Piston Rings.

Post by **wanderinstar** » Fri Jul 18, 2008 9:40 pm

Can anyone tell me what the ring gaps should be for a standard bore, also is there a knack to fitting them. Thumbs or special pliers?

Post by **bmcecosse** » Fri Jul 18, 2008 9:42 pm

Thumbs - and never had to 'gap' one yet Ian ! As long as there IS a gap ie they are not solid closed they will be fine.

Post by **Alec** » Sat Jul 19, 2008 7:12 am

Hello Ian,

I concur with BMCE on the gap, that is my experience also. However, I prefer to use ring pliers. If you do use your thumb be careful as they are quite sharp?

Alec

Post by **wanderinstar** » Sat Jul 19, 2008 10:14 am

OK then. Thank you both very much. Finally getting round to building up spare engine Roy. Have had block pocketted, ported head a fair bit and just had it all painted. What is anyones thoughts on triple angle valve seats and 30deg cutback on valves. Will it be benificial on a 1098 with a 1275 head? I tend to think not, but am willing to stand corrected.

Post by **Alec** » Sat Jul 19, 2008 5:42 pm

Hello Ian,

I do a triple cut when I do a head but I can't say how much benefit it is. Certainly a narrow seat is supposedly a good thing and as I have a lathe making up the pilot and stones is quite easy.

Alec

Post by **bmcecosse** » Sat Jul 19, 2008 5:53 pm

Narrow seat on the inlets is good - in fact so narrow there is just a line ! This is achieved by cutting the valve throat out - you can take away quite a lot! Exhaust - just leave the seats as standard for best heat transfer. Well worth going down the exhaust throats - the corner at the guide is VERY tight and it can easily be opened up to allow the gasses an easy run round the bend!