Sleeving a Y Block for 344 CID?

Sleeving a Y Block for 344 CID?

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By grovedawg - 15 Years Ago

I'm still in the planning stages of my build, and what Tim's done with his FED Project as got me thinking a little bit outside the parameters of a "normal" y block rebuild. Initially I was planning on building a wicked little motor by boring my 272 to a 292 and running performance parts on her.

Now I'm wondering what it would take to sleeve my motor, and run with a 4 inch bore, and the stock 312 crank stroke. It would take the displacement up to 344. I just have never "planned" a project like this before and really would appreciate a little sage wisdom.

My questions would be what pistons could I use? 302's are a 4 inch piston. Would that be an option?

What about rods? I'd prefer to find something that doesn't have to be custom built for boo-koo bucks. Any ideas on what might work?

I want to make sure the rod length works with DH, CH, and stroke to come out at about 0 deck clearance. Any suggestions or guidance would be greatly appreciated. Thanks, the Dawg

By charliemccraney - 15 Years Ago

The easiest, and most cost effective way for you to achieve your goal is to find a block which will bore to 4".

If you don't want to spend boo-koo bucks, then I think you'll need to consider other options.

To sleeve an entire V8 in my area was about $1200 3 years ago - that won't equate to $1200 worth of performance. The likelihood that you find parts that will fall together is slim. The only rods which will "bolt on" to a Y crank are Y rods. Any other option will require custom machining of the crank and/or rods - may as well offset grind the crank for the extra cubes in this case. To keep the crank/rod costs low, you'll need to find a piston which is taller than the deck but not so tall that it can't be cut to fit and fits, or can be modified to fit, the stock rod. And there still may be other issues with the piston, such as counterweight interference, that will have to be dealt with. The one thing good about the 4" bore is that the selection of pistons will be practically limitless.

I think the cost of sleeving can be better applied elsewhere, like stroking, porting, finding out how big you can bore it and custom order that size, etc.

By grovedawg - 15 Years Ago

I was planning on turning the mains on the crank. I have thought about offset grinding th crank and running a stock 292 piston, but that puts displacement at about the 308-309 ball park. So, offset grinding the rod journals might add a few additional cubes over standard rod journals on a 312 crank. I was also thinking about the possibility of turning the rod journals down to chevy rods (I know that might be blasphemous, but it might be a solution).

Are you basically saying that the additional 1-1200 cost of sleeving and boring to gain 30-35 additional cubic inches won't pay off? I'm also planning on porting my g heads, using oversize intake and exhaust valves (2.02 intake and 1.80 exhaust- I think those are the sizes).

Maybe I'm just curious as to what Tim's set up was, or if anyone has done something similar. I know with engines anything is (theoretically) possible with a big enogh budget. I don't really have a "master" engine builder to help answer my crazy questions when they pop in my head. But it sounded fun (as if rebuilding a quarky y block isn't already enough fun.

Thanks for the response. Any other suggestions are appreciated. The Dawg.

By grovedawg - 15 Years Ago

Charlie, I also wanted to say I have the 312 crank that I'm planning on using, I've sonic tested my block and it will "comfotably" go out to a standard 292, with an average wall thickness of about .167 of an inch. I don't know if that helps.

By charliemccraney - 15 Years Ago

I don't think Chevy rods are blasphemous. Besides, you probably won't actually use Chevy rods. It'll probably be an aftermarket rod designed to fit a Chevy - by the time a set of stock rods is refurbished, you probably could have bought a new set.

It's not so much that it won't pay off as it's just not the best bang for the buck. Within that price range, you can find several 292 blocks. Without a doubt, you will find one that will comfortably bore to std 312 (or bigger, maybe 4"). In reality, you can probably find a 292 block for the price of boring the 272 to 292. There are just more cost effective ways to achieve the same goal.

I'm all for using original stuff, if that's what you're trying to do with the 272 block, but if it doesn't make financial sense, I personally can't justify it. A 3.86" bore with your 312 crank offset ground to 3.60", using Chevy rods, will produce 337ci. A 3.90" bore with the same stroke is 344. The same stroke with a 4" bore, 361. If you plan to turn the journals to the Chevy spec, then it makes sense to offset grind as well, otherwise you won't gain much.

You need to determine how much you want to spend on it. If sleeving fits the budget, then by all means go for it.

There is also the potential for reliability issues. Last years intended Engine Masters entry was meant to be a 4" bore x 4" stroke combo. The block had to be sleeved to achieve the 4" bore. It didn't make it past the first dyno test session.

http://www.y-blocksforever.com/forums/Topic33114-5-1.aspx

By grovedawg - 15 Years Ago

Thanks for your posts Charlie! It seems that in your experience the better design for a Y block is to find a good 292, bore it out to a bigger diameter (within a safe margin to maintain wall thickness) and then use an offset ground crank to achieve higher displacement.

Can I ask a few more questions? What is the limit you can offset grind rod journals on a 312. I know Mummerts web site says 3.6 is the upper limits of a stroke that a block can handle without having to relieve parts/pistons/block. Can you offset grind a crank out to 3.60 safely or without welding it?

Another question. What rods can I use at that point, if I did stroke it out to a 3.60? What have you been able to use in the past?

By aussiebill - 15 Years Ago

grovedawg (5/12/2010)

DAWG, I dont think the 4" bore is a practicle way to go, by the time you bore the 292 block out to take sleeves, theres no original walls left and would or should have the sleeves brazed to the deck for support. I think ted or john have a 4'" project as i have and think keeping the block integrity is more important than the magical 4" bore. Keep on with project.

