Thread: Sleeve block back to standard bore, what do you think?

Tweet

What do you think about a sleeved block? I'm about to sleeve a 400 back to standard for my '35 Chevrolet. I'd like to have a 400 to get away from the sea of 350's at the show so I picked up a few 400's and every one I come across has been already bored or need to be at least. .030 over. So I picke up 8 sleeves and I'm going to bore one back to standard. A lot of people don't like to go past .030 because of heat issues, but I'm not sure if sleeves affect the temperature or not. I can either go standard or go ahead with .030 while i'm boreing and buying pistons and make it a 406. I'd rather go with the 406 but I've got the chance to go standard and my major concern is heat. Give me you r thoughts please...Thanks

I wouldn't. One or two sleeves in a block is usually no problem, but when you sleeve the whole block your diminishing the structural integrity. The cylinders are anchored at the top and bottom of the block, the rest is water jacket. So, when you bore the block to add a sleeve your thinning out the original material that holds it all together. Small block Chevy blocks aren't the strongest in the world to start with and putting in eight sleeves would really reduce the strength.

Just my opinion.

How would filling the block with block rock , would this help hold it together? Not filling for racing just a 1/4" fill??

Get a Dart SHP block

There are a few real engine guys on this site, and some of them sound like they do in fact know what they are talking about. There opinions should carry more weight than mine thats for sure, but here is another opinion.

I wanted to get away from the regular small block chevy for a couple of projects that I have under way. I have always found the 348/409 engines to have a cool look. These are both street cars first so the performance wasn't the number one thing. I found and purchased two 348 and one 409 engine for these cars. All three of these engines needed building, but they cleaned up at .030 or .060 so no problem. But in researching the 409 it was interesting to discover that many, many 409's are sleaved and I mean all eight cylinders. Many of these 409's are in drag and street cars and they seem to be providing very good performance as well as service.

Of course the 409 is a relatively rare block and if you want to save one you do what you have to do. Also if you check the all aluminum blocks have eight sleaves as well, and it for sure doesn't seem to hurt or bother them.

I don't have a clue weather it would be more cost efficent to find another block, but sleaving may not be such a bad deal after all. MAYBE!!

RS

If, and a pretty big IF---the block is rare, hard to get, nothing else available, then sleeving all 8 cylinders is maybe the only option--I once sleeved one of our 392 hemis in all eight holes just to find out if it would work--we named it Metullsa??(snake headed goddess?)

We used it just as a qualifying engine at the drag races so we could go into the first round with a fresh motor---when we worked on it , the sleeves were so loose that they would go up and down with the pistons as we put it together or took it apart.

But for a small block chev guy wanting the bigger bore of the 400----4.125, Dart has the SHP that comes .010 under that to finish hone to 4.125 or of course go bigger, and they are reasonably priced

ok thanks guys. I've had a 350 in this car around 15 years now and I can't tell you the times I've said "it's a 350" and the next thing you know there's nobody standing there to talk to. This car is done and I've got other cars I'm trying to build so a complete under hood makeover isn't really my intention here, I'd like to replace the engine with another small block other than a 350. A 327 might be nice but probably too small for my sportsman II heads, 383 is just a 350 on steroids and is starting to be as common as the 350 even though I am leaning a little in that direction. And, I'm having a hard time putting my hands on a 400, which will probably run hot anyway, LOL. So I don't know what I'm going to do at this point. Thanks guys.

Originally Posted by 35chevy

ok thanks guys. I've had a 350 in this car around 15 years now and I can't tell you the times I've said "it's a 350" and the next thing you know there's nobody standing there to talk to. This car is done and I've got other cars I'm trying to build so a complete under hood makeover isn't really my intention here, I'd like to replace the engine with another small block other than a 350. A 327 might be nice but probably too small for my sportsman II heads, 383 is just a 350 on steroids and is starting to be as common as the 350 even though I am leaning a little in that direction. And, I'm having a hard time putting my hands on a 400, which will probably run hot anyway, LOL. So I don't know what I'm going to do at this point. Thanks guys.

That seems like a lot of work just so you can say you don't have a 350, no offense meant. Honestly a small block Chevy is a small block Chevy unless you do something exotic with it. A 400 is gonna look just like a 350/327/383/377/283 etc unless people read your sign or talk with you. If you have a decent 350, why not make it unique with some sort of Fuel injection, forced induction or some other unique induction system. Your situation was one of my motivators to go to my LS1. I had a belly button 350 and even with unique "Studebaker" valve covers it still was "just another 350". I love the LS1, it runs great, gets good mileage and definitely falls into the unique category in my car. Though they are getting more common. still don't see them in every car.

my two cents

good luck with your project

Pat

That seems like a lot of work just so you can say you don't have a 350, no offense meant. Honestly a small block Chevy is a small block Chevy unless you do something exotic with it.

No offense taken....I've got to change the engine anyway, so the work doesn't matter.

How much is a running 400 worth. I have two in mccomb MS about 350 miles away, one is a 76 impala motor still stock with a fairly new crank, it was running but has been sitting in a shed for 19 yrs. The other is in my 68 camaro, It came out of a 77 4x4, don't know about it's bore, i'd have to (keep) the heads (69-70 camel hump with acc holes) It runs, I use it to move the camaro about once a year. I am evintually going to disassemble (to inspect) both of these and get rid of one of them.

Originally Posted by 35chevy

What do you think about a sleeved block? I'm about to sleeve a 400 back to standard for my '35 Chevrolet. I'd like to have a 400 to get away from the sea of 350's at the show so I picked up a few 400's

I see geezers point there. My thought is that after you put the 400 in its going to look exactly like a 350 anyway. Only a seasoned veteran would be able to look and maybe tell its not. Just tell everyone its a 400, or go Big Block.

Keep in mind those racing aluminum blocks with eight sleeves were built for sleeves. They have solid support top to bottom before the sleeves are put in. They don't have to be bored oversize for the sleeve.

Geezer2, I hear you man, and I am certainly not an authority on this subject. As Jerry says on the "RARE" block this is an option and that may very well be the only time. I'm saying it's an option and nothing else. But you know what I'm glad that it is an option.

RS

Originally Posted by Hombre259

Geezer2, I hear you man, and I am certainly not an authority on this subject.

RS

i AM I AM THE SLEEVE KING OR... KING OF THE SLEEVES

I had my 400 bored .030, with 64cc heads with clean up cut on them. I had it in my '68 El Camino with a 6 cyl rad with a th350 tranny cooled by the in rad cooler. It never got more than 210 when it was 100 degs out, at a stop light. I also didn't have a fan shroud

Pat