Thoughts/Opinions on Piston Rings
 

As I continue to collect needed parts for the engine build going into my '51 Tudor, I come to the subject of piston rings. Although probably overkill, I'm going to use Ross pistons. Depending on what oversize I decide on, the availability of conventional rings, like Grant and Hastings, which I have used in the past, and the Metric ring packs that have been talked about here in the past are available. Any thoughts, opinions, etc. most welcome. If I have not mentioned something important please let me know. Thanks guys.

Re: Thoughts/Opinions on Piston Rings
 

If you decide on Ross forged pistons, expect a little noise till the engine warms up and most likely a little oil consumption due to the piston to wall clearance required, not my first choice for a street Engine, for the street there are many good options in cast pistons, Egge for one has some quality cast pistons. others here will offer their experiences.

Re: Thoughts/Opinions on Piston Rings
 

Give some thought to total seal piston rings, an over kill but good.
Lawrie

Re: Thoughts/Opinions on Piston Rings
 

RE: Ross Pistons

I definitely prefer modern metric ring packages over the old Grant/Hastings stuff.

I've used both TotalSeal rings (worked really well) and also other metric ring packs in 1.5, 1.5, 3.0 sizes. There are only certain stocking piston sizes that can be bought with metric rings. BUT, if you call their sales support crew, you can discuss your minimum bore size and then look at the available metric ring sizes and they'll make a custom piston diameter to match the rings. This is what I tend to do these days.

If you go through their sales folks (see if a guy named 'Ed' is still there - he is very helpful), you'll usually see only a small upcharge (like $40 or so) for a custom piston size.
Then you can go to places like Summit Racing and reference the Sales Engineer and have them order the right stuff for you (they'll probably call Ed) - getting the decent price from Summit (plus the up charge).

The metric rings result is less friction loss, are made from better materials (moly top ring) - no reason to NOT use them. As noted above, my resulting ring pack is usually 1.5, 1.5, 3.0 mm . . . though sometimes the top rings might be 1.2 or 1.5.

You can do a bit of research before you call them and look at common metric ring sizes that are close to what you want to bore too - then convert to inches if you need to see what sizes are available as compared to "normal" USA over bores.

Example: I have a 3.375" bore racing block that I want to put new pistons into. I looked up ring sizes and there are tons of 86 mm rings available. So, you divide 86 by 25.4 and you get the bore size in inches. The result is a 3.3858 bore . . . just .010 over my current bore. When I order pistons, it will be for 86mm rings. The block will NOT be bored until I have pistons in hand . . .

Re: Thoughts/Opinions on Piston Rings
 

Are cast pistons available with a metric ring pack? Or are you forced to use a forged piston like Ross? The application is a street motor, not racing.

Re: Thoughts/Opinions on Piston Rings
 

You'll have to talk to the piston manufacturers - to see if they offer metric ring packs and or pistons sized for common metric rings. The challenge with most manufacturers is the minute you say "custom size" or "custom anything" - you really get whacked on price.

Re: Thoughts/Opinions on Piston Rings
 

Talking to a piston manufacture is like talking to a brick wall!!

Re: Thoughts/Opinions on Piston Rings
 

Don't agree. The folks at Ross and Wiseco were extremely helpful.

Re: Thoughts/Opinions on Piston Rings
 

Agree with Bored & Stroked in every way. I also use torque plate to hone. I feel this is very important.
Cheers
Tony

Re: Thoughts/Opinions on Piston Rings
 

Do you use an aluminum or a steel torque plate? I'm going to make an aluminum one on the NC mill - as I use aluminum heads so this makes sense to me. I'll probably groove it for o-ring material as well - so I can also use it for a pressure test plate.

Re: Thoughts/Opinions on Piston Rings
 

I made my torque plate by boring the guts out of an old cast iron head.
Lawrie

Re: Thoughts/Opinions on Piston Rings
 

Back on topic "piston rings":
Seems to me that for a mild performance motor, the ideal piston/ring setup would be a hypereutectic cast piston to (minimize clearance) with a metric ring stack (less friction & better sealing) plus the compression height and dome shape to achieve proper piston/head clearance. Such pistons do not appear to be readily available. Would be nice to know otherwise.

Re: Thoughts/Opinions on Piston Rings
 

I made mine like Lawrie did. Talked to both Ross and Egge, their solution was mega dollars. Ross wanted me to buy 4 pistons for one replacement piston.

Re: Thoughts/Opinions on Piston Rings
 

Hypereutectic 3-ring pistons were offered for a while but then disappeared. Either sales were dismal or there were problems in service but either way, they are no longer on the market.

Re: Thoughts/Opinions on Piston Rings
 

I would ask my self these questions.
1. How many miles a year driven. Most Classic cars see a limited miles you don't need to build it for 100K miles. Cast pistons and standard rings will work.
2. Rpm wanted. If you are going for high rpm then forged or hyper pistons are needed.
3. Boost are you planning on blower/super charger or turbo then a high quality piston is needed.
4.Carb or injection the original fuel system washed down the cylinder wall so a good quality ring is very important.
One thing to note is a chrome molly ring set will take up to 10K miles to fully seat.
Just a few questions we ask customers at the machine shop. Don't over build.
Enginepieces

Re: Thoughts/Opinions on Piston Rings
 

Aluminum. It has steel inserts. Very reasonably priced and cut out for valves so I can also use to pressure test. The guy will make any changes at no cost other than shipping. Dale I will send you his info. Very nice piece.

Re: Thoughts/Opinions on Piston Rings
 

Hey Thanks Tony! Can you drop me a picture of the one you have? Might be easier to just buy one from somebody who already has them designed, versus making them myself (even though I have a 3D CAD Model for heads).

Appreciate the help!
B&S

Re: Thoughts/Opinions on Piston Rings
 

As always, big Thank You to all who shared thoughts/opinions on this subject. As I mentioned in my OP, the use of Ross pistons in this engine is an overkill, but going a bit further, their price is not THAT much more than a set of say, Egge. The clearance, isn't that much more, particularly is a torque plate is used for honing, and well, they are such a wonderfully machined piece. But, the Rings, I just want to use something more modern, less friction, better seal, ect. I will call Egge and try to find out what combinations might be available.

Re: Thoughts/Opinions on Piston Rings
 

Shoebox,

I could be wrong, but I do believe all Ross pistons can be ordered with metric ring packs. There may be an uncharge, but I believe they do offer it.

I also wouldn't rule out Arias pistons as well.

Tim

Re: Thoughts/Opinions on Piston Rings
 

Tim,
Yes, from an exchange I had with one of their guys a few months back, I got the impression they could do most anything you want.