Piston rings recommendation

gslender · Postby **gslender** » Sun Feb 10, 2013 9:17 pm

Got std pistons, but wondering what folks use for piston rings? Anything strongly recommended, or just use whatever Repco flog you?

G

toppertee · Postby **toppertee** » Sun Feb 10, 2013 9:28 pm

Does this mean we can buy a ring grinder?

gslender · Postby **gslender** » Sun Feb 10, 2013 9:30 pm

toppertee wrote:Does this mean we can buy a ring grinder?

What for?

toppertee · Postby **toppertee** » Sun Feb 10, 2013 9:34 pm

gslender wrote:
toppertee wrote:Does this mean we can buy a ring grinder?

What for?

You have to grind the rings to fit. Plus I'm no good with a ring file.

gslender · Postby **gslender** » Sun Feb 10, 2013 9:55 pm

Dremel baby.... It does everything!

G

tbro · Postby **tbro** » Sun Feb 10, 2013 9:58 pm

Just get a set of ACL rings, BUT you will need to measure what thickness the oil control ring is 3mm or 4 mm, and order as required.

You will need to measure ring gap in the bore but I doubt that they will need filing as the std bore used with a hone will probably be at max diameter.

If you don't know how to do this I'll try and find some training info and post.

Terry

toppertee · Postby **toppertee** » Sun Feb 10, 2013 10:09 pm

gslender wrote:Dremel baby.... It does everything!

G

Got one of those already!
I need some more tools....

Zcootz · Postby **Zcootz** » Sun Feb 10, 2013 10:25 pm

I went with gapless rings on my last build and never looked back. They only cost a fraction more than the cast iron.

Out of interest I wonder who makes ACL rings these days, I used to do some engineering work for them when the rings were still being machined in Melbourne?

Matt · Postby **Matt** » Sun Feb 10, 2013 11:18 pm

Hastings made the gun rings back when I was in the trade. Not sure if they're still available, but I used them a lot and found them excellent.

wozzah1975 · Postby **wozzah1975** » Mon Feb 11, 2013 1:32 pm

+1 for Hastings. If you are using the OE pistons and just honing the bores make a point of just using a cast type ring in it, not a moly or anything fancy.

Cheers
Woz

booki89 · Postby **booki89** » Sat Mar 05, 2016 12:22 pm

Bit of a bump from the past, but its relevant to my situation today.

I am reconditoning my MX5 motor, and the gaps from the old rings were within spec from new - 0.25mm off the top of my head.

The new piston rings I got from hastings are at 0.50mm !

Would you use these new rings?
Where can i buy some rings that will fit my car, I have already exchanged these rings once due to poor ring gap.

manga_blue · Postby **manga_blue** » Sat Mar 05, 2016 5:45 pm

I've got NPRs off eBay for std pistons and lightly honed bores. 40,000kms on those now, including 5,000 track - still have 210ish compression, no smoke.

booki89 · Postby **booki89** » Sun Mar 06, 2016 10:59 am

What type of ring end gap did you run magna?

manga_blue · Postby **manga_blue** » Sun Mar 06, 2016 2:11 pm

booki89 wrote:What type of ring end gap did you run magna?

It's manga, not magna. :twisted:

I just ran with Mazda factory specs.

Source: Mazda NA8 Technical Data at http://mx5cartalk.com/forum/viewtopic.php?f=76&t=46376

The NPRs were SWT20066. Google that for dimension data. They were easily in spec straight out of the box. No grinding or filing needed.

Engine had 170,000 kms on it then with little or no visible bore/piston wear. It was overhauled because of a crank nose failure.

booki89 · Postby **booki89** » Mon Mar 07, 2016 9:54 am

Thanks manga, these are the same specs I am shooting for.

My Hastings rings are getting me 0.5mm gap on my top rings and even larger on my oil rings, so I am hesitant to run them.

Will be looking for another brand....as the rings that came out of the engine were within that factory spec!