would a 1985 slant six head work on an earlier block ....say 73
are there any concerns with parts so new as 1985?
are there any concerns with parts so new as 1985?
late model slant six head
- Thread starter Princess Valiant
- Start date
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1970Dart198
Well-Known Member
I'd say you'd be fine. I know Slants came with Hydraulic Valves in the 81'-85' years. On a 73 engine you'll need mechanical valves. The heads will work, just convert it over.
1970Dart198
1970Dart198
pishta
I know I'm right....
Dont see why not, actually has the better plug mounts. Trying to think if the rocker arm oiling would be any different, probably not. Get valve cover too.
the head is going to cost like 50 bucks and the whole engine like 300
I cant justify that much bread for the whole engine since it has the wrong pan and I don't really need the whole thing anyways .......I just need a later style head if it will fit on an earlier block.
I cant justify that much bread for the whole engine since it has the wrong pan and I don't really need the whole thing anyways .......I just need a later style head if it will fit on an earlier block.
Heads are all interchangeable, valves are not Hydraulic, lifters are. The lifters,pushrods,and rocker arms on hydraulic adjuster engines are completely
different. The system actually oils the hyd. lifters "backwards" from the rocker
shaft, through the rocker arms, and down the pushrods which are hollow, into
the lifter through the pushrod cup. It works, odd as it is,and was neccessary
because there is no oil passage to the lifter bores.
Dot.org has the run down on the combustion chamber changes, later heads
w/the external spark plugs all have the more desirable chamber, tho' they are
a good 12 to 15 lbs. heavier. Either way, you're good to go on your swap, just
make sure you use your valvetrain if that engine happens to be hydraulics.
Cheers!!:coffee2:
P.S. valves were same 1.62/1.36 pair for the 30 yrs. of production regardless of lifter type,
same for the rocker shaft.
different. The system actually oils the hyd. lifters "backwards" from the rocker
shaft, through the rocker arms, and down the pushrods which are hollow, into
the lifter through the pushrod cup. It works, odd as it is,and was neccessary
because there is no oil passage to the lifter bores.
Dot.org has the run down on the combustion chamber changes, later heads
w/the external spark plugs all have the more desirable chamber, tho' they are
a good 12 to 15 lbs. heavier. Either way, you're good to go on your swap, just
make sure you use your valvetrain if that engine happens to be hydraulics.
Cheers!!:coffee2:
P.S. valves were same 1.62/1.36 pair for the 30 yrs. of production regardless of lifter type,
same for the rocker shaft.
Kernel Sanders
eating chicken wings and drinking beer
I did see it mentioned but want to restate... take the valve cover as they are different for the newer 'peanut' heads from the 'drool tube' heads
OH! there is an air injection port right behind the #6 cylinder that will have to be blocked either by tapping a plug or fabricating or getting a block off plate. Dodge does have a part number for this... Gasket pn 4275834, Plate pn 3751249
OH! there is an air injection port right behind the #6 cylinder that will have to be blocked either by tapping a plug or fabricating or getting a block off plate. Dodge does have a part number for this... Gasket pn 4275834, Plate pn 3751249
BillGrissom
Well-Known Member
$300 for a used slant is humorous. They would surely giggle once they had your money.
Later engines (~1980?) had a different size bolt hole at the rear rocker shaft. There was a special undercut bolt in that hole. Some thought it was for oil supply, but others said it was so the rocker shaft couldn't be installed wrong. I don't know if the tapped hole in the head varied. Anyway, read up. I don't know if anyone has installed the later hydraulic valve train in an early engine, if you desire that. I recall talk of having to drill an oil hole in the block or head. Probably less risk to stay w/ solid lifters & rockers.
Perhaps the biggest downside of the later heads is that you can't remove the lifters without taking the head off. Main upside is no more spark plug tubes to leak oil, though those are a tie to the 426 Hemi.
Later engines (~1980?) had a different size bolt hole at the rear rocker shaft. There was a special undercut bolt in that hole. Some thought it was for oil supply, but others said it was so the rocker shaft couldn't be installed wrong. I don't know if the tapped hole in the head varied. Anyway, read up. I don't know if anyone has installed the later hydraulic valve train in an early engine, if you desire that. I recall talk of having to drill an oil hole in the block or head. Probably less risk to stay w/ solid lifters & rockers.
Perhaps the biggest downside of the later heads is that you can't remove the lifters without taking the head off. Main upside is no more spark plug tubes to leak oil, though those are a tie to the 426 Hemi.
Stick with the drool tube head. I never had issues with them leaking because I kept my stuff maintained. That's all you gotta do.
The valve cover IS different on the later truck heads. Those heads are bastard children. You don't want it.
The valve cover IS different on the later truck heads. Those heads are bastard children. You don't want it.
Charrlie_S
Well-Known Member
You must run the correct valve train (rocker arm, rocker shaft and pushrods for the engine), whether solid or hydraulic. The head itself doesn't matter.
They made peanut plug heads with both styles of valve cover. 75-ish-80 took the same valve cover gasket as the 60s/Early 70s ones did
I put a 77/78 vintage peanut plug head on my 74 block no issues.
As far as I remember reading the combustion chamber on 68+ are all the same but different from 67 down. And supposed the 68+ are better ones in that department
I put a 77/78 vintage peanut plug head on my 74 block no issues.
As far as I remember reading the combustion chamber on 68+ are all the same but different from 67 down. And supposed the 68+ are better ones in that department
I believe the cam is part of this equation as well. A hydraulic cam has a groove in the rear journal that has to do with oiling. A solid cam does not. I put a solid valve train in a hydraulic head, and I remember having to regrind a solid cam as well.
My disclaimer, and other experts please jump in here if needed. I did this swap a while ago and may be fuzzy on the details, but I think this is right.
Charrlie_S
Well-Known Member
That was what I said. The valve train must match the engine, not the head. If hydro engine, hydro valve train, if solid lifter engine, solid lifter valve train. The hydro cam does have the groove, where the solid cam does not. But if you are just swapping the head, the cam is out of the equation.
Don't forget if you run the hydraulic head, the valve cover is specific to that head. The solid lifter valve covers will not fit.
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