Finally got around to pulling the motor. Removed the intake and valve covers and looks much better than I expected. The car had 94,000 miles when I bought it 3 years ago... no history on the motor was provided. Only think I did was swap the 2 barrel for a Holley 650 and TA Stage 1 intake. I have put 1,500 miles on it since. My plans were to do the below and there is a link to the previous thread around the mods. Now that I see how clean the motor is I am thinking some I can do myself. a) I think I can replace the cam, lifters, rods, myself but I should probably have a shop install the cam bearing? How can I tell what cam is in there? b) can I replace the rear main seal myself, (Do you have to remove the crank?) Any suggestions on what to look for? Or do you suggest I just take it to the shop and have them do it all? Thanks for any input. PLANS 1) mill the heads down .060 2) shorter push rods by .050 3) replace Cam with maybe TA 212 or crower and replace cam bearings. (think I am going with Crower Level 3) 4) headers with 2.5 dual exhaust 5) new lifters 6) new timing set 7) replace main seals 8) look into distributor upgrades/power timing 9) take to shop to dyno tune and set carb. http://www.v8buick.com/index.php?th...need-a-little-more.320198/page-2#post-2684458
replace with a 455..instant 100 plus HP... It's good you have a plan. Don't rush it and make sure the machine shop doesn't have the sbc attitude doing the machine work..What year is your motor??
Thanks Pat, thought about the 455... but I'll keep the 350 as its just a driver...Further tear down. Still amazed at how nice it looks (except for the crap in the oil pickup). Makes me think of having the heads done and putting in pistons besides the other mods such as cam. Can I put better pistons in and shave the heads .060? I took some measurements: (with my digital Harbor Freight Micrometer so not sure how accurate) Cylinder diameters average 3.825 inches (is this standard bore, .10 over, .20 over?) At TDC pistons are about .100 from being flush from the top of the block Small valves measure about 1.54 Large Valves measure 1.875...... these stock valve sizes? Why are some of the valves white? (burning too hot?) Do the heads look like there is enough meat to shave .060 and do they look ported? Take a look at the pics, still see cross hairs from previous hohn. Although a few have some lines.
The white-ish look on the exhaust valves is normal, the wet black (oil and soot) isn't. When you have the heads done, have them cut the exhaust guides so you can run seals on them, Buick didn't use seals on the exhaust guides.
Cylinders, bowls, and valves pretty much looked identicle to mine. The white is normal and from what I've been told the black gooped up ones aren't unusual either for a 40+ year old engine especially if its been a long time or never that the heads where pulled. years of oil, leaded gas etc. will do that. Check it out here. Lots of good info attached to this thread. http://www.v8buick.com/index.php?threads/heavy-build-up-on-valves-what-does-it-mean.320385/
Lay off the silicone when you do the intake next time, it only goes around the water ports, and very thin at that, use copper gasgacinch around the intake runners. Clogging up the pickup with debris isn't good. Going crazy milling the heads is going to require milling the intake to match and narrow your can selection greatly
Looks like engine has been rebuilt before. Aftermarket Pistons. Factory ones have a raised dimple in center. With the right tuning you might see 100 hp increase and good increase in torque. Yes you can get better Pistons. You won't have to shave heads as much or at all . Seen some forged Pistons nos on eBay but I don't think they where .020 over. Buick v6 Pistons will work and they have skirt coatings on some, can get forged. Try to measure piston depth at top dead center.
Great, thanks all. (Andy) I put the heads back on to transport it to the shop.....If my cylinder bore is about 3.825 is that .030 over? Could I hohn the cylinders and find .030 pistons? Would these pistons be good for a driver to get the 10:1 and some added HP? (Still have the heads done (maybe .010 shaved rather than .060, valves done, crower cam, lifters, push rods etc.), then power timing, bigger oil intake etc. http://www.ebay.com/itm/171054543208?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT Thanks, I have received some good feedback from all!
You will get about 9.3 with those. Still a good bump . Would work fine. They will have to bore to meet the .030 and get ring clearance. Valve job may be recent with rebuild . You may not need that but get springs replaced for cam you use. Crank should be fine. I would take .020 off block bring piston closer to deck. That would increase effectiveness in cylinder. And the 70 engine had a .020 thinner head gasket so why not match it. You will be 9.6 ish. Would be fine for pump gas.
I would start by having every aspect of the engine measured by the machine shop before buying anything.
Chances are that you are measuring the bore at the top with your "mics" that I suspect they are digital calipers. The top of the bore with all that oil it looks like you were burning in the heads is probably built up at the top of the cylinder so your measure is .005" small and your actual over bore is .030" over. Only time you'll see a .025" over bore is with custom pistons. Have your machine shop measure the bores like Sean said before you buy those pistons, to make sure the bores won't be to big after they're honed, you may need to go to .040" over or get a custom or customizable piston. It is always better to have the block's deck milled rather than have the heads excessively milled to raise compression. Milling heads excessively is for when people don't plan on disassembling the rotating assembly or removing engine from car to up compression. 10:1 is to much compression with a Crower L3 cam, your dynamic compression would be to high for pump gas. Try to stay around 9.5:1 or slightly lower with that cam. There are better cams if you want to run 10:1 static compression, like the TA 413 is a good one but you may need roller rockers for that one? The TA_290-94H would be a good 10:1 cam if you have access to 93 octane. GL Derek
if your pistons are .100 in the hole thats no good. you need to get that below .050 at a minimum. a piston swap with a better pin height would be the least intrusive way to do that. your compression must be in the tank.
