Well I am at it again. I am trying to put together and build a 427+ ci. Please tell me if this has been attempted before. When I was younger a friends dad raced small block chevy in the mud bogs one race was 1/8 mile drag and the other was slolim course since then they have moved away. But I remember that he ran a dry block of course no rad or waterpump and used a filler in the block and heads that was lite weight he said it was to lighten the vehicle. Years later I am thinking that I could take a 105 block, bore it out to fit 427 sleeves (about $900.). and there is a company that will sell the side bolt main caps for about $350. if needed, then buy a scat 428+ crank for the stroke and special piston rod combo and fill the block with this filler ( when I have asked machine shops if I could bore so much away they all said that there would not be enough material left between top of block and bottom to support the cylinders and top deck.). I am planing on only running this engine a 1/4 mile track down then off. Does this have a great potential for a large amount of HP for a short distance but at an affordable cost I have looked into the new 427 blocks ect to much for me. thanks for reading my thoughts and I appreciate your input thanks

 

This has been done but I can't remember which site did it. It really isn't feasable and will cost quite a bit. They had no cylinder wall left when they got done boring to 4.23". You can get almost as much out of a 390 or 428 with some heavily ported heads as you can a 427 nowadays. You can stroke a 390 out pretty far with the stoker cranks that are available at www.flatlanderracing.com . Go to their site and look at the kits available. They also sell ported edelbrock heads with improved hardware.

 

[updated:LAST EDITED ON 08-Jan-03 AT 01:39 AM (EST)]If I was to use the larger 428 stroke crank because there are three strokes offered that is what I ment by the + sign and used the 427 piston bore you would end up with alot of cubes maybe 440+. I am also interested what different combo's you could use with a 428/410 crank in a 390 block I know you can use a 390 piston if you take off about .100 off the top. How about using a 352 or 360 piston or the shorter rods with 390 pistons. About 15 years ago I worked at a NAPA store and the rebuilder that we used made what they called a 360 special, witch started with a 360 block and bored it out to a 352 .080 piston and gained compression and power. My first engine I rebuilt was a 352 that I bored out .080 in a 62 Galaqie at I have beaten many SBC corvettes nova's and camaro's even blew away a 428 CJ I won't say what is was in at this forrum though. Question what part of this other other than the sleeves would be so expensive I didn't think that $900. for the larger bore versus a new 427 block at $3000 was so bad especially if you could come up with over 440 cubes. Could you please tell me what kind of problems that I would or could have in trying this project? thanks

 

>About 15 years ago I worked at a
>NAPA store and the rebuilder that we used made what they
>called a 360 special, witch started with a 360 block and
>bored it out to a 352 .080 piston and gained compression and
>power.

352= 4.00" bore 3.5" stroke
360= 4.05" bore 3.5" stroke
390= 4.05" bore 3.78" stroke

An .080 over 352 = .030 over 360 and a .030 over 390 as far as bore sizes go.
In order to get 427 sized sleeves in a 390 block, you're going to remove most of the existing cylinder wall. When you remove the cylinder walls, what ties the block together in the middle? Nothing. Your cylinder liners are probably an interference fit, possibly helped by some epoxy. The block will flex, the middle three mains will have considerably less vertical support. I'd be surprised if you manage a single full power 5,500 rpm pass with the engine intact at the finish line.
I don't know about the feasibility of adding cross-bolted main caps to a 390 block. Doesn't the block need to have the bosses for those caps?
A dual quad 427 had 425hp, right? With Edelbrock headsand a good intake, a bit more compression, better rocker arms, shafts, and supports, and the right cam, 425hp should be an easy number for a .030 over 390, in my opinion.

 

Lets not forget, the 427 cylinder walls were not round on the outside like most other engines. THey were "cloverleafed" which basically meat they had four corners on the outside. You won't have this with sleeves. Also as a side note. A 390 will make every bit as much power as a 427 with edel heads. Cubic inches do not make horsepower. Sometimes less cubes with the same setup will give you more horsepower. Displacement makes torque and HP at a lower RPM. You could say it only offers a potential for Horsepower.

