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[Jorsher]

Here's what I found with a Google search:

For a nitrous or blown racing engine, the top ring end gap sould be opened up to as much as .006 or .007 inches times the bore diameter. Now we're looking at a 2nd ring end gap of .024 to .028 inches in an engine with 4 inch bores.

For the 2nd ring on a nitrous or blown motor, the recommended ring end gap is even wider: .0063 to .0073 inchestimes the bore ( or 0.025 to 0.029 inches with a 4 inch bore).

The recommended ring end gap for oil rings regardless of the engine application is typically .015 inches.

Some racers believe that opening up the 2nd end gap even more (say an additional 10%) can improve overall ring sealing by allowing trapped gases to escape before they blow past the top ring and cause ring flutter at high rpm (say above 5000 to 6000 rpm).

From Wiseco:

                                                   Top              2nd              Oil
High-Perf. Street/Strip .................. .0040” ........ .0050” . ... ... .015”
Street-Moderate Turbo/Nitrous ..... .0050” ........ .0055” . ... ... .015”
Late Model Stock .......................... .0050” ........ .0053” . ... ... .015”
Circle Track/Drag Race ................ .0055” ........ .0057” . ... ... .015”
Nitrous Race Only ........................ .0070” ........ .0073” . ... ... .015”
Blown Race Only .......................... .0060” ........ .0063” . ... ... .015”

The pistons I have are the K542M815 pistons on page 8 (6 of 27). 
http://www.cylmo.no/arch/_img/9072658.pdf

Ultimate goals for this is 450-500whp.  It's a B18B block, B18C5 head, GSR cams, TT B18C forged rods, Wiseco B18C forged pistons, and a B18C crank resulting in 9.62:1 compression with OEM headgasket.

I'm assuming I'd use their specs for "Street-Moderate Turbo/Nitrous."

Thus:

Bore:  81.5mm bore / 25.4 = 3.2087" bore

Top ring:  3.2087" * 0.005" = 0.016"

2nd ring:  3.2087" * 0.0053" = 0.017"

Oil ring: 3.2087" * 0.015" = 0.048"

Sound good?

Also on the page with the Wiseco ring gap information it has a suggested placement of the gaps in relation to the piston... Should I bring this to the machine shop and risk offending their intelligence, or is it basic knowledge that they should already know?

Any suggestions on what rings I should use?

Grassyass.

[BoostedSchemes]

tell the machine shop the specs you want for every fucking bolt they turn, i guarantee you they are full blown retards regardless of what you heard

also make them right down the spec for everything they do, and yell at them if everything matches your requests. also if it doesnt.

[Jorsher]

The yelling occurs the first time I talk to them.  I know the importance of making a good first impression.

[HiProfile]

I think the Laskey Racing website has some of Earl's formulas on it still, but last time it took a while to find. It will be quoted on hater-tech somewhere. I followed it exactly for each ringpack and get very little blowby but obviously no bind yet.

[d112crzy]

http://laskeyracing.com/shop/ringgap.htm

I like to go on the loose end. Even more so if its for a big power setup. Also, 99% of the time you don't need to do anything to the oil control rings. But I measure them every time just to be sure the ends don't touch.

Your pistons should have come with a page that talks all about ring gaps as well. I know some do.

[sikefcrx]

Go ENDYN or go home!!

http://www.theoldone.com/articles/engine_tips/piston_facts/pistonfacts.htm

Built my LS/V to there specs and know tons of guys that build to there end gap specs.

[ryan89crx]

http://laskeyracing.com/shop/ringgap.htm

That's the write-up I follow on all my builds/rebuilds

[Jorsher]

Cool, well buying the piston rings tomorrow.  I may have the shop gap them if they charge the right price.

Is a torque plate really necessary on a Honda block?  I see them suggested but judging by my ring compressor thread, I doubt you all have bothered with them.

Just making sure I do this shit right...

[widebody93]

My shop didnt use a plate on my H22"both builds", but its closed deck, but also when D-Rail was building his D I know that my machinist didnt use one on it either. I see the importance of them, but have yet seen one used.

[Jorsher]

Sounds like one of those suggested things that nobody follows.

[Minor Threat]

Sounds like one of those suggested things that nobody follows.

No, it's one of those things that you do on oldschool V8s because there's not much material on the mains, so the bolt actually moves things around. Honda blocks tend not to have that problem.

[patsmx5]

Sounds like one of those suggested things that nobody follows.

some miata guy had his machinist measure a bunch of shit on the motor with and without the torque plate attached, and it made no meaninful difference either way. Granted, this is an iron block, closed deck I4. Just for reference.

[speedjunky01]

so this look right?

d16 75.00 bore

1st ring:
.006 x 3.00 = .018

2nd Ring:
.0065 x 3.00 = .0195

same for 75.5mm bore

[d112crzy]

what rings

[bigdaddyvtec]

http://www.cp-carrillo.com/LinkClick.aspx?fileticket=p7ROWY4k9zk%3d&tabid=74

APPLICATION TOP RING SECOND RING OIL RING
Street / Hi Bore x .0045” .004” - .008” Min..015”
Performance
Drag Racing Bore x .005” .004” - .008” Min..015”
Road Racing
Nitrous/Turbo Bore x .0055” .004” - .008” Min..015”


Important: Ring sets are manufactured to fit specific bores. For
every .001” over the intended bore size, ring gap will increase
by .00314”