FWI the Mr. G head gasket part # is 1121g , but I myself prefer your "option 1" for what to do.
Almost time for the machinist!
- Thread starter dartfreak75
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dartfreak75
Restore it, Dont part it!
My heads are open chambers 360 heads they cced at 70-72 I'm calling it 71 so removing .020 will put me at 67 .025 will be 66 and .030 will be 65. Or somewhere around that. I'm gonna install my new valves and re cc just to double check and triple check before I tell him exactly how much to cut.
My pistons are speed pro h116cp they are flat tops with +5 cc eyebrows and will be .027 under the deck.
My pistons are speed pro h116cp they are flat tops with +5 cc eyebrows and will be .027 under the deck.
dartfreak75
Restore it, Dont part it!
Did you have to use shorter push rods by cutting .030?
I got different pushrods. Just to get the rocker geometry to come out right.
nm9stheham
Well-Known Member
Probably not.... that is on the margin of being OK, and you will just have to check the lifter pre-load at the end and see what it is.
???? Not seeing how that changes rocker geometry unless:
- Valve length changes, or
- Rocker shaft position changes
dartfreak75
Restore it, Dont part it!
He Is using adjustable rockers. Maybe that's the difference?
If you mill the heads you need longer push rods.
I think that may have been the case. I didn't measure the new valves and I bet they were different length than the originals. The lifters were not the same as the original dumbells either. The rockers were way off and I bought longer pushrods and had to shim the shafts as well. Tolerance stacking!
Wyrmrider
Well-Known Member
just read through this thread
the grove in the bushing is for oiling the gear- good idea
YMWV on the rocker geometry
but if heads are stock unmilled now and valves are same length and cam base circle is stock small mill should not require new pushrods-
hyd lifter will take up the difference and NOT change the geometry
just measure the depth on each end chamber then mill flat to get them all four ends the same
the middles are what they are
If the heads have been cleaned up on a belt sander by a quickie rebuilder previously they will take a lot of milling to get them back square do check with a deck mike- they are cheap and an essential toolbox item
as others have said check the block then bore as little as possible- if no rust MOPAR (and AMC) blocks are tougher than brands X
how much ridge?
how do you clean the oil gallies without taking all the plugs out?
detail your oil system first
drill the main feeds to 9/32
I have found broken drill bits and partially drilled holes ( from too many sharpening/ shorting bits at the factory)
clean up any roughness and round your corners
square corners kill flow (turbulance)
bottom tap alll your bolt holes
you did your porting so you can do this
Why not the KB quench dome pistons
they were designed especially for your heads and they really work
the grove in the bushing is for oiling the gear- good idea
YMWV on the rocker geometry
but if heads are stock unmilled now and valves are same length and cam base circle is stock small mill should not require new pushrods-
hyd lifter will take up the difference and NOT change the geometry
just measure the depth on each end chamber then mill flat to get them all four ends the same
the middles are what they are
If the heads have been cleaned up on a belt sander by a quickie rebuilder previously they will take a lot of milling to get them back square do check with a deck mike- they are cheap and an essential toolbox item
as others have said check the block then bore as little as possible- if no rust MOPAR (and AMC) blocks are tougher than brands X
how much ridge?
how do you clean the oil gallies without taking all the plugs out?
detail your oil system first
drill the main feeds to 9/32
I have found broken drill bits and partially drilled holes ( from too many sharpening/ shorting bits at the factory)
clean up any roughness and round your corners
square corners kill flow (turbulance)
bottom tap alll your bolt holes
you did your porting so you can do this
Why not the KB quench dome pistons
they were designed especially for your heads and they really work
LOL
Actually shorter. Hydraulic lifters will never know. Solids usually not either unless you change a bunch of stuff.
Wyrmrider
Well-Known Member
I Ignored that
maybe he had a small base circle cam
to do it right you have to do the mid lift procedure then order pushrods - stock OR adjustable rockers
adjustable rockers have to have a really short distance from the ball to the rocker to work right
and did we mention oil through the pushrods? the 2011 lifters already provide oil and hollow pushrods with drilled ends help with rocker cup wear
you can also buy a 229 chev v 6 lifter and copy the grove on the side
just chuck your lifters in a v block on a magnetic chuck grinder and make a 3/32 (or so) wide flat spot- oils the cam - there is a picture in the johnson lifter catalog
do do all your block detailing B 4 machine shop
maybe he had a small base circle cam
to do it right you have to do the mid lift procedure then order pushrods - stock OR adjustable rockers
adjustable rockers have to have a really short distance from the ball to the rocker to work right
and did we mention oil through the pushrods? the 2011 lifters already provide oil and hollow pushrods with drilled ends help with rocker cup wear
you can also buy a 229 chev v 6 lifter and copy the grove on the side
just chuck your lifters in a v block on a magnetic chuck grinder and make a 3/32 (or so) wide flat spot- oils the cam - there is a picture in the johnson lifter catalog
do do all your block detailing B 4 machine shop
I've actually had several heads cut - up to .045 and never cut an intake or changed pushrods. Never had a issue either. These factory casted blocks and heads are all different from the factory, yet all got the same intake and pushrods. Remember, the factory tin head gaskets were even thinner than a .028 Mr Gasket.