 

I got a 472 cube motor that has a 3.79 stroke it revs!
plus it'll pull the socks off my 01 psdeisel, thats stock. I
think you have a very good idea. With that kinda cubes and
the short stroke you'll get the best of both worlds.
Most 400+ cubers have to run 4 inches stroke atleast to get their displacement.

Dory

 

[updated:LAST EDITED ON 08-Jan-03 AT 08:47 PM (EST)] OK guys we are off to a good start now that I have got you thinking lets continue this conversation. Remember my story about the SBC mud bog Jeep of my friends dad that ran a dry block with filler in it this would tie the top block and bottom block and sleeves all together even if you removed all of the cylinder sleeve, in fact I beleive that this would be a great setup with aluminum heads and run alcohol (to run cooler), not only for the weight but this would stop most of the block expansion and the block to heads would seal better.
About the side bolt main caps, the company says that a qualified machine shop can machine the block to accept the main caps and spacers and of course line bore journals.
Back to the 105 390 block. So if I sleeved the block filled the block with Moroso filler compound(stated that it is for helping very thin cylinder walls from cracking and improves ring seal by keeping the cylinders round) ran HP Edelbrock aluminum heads and intake with liwuid filled heads and intake and then ran alcohol to keep temperatures down. Run a 425. (aprox) piston and about the same stroke (as close to 425. as poss) and the longest rod possible to keep the rod angle high (when this is done the small end of rod is way high in the piston so that when it is fired the rod is at an angle faster so that the down pressure pushes the crank journal down eisier) And yes you are correct more cubes = more pottential power.
wich can be put to use. Do you guys follow what I am trying to say here I know that it is a mouth full but I have spent a lot of time thinking about this just so I can go from one end of the racetrack to the other as fast as possible thanks guys.

 

As for as the .080 352 pistons in a 360 goes, the 352 (65-67)Deck clearance is .055 the 360 (68-76) is .104 that is .049 tighter. the compression height on the same 352 is 1.825 the 360 is 1.776 . both having the same deck height. If you could use the 60 352-4V piston it has .030 deck clearance. All I know is that it was a better runing engine than the originall 360. When I rebuilt my 352 I used flat top pistons and there were some 360 pistons laying around and you could eisily notice the compression height difference in the two.

 

Hard Block will work for short burst down the dragstrip but I have never heard of running it around in the mud. I have also heard of people using hard block and only filling the block half way up which would allow some cooling. Still going to be hot in the cylinder. I dunno man. You are really stretching your luck. Unless you are looking for a 1000HP nitro drag engine I would stick with a 390. The power differnce is minimal compared to the work involved.

 

Even if you fill block before you bore and sleeve it will never hold together. It miht last a weekend or even 1/2 a drag season. But, the oney and benifits will weigh equally. You will be better of witha stroked 390 with other hop up goodies to get your mojo going.

Scotty

 

for a whoooooooole lot less money, you can buy a used 429/460 that will have more hp the second you drop it in.

david

 

>for a whoooooooole lot less money, you can buy a used
>429/460 that will have more hp the second you drop it in.
>
>david

Have you ever try'd dropping a 429/460 motor in a 67 Fairlane Ranchero this truck uses the mustang Fairlane front end set up. Let me know

 

>for a whoooooooole lot less money, you can buy a used
>429/460 that will have more hp the second you drop it in.
>
>david


David, I'm sure you mean well, but if I wanted to hear talk like that, I'd be in the 429/460 forum. Let's keep it clean around here.
:-) He's better off with a 390 anyway. They'll last longer. Heck, I'm trying to swap my 460/C6 combo (bone stock and tired) for a similar 390/C6 setup, but nobody around southwest Iowa wants a 460 either
...
Seriously though, a 390 with a fresh bore and a few good parts will make 425 ponies easy, without spending a rediculous amount of money boring and sleeving. And if you've got some cash burning a hole in yer pocket, buy a stroker crank. More bang for the buck.
Just my opinion