Inliners International
Posted By: MiamiKeith 261 rebuild hit a snag - 01/24/18 12:52 PM
Am in the middle of a rebuild on a '62 261. Just got a call from machine shop. He says he's not comfortable with reusing the rods. Engine was already .060 over with a couple rebuilds on it. Rods have been previously reconditioned and not very well. Hoping someone may have or know of a set somewhere. Any help appreciated.
Posted By: Beater of the Pack Re: 261 rebuild hit a snag - 01/24/18 02:27 PM
If you are going to any performance level you would be well served to take the step to GMC rods. There is some machine work involved but you need new rods any way. GMC rods are probably easier to find and cheaper than 261 rods. There is at least one thread here telling what must be done.
Posted By: MiamiKeith Re: 261 rebuild hit a snag - 01/24/18 02:58 PM
Hi Beater. Thanks for the reply. Tried searching for that thread. Couldn't find it.
Posted By: panic Re: 261 rebuild hit a snag - 01/24/18 03:43 PM
Just a heads up: I agree that the GMC rod is a far better basis for a performance build, but they require non-factory pistons with a shorter compression distance due to 3/16" greater C-C length.
Posted By: stock49 Re: 261 rebuild hit a snag - 01/24/18 06:27 PM
Originally Posted By: MiamiKeith
Hi Beater. Thanks for the reply. Tried searching for that thread. Couldn't find it.


Hi MiamiKeith . . . just a quick hint - Google searches this site better then the local BB search routine.

All one needs to do is use the 'site' keyword along with the search terms - in this case "site:inliners.org GMC rods in a 261"

regards,
stock49
Posted By: CNC-Dude #5585 Re: 261 rebuild hit a snag - 01/24/18 07:05 PM
Since his block is already setup for his oversize pistons, 261 rods are going to be his best and most economical solution.
Posted By: tlowe #1716 Re: 261 rebuild hit a snag - 01/24/18 07:22 PM
After a quick look on Ebay , found these. He is a inliner, I think asking a bit much but could be wrong.
261 rods
Posted By: CNC-Dude #5585 Re: 261 rebuild hit a snag - 01/24/18 07:46 PM
That does seem a bit high and they still need to be reconditioned likely as well.
Posted By: MiamiKeith Re: 261 rebuild hit a snag - 01/24/18 08:02 PM
Thanks everyone. Advice much appreciated!!!
Posted By: Beater of the Pack Re: 261 rebuild hit a snag - 01/24/18 11:21 PM
It's mentioned here.
LINK
Posted By: mdonohue05 Re: 261 rebuild hit a snag - 01/24/18 11:57 PM
You asked this question over at stovebolt too. Those rods would have to be really really beat up to not be rebuildable. The rods need to be magnafluxed to make sure they are not cracked. Have them checked for straightness. Then get some big block Chevy rod bolts. New Rod bolts for a 261 are like non-existent. Have the caps machined down, install the rod bolts. Resize the big end back to specification. Contour the rod bolts so they are shaped at the head like a 261 rod bolt (make a template if you want so you can check the work.). When the machine work is all finished, balance the set.

The GMC rod conversion is more work then most know. Not many have actually done the conversion. I have. The rods need narrowing in addition to a good rebuild. Rod bolts are the same issue, they need massaging. The gmc bearings need to be chamfered or in my case, had to be narrowed. The cam has to be clearanced between the lobes to clear the rod bolts and if you do it after the cam is final ground, you have to send it back because all that hand work bends and twists the can and it has to be refinished. This swap does need custom pistons. My motor is pretty modified and will get to 6000 rpm in a snap. That is why I did the gmc rod conversion. Unless you are planning on really getting on your motor, the 261 rods will be fine, at least in my humble opinion.

The thread for the conversion is mine. When you read through it you will see what a lot of work it was.

https://www.inliners.org/ubbthreads/ubbthreads.php?ubb=showflat&Number=90677&page=1

Go back to your machinest and ask him what it is about those rods he is concerned about. A couple of builds on the rods should not be that much of an issue for a good machinest.

This is my son driving my 57. It’s a street motor so not a race motor and he was driving it (and going down a race track) in dad’s car for the very first time so dad (me) told him to take it easy. Like I said, unless you intend to really hammer your motor, use the 261 rods.

https://youtu.be/lMVz66tyrKQ
Posted By: MiamiKeith Re: 261 rebuild hit a snag - 01/25/18 10:19 AM
Thanks to everyone that replied. Great info and VERY much appreciated. Engine will be for street use although I may be temped to get on it occasionally grin

Went to shop yesterday and looked at rods with machinist. Problems noted were several and maybe they are OK for a street rebuild. I'm not knowledgeable enough to know.

Caps are slightly crooked on the inner surface. If you run your finger inside you can feel a definite lip. Not a smooth joint. Also the cap ends are a bit out of round, already oversize and different widths. He's worried about uneven wear and excessive lateral movement on the crank.

A couple also have some twist to them.

The machine shop is pretty well know in the old car hobby locally. Not sure how many 216/235/261's he's done but it's several. His shop is one of the only ones in town that works on the old stuff. Lot's of engines from the 20's to 70's. His rebuilds are known for running smooth and quiet and lasting.
Posted By: panic Re: 261 rebuild hit a snag - 01/25/18 09:52 PM
The cap makes me nervous, suggests a low quality rebuild in the past.
Rods can be straightened, the question is how well.
I would find original (un-rebuilt) cores.
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