By charliemccraney - 15 Years Ago

There isn't really a formula. The 1st step is to determine just how much stroke can be gained with your crank. If it's standard, you will be able to get the most. If it's 10, 20, 30 under, you won't be able to get as much. Once that's determined, you will be able to choose the rod and piston. Since you're wanting to use off-the-shelf components, you'll have to browse catalogs until you find a combination that gets you where you need to be. If you're willing to go the custom piston route, then choose the longest rod which allows for a reasonable compression height so that nothing exotic has to be done about supporting the oil ring. I don't know where the limit is with the stroke as far as having it drop into the block without having to worry about clearancing - but really, if your considering going so far, it's no matter.

By Hoosier Hurricane - 15 Years Ago

The limit on a Y block stroke is the rod big end hitting the camshaft. Cams with smaller base circles and lobes can be ordered, and aftermarket rods for smaller journals are smaller on the outside also. Ted got a 4 inch stroke by using a special cam and Honda size rods. Still had to grind some clearance on the rod big ends.

By grovedawg - 15 Years Ago

Aussie Bill: I'm for sure not set on a 4 inch bore. I just thought it was a cool idea. But because you guys have had less than stellar experience with sleeving, and it seems there are better uses for my money to reach larger displacement I've put the idea to rest. I've got two 292 blocks in my area, one for about $150 bucks, and the other for $250. I'll probably buy the lesser expensive C1TE block and give it a good wash and magnaflux before I start going crazy.

Charlie: Where should I start shopping for aftermarket rods and pistons? I'm really that much of a newb!!! Blush

Let's say I take the 292 out to a standard 312 (practical, and feasible with almost any 292 block). So, I can still use 312 pistons, or search around for a forged pistons (maybe Ross? I'm dropping that name so you'll think I'm smart) Smile

And then off-set grind the crank out to whatever my Crank-Miester says will work. At that point where should I look for aftermarket rods?

By charliemccraney - 15 Years Ago

grovedawg (5/13/2010)

Charlie: Where should I start shopping for aftermarket rods and pistons? I'm really that much of a newb!!! Blush

Easiest, John Mummert. www.ford-y-block.com

He even has stroker kits.

If you want to do it all yourself, then first you need to determine the stroke. Once that is determined, call a piston manufacturer (like Ross) and see what minimum compression height they recommend. With that, and the stroke, you'll have an idea of the maximum rod length that will work. Use a site like Summit Racing, or Jegs to find a rod length that will work best. When you've picked the rod, order the pistons. That's how I'd do it, anyway.

By grovedawg - 15 Years Ago

Hoosier Hurricane (5/13/2010)

I don't know that I would want to take it out to 4" because of all of the ensuing work to get everything to mesh in one block. But if a 3.60" stroke has been done I'd love to know how.

312 rod lenght= 6.252"

312 stroke= 3.442"

Increasing the stroke from 3.44 to 3.6 is going to reduce the rod length down to about 6.182. Or there abouts?

By grovedawg - 15 Years Ago

Easiest, John Mummert. www.ford-y-block.com

He even has stroker kits.

If you want to do it all yourself.....

I want to buy as many parts as I can from John, because I'd love to support him. I reference his site all the time, and want to help him out for what he's done for me thus far. But a small part of me thinks buying the kit is kinda like buying a crate motor. I would love to do it on my own so that I learn what goes into the process you know?

Thanks again for all of your responses.

By mctim64 - 15 Years Ago

I tried to post earlier but the dreaded "Lock up" and I had to get to work. Anyway I just wanted to say that I wouldn't reamend sleeving a block in all eight for a 4" bore for the street. I was able to get away with it for a number of reasons not the least of which is I have a machine shop at my disposal but also I filled my block afterwards to stiffen it and it is only ment to run a few seconds at a time anyway. From what I've read it looks like you are now thinking about more stroke and that is where i think i would go with a street engine and keep the bore to a max of 3 7/8".

Here is 2/100 $ Tongue

By mctim64 - 15 Years Ago

I just want to say it took me three trys to make that last post. w00t

By Glen Henderson - 15 Years Ago

Let just say, that there is absolutely nothing wrong with buying a complete kit from Mummert or having someone like Ted or Tim build up a stroker for you. I understand wanting the hands on part of it, but unless you have access to a complete machine shop and a machinist who knows y blocks, this is one part of the build better left to the pro's. Not only are you going to spend more money and time (time is money) trying to piece something together, you are taking a big chance on having it fail completely, something as simple as one machining error could foul up the whole works.

By grovedawg - 15 Years Ago

Glen, I couldn't agree with you more! One machine error and the engine could fail. The same holds true with buying a kit from John. One machining error, and John's kit could fail. I just really like the idea of understanding everything that goes on so that I KNOW the engine. I could very easily buy John's kit and take it to my machinist and have him assemble the whole thing- but I'd prefer to try and put it together on my own. Kind of why I fix my daily driver instead of taking it to a shop.

I realize it means many trial mock ups, and a lot of questions, and possible buying the wrong parts, only to buy the right ones later- but that's kind why I signed up for this in the first place. Smile

To get my hands dirty, and maybe develop a headache or two when the crap doesn't work right!

That being said, if John reads this, I will buy as many parts from you as I can! BigGrin

I want people like John to stay in business.

By grovedawg - 15 Years Ago

mctim64 (5/13/2010)

Thanks for the insight Tim. PS, I love your FED project (The youtube start up video is AWESOME) and appreciate all the information you guys are willing to give.

By ejstith - 15 Years Ago

There's a 338 cid on Ebay for $9,800 bucks .... lol !!! I can't even imagine such a thing ..