wanab03ss

iTrader: (20)

The motor only has 6-8k on it and @ 30 passes. Its bored .040 and stroked. An intake valve spring broke and the valve dropped into the cylinder wall, is there anything I can do besides having all the cylinders bored to .060?

IROC-You

get another block and bore it .040 over, this will allow you to use the same pistons and not have to get new ones.

wanab03ss

iTrader: (20)

Alot of money and time were put into this block, all 4 main oil drain back holes were opened up and polish, lifter valley drainback holes were tapped for threaded plugs, front and rear freeze plugs were tapped, its a 4 bolt main 1 piece rms, block clearanced for stroker, rear main cap ported n polished for oil pump. everything deburred and champerd, bored,decked, torque plate honed, file fit rings. All this done @6k ago. I really dont want to get rid of this block.

Apeiron

Well, if going to .060 doesn't fix it, then that can all be done again on another block.

wanab03ss

iTrader: (20)

Is there anyway to go .060 on one cylinder. As far as weight goes would it be hard to get this one rod n piston to match to the other ones?

84 z28

Could you put a sleeve in that cylinder ?

IROC-You

take a finish hone to it and see how bad it is and remove any sharp edges. You may be able to run it after the finish hone. Sure you will have a little blowby there but as long as the rings dont catch you should be good.

wanab03ss

iTrader: (20)

there smooth, no sharp edges I noticed when running my finger across it.

Apeiron

A sleeve is a better idea, and not terribly expensive.

wanab03ss

iTrader: (20)

How exactly do they sleeve it? Any idea on cost or what to look or ask for?

Apeiron

They bore the cylinder completely out, put a sleeve in, then deck the block and bore the sleeve out and hone it to the final size. Some people don't like using them, but there's no real problem with them when they're done properly. I have a cylinder sleeved in the block in my 84. The last I checked, it runs around $50 a hole or so.

wanab03ss

iTrader: (20)

Just called alocal machine shop, 120$ labor and $40 for the sleeve

Apeiron

Compare it with the price of doing all that work again on a new block.

fwb35

Sleeve the cylinder, I did it in a race block I had and nevr had a problem

ShMaCk2004

LS1's are sleeved

Apeiron

All aluminum engines are sleeved.

wanab03ss

iTrader: (20)

Just got off the phone with a few more shops,,, If I have to have it sleeved the entire block has to be torn down freeze plugs and all, hot tanked cleaned, so they have to replace cam bearings, the cheapest Ive found its going to cost 400-500 to have it sleeved with everything else thats needed...... Screw it, its going it the car and maybe down the road Ill get a new block.

five7kid

iTrader: (14)

Not the Vega.

I'd go along with the hone idea. Don't use a ball glaze breaker, use a flat stone type. Go over it by hand first to remove the high points, the a quick back & forth to give it a cross hatch. DON'T hone the entire cylinder to remove the marks completely, all you want to do is get rid of the metal that has been displaced out of the wall.

Blow by should be minimal, but probably won't be zero.

I have heard of people going more over on one cylinder than the others. You'd want to make sure the pistons are equal weight, though. You're talking about 0.45 more cubic inch in a 0.060"-over cylinder than a 0.030"-over cylinder.

1986Z28OWNER

iTrader: (1)

sleeving a stock block isnt a god idea, especially in a perf application, try taking it to 0.060" it it dosnt clean up, its a boat anchor id say

GXR11

id like to know more on why some people say its not a good idea to sleeve a stock block.(other then potentially dissimilar metals and thermal expansion) a good friend of mine had to sleeve a #8 bore from a air cleaner stud some how making it past the valve. either way, he never had a prob with it. he paid $125 to have it done... (just dropping off the bare block to the machine shop)

if i was in the OP's shoes, id just re sleeve it

tom3

With that damage up high in the cylinder I suspect it needs to be bored. Down lower it wouldn't be so bad, two stroke engines have huge holes in the cylinders and run a long time at super high rpms. If failure wouldn't really upset you I'd say put a set of rings in it and see what happens.

wanab03ss

iTrader: (20)

Failure? Ill get blowby I wouldnt call that failure..... Im just going to put a bottle of Zmax in it,

fwb35

We sleeved a engine we raced for a whole season at over 7,000 rpm, never had a problem, re sleeve it.

84 z28

Just like Apeiron said aluminum engines are sleeved and almost all of them are performance apps. I would sleeve it .

wanab03ss

iTrader: (20)

Im not spending 400-500$ to sleeve an engine that has 6k miles on it. since its last time to the machine shop. Just dont have money in the budget for that right now. A very light stone hone in that area should take anyhigh spots out and itll run just fine I think.

Apeiron

I agree, it's at the top of the stroke where the piston spends the most time and cylinder pressure is highest.

Apeiron

And from that experience it was discovered that it's easier to put sleeves in than it is to control the metallurgy and multiple layers of platings necessary to run an unsleeved aluminum block.

five7kid

iTrader: (14)

Porsche 928 V8's, aluminum block, no sleeves or liners.

Knock the high spots off of those dents, I'm betting you wouldn't be able to tell that cylinder was "different". Might not be what you want for an all-out high-HP engine, but I haven't heard what this engine is being used for yet.

wanab03ss

iTrader: (20)

Its a sunday driver that will probally go to the track 2 or 3 times a year.

five7kid

iTrader: (14)

Stroked 305?

wanab03ss

iTrader: (20)

No, its a 385 with cast steel crank and forged rods

articwhiteZ

iTrader: (56)

Look..whats done. is done..

if you cant feel anything with your fingernail.
or if it's just a lighty there. i would just take it down by hand. Like five7kid posted

till it feels and looks good. and put it back together. and run it.
it will not. hurt anything.. within 2 more years. it will all be the same.
it spends it's time in that spot for less the a milla sec. and half of that..

your fine.. the worst part is knowing it's there...lol
(by the way ..thats nothing!)

put it back together and have fun..

the big thing is, why are your springs FALLING APART??
WITH 6000 to 8000 miles on them??

wanab03ss

iTrader: (20)

My springs didnt fail, the previous owners did. It was in a mid-high 10sec street car pushing 500hp N/A with a 150 shot on top of that. Not to mention 20-30 passes at the strip in 2 years since it was built

articwhiteZ

iTrader: (56)

well what ever it was that got one to snap..

i would just finnish and tweek the cylinder by hand and put it back together.. you will be fine.. with all the time it has on it. it will never show anything wrong from that itty bitty gooff.. it will be fine.