Rockers ( oh its WORSE) assembly.

[Musicman]

Here's a good compression calculator for you mally69 : http://rosspistons.com/calculator.php

Mike

[defiance]

Just curious ... Why'd you decide to rebore and replace pistons rather than sleeve?

[mally69]

Here's a good compression calculator for you mally69 : http://rosspistons.com/calculator.php

Mike

Hey, thanks. I am going to do some piston  investigating now.. 

Just curious ... Why'd you decide to rebore and replace pistons rather than sleeve?

Well, becuase the cylinder right next to it which would be #4 has some pretty good size scratches from when the spark plug broke on me a few months back. the whole center of the plug broke loose.

[defiance]

Ouch - gotcha.

[Steve P.]

Mally, what you need is a piston with a flattop & valve reliefs and a 2.065 compression height which will put you close to zero deck. If the block is blueprint spec (10.725 deckheight) the pistons should be approx .020 in the hole.....then you have the block squared up and milled to achieve the zero deck (piston flush w/deck surface) to build up the compression and establish the quench zone. 

The stock rods use a pressed pin so if you go with an aftermarket piston like a Ross or Diamond you need to bush the rods for floating pins. The 2355 pistons are a press fit like the 2295's that are in there now. They weigh almost the same as well so rebalancing will be easy...and i would hav the rotating assembly rebalanced while it's apart. You should also have the rods checked over and ARP rod bolts installed if you haven't allready done that.   



Ron (in Vegas using Steve P's user account  )

[Musicman]

Hey mally69... don't you have a 4.25 stroke to go along with that 4.36 bore and 84 cc chamber?

[mally69]

Hey mally69... don't you have a 4.25 stroke to go along with that 4.36 bore and 84 cc chamber?

Nope  this is my 440 that I have been running for about 3 years that has the stealth heads on it. My 512 stroker has a 4.25 stroke with 75cc indy heads.

Mally, what you need is a piston with a flattop & valve reliefs and a 2.065 compression height which will put you close to zero deck. If the block is blueprint spec (10.725 deckheight) the pistons should be approx .020 in the hole.....then you have the block squared up and milled to achieve the zero deck (piston flush w/deck surface) to build up the compression and establish the quench zone.

The stock rods use a pressed pin so if you go with an aftermarket piston like a Ross or Diamond you need to bush the rods for floating pins. The 2355 pistons are a press fit like the 2295's that are in there now. They weigh almost the same as well so rebalancing will be easy...and i would hav the rotating assembly rebalanced while it's apart. You should also have the rods checked over and ARP rod bolts installed if you haven't allready done that.



Ron (in Vegas using Steve P's user account )

Perfect, this is what I am going to do  .... The 2355's are 2.061 Compression distance, so its close to the 2.065 like you mentioned..  Oh yea not to high jack my own post but, hows thing's going down there in vegas.

[Musicman]

Nope   this is my 440 that I have been running for about 3 years that has the stealth heads on it. My 512 stroker has a 4.25 stroke with 75cc indy heads.

Sorry, my mistake... I thought both of them were stroked 

Mike

[NorwayCharger]

Mally,

The crane golds are really descent rockers when used in the right application (NO roller cam spring pressures) and your valvetrain is allready set up for an adjustable rocker arm at this point. The Comp 501 is a slow (Ramp) lazy grind so now is the time to make the move to a better rocker arm. The Crane 1.6 Gold rockers is what i would use for increased valve action and more high lift area with that cam profile.

In a nutshell, swapping to the 1.6's would be like swapping in a better cam and upgrading the rocker arms at the same time. It's time to make something positive out of this negative situation. 



Ron

And maybe gain 15-20 hp?

[mally69]

Mally,

The crane golds are really descent rockers when used in the right application (NO roller cam spring pressures) and your valvetrain is allready set up for an adjustable rocker arm at this point. The Comp 501 is a slow (Ramp) lazy grind so now is the time to make the move to a better rocker arm. The Crane 1.6 Gold rockers is what i would use for increased valve action and more high lift area with that cam profile.

In a nutshell, swapping to the 1.6's would be like swapping in a better cam and upgrading the rocker arms at the same time. It's time to make something positive out of this negative situation. 



Ron

And maybe gain 15-20 hp?

really, would i gain that much??     

[blown71cuda]

I know its late but good choice on the rockers.  I found the non roller fulcrum work the best.  I had nothing but problems with harland sharps.  would break  all the time.  Switched to a set of indy rockers and never had a problem.  The indy rockers are brass bushed but i also have a high lift roller cam with a high rate spring.   It is a pump gas street car also but good luck to you i understand what you are going through.  Paul

[Ghoste]

I don't think I've ever heard of anyone having Harland Sharps "break all the time".  That would get expensive in a hurry.

[blown71cuda]

This is what would happen to the harland sharp.  I could not figure it out there is not a mark on them.

[Ghoste]

Wow, did they offer any insight?

[blown71cuda]

im sorry that i never bothered to contact them.  But i did have a two different engine builders check the geometry and all. I got the same answers that every thing looks correct.  I switched to the Indy rockers and have not had a problem in 3 years.

[Blakcharger440]

This is what would happen to the harland sharp.  I could not figure it out there is not a mark on them.

WoW! I am going with the Crane golds also.

[KillerBee]

Have you mocked up the Crane rockers on the engine/heads with the pushrods installed yet?
I'm curious if the 1.6 rockers cause any pushrod clearance issues with the pushrods rubbing on the heads.

[mally69]

Have you mocked up the Crane rockers on the engine/heads with the pushrods installed yet?
I'm curious if the 1.6 rockers cause any pushrod clearance issues with the pushrods rubbing on the heads.

Not yet I havent, but I will let you guys know what I find out. I was thinking the same thing I guess ill find out soon..

[mally69]

Ok I had to bore my block 60 over. And I also am going to get speedpro 2266 flattop pistons with no valve reliefs. Should get me to 10.7 compression with the piston 5 in the hole and a 40 thousandths gasket.

[BLAM]

Wow 60 over.  Have you considered a sonic check of the bore wall thickness yet?  My 512 is 50 over but I had my bores checked first.  If I had gone 60 over I think at least half of my thrust side bores would have been too thin for a safe build.

[mally69]

Well, here is my options. Nothing has been bored to 60 YET. It will clear up at 50 over we beleive.
1. Bore all cylinders 60 over.
2. Bore all cylinders 40 over and sleave the one that had the accident.
3. Bore all cylinders to 50 over and get custom size  pistons.

Help me decide what the best route would be. I know sleaving a cylinder isn't the best thing to do, Nor is boring it 60 over, and custom pistons are costly and take time to get. All options are kinda sucky I just want to hear everyone's opinion.

[Musicman]

I would consider the 60 over myself, since it's not usually a problem, but I would have the block checked first, just as I would with any block that's headed for the machine shop.

[FLG]

Mally,

Is this car numbers matching? Have you considered just starting with a fresh block, Boring it to the size of your current pistons and just moving everything over?

[mally69]

Actually I turned my spare block into a 512.. Also its not a matching numbers block either.

[FLG]

I would see how much you can get a new block for and the cost of the machine work and compare it to the cost of this block being sonic tested, bored, the one cylinder sleeved and/or the cost of custom pistons. . I think it would be a much better choice to just bore another block and move everything over..that way you never have to worry about anything. And its probably going to be cheaper, if not the same price.