I know some who really despise total seal rings...more than like it. I vote you talk to the machinist and find out.

Total Seal never went anywhere. But you'll see lots of opinions for and against them everywhere.

I know at least one person who despises the rings that came with the wiseco's--me. I have more blowby than I really should have. In reality, it's probably less the fault of the rings and more the fault of the machinist. Northwest Connecting Rod in Seattle FTL. :cry:

I wouldn't use the top rings. Just use the seconds, and find a machinist who's worked with them before. Cylinder wall finish is important with any rings, but some say it is particularly important with the TS rings.

You are going to have more blowby with aftermarket pistons. You run bigger gaps. Who cares....just run more boost.

Just compare the thermal expansion coefficients (CTE) of the two alloys.

OK, I'm bored, fuck it I'll check it out...
According to Belfab they use 4032. According to Wiseco they use 2618.
Looking up the CTEs for both materials, using the T6 condition:
Aluminum 4032-T6 has a CTE of 10.8 µin/in-°F
Aluminum 2618-T6 has a CTE of 12.4 µin/in-°F
(properties taken from Matweb)

Therefore, the Wiseco piston will expand about 23% more than the Belfab piston for a given temperature rise. CTE is a function of temperature, so I used the same temp range for both alloys.

The less expansion, the longer the motor is going to last.

You need to get laid. My shit is tuned off boost. Doesn't change the fact that you came from a tired-ass 1.6, and I came from a strong 9.5:1 compression 99 motor.

Yeah but if I can spend $80 and get rings that will net a couple of hp while keeping my oil cleaner and my crankcase pressure lower, I'd do it in a heartbeat. Too much trouble to tear my shit apart now. If ever I have a reason to tear apart the motor, I'm getting TS rings.

I've heard many suggest that after a few hundred heat cycles, they expand at the same rate. I went with a "loose" bore and I have no problems or excessive noise.

I don't have much of any...but my oil turns black fast. I need to do an UOA to see if its fuel contamination.

You are now on to what I am refering to here. My point is that the additional blowby is not a big issue. The motor is going to be more loose than a stock motor. This is not a bad thing. Plus more frequent oil changes are to expected with a built motor.

my cylinder walls arnt foil thin......

Attachment 204924

Your cylinder walls are not what you need to be concerned with. The thickness of the remaining sleeves is. At the bore they are getting radically thin for boost.

Never heard that one. Let me know if you run across any hard evidence of that. I am not sure that is possible since CTE has to to with molecular interaction (chemistry) so the core chemistry of the material would have to change somehow.

I think its more of an issue with load. I expect a motor that run 15psi for 30-minute sessions, 2-hours per track day to warrant our conditions.

Sorry to butt into the piston thread, but I also just bought MTuned rods and am looking at pistons. My machinist said he could get me JE Pistons 9.0:1 83.5mm for $510 including the pistons,wrist pins,and rings. This sounded like a pretty good price to me, but wondering what the consensus is on the JE vs. others being discussed in this thread? Thanks

I'm in the market for pistons as well. I vote we all decide on one brand of piston and try to get a group buy going from one of the sponsoring vendors or whoever can get a good deal.

You also need to look at fatigue life of 4032 vs 2618 at elevated temperatures...

2 reasons I didn't do that

1. I worry about thin cylinder walls at 400whp+
2. The only HG available that will do a 2.5mm overbore is the Maruha copper gasket, at $160. Seeing as how I went through two OEMs before one sealed up, that would have cost me a fortune.

Decisions, decisions...

One would expect either piston to massively out-perform a stock unit under extreme abnormal aspiration. I tend to gravitate in the direction of the Supertechs on the basis of their lower thermal expansion and consequently tighter bore tolerance.

With a loose bore, you can rub it hot for a while before the piston scrapes the wall (loose bore, not loose tolerance). My builder suggested going a little-loose if it sees the track.

I had the benefit of using a builder who's done so many FI miatas that tolerance and bore decisions, which varied by piston material, were chosen from experience and not some general text-book rule.