What pistons for .020 over rebuild

[rockjeep73]

As the title says, what pistons do I want to run in a .020 over 12 valve. Motor will be in the 600-700 HP range, single turbo + nitrous.

I was planning on running .020 over coated 370 marine pistons but I read in another thread that the .020 over pistons were not as strong as the standard ones. Will they be OK at only 600-700hp? THe reason I was going to go with the marines was because of the drop in compression and the larger bowl for the ability to run more timing.

Let me know what my options are.

1. Different Cummins marine

2. Standard Cummins

3. Mahle

I was wanting to stay with a Cummins piston to keep the cost down.

Also, how much piston to wall clearance?

Thanks
Cory

[rockjeep73]

Anyone have any input on this.

Reading from another thread it seems like the Cummins .020 over 96-97 215hp pistons would be the best choice. With these pistons how much would have to be milled off to drop the compression to about 15.5

Any input on the Mahle's? I was trying to stay away from the mahle 155's due to the price.

How much timing can you run on with the standard bowl pistons vs. the marines?

And how much piston to wall clearance is recommended?

The block is going to the machine shop tomorrow and I would like to get some pistons ordered as soon as possible.

Thanks for the help.
Cory

[Joker12valve]

Give garret a call at pure diesel power 715 498 0707 he is always rebuilding some thing.

[triton]

unless your truck is a race/pull truck only, you want to stay away from Arias or Mahle pistons. They're too soft for daily driving or distance driving. They're meant for race applications. Besides... they're expensive.

Cummins pistons are some of the strongest out there and are a good choice. I used them, had them shaved along with a ceramic coat to the top and teflon skirts.

[OT-OF-Here]

Just sleeve it to stock and run oem pistons and get them coated.

[rockjeep73]

Well the truck is a dedicated drag race truck and wont be seeing any street time. The main reason I was trying to stay away from arias or mahle was because of the price tag.

Right now it seems like the 215 cummins pistons mentioned above are the best choice. Now I just need to find out the specifics, such as piston to wall clearance, how much to mill the pistons and what compression ratio, ring end gap?

[DieselDiva]

I just ordered custom Ross pistons for my pulling truck. They told me not to have them ceramic coated. They only recommended the hard anodized coating, as ceramic makes the pistons "too" indestructable & will reflect heat into the cylinder head and valves.

Most of the large shops (Scheids & Haisleys) only use the hard anodizing as well, on forged pistons.

[Diesel Freak]

Anodizing good

Ceramic bad


Ceramic will flake off as the piston expands...it can mess up exhaust valves etc.

[triton]

Originally Posted by Diesel Freak

Anodizing good

Ceramic bad


Ceramic will flake off as the piston expands...it can mess up exhaust valves etc.

I've heard this said but, had mine done anyway. If you were to talk to Swain coatings they guarantee it not to flake. Also any flaking that may happen would be so small it would just blow right threw which I figured but, they claim it will not happen. I really think it depends on the type of coating used and the way it's applied. Some are very cheap and poorly done and others ( Swains ) aren't. Ya get what ya pay for !

I also had the skirt tefloned. I've ran it pretty hard since it was done but, don't have lots of miles on them. So far.... I've had no problem.

My truck isn't a pulling truck like being talked about here but it see enough high temps to give the ceramic a work out.