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Forum namePerformance/Engine
Topic subjectPistons and engine bore
Topic URLhttps://forums.2gnt.com/dcboard.php?az=show_topic&forum=i5&topic_id=121790
121790, Pistons and engine bore
Posted by Max-Eclipse, Jul-13-06 07:51 AM
I had my block bored for +.04 JE pistons, and when I picked it up, they said the pistons I gave them aren't the right pistons... and that they don't think they are even for an eclipse engine of any bore... so, my question is, what size should the bore be for .04 over pistons, and what should the diameter of the pistons be?

I would search for this but I've been trying to find time for the past week to just ask this on here... I've got to get back on the road, so I'll check back later.

Thanks.
121791, RE: Pistons and engine bore
Posted by DR1665, Jul-13-06 08:12 AM
http://www.allpar.com/model/sebringcc.html

Bore x Stroke
3.44 x 3.27 (87.5 x 83.0 mm)

What do they mean "wrong pistons?" Where did you buy them? Are they saying they're too large? Too small? How did they bore the block if they didn't have the pistons? (Having the "wrong" pistons is the same as not having any at all, imo.)

Sounds sketchy.
121792, RE: Pistons and engine bore
Posted by cougar694u, Jul-13-06 08:22 AM
Stock bore is 3.445", so a 0.040" oversized piston should be 3.484" minus the piston to cylinder wall clearence, which isn't much.

It'd be safe to say the piston should be a hair under 3.484", but not less than 3.445".

**EDIT**
Stock bore in mm is 87.5 as brian pointed out, but 0.040" oversized is 1mm, so you're now near 88.5mm.
121793, RE: Pistons and engine bore
Posted by Max-Eclipse, Jul-13-06 11:34 AM
I bought the pistons from Nine5eclipse03. I took the block and stuff to the shop first, and told them I would bring the pistons and rods to them the next day or day after. I took the block up there first cause that's the day i was in the area with our truck so it was easier, but I didn't have the pistons with me. When I took the pistons and rods to them, they had already bored it .04 over cause i told them that's what the pistons were that i had. I'll go measure the bore and the pistons in a bit and report back.

Thanks for the replies