to 1941. He has also built a couple 261s with GMC rods. He cut the large end down to 235/261 widths and bushed the small end to forged std pistons from a 292 ford v8. The block needed to be decked 0.125" and bored to ~ 0.080" over. Worked great. A package like this with a warmed over 848 head and you got an real engine.
Thanks for sharing the info. I am going in a similar direction without the 302 rods. 0.080 over, deck the block, deck the 848 head, + peppy cam and a multiple carb. set up.
oldwagonlover, I am an automotive machinist by trade. I did the work myself. At the time, i was running an engine machine shop. Realistically, to farm the work out, youd be looking at $100-200, maybe less. It will all depend on the experience level of the shop and how adventurous they are.
This is a little off topic: I am in need of a 58-62 261 oil filter assembly Full flow oil filter Uses same canister as V8 See photos I have posted this in the wanted section as well. Thank-You Robert J. Palmer
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