line boring/horizontal boring

[sw1]

i have a motor out of a boat which im going to rebuild at one stage or-a-rather. its a v8 cleveland 302.

was talking to a bloke at work & he mentioned horizontal boring. i have never even heard about this before. he stated with the crank prefectly straight it will just be a lot free'r. rang an engine place and they stated that there are no performance gains to be had by performing this process. & also at around $300 odd, i would like to know if this is actually worthwhile or not

anyone out there know what the deal is, that being - a worth while mod on an engine thats getting a full rebuild.

[Struth]

Sounds part of the blueprinting and balancing process

[PJ.zook]

Basically they torque your main caps on without the crank, then run a perfectly straight reaming device down teh middle. Im no expert, but i dont see any peformance gains in doing it, as if your crank is the slightest bit off then its going to be out anyway.
If you are planning on revving it way above standard redline i suppose it might help removing another possible point of weakness and/or vibration.

[Eddy]

I have had this done on a few blocks, and it's my belief that there are only very small performance gains to be had, however, engine life is increased because of the reduction in stresses on both the block and crank, and the engine will also vibrate less.
Align boring is also a very worthwhile mod, as it puts the cylinder bores in perfect alignment with the crank.

Best done together, as the clevo is very responsive to these mods.

hmm ... while you're at it, why not turn it into a 351

[sw1]

hmm ... while you're at it, why not turn it into a 351

already thought of that.......

bought a 351 crank off of ebay.......

got ripped of by a dodgy seller - one of the journals is below 40......

stupid a$$ wasted my money....

just gonna go the 302 as i dont wanna buy another crank

[-Scott-]

The process described is how the crank journals were produced in the first place. Re-boring/drilling will only be required if something has moved. If something has moved in a cast iron block I'd be wondering why you'd want to keep it?

[Eddy]

When these blocks were bored originally, the equipment used was a little on the flexible side, and also being mass produced, the alignment was "about there is near enough"

[Rem 22250]

Boring of the crank & cam tunnel is worth while for the life of the new bearings, also having the crank machined for the new bearings. Over the years of the engine heating and cooling will slightly alter spec's so machining brings these back within manufactor spec's.

Blueprinting a engine is machining and balancing to actual manufactors drawing spec's.