My oil burning pig. Pics too!

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If your driving it around on the street.more, you may want to unlock your distributor and get a 10* advance bushing. Driving at low rpm with locked out timing isn't good. Low cylinder pressure with increased temp.due to timing can cause preignition type issues.

Just a thought. And I am guessing you have a MSD distributor....
 
That looks like it. I thought you said you fixed that ;) ?
When you mill the heads on a small block it should be .010 to .009 (head to intake sides). Personally I use 1:1 for big and small blocks when I mill heads.
 
It looks like your gasket did not match the port very good.
Try a different brand gasket, summit lists port sizes on their website.
 
I've been going through a situation with the decking on the block not being square to the bores due to poor machining. If the block deck is sloped so that the angle is even just 0.1 degrees less then 45 degrees, then the deck and intake surfaces on the head can be square to each other (a perfect 90 degrees), and the intake surfaces can be at a perfect 90 degrees to each other, but there still will be a bit of a gap at the bottom of the intake gasket area that the intake gasket can't make up. A gap opens up at top if the deck surfaces are slightly over 45 degrees.

So, if the block decks are not at at essentially a perfect 45 degrees L & R, or the heads' bottom surface not milled true with an exact 90 degree angle to the intake gasket surface, you can easily get a few thousandths of extra space at the bottom (or top) edge of the intake gasket surface. It looks like your intake gasket surfaces needs to be slightly angled milled to take a bit more off the upper edges than the lower edges. The .009 to .010 milling ratio does nothing to fix an off-angle.
 
Yeah Mope, thought I fixed that. Jeez! Well it's at the machine shop now. Looks like either the decks weren't done precise or the heads werre milled askew. My machinist had me give him a bunch of measurements and wer're pretty sure he can do a "compund cut" on the intake to get things squared up.

Probably gonna need a thicker gasket, he said Cometic will cut 'ya one any size you need.
Port alignment wasn't so good either. I'm not sure if I MIGHT have 2 different thickness gaskets when I'm done.....

Far as timing, I would like to try a 10 degree bushing in my MSD distrib, but can't remember what member here was making them. With timing locked it is "sloppy" below 2500 RPM. Spits, farts, etc.....2500 to 7000, though you best be holdin on! All the crap I've been through with this thing I forget that

1: you could park it on a white living room rug.
It don't leak, weep, or seep anything. AND it runs cool.

And 2: It did make a LOT of HP on the dyno. A dyno that the owner says is a bit "stingy". Just wanna get this intake thing right and call it a day.

I'm tired!
 
nm9s - what you're seeing as off angle I'm seeing as the intake is too fat for the valley. Make it thinner and there will be crush on the bottom of the gasket. That's assuming all the ports have that same issue. If the issue is apprent only two ports of four on one side, or only all four on one side but the other's fine, the I'd agree it's an angle issue too.
 
Yep. It was an angle issue AND a width issue. Finally I got a machinist who really knows his stuff.

Looks like a perfect fit now............finally. I have to scrounge .080 gaskets though. Gonna give Cometic a call Monday.

Hope the end has finally come to this friggin nightmare.
 
moper said:
nm9s - what you're seeing as off angle I'm seeing as the intake is too fat for the valley. Make it thinner and there will be crush on the bottom of the gasket. That's assuming all the ports have that same issue. If the issue is apprent only two ports of four on one side, or only all four on one side but the other's fine, the I'd agree it's an angle issue too.
Click to expand...
If the head and intake angles are mismatched all across one side or the other, then just shaving the manifold at the existing surface angle won't close that resulting gap at all. The plane of the intake and head surfaces should theoretically be an exact 45.0 degrees from a vertical plane through the engine; if not, they should be matched to at most 0.1 degree tolerance, probably less; every 0.1 degree off of a perfect angle match results in about a .0035" gap opening at top or bottom.

OP, hope you have the solved! What a saga.....sounds like you should do the standard checks of the intake manifold fit with feeler gauges and clay. Seems like we could all use the equivalent of Platigage for manifold fit checking to check gaps all around.
 
if it was pulling oil from the lifter valley ( not sealed correctly ) it would have a vacuum leak and would run like it had a vacuum
 
Well guys... I've had enough. Gonna yank the engine this weekend and have the heads thoroughly checked and re ring it with conventional rings, after a honing.

In addition, I am not running that cam again, either. Sumpin "fishy" with it also.

It's been a terrible season for me and I refuse tho go through this next year.

I'm actually hoping I can find SOMETHING wrong....
 
Sorry about your level of frustration. You've got some time to find a decent place to fix it.
 
Thanks Mope. Yeah. PLENTY of time. Before ya know it, we'll be shoveling snow. If I could find the right place, I'd love to just send the whole works off...say "Here. Fix this, dyno it, and ship it home".....I'm THAT fed up with it.
 
A lot of people would have just sold the heap in frustration. At least you're not givin up. Good for you.
 
I bet its the valve stem guide seals leaking and with no PCV in it the crankcase gas pressure is helping push the oil out the leaky valve stem guide seals.