Not that it's bad to check the intakes/push rods, but I wouldn't bother on anything .030 or less.
Not that it's bad to check the intakes/push rods, but I wouldn't bother on anything .030 or less.
Around .018
Wyrmrider
Well-Known Member
It's all about tolerance stacking with 50 year old parts
if valves are sunk pushrod theoretically shortens by 2/3
larger valves and higher seats just the opposite
just put it together and see if there is some play when you push the pushrod down
not a race car or fast action cam you are good to go
then cut the tops off a couple of old valve covers and observe lifter rotation and oiling,
you can do the oiling check when you spin the oil pump with a drill IF you have the oil holes in the cam lined up - rotate the crank slowly with a breaker bar and observe- remember cam is at half speed of crank so you might have to go around twice to hit oil- if you do not hit oil then find out why before you fire the motor
if valves are sunk pushrod theoretically shortens by 2/3
larger valves and higher seats just the opposite
just put it together and see if there is some play when you push the pushrod down
not a race car or fast action cam you are good to go
then cut the tops off a couple of old valve covers and observe lifter rotation and oiling,
you can do the oiling check when you spin the oil pump with a drill IF you have the oil holes in the cam lined up - rotate the crank slowly with a breaker bar and observe- remember cam is at half speed of crank so you might have to go around twice to hit oil- if you do not hit oil then find out why before you fire the motor
nm9stheham
Well-Known Member
Unfortunately, with all the tolerance stack-ups as mentioned, no one can guarantee that a head cut of .030" won't end up with pushrods too long. So cutting heads 10 times and not having an issue does not say if there will be issues or not on #11.
The above says why: different parts and different stackups. The same pushrods worked at the factory only because the nominals were the same and the worst case stackups were designed to work 99+% of the time. Once you cut the heads .030", you are well outside the factory nominal for head height and all bets are off.
As a design engineer in a past career, working with volume production designs and tolerance stack-ups, trust me.... Usually you are fighting to keep the fall-out to a minimum with standard parts tolerances, and costs make you loathe to spec tighter part tolerances. Put in a large variation like -.030", forget it; you are going to get some fair % of parts combinations that are not going to work together. That is why I don't agree with the idea of ever telling folks that they 'should not bother' on this particular matter.
that .030 becomes .020 if you use the Mr G thin gasket. That .030 becomes 0 if you use the "over the counter" fel pro from the parts store. So, you missed that in your assessment. By the way, we machine transmission parts to the micron, usually with a .012 +/- tolerance. Again, a micron is a thousands of a mm, not an inch. So I know a thing or two about tolerances.
again, not a bad idea to check it all. But I just check by eye and feel...
dartfreak75
Restore it, Dont part it!
My piston choice was based on two things. One the factory weight pistons so I dont have to spend a boatload of money on rebalancing the engine. I did alot of research and homework to find a piston that weight the same as the factory one (within 2 grams @ .030 over) and give me my desired scr.
Which brings us to reason #2 compression I wanted a cr that I could run on pump gas without worrying about additives or quench or anything like that so with my cam choice I to keep my dcr around 7.5-7.8 I came up with 9.5. This piston will achieve that with a aftermarket felpro headgasket [thick] with as little as 0.025 of the heads
The kb pistons couldn't give me that. Yes they will probably give me more power but at alot higher cost!
dartfreak75
Restore it, Dont part it!
I got the distributor drive bushing out and I was wrong it does have the groove in it.
Another question.
Do I need to remove all the old gasket material from the block before taking it or does the cleaning process remove all that too?
Another question.
Do I need to remove all the old gasket material from the block before taking it or does the cleaning process remove all that too?
Clean it/leave it, doesn't matter in the over all scheme of things.........if the shops method of cleaning is to bake and shot blast, the block will look like a brand new piece of iron, chemical dip will lift anything stuck to the block...........however, you could look upon the removal of goobers/crud/etc as one more chance to inspect the block just to make sure there are no surprises.
If you haven't already, you can take this time to knock out/remove all soft plugs/oil gallery plugs so you have an idea of what goes where when you put the new ones in.
If you haven't already, you can take this time to knock out/remove all soft plugs/oil gallery plugs so you have an idea of what goes where when you put the new ones in.
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dartfreak75
Restore it, Dont part it!
I was mostly worried about it causing him more work and time and in return costing me more money in labor. Yes I'm that cheap! Haha
nm9stheham
Well-Known Member
Scrape off all you can so the chemicals will be able to work at it sooner.... I am sure it will be appreciated, just as I am sure the chemicals will eat that stuff up, along with the paint. FWIW, I have never had a shop bead blast a block... it just is not commonly done in my neck of the woods.
dartfreak75
Restore it, Dont part it!
I didn't ask him his procedure for the cleaning process I guess I should have. When i asked him about the bore he said he does it in a package cleaning bore hone and cam bearings for 450 I said I would do the cam bearings myself and he said 350! Then approximately another 100 for the heads so I'm looking at about 500 or so
dartfreak75
Restore it, Dont part it!
That's a beautiful engine Mike! Is the 273 in your gold dart or your swinger? IIR the blue swinger has a 318 correct?
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