The Jalopy Journal
Discussion in 'The Hokey Ass Message Board' started by tunescape1, Oct 13, 2009.
can you put 241 hemi heads on a 325 block? i really need help on this
I can't help but I know this has been discussed I think. Try the search...
Try Dodge Hemi Interchange in search. Is this that deal with the 241 that needs a rebuild and the 325 short block? Make sure that short block is a hemi, the pistons are different, you might bang them off the valves if they're poly.
I can tell you that the 241 heads will bolt to '55 Plymouth 241 and 259 poly V8s, which are the only year the Plymouth V8 was a block that was shared with any Hemi.
Yes.... you can install 241 Hemi cylinder heads on a 325 block.
Yes "drylakeswheel man" is correct
There are some valve size and port size differences however the heads interchange and work.
and i wont need any spacers(intake off the 241) being that the 325 is a raised deck block?
i have checked and the 325 is a hemi block and it looks brand new the pistons still have the factory etch in them
and ive heard ill need raised deck push rods?
You can, but why would you? The 241-270 have pretty small valves. The 315-325 poly head would likely make more power on a 315-325 than the 241 head.
Tall deck Dodge requires tall deck intake.
Side note: Dodge and DeSoto tall decks used different intake manifolds than the short deck engines. Chrysler engine intakes will fit both short and tall deck because the intake port location was moved in the 392 head to accomodate the 354 manifold. This is why an intake spacer is needed if you put 331-354 heads on a 392 block. If you put 392 heads on a 331-354 block then a one piece intake will not fit, you will need a 2-piece log type manifold.
i am asking because i have a basicly brand new 325 hemi short block and a 241 red ram with tri power so im trying to use the parts i have
The thought process is on target, but try to find better pieces to work with. There should be plenty of poly heads available at bargain prices.....everyone wants to convert to Hemi heads. If you have to have a Hemi (no problem with that) start looking for 56-57 heads and 56-57 intake. It will be a better package and you will be happier (by comparison).
Where are the valve notches in your pistons? Photo?
Read here and you'll find out why...
Here's a link to the first part, but you should read all of the series. Everything you ever wanted to know about building a Red Ram hemi:
John Beck who built the engine is not only a fantastic race engine builder, but also a hot rodder, Bonneville racer and all time good guy - he walks the walk.
Did I see the short block for sale? The 241 heads will fit the 315/325 but the oil sealing surface along the top of the head is marginal.
i dont know if you saw it for sale, can you explain to me what you are talking about? the oil sealing surface along the top of the head???
what is needed? can i use the intake off the 241 or do i need one off a 325 or can i use spacers? what about the push rods? can i use the 241's or do i need 325's?
You need a high deck 325/315 intake on a high deck block. No spacers needed. Did you follow the webrodder link to see how they put 241 heads on a 315? If you tried to use the 241 intake you'd need spacers, not sure if anyone has tried that.
On the Webrodder Form Doc was saying that there isn't much matching surface where the top of the head meets the top of the block(above the push rod holes) & it would be easy to get an oil leak there. 270 heads are a little meatier & 315/325 are designed to fit, obviously.
Seems like the 241 combustion chamber would be much smaller than the 325s chamber. Should be good foe a compresion increase. I wonder how much?
You can't use the 241 intake unless you make some spacers. No one sells them (it's a Dodge).
For push rods get the adjustable ones from Hot Heads.
Spacers are impossible because the angle on the surface. You would end up with a jog in the passage and the bolts would have to be jogged as well. You need the high deck manifold,and pushrods. The dowels will have to be changed as well. Don't expect it to run very strong without a lot of intake port work. The combustion chambers were all the same volume except for changes due to valves. When I tried some 241 heads on a 325 hemi block, I ran into problems and gave up.
The 241 heads are cast differently on the gasket mating surface in the pushrod area. I have heard of people using a bead of silicone along the top edge (pushrod hole area), or you could build up that area on the heads themselves with epoxy. BUT, as said, you would be way ahead of the game by finding the tall deck heads and intake.
No one makes an intake spacer because it would have to be well over an inch thick to get any type of port alignment at all.
The circled area is where the 241 head casting differs.
alright, ive spent countless hours looking for 325/315 heads and intake and have come up empty handed, anyone out there have 325/315 heads and intake that they might want to get rid of? also anyone interested in a 241 hemi with tri power??
check out this info that is on the webrodder forum link below as I asked the same question, there are some good photos & comments from well respected hemi gurus.....good luck.
between this link to the forum & the link on pg 1 to the article, I'd say this is covered!
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