Buick 225 and 231 V6 parts interchangeability. Frankenstein V6 build.

AyWoSch Motors

AyWoSch Motors

Gear Grinder
Mar 15, 2023
7
Las Vegas, New Mexico
First Name
Ayden
Willys Model
  1. Pickup
  2. CJ
Willys Year:
  1. 1948
  2. 1952
So i recently i bought a package deal of a 52 willys wagon, a mystery CJ5 chassis, 4 buick 231ci V6s, a dauntless 225, 2 superhurricane 226, and a F134 Hurricane, 5 transmissions, 3 transfer cases, set of axles, rims, and a ton of parts. Traded my 75 C30 chevy for it.

Anyway....
Out of those 5 V6s, i picked the best one as my base for a rebuild. The one i picked is a 1979 -231 block out of a Regal.
Block is healthy. I deep cleaned it, honed the cylinders and lifter bores, polished the bearing journals, and painted the block. Its ready to assemble. No out of all the extra parts i have, ive picked the best of each. Now im down to picking a crank and cam.
I have one good oddfire crank, and one good even fire crank, and about 3 good cams, but i don't know which one goes to which engine.

My biggest issue that determines what parts i use is which cam is for even fire and which cam is for oddfire.
That will determine what crank i use, and what bearing kit i have to by.
Is there any way to tell them apart, by style or part number?

No i know the 225 have a different size journal bore, so inlimintates that one. So really i just need to know if the remaining cams i have are 75 to 77 oddfire 231, or the 77 to 87 even fire 231.
Someone told me that the cam with the removable fuel pump lobe and distributor gear are the older 75 to 77 ones, but i cant seem to corroborate that anywhere.

I dont really care which crank/cam i use. Im more used to the evenfire, but a friend told me, for just putting around the ranch low RPM that the oddfire might be better.

Also, it being a 79, it would have been an even fire engine. Will a oddfire fit and work with no issue if i go that way?

Anyone have any insight on which might be better?
Anyone have anyway to tell cams apart? Parts numbers i can check?

Thank you..
 
If nothing else, put a degree wheel on the nose and look at the angle between intake valves. There should be an obvious difference between even and odd. Even if you just roll the cam on a table with the degree wheel off the edge you should be able to get numbers within 5 degrees and tell them apart.
 
AFAIK, or can remember, even fire and odd fire are different animals. I think nothing is interchangeable. Maybe the oil pan. Maybe.

There is a really good book by a guy named Pat Ganahl that goes into detail about the Buick V6 engines. The same volume has chapters on the early-mid Chevy V6 and the Ford (?) V6. The book is from the 80s I think so you'll find no info on later V6 engines. If you can find a copy, grab it if you are seriously interested in these engines.
 
wheelie said:
AFAIK, or can remember, even fire and odd fire are different animals. I think nothing is interchangeable. Maybe the oil pan. Maybe.

There is a really good book by a guy named Pat Ganahl that goes into detail about the Buick V6 engines. The same volume has chapters on the early-mid Chevy V6 and the Ford (?) V6. The book is from the 80s I think so you'll find no info on later V6 engines. If you can find a copy, grab it if you are seriously interested in these engines.
Click to expand...
I will look for that..

What i found funny, is that all those blocks were mix matched. The 1967 225 and the 1977 231 both had evenfire cranks, and the 2 1979 blocks and the 1987 block had oddfire cranks in them. They all looked like they ran at some point like that.
Seemed completely backwards from what i could tell, so i guess they are interchangable to some point.
 
when it comes to details regarding 225/231 OF vs 231 EF - best source of knowledge is the ecj5.com site.....afaik, the blocks are interchangeable, but all the internals must either be EF or OF - there is no mixing and matching of internals parts. As for which cam is EF vs OF - ask at ecj5. The cranks will differ based on split vs single journal....as mentioned above, looking at cam lobes with a degree would probably tell, but, I can think of Donny, Rich, Nick, Oldtime etc would all be very knowledgeable about that on ecj5.....
 
FinoCJ said:
when it comes to details regarding 225/231 OF vs 231 EF - best source of knowledge is the ecj5.com site.....afaik, the blocks are interchangeable, but all the internals must either be EF or OF - there is no mixing and matching of internals parts. As for which cam is EF vs OF - ask at ecj5. The cranks will differ based on split vs single journal....as mentioned above, looking at cam lobes with a degree would probably tell, but, I can think of Donny, Rich, Nick, Oldtime etc would all be very knowledgeable about that on ecj5.....
Click to expand...
X2
 
AyWoSch Motors said:
So i recently i bought a package deal of a 52 willys wagon, a mystery CJ5 chassis, 4 buick 231ci V6s, a dauntless 225, 2 superhurricane 226, and a F134 Hurricane, 5 transmissions, 3 transfer cases, set of axles, rims, and a ton of parts. Traded my 75 C30 chevy for it.

