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Old 06-12-2023, 07:35 AM
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Cliff R Cliff R is offline
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Join Date: Nov 2000
Location: Mount Vernon, Ohio 43050
Posts: 18,153
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Here's the problem with the hone-ring thing.

Cylinder walls wear tapered, less at the bottom and more up where the heat is. This "works" the rings too much if there is taper in the bores and they loose their tension quickly. Second problem is the top ring land in the pistons. They wear a LOT faster than the lower ring land leaving the ring loose and it flutters all over the place.

So, IF your bores are straight and piston ring lands tight nothing at all wrong with honing the block and installing new rings. Piston skirt to bore should be fine as that's seldom an area of concern but common sense still applies here they have to be tight on the bores over everything rocks around too much and it will wear out quickly.

Basic rule of thumb is to look at the "ridge" at the top of the cylinders. If none present you are tyipically looking at a lower mileage well cared for engine that didn't get a lot of dust/dirt ran thru it. Those make for excellent re-ring jobs in most cases. If you find a lot of ridge at the top of the bores you don't need a qualified machine shop to tell you it needs bored to the next size.

Same with crankshafts. Most to NOT need much more than polished if the engine was running fine when removed from the vehicle. WIth split precision bearings the bearings never touch the crank so most are in really nice shape if the engine was well cared for and didn't grind up a cam lobe and pump millions of metal particles thru it. Once again common sense applies here and if the bearings look good, crank isn't all scratched up and tore to hell you are good to go there as well.

Valve guides are often in perfect shape with Pontiac heads as they use low lift cams and gentle lobes without a buttload of spring pressure. Still need to be checked to make sure they are really tight. If so you can simply "touch" up the seats, surface the valves and back in business. I always replace the valve springs vs shimming old ones, but will re-use Pontiac retainers and keeps every single time, they are very strong parts. So are the rocker arms and pushrods and can go right back in if not heavily worn anyplace.

Cams and lifters are risky to use again, but then we have all this outsourcing with those parts these days so it's a crap shoot to get good USA made parts to replace them. As for oil pumps and timing sets I always put a new Melling pump back in place, but NEVER just drive the pick-up on it and think it's good to go. This new metal doesn't have any "memory" and you've got to take an extra step to retain the pick-up on the pump or it's coming off after you run the engine in.

As for timing sets I use and prefer the stock 3/4" wide Morse chain set-ups. They are at least 5 times stronger than a cheap double roller variety and will last the life of the engine. The high-end billet double roller stuff is OK, but I've seen enough failures with them in high mileage engines that I woln't use them here for that sort of work. They do make the cam easy to degree and fine for most of these engines based on the way the vehicles are typically used. Most are lucky to see 1000 miles in the next 10 years so using a junk bicycle chain set-up to drive your camshaft isn't really much of a concern and we don't hear about how bad many of those parts really are.......FWIW......

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73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile),