My repair manual shows that oversize pistons were avaliable up to .035 so I would assume that you could go at least that with out problems. Do you know of a source for pistons?
In the past, I used standard 3 7/16" Chrysler pistons. These pistons will give the W5 a .060 overbore.
They are a lot more affordable than buying from Egge.
Do You own a car built by Durant? 1923 Star touring, 1927 Star Coupe
Hi guys
I believe my car was originally a 3 1/4 bore. I put international pistons in it and they were 3 5/16. The cylinders were so badky worn that they are now bored to 3 5/16 and .030 size at that . these are very heavy wall blocks so they will take a lot of boring.
I think the only thing we have to watch for is heat
Hope this helps
Ken
Do You own a car built by Durant? 1930 Durant Deluxe Rumble Seat Coupe
Hi guys.
As a lot of you know I have restored a lot of our cars and helped a lot of our members and with the engines. All the continental engines from W4 & on can be bored to at least 100 thousands with no problem. We (Kenyon machine Shop San Diego) have bored them that far before and no problems, very thick blocks. A couple tricks is get a modern light weight egg shaped three ring new piston. Rick Botti our club president got these kind of pistons from Australia for us to use in his engine. The advantages are substantial to less heat and less drag and HP loss with 3 rings instead of the original 4 rings. No one has used a 4 ring piston for a long long time. Also x-ray the rods and balance all to equal weight and have then peened. That is important as these rods are small & fragile. Also have the cam reground to lift the valves at least 75 thousands more ( there is plenty of room in the head and plenty of adjustability in the tappets) and have at least a 10% duration added to the intake and exhaust lobes and mill the head at least 100 thousands and ream and polish both intake and exhaust ports in the block and the manifold. Now you can run the next bigger carb. This will give your car enough horse power to get out of it's own way. Ask Rick about the improvement.
Have fun. Later Lance Haynes
Where Are You From? www.lancedurant.com
Do You own a car built by Durant? a whole bunch of them.