What kinda piston end gap should I be looking at with a 3.1 running about 10psi of boost?

I hear around 20 and some say close to 30 thousands inch.

Good question. I can honetly say I never even thought of that. Im in the (slow) proccess of building a 3400 turbo myself...

After reading this article:

http://www.kb-silvolite.com...?F_id=40&action=read

I guess its best to error on going too large, where as if you go too small you risk the rings butting against one another. Too large, from what this article says, there is such a small difference it is insignificant.

Look into what GM ran on the Turbo Grand Prix, there is no sense in going larger than necessary on a street driven motor since the excessive ring gap will hurt efficiency over normal driving by reducing leak down time and increasing combustion gas contaminants in the crank case, at least it seems to reason as such. .030" is a pretty big gap for a piston ring I would think unless you expect to see temps high enough to keep it closed down most of the time.

I run the gaps on my 3800 about .010 larger than recommended. Too many people were breaking the tops of the pistons, and even though they say the tops breaking was from detonation, i think it was from ring butting. I have a little extra blow by, but i would rather have blow by than broken piston.

quote Originally posted by fieroX: I run the gaps on my 3800 about .010 larger than recommended. Too many people were breaking the tops of the pistons, and even though they say the tops breaking was from detonation, i think it was from ring butting. I have a little extra blow by, but i would rather have blow by than broken piston.

The only time I ever had a problem with ring butting is during an episode of extreme lean condition on a freshly built TPI 305 when I failed to connect the wastegates and over boosted on the first run. No pistons were damaged but the rings were fried and you could see a straight line groove running lengthwise in some of the cylinder bores suggesting they were placed there by the ring ends comming together, otherwise I have always run a stock gap having not given it much thought in the past feeling that as long as I don't lean the engine out I should be okay. I've dealt with the blow-by issue before and I don't care for it at all. I'll be using the Snow Performance water/meth kit and doubt I'll run into any trouble. It's something to think about though.

none

http://www.totalseal.com/

quote Originally posted by Pyrthian: none http://www.totalseal.com/

Thought about those but read an article indicating a down side to their use not long ago.