Anyway....
Out of those 5 V6s, i picked the best one as my base for a rebuild. The one i picked is a 1979 -231 block out of a Regal.
Block is healthy. I deep cleaned it, honed the cylinders and lifter bores, polished the bearing journals, and painted the block. Its ready to assemble. No out of all the extra parts i have, ive picked the best of each. Now im down to picking a crank and cam.
I have one good oddfire crank, and one good even fire crank, and about 3 good cams, but i don't know which one goes to which engine.

My biggest issue that determines what parts i use is which cam is for even fire and which cam is for oddfire.
That will determine what crank i use, and what bearing kit i have to by.
Is there any way to tell them apart, by style or part number?

No i know the 225 have a different size journal bore, so inlimintates that one. So really i just need to know if the remaining cams i have are 75 to 77 oddfire 231, or the 77 to 87 even fire 231.
Someone told me that the cam with the removable fuel pump lobe and distributor gear are the older 75 to 77 ones, but i cant seem to corroborate that anywhere.

I dont really care which crank/cam i use. Im more used to the evenfire, but a friend told me, for just putting around the ranch low RPM that the oddfire might be better.

Also, it being a 79, it would have been an even fire engine. Will a oddfire fit and work with no issue if i go that way?

Anyone have any insight on which might be better?
Anyone have anyway to tell cams apart? Parts numbers i can check?

Thank you..
Click to expand...

As I recall several years ago I assembled my 225 Odd Fire using 231 rods and heads. I used the rods because there was a matched set and balanced better than the ones previously installed. I had to hone the pin bushing slightly to fit the Odd Fire pins and pistons. The 231 heads have larger valves, but I retained the Odd Fire rockers because the lift ratio was better. The only drawback was finding a set of pushrods. a company out west helped me out there. It ran so well that after a little use I treated it to an aluminum 4barrel intake and a baby Holley carb (390cfm). With a slight mod on the carb to help proper bowl venting, it has proved reliable and power the old M38A1 any where I dare. ps Good luck to the next fellow trying to figure out what I did!
 
Be very carefull, nothing will switch from odd to even fire, most will not even fit, and the cams are miles apart, and the 225 stuff is odd as well...when you are done you will be a export on the v6,s...Phil
 
@Jeepsterjim knows the differences between the even fire and odd fire.
Him an I tore down an even fire shortblock one afternoon, and he was showing me the differences between the heads and blocks.
Pistons interchange with the Buick 350 V-8, and we were comparing part numbers.
Jim will soon be building a V-6, and can't remember which way he will go. _ _ _ _ odd or even.
 
So I got on Ecj5, and couple guys there helped clear up some things. Turns out i was being stupid, and got some things messed up.
See I've never messed with a V6 before, this is new territory. Ive rebuilt big block and small block V8s, straight 6, and 4 cylinder engines before, which are all naturally balanced engines and v8s share a commom rod pin. Im very used to seeing v8 crankshafts.
I saw the odd offset looking crank, and assumed that meant oddfire, and saw my of so familiar shared pin crank, and assumed that was even.
I learned something new. I was being stupid. Explains why all my research seemed very confusing, and it explains why all the engines are set up the way they are.
That actually answers all my questions, and makes for an easy decision.

Everything is as it should be.
Im going to take all the internals out of my turbo 86 block, and put them in my 79 block. Same generation, both even fire, should be fine. Now i know what can i can use, and eat bearing kit i need to buy for.

Got this issue all figured out for now, im happy.
 
A lot of the stuff will fit between the two, but not neccessarily will work together, so you need to be thoughtful. I have a FrankenV6 that's a mixture of 225, 231, and 252 but it's been so long that I don't remember what combination. I've switched the HEI from odd fire to even fire by swapping out the pole piece and cap when swapping stuff around. I once drowned an engine and wiped out the bottem end and needed it running the next weekend so I literally swapped out the even fire bottom end for an odd fire (or vice versa?) and after re-doing the distributor I think I just transfered the heads, intake and exhaust over. I had some valve train things to adjust, but I think that's what's in it now. So yeah