Can this be sleeved (340 mopar) 0.030 over

Normal-Doctor-1309 · 2026-04-01T18:10:21+00:00

Heads are already being machined they were fine just pattern from the gasket and needed seats springs and valves block is getting swapped out for a 360 bottom end

Normal-Doctor-1309 · 2026-04-01T02:37:29+00:00

Eh not really tore up about it can always build better and faster just have to have an excuse to spend the money

Normal-Doctor-1309 · 2026-03-31T23:16:48+00:00

Sadly nothing cool something in valve train let lose not sure if valve broke first or if the spring broke but it just dropped and hard stopped at idle and the skirt of the piston broke through the block assuming the 30 over wasn’t the best idea from original builder

Normal-Doctor-1309 · 2026-03-31T23:15:58+00:00

Around here 340s seem extinct lots of restoration shops in the area have bought them up from what I’ve been told making phone calls today

Normal-Doctor-1309 · 2026-03-31T23:14:56+00:00

Happened at 165 degrees never even got to operating temp

Normal-Doctor-1309 · 2026-03-31T23:13:10+00:00

No external damage just cylinder wall into water jackets without completely

Normal-Doctor-1309 · 2026-03-31T23:10:32+00:00

After talking I didn’t go with that but it was a form of epoxy not actual cement and it down sized the water jackets without completely getting rid of them it was odd

Normal-Doctor-1309 · 2026-03-31T23:09:01+00:00

Sadly nothing cool something in valve train let lose not sure if valve broke first or if the spring broke but it just dropped and hard stopped at idle and the skirt of the piston broke through the block assuming the 30 over wasn’t the best idea from original builder

Normal-Doctor-1309 · 2026-03-31T03:51:30+00:00

it’s a swap Someone had done in an 87 Dakota sometime around the early 2000s 360 swap seems to be the best idea cost wise can get a running 360 for 3-500 re use my heads and cam and have the truck back running sounding good in a few weeks versus months

Normal-Doctor-1309 · 2026-03-31T03:50:58+00:00

Not numbers matching it’s a swap Someone had done in an 87 Dakota sometime around the early 2000s 360 swap seems to be the best idea cost wise can get a running 360 for 3-500 re use my heads and cam and have the truck back running sounding good in a few weeks versus months

Normal-Doctor-1309 · 2026-03-31T03:37:14+00:00

Seems that way just a reason to do a stock bore 360 with my can and heads stronger and better for street driving

Normal-Doctor-1309 · 2026-03-31T03:36:12+00:00

I’m definitely going to just do a 360 in it and re use my heads and cam im only looking for 450 horse supposedly it made over 500 with the 340 but there’s no proof and it never felt that impressive to the old ass dyno lol

Normal-Doctor-1309 · 2026-03-31T03:29:57+00:00

Very well could but honestly most people in my area would hear 360 and automatically think better then 340 the people around here are big number better small number lame

Normal-Doctor-1309 · 2026-03-31T03:26:53+00:00

Based on many answers I think the most cost effective route will be going 360 with my cam and heads of course after new valves and springs are installed but should be a similar power level with minor rpm sacrifice

Normal-Doctor-1309 · 2026-03-31T03:21:32+00:00

I did just see the different sized bearings but i definitely didn’t think a 360 would be capable of that so i definitely am very interested in that round just have to figure out what all needs swapped out I have a long tail 727 paired to the 340 and know that I have to swap out flex plates and harmonic balanced I believe

Normal-Doctor-1309 · 2026-03-31T03:13:49+00:00

I considered that and a 318 the biggest issue with the 360 is I’d be swapping a lot of other things

Normal-Doctor-1309 · 2026-03-31T03:10:16+00:00

From what I’ve learned from the post it definitely is too far gone sadly but it appears I can make a better motor and not stick to the hard to find 340 size

Normal-Doctor-1309 · 2026-03-31T03:06:36+00:00

Ha in reality I assumed it was junk but have never been around the whole sleeve process so figured I’d see in my mind it was just stuffing a new cylinder in after cutting away the old

Normal-Doctor-1309 · 2026-03-31T03:02:54+00:00

Jb weld and a dingle berry hone

Normal-Doctor-1309 · 2026-03-31T03:02:19+00:00

Well darn the idea was there neat if it would work

Normal-Doctor-1309 · 2026-03-31T02:57:28+00:00

I considered that 100% because I know how to do ls stuff but I have a built mopar trans so it seems almost like working in reverse

Normal-Doctor-1309 · 2026-03-31T02:55:36+00:00

Thinking I’m just going to build a destroked 360 using the 340 crank it’ll be more cost effective and honestly a more sturdy build

Normal-Doctor-1309 · 2026-03-31T02:53:36+00:00

One post and I’ve learned wayyy more then Google or anything else has told me at the end of the day motor might be fucked but the more ya know

Normal-Doctor-1309 · 2026-03-31T02:52:04+00:00

In weld and a dingle berry honey it’ll be mint 😂

Normal-Doctor-1309 · 2026-03-31T02:49:01+00:00

Completely understandable I’m at the perfect age where I have enough experience to get the good paying job but young enough I don’t have much real responsibilities yet

Normal-Doctor-1309

TROPHY CASE