Hey guys. Well I am putting in new pistons on a 350 that I am building. I dont know if this is the right place for this but has anyone put piston rings before I just need help on the oil ring where u put the the expander ring and the two other rings. In the instructions it says that the top ring suppose to be 45 degrees left of the expander ring and the bottom oil ring suppose to be to the right 45 degrees from the expander ring. I need help on making them 45 degrees away from the expander ring any tips. Do they have to be exactly 45 degrees? And after the 3 rings are on is there a direction they have to face when the piston is put inside or it does not matter. Well guys hope anyone can help me out here. thanx in advance.

 

Can't say for certain for cars, but in aircraft engines we set 'em approx 120° apart so the gaps were basically as far from each other as possible without overlap. I'm guessing the 45° specified is a minimum, the concern with aligning the rings is to prevent blow-by.

 

Oh ok i see. well i re read the instructions and they do mention 120 degrees. it says the gap between the expander ring and the oil rings should be from 45 degrees to 120 degrees i guess i was reading through it to fast. so that would mean they dont have to be 45 or 120 degrees right it can be in between right.

 

Yes anywhere between would be fine. The biggest thing is that the gaps don't overlap anywhere. I usually put my top ring at 2 o'clock, the 2nd at 5 o'clock, expander ring at 9 o'clock and the rails at 90* from the gap in the expander ring.

 

Oh ok ill look into that before i stick them in. Thanx for the input guys. Wish me luck this is my first build hope it goes well.

 

good luck, let us know how it turns out!

 

They don't have to be installed with the gaps facing in any particular direction when you drop in the slugs.

 

well i hope i did it right all the pistons are in. I made sure the gaps were not overlapping and made the 2 oil rings 45 to 120 degrees apart from the expander ring. i just need to buy some gaskets and put it back together and then start it up and see what happens. . THANX el_muerte, toomany and Viprklr for your help.

 

Now just make sure you don't treat it too nice when you break it in... After you know it isn't going to leak everywhere and you get that first oil change done after about 30 minutes of break-in in the garage, you need to POUND on the thing!

Rings break in by creating cylinder pressure with high load, WOT operation. The cylinder pressure builds and pushes on the back sides of the rings and forces them to wear into the cylinder wall and create a good seal. WOT under a load on a dyno or in the car going down the road is the only way to get this done. Don't be surprised if you leave a smoke screen the first few times you make WOT runs depending on the ring material and cylinder surface after machining...

Don't be afraid, get on it right away!

 

Oh ok. Sounds like fun hehehe. so after i get it running for like 30 min. and do a oil change i will have to go out and drive it around in WOT correct. is this WOT break in good for a new cam as well i would guess it is right. around how many runs you think is best. Thanx again.

 

you want to avoid idling at all costs... you'll glaze the cylinder walls and the thing will burn oil. fire it up long enough to make sure it will idle, then you should be on the throttle. whether you do it in your garage or on the road i don't think will make a difference but you don't want to idle, and avoid maintaining the engine at any rpm for any length of time... you'll want to vary the speed, especially during the first part, to properly seat the rings. if you go driving, put it in neutral at stoplights and give it a bit of throttle just so it doesn't idle.

 

ok got it. and how long would i have to do this break in process just for the first day i start it up or a couple more days like a week or so, when will i know i can drive it regularly. thanx guys for the input. you guys helped a lot.