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Maximum over-bore for a 218?


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Really depends on the wall thickness, although pistons could be an issue. I've seen .080" over pistons for the 218's, but I don't think they're stocked anymore. Still, I think Egge will make them for a little more. You'd probably want to have the walls sonic checked before putting out money for pistons though.

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IF your engine was just rebuilt and only the crank broke and that there was no damage to the block when the crank broke, you should not have any appreciable wear in the cylinder..however to answer that question one would have to mic the bore to measure any taper...if the taper is well below the allowed limit..just go back with what you have..

stock pistons for oversize as offered from the factory...

.005 .020 .030 .040 and .060

tear it down..mic everything to be within tolerance..(the actual act of the blueprinting) and get you a replacement crank..

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I tore it down years ago and it's got some very minor pitting from rust. I can just barely catch my finger nail on the pitting.

I think I'm going to hone out the cylinders as best I can and put it back together.

I'll just keep my fingers crossed for this motor until I can find a T-142 stamped block and rebuild it properly.

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I remember worrying about having my engine bored 0.060 for the rebuild but the mechanic informed me there was nothing to worry about. He said that the 218's used much the same block as the 250's, so the walls were thick. I recall reading a previous thread that spoke of the motor heating up from the thinner walls. I'm hoping to get many years out of my motor before having to go down that track again. I hope it all works out well for you Kevin. I'd be interested to know if you can go to 0.080.

Desotodav

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I think there comes a point where it's just not worth it for that engine anymore, it's not like a 218 is an impossible engine to find....it might even be time to slip into a 230 and gain yourself 2"'s in the front and a few hp to the rear ;),,,or look for a 251 and have a nightmare like me :P

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I probably have. It's a shame though. The motor had just been rebuilt. The guy I bought it from tried to pull a stump out and broke the crank. :D

Rings, bearings, valves and pistons are all in great shape.

Kevin

If the crankshaft broke under a severe load, check the line bore of your engine, guaranteed to be out of tolerance. The tremendous stresses that are involved when a crank breaks will shift the block. If your block is already at max manufacturer size (.060 over) the best thing you can do is harvest your block for all useable parts and scrap it. At the point where you are now you're going to be throwing good money after bad, cut your losses and get another block/engine. Sell your harvested parts to help fund the purchase.

Bryan

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I'd rank a broken crank right up there with a thrown rod as a catastrophic engine failure. The bottom end of the motor has tighter tolerances for a reason, and the previous rebuild might not have addressed that. The motor may be salvaged, but it might be cost-prohibitive. VPW sells blocks for rebuilding, it might be worth the peace of mind to start an engine build with something in a li'l better condition than one that has corrosion present.

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Kevin

If the crankshaft broke under a severe load, check the line bore of your engine, guaranteed to be out of tolerance. The tremendous stresses that are involved when a crank breaks will shift the block. If your block is already at max manufacturer size (.060 over) the best thing you can do is harvest your block for all useable parts and scrap it. At the point where you are now you're going to be throwing good money after bad, cut your losses and get another block/engine. Sell your harvested parts to help fund the purchase.

Bryan

I'd rank a broken crank right up there with a thrown rod as a catastrophic engine failure. The bottom end of the motor has tighter tolerances for a reason, and the previous rebuild might not have addressed that. The motor may be salvaged, but it might be cost-prohibitive. VPW sells blocks for rebuilding, it might be worth the peace of mind to start an engine build with something in a li'l better condition than one that has corrosion present.

Good advice from both of you. I never thought about the line bore being bad.

Guess I'll be more serious in my hunt for another block. Time to check out VPW.

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Call the guys at Hagen's in Puyallup. If they don't have a decent block in one of the jillion storage buildings (offsite), they'll probably still be able to get you one.

The 218 in my truck was done by Centerline Machine in Puyallup in the early 60s. Rings broke in 2005 or so...

Someone used to offer .090 pistons for L6 Chryslers. Been awhile since I thought about hotrodding one...

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Call the guys at Hagen's in Puyallup. If they don't have a decent block in one of the jillion storage buildings (offsite), they'll probably still be able to get you one.

The 218 in my truck was done by Centerline Machine in Puyallup in the early 60s. Rings broke in 2005 or so...

Someone used to offer .090 pistons for L6 Chrysler's. Been awhile since I thought about hotrodding one...

Thanks for the 'heads-up' Scruffy! I didn't realize Hagen's sold used parts.

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