VERY possible the machine work was done and done over sized, (machinist DO make mistakes) so. they're as human as you or I and or the rest of us here. SO.....

Get a PCV system going, could the crankcase pressure be forcing the oil? (I'm not sure of that one!) BUT is it possible that could be aiding the oil leak?
 
intake machining did not help. You CAN now tell that it fits and seals well.

I run header evacs that keep the crankcase at around 5 inches vaccum. PVC won't help.
 
Thanks for the answer on the intake, despite all the frustrations. Sealing better is a good step.

The one thing about the evacs vs PCV to know: The intake manifold and intake runner pressure is waay below the evac pressure under the valve cover any time you are below full throttle, so any seal or guide leakage will still occur. A PCV will do a better job of equalizing the pressure between intake runners and under the valve covers, so will do a better job of lowering any leakage. So it is not solid thinking that the evac will do as good a job. If you spend a lot of time at cruising and other non-WOT conditions, where the PCV is active, the PCV will doubtless do a better job.....(edit to add:) largely because it equalizes the pressure above and below the seal and guide.

But, the evac should be better than no crankcase venting system. And the PCV is not active all the time, like at WOT, which is where the evac will still be working. Evac's are quite appropriate for racing conditions where the engine is at WOT conditions a lot.

Not trying to preach at anyone, just explaining the difference. Sounds like examining the rest is a good next step in your case. I sincerely hope this gets all cured and you have a good report next time.
 
" the evac should be better than no crankcase venting system. And the PCV is not active all the time, like at WOT, which is where the evac will still be working. Evac's are quite appropriate for racing conditions where the engine is at WOT conditions a lot."

True 'dat.
The PCV is most effective at idle and decel when the intake vacuum is greatest. The evac system is strongest at WOT when the flow around the valve's siphon is greatest.
 
The heads are now at JP Precision getting a thorough check. He doesn't feel it's guides. If they ARE shot, they all went south on the dyno. Kinda hard to fathom, but possible. If that's the case, I have a HUGE geometry problem. I guess even though my "scrub pattern" looked good, I could still have an issue.
He's gonna pressure check them and every other check he can do.

Popped out a piston today and as I thought my rings are installed properly. BUT...seems to me the oil rings have hardly any tension at all. With the piston out, it looks like they are already compressed....if ya get what I mean.

Bores look great. Still see the crosshatch, no scratches etc. But they all seem a bit brown tinged, colorwise. Maybe they're glazed? I don't know.

Anyhow, I thought I'd keep you guys updated until I get to the root of this problem.

By the way, I appreciate all the input and suggestions!
 
Well, the oil rails (the upper and lower thin parts of the oil rings) don't typically have much tension by themselves; the oil ring spring behind them is what puts the pressure on the rails. So make sure you are looking at the whole oil ring assy, not just the rails. Make sure the oil ring spring ends have not overlapped. That will take all the pressure out of them; and you usually need to replace the springs if that has happened.

Look at the 2nd rings and see if they are oriented up correctly; either a dot or some marking. 2nd oil rings usually play an important role in oil control.

Check all the ring side gaps in the grooves.

Brown sounds OK. Glazed is smooth and shiney, almost mirror-like.
 
Ironmike said:
Bores look great. Still see the crosshatch, no scratches etc. But they all seem a bit brown tinged, colorwise. Maybe they're glazed? I don't know.

Anyhow, I thought I'd keep you guys updated until I get to the root of this problem.
By the way, I appreciate all the input and suggestions!
Click to expand...

Well Sir, Myself & a few of My 'psychotic gearhead buds' have been following this thread
with piqued interest... I will send You a bill for the mass quantities of beer consumed... :D

Errr....mmm... Doh! where was I?
Ohh...
Could I impose for some H/D pics of the bores ???
if 'doable' Thx ! oh, & the piston skirts Thx x2 !
 
Oh yeah, I got updates.... 1. the cnc porting broke thru the valve cover screw holes. Knew that the day I got 'em, was told to put a little silicone on.....no big deal.

At the local head shop he found even when sealed with silicone, Loctite thread sealer,,,,,they were still pulling oil like crazy. And there was intake crossover mix up between the ports also. This explained the off idle miss I could NOT get rid of.

Epoxied up real nice now, pressure and vacuum tested and he even flowed 'em for me.

2. The BIG culprit was a horrible hone job last winter. When I refreshed this thing then, I had a local shop give it a quick hone. Looked good to me.

What happenned was their honing stones were broken, or something was stuck in them, so they ran a flexhone(dingleball) thru there to cover it up.

When my new, really good machinist saw the bores a couple weeks ago he knew immediately what happened. My friggin bores looked like they were threaded.

So now I'm .060 over with a great sonic check and beautiful hone job. I KNOW my heads are ok and my intake is cut properly. Been a rough friggin road getting to the bottom of this and I kinda knew I'd have to tear it apart and rebuild.

The decks were all over the place so it had to be decked, too. You'd think that should be done on the very first rebuild..

I hope to be back on the dyno soon. Still wavering on cam choice.

Oh.Yeah. No more Gapless rings for me. Probably not an issue but never ever again.
 
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