Piston ID

-
Mopower71

Mopower71

Speed Demon
Joined
May 31, 2004
Messages
2,183
Reaction score
39
Location
Poughkeepsie, N.Y.
All I have is the number off the top right now.
They are in my 340 that is .030" over
3690825 is stamped on top.
They also have 340 and .030 stamped in the top for the cubes and over size.
Been trying to find the number through manufactures, and I'm still looking.
Any help is greatly apreciated.
 
P3690825 are old Mopar Performance 11.5-1 advertised forged, domed pistons. But I don't recall them having 340 or .030" stamped on them from the factory, unless the engine builder did it.

They were very similar to versions offered by TRW and Speed Pro. But I believe those were advertised at a higher ratio. (It all depends how they were calculated based on head cc's and deck height.)
 
Thanks,
I think someone could have stamped them in.
If they did all the numers, someone has a real good eye for keeping the numbers in line and very straight. The part number on one of them is upside down though.
Seems this engine had an explosive past.
# 6 piston has a slight mark from the whole exhaust valve. And #2 has an odd mark in it, almost looks cracked, I guess I'll find out for sure when I get it out #-o
 
Ouch!

I have several pistons of the 360 version. But I'm not sure if I have any of the 340 version. I'll check around, just in case.
 
Cool, Thanks.
It will probably be a little while till I get the block ot of the car.
This is the cyl that had one of the best leakdowns with 16%.
Can't wait to pull the other head and have a peek at the one that had 62% leakage.
 
After looking a bit closer, it looks like something hit the eyebrow of the #2 piston.
#6 piston, that has the exhaust valve mark in it, also has had the edge of the eyebrow taken off by something.
 
Valves shouldn't be hitting the edge of the valve notches!
Check if the valve guides are very sloppy.
Doesn't sound good!
 
I think it swallowed something.
Are you suppose to be able to see the gear on the back of the cam, or is the block casting suppose to cover the back side of it?
 
Norman, Valves shouldn't hit the eyebrows. Usually when you see that, it has or had larger valves than what the valve pockets were machined for,(diameter). Like a 2.080 valve with a 2.020 pocket. Could have enough clearance under valve, but still be clipping the eyebrow. Terry.
 
You should see the cam gear looking down the distributor hole.
The oil pump/distributor drive gear drops down through the smaller hole next to the cam and meshes with the cam gear. The distributor shaft fits into the slotted hole in the top of it.

* Good point on possibly having bigger valves!
 
I'll get some pictures of it. No need to look down the distributor hole. It's plain as day, looking at it through the lifter valley.
 
I'll have to break out the camera again, I thought I had taken pictures of this, but I just looked and that's not in there
 
Norm, that's normal. With manifold removed, you can see the oil pump drive, distributor shaft and camshaft gear. Good luck on your new project, Norm, let us know if you need any assistance. Terry.
 
Thanks Terry,
I just looked at Mikle's photo's and it's the same.
Sure as heck looks like the piece is just broken out.
It's been a while since I had a small block apart.
I did get a good picture thru the intake manifold showing the edge.
 
Here's the #5 runner

p1130079105470.jpg
 
Norm, that is latteral miss-alignment. See if the manifold will move front to back to correct this. That's quit a bit you have there. That isn't good. Even .020 needs correcting. It causes turbulence and inequal fuel distribution problems. floor looks close. Good luck, Terry.
 
What's the casting # on the heads?

Looks like #6 cylinder lost a pushrod and the cup caught the aluminum rocler.
 
mikesduster said:
OUCH!!!!....WHY is your shafts rusted??
Click to expand...
Haven't figured that one out yet.
Also need to find out why the head has rust and water sitting between the #5 and #7 intake springs.
 
Locomotion said:
What's the casting # on the heads?

Looks like #6 cylinder lost a pushrod and the cup caught the aluminum rocler.
Click to expand...
Head casting numbers are:
253184-D
X
08058
AAWJ 340

Also looks like one on the left side of the engine lost a push rod also.
#6 is also the one with the exhaust valve mark in the piston.
 
headsbikesmopars said:
Norm, that is latteral miss-alignment. See if the manifold will move front to back to correct this. That's quit a bit you have there. That isn't good. Even .020 needs correcting. It causes turbulence and inequal fuel distribution problems. floor looks close. Good luck, Terry.
Click to expand...
Problem is, someone took a grinder to the intake manifold runners, from about 2 1/2" inside the runner and tapered out the edge. Once I get the engine all apart, I'll bolt the intake to the head without the valves in, and see if it's alignment, or to much metal ground away.
 
Locomotion, it sure does. Norm have the heads pressure checked BEFORE you do anything with them. Just make sure you have good solid cores to work with. Terry.
 
Norm, also you can use epoxy to correct the 'mess' left by someone else,s work. Easy fix, no need to get rid of that manifold. E-mail if you need assisatance and I can run you thru that. Terry.
 
You must log in or register to reply here.
-

Back
Top