ProComp/Speedmaster aluminum heads

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j par said:
My cam card says .022 lash... I usually set it at .019 cold and let it rip...
For some reason I'm thinking aluminum heads required more lash when cold??..
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I looked it up and I guess add .002 for cast iron and subtract .006 for aluminum..
Best I think I can remember Ken must have told me to set at or around .016-.017 hot...
 
j par said:
My cam card says .022 lash... I usually set it at .019 cold and let it rip...
For some reason I'm thinking aluminum heads required more lash when cold??..
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Cold lash is always tighter. Aluminum heads require tighter cold lash than iron heads. Aluminum heads and block should be lashed .015-.018 tighter cold. Then checked hot and adjusted as required.
 
yellow rose said:
Cold lash is always tighter. Aluminum heads require tighter cold lash than iron heads. Aluminum heads and block should be lashed .015-.018 tighter cold. Then checked hot and adjusted as required.
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Come on man you know I don't have no aluminum block LOL..
 
yellow rose said:
Cold lash is always tighter. Aluminum heads require tighter cold lash than iron heads. Aluminum heads and block should be lashed .015-.018 tighter cold. Then checked hot and adjusted as required.
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I dont agree, my lash is only .016 and .018 hot ! A lifelong mech. and machinist, engine builder friend told me , 006 titer lash "cold" on alum. heads .
I read that toyota said the same thing -----------------thats the way I`ve been doing it for about 10 yrs now .
I f someone followed ur advise on alum. heads ,w/ a titelash cam , they`d lose it for sure !
 
famous bob said:
I dont agree, my lash is only .016 and .018 hot ! A lifelong mech. and machinist, engine builder friend told me , 006 titer lash "cold" on alum. heads .
I read that toyota said the same thing -----------------thats the way I`ve been doing it for about 10 yrs now .
I f someone followed ur advise on alum. heads ,w/ a titelash cam , they`d lose it for sure !
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Read it closer Bob. I said aluminum heads AND block you need to lash it .016-.018 tighter cold.

Then you need to check it hot. I’ve seen some stuff need to lash at .002 cold to be at .022 hot.
 
Going to try and put motor and trans back in tomorrow.. not 100% happy with the idea of dangling the motor and that heavy trans from the aluminum heads...
 
yellow rose said:
Read it closer Bob. I said aluminum heads AND block you need to lash it .016-.018 tighter cold.

Then you need to check it hot. I’ve seen some stuff need to lash at .002 cold to be at .022 hot.
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I dont get what ur saying. I have alumn. heads, cast iron block , and set mine at .011-.012 cold , they are always right at .018 when hot . I round it off instead of worrying about a .001 or two on a .600 lift cam .
Like I said , more than one have advised that way w/ alum. heads.
I am getting ready to adjust them for the 5-6 time in 9-10 yrs, altho it doesnt have a heck of a bunch of miles on it -----------------
 
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famous bob said:
I dont get what ur saying. I have alumn. heads, cast iron block , and set mine at .011-.012 cold , they are always right at .018 when hot . I round it off instead of worrying about a .001 or two on a .600 lift cam .
Like I said , more than one have advised that way w/ alum. heads.
I am getting ready to adjust them for the 5-6 time in 9-10 yrs, altho it doesnt have a heck of a bunch of miles on it -----------------
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Ok, so your stuff grows .006-.007 from cold to hot. And that makes sense. So what I’m saying is that if you had iron heads and an iron block you would probably need to only set the cold lash .002-.004 tight to get your hot lash.

OTOH, if you took your heads and bolted them to an aluminum block, you’d probably have to lash them at .002 cold to get your .018 hot lash. That’s because the aluminum block grows so much more than an iron head.

That’s what I’m saying. Somehow, Harvey Crane OE someone else have published that when setting cold lash with an iron block and heads you set the lash at .002-.004 LOOSE cold and when the engine gets hot the lash will close up.

I can tell you that is 100% wrong. I’ve not seen any cast iron head, cast iron block ever LOSE lash from cold to hot. Ever. So for starting out on cold lash I always say:

Cast iron heads and block set the cold lash .002-.004 tighter and then check what your hot lash is and adjust accordingly.

Aluminum heads and cast iron block cold set the lash .004-.006 tight cold and check your hot lash and adjust accordingly.

Aluminum block and heads is a bit more tricky because of the mass of the block. I say start at .010-.012 tight on cold lash and check the hot lash and adjust accordingly.

Ive seen aluminum heads and blocks grow .020 or more. The all aluminum hemi seemed to grow more than the all aluminum wedge stuff.

I hope that makes sense.
 
j par said:
Going to try and put motor and trans back in tomorrow.. not 100% happy with the idea of dangling the motor and that heavy trans from the aluminum heads...
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Don’t you have a scatter shield? I’ve never been able to stick a engine/trans together when there is a big scatter shield on there.

As long as you have at least one times the diameter of the bolt into the threads on the head the aluminum will hold much more than the weight of the engine/trans.
 
yellow rose said:
Ok, so your stuff grows .006-.007 from cold to hot. And that makes sense. So what I’m saying is that if you had iron heads and an iron block you would probably need to only set the cold lash .002-.004 tight to get your hot lash.

OTOH, if you took your heads and bolted them to an aluminum block, you’d probably have to lash them at .002 cold to get your .018 hot lash. That’s because the aluminum block grows so much more than an iron head.

That’s what I’m saying. Somehow, Harvey Crane OE someone else have published that when setting cold lash with an iron block and heads you set the lash at .002-.004 LOOSE cold and when the engine gets hot the lash will close up.

I can tell you that is 100% wrong. I’ve not seen any cast iron head, cast iron block ever LOSE lash from cold to hot. Ever. So for starting out on cold lash I always say:

Cast iron heads and block set the cold lash .002-.004 tighter and then check what your hot lash is and adjust accordingly.

Aluminum heads and cast iron block cold set the lash .004-.006 tight cold and check your hot lash and adjust accordingly.

Aluminum block and heads is a bit more tricky because of the mass of the block. I say start at .010-.012 tight on cold lash and check the hot lash and adjust accordingly.

Ive seen aluminum heads and blocks grow .020 or more. The all aluminum hemi seemed to grow more than the all aluminum wedge stuff.

I hope that makes sense.
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Way better explanation !
 
j par said:
Yes BUT, what percentage of us have aluminum blocks in our abody Mopars?
Yellow knows I don't...
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Many more aluminum big blocks than small blocks. And then when you work with blown stuff that’s all you see. I had a customer that had an all aluminum SBC. Pretty nice piece. He had 300 passes on his aluminum rods and I told him you are on the head of a pin. They needed to be changed. He pushed it and 10 or so passes later a couple let loose. It blew the front two cylinder off the rest of the block. Lost everything but the heads, and his repair bill to me was several times what a new set of rods would have cost him.
 
Back in ..
:thumbsup:

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Oops... Hit the wrong button...
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Let me take this moment to thank my beautiful kind great assistant! She has probably put in and out more Motors then 3/4 of the people on this forum likely... Nothing like having a caring assistant who really watches out and makes these things go much easier. Someone with experience... And now I will take a break and eat the roast beef sandwich she just made me...
JPar's wife is the greatest!!!..
 
j par said:
Oops... Hit the wrong button...
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Let me take this moment to thank my beautiful kind great assistant! She has probably put in and out more Motors then 3/4 of the people on this forum likely... Nothing like having a caring assistant who really watches out and makes these things go much easier. Someone with experience... And now I will take a break and eat the roast beef sandwich she just made me...
JPar's wife is the greatest!!!..
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Are those her Jeans.
 
Those DC valve covers look even better next to those ceramic coated headers..

My wife used to help me too, until the boys could walk, then they had to help me. She still cooks good suppers though!
 
Does your engine tilter still have the crank handle? I took mine off and welded a nut on so I can use my 1/2 inch air impact to tilt it. Lazy man's way.
 
Mopar Sam said:
Those DC valve covers look even better next to those ceramic coated headers..

My wife used to help me too, until the boys could walk, then they had to help me. She still cooks good suppers though!
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The covers are still all dirty... I ran the oil pump to both sides before I took it off the stand because if I had any issues I wanted it out of the car LOL I tried to tilt it side-to-side and get as much strained back as possible but still when I put it on the chains it poured off the back so I had to put the valve covers on. I'll get them back off and get them cleaned up. I used some rim cleaner on the tunnel ram autumn and it came out pretty clean. I painted the black timing cover silver...
More improvements on the way... I ordered a set of cvf racing pulleys and the alternator bracket.. I'm also ditching those two 12in motorhome fans that I've been running for 3 years now and have a nice 16 in fan coming tomorrow...
Fancy schmancy....
 
Mopar Sam said:
Does your engine tilter still have the crank handle? I took mine off and welded a nut on so I can use my 1/2 inch air impact to tilt it. Lazy man's way.
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know that fell apart or broke off and now I just have the 4in piece sticking out and I always forget to lubricate it before I use it so it's almost useless. I just have it all aiming down words and get the floor jack under the tranny and work it back up as it goes in...
 
j par said:
know that fell apart or broke off and now I just have the 4in piece sticking out and I always forget to lubricate it before I use it so it's almost useless. I just have it all aiming down words and get the floor jack under the tranny and work it back up as it goes in...
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Well you have a welder... If you have an impact you ought to weld a nut on it, works great for me. I thew that crank handle away the first time I used it!

Anyhow, glad you are getting it done. I have been too busy to work on anything I WANT to.
 
Years ago some of the best sex was in my shop while working on the race car back when I was married. My deer hunting tree stand in my yard was pretty good too.
 
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