okokko... Culprit is....

[poormillionaire2]

I have sleep and drinking mixed up with school and work.

[Earlsfat]

okokok (yes it's back) what is everyone saying? Hot tank it, hone the cylinders, (WTF is plastigage?), replace bearings, re-use pushrods / lifters (practically new) / and rockers (again practically new), and re-ring it?

Cylinders look great except the last 1/8" or 3/16" at the top is sort of rough / carboned up... that's the part that is making it need the honing.

You know what... I'll have to post pictures so you guys can see what I'm talking about.

(Babs, head bolt appear ok... all the rest look just like the used what they had on had and shimmed them up with 2, 3, or 4 washers. The kit I was looking at didn't include the head bolts, but did have everything else.)

[wrightz28]

You need plastigauges as a easy way to determine your journal to bearing clearances, unless you want to learn how to use a micrometer and t-gauge. Which in all reality, you should do anyway, and the use the plastiguage as a means to doulbe check.

[1986Z28]

plastigage is a thin little piece opf plastic that is used to check oil clearances btween the crank journals and the bearings, its placed on the crank journal between the main bearing and the journal you torque the main cap to spec(id torque it 3 steps, and you compare it the the measurements on the plastigages package, usually available in increments of 0.0005" or 0.001", ball hone is super easy to use, but if you knock the glaze off the walls and the carbon spend the money and buy a set of rings(buy the right size depending on if your engine has been bored over 0.010", 0.020", 0.030" etc) also not to sure on BBC's but with aftermarket SBC pistons, there are different top rings thicknesses(top 2 rngs) ive seen them in both 5/64 and 1/116", BUT like i said i dont really know on BBC's also before you buy bearings make sure you know if the crank has been turned and how much(if any), easiest way to tell(if the machine shop that did the crank didnt mark it) look at you old bearings, both main and rod, they may say STD on the which mean, they are for a standard dia. journal. or they may say 0.010" or maybe 0.020" depending on how much the crank has been turned. As far as head bolts, there never a bad thing to replace when you have the heads off, they will actually stretch when you torque them, which can kill the threads in the block if you re-use them and you may not get an accurate torque reading off them. OK THAT WAS LONG WINDED IL SHUTUP NOW

[Earlsfat]

okokOK! New head bolts it is. I have no idea what that other stuff meant. (I'm serious too, I have no idea what you guys are talking about. Crank journal bearing clearances??? )

Took heads to speed shop... Between $350-$500 to have the valves sleeved new valves, and all the bs he said they had to have so that they'd run . He said that they've been ported.. although whoever did it didn't know what they were doing, and took too much out of the exhaust ports and the result is that is kills the exhaust flow and power. Now... if you can feel the exhaust from like 15 feet away from the car when the engine is revved... how much effect does over-porting the exaust ports have?

He also said that the valves are SO bad that they are definitely the source of ALL the issues the engine was having... compression, vacuum, etc.

ALSO... I found out that the previous owner put an oversized pulley on the water pump which made the v-belt wear on the radiator hose WHICH... accounts for the burnt rubber smell I mentioned a while ago.

ALSO I found out the friggin header bolts were too loose, accounting for my exhaust leak.

[wrightz28]

alrightalrightalright.

Bearing clearance: There is a razor thin, thousands of a inch gap, inbetween the main bearing and the crankshaft. The crankshaft journal is the area of the crank that is nestled up inbetween the block bearning and the main cap bearing (hope you didn't mix those boys (mains) up yet You also have the connecting rod journals as well, same concept but apply the connecting rod to it and you get the picture. This allows oil to do it's job.

Here's my problem thus far with what your'e saying. The burnt and hung valves are the cause of your currnet ill running motor, great BUT, what burnt the valves??? Overly bored exhaust ports in my opinion may have let the exahust kind of lumber around and "wait it's turn" sort of like a whole bunch of people trying to exit a sports arena all at the same time, you know how a cluster of people end up sutck to the side waiting their turn to get to the exit? So I think it was causing a poor unorganized lfow and not getting pushed out the way it should and there is your burnt valves.

If the head bolts are not torque to yied you can reuse them. Yeah, but againg, me? I'm there, replace 'em if the cost is not of issue as in some cases may be. Just do not use you garden variety hardware store bolts

350-500 is kind of a wide range

BTW - my car woke up from it's winter hybernation just fine!

[Earlsfat]

Originally Posted by wrightz28

350-500 is kind of a wide range

BTW - my car woke up from it's winter hybernation just fine!

Looked up the ARP head bolts on summit... getting them in addtion to new bolts all the way around.

I though that was a wide range myself but I did ask him for a best to worst case scenario so I didn't have a friggin stroke when I went to pick them up. I figure it this way... even if it runs $500... I've got a decent shop with an excellent reputation who says they stand behind their work (and I've heard they do from other people too). If I spend $500 and the damned things will be right by the time they get done with them and I pretty much won't have to worry about them for a good long while, then $500 is worth it.

AND - just spoke with the owner... porting has nothing to do with the burnt valves in this case... thinks someone "cut" the valves and they had bad edges, which made them burn. He said, basically whoever did them the last time had an idea of what he doing, but either half assed it or rushed it, all the way from the porting to the springs. The springs and retainers don't go together, he said they also used cheap valves. All I know is that for $500 or so, they better be fucking right or they're gonna get a set of heads upside their head.

(He said that had they not been ported they would have been extremely valuable , '66 427 heads were a limited run, single year head. He acted genuinely upset! )


Glad to hear your vehicle's doing well, you bastard.