Silvertop and Arias piston ring gap

[ArubaAe86]

Hi, I'm installing Arias pistons in my silvertop, the Arias pistons are 8.9:1 c.r. and 0.5 oversize. The Arias package came with the rings but I don't know if it is allready grinded to the size I need or do I have to grind them for my setup. If so how much should the 1st and 2nd ring gap be for my setup?

Here is what I'm planning to change on the engine:
- Arias pistons and rings 8.9:1 C.R. and 0.5 oversize;
- 4AGZE supercharcher connecting rods;
- ACL Race bearings with thrust washers;
- Cometic head gasket;
- ARP head studs;
- TOGA High Volume Oil Pump;
- 3SGTE 440cc injectors (injector upgrade);

I'm planning of installing a t3/t4 turbo and reaching about 250 Hp.

Thanks in advance for any help.

[SilverRA23]

Might be worth asking Arias themselves... they were very helpful with all the questions I had.

[3jcelica]

Arias piston rings will need to be grinded to suit the application. The small box the the rings came in should have a spec sheet to suit a given application i.e. high compression NA or boosted.

Also the piston box should have ring gap details based on type of ring and applications, if you do not have these details email arias and given them details on application i.e. revs compression etc and type of rings i.e. cast stainless etc.

I have been through this process as my engine runs higher boost than most => larger gap required.

So yes you will need to grind the rings to a mnufactures specified gap

Roger

[ArubaAe86]

Thanks for the quick reply, based on the given setup, does anyone has any other suggestions? A help on gap sizes would be really nice otherwise I'll have to contact Arias.

[allencr]

This is about rings from Federal-Mogul & a search of their site. I don't know where the PDF is or if it is still on their site.

http://www.aa1car.com/library/ring_info_speedpro.pdf


http://www.federalmogul.com/en/SearchResults?q=rings

[dangdang]

I also run Arias pistons (8.0 comp tho) and .50mm/20thou over in my 4agte and I run 15thou end gap.

[jeffro ra28]

If the rings are not file to fit they are ment to fall within SAE standard clearances, Which for a 2.9" - 3.5" bore is .010" -.020".

Generally if the rings are file to fit they will be specified as being .005" over that of the bore size of the engine and usually have less then .005" gap unfiled. e.g. if you have purchased pistons to suit a 3.000" bore and have received file to fit rings, the rings are actually 3.005" bore rings.

As for gaps, there are no specifications available (alteast with the rings i use) for different rings types and materials, they only specify gaps relative for the intended use of the engine and fuel used.

For which the specification for a turbo charged engine on pump fuel is BORE x .0055" for the top ring and BORE x .0035" for the second ring. For a naturally aspirated street/strip engine BORE x .0045" for top ring and BORE x .0035" for second ring.

Alcy, nitro and Nitrous all use different gap formula's.

These gaps are based on normal operating conditions and are a general guide only. However, for a 250hp 4A it does fall in the "general" category so they will be fine to use.

Also note, Every .001" that the bore is larger then specified size ring end gap increases by .0035". Which is alot when considering a blueprint engine build.

[3jcelica]

I run a 25 thou gap with 2mm overbore for 25-30psi boost 8.5:1. Serously talk to Arias

Roger

[BLK_20v]

+1 on talking to aries...

The time you've spent on here, you'd have your answer by now...

[Bazda]

Make sure the 2nd ring end gap is bigger than the top.
I would suggest around 16 thou for the top and 18 thou for the 2nd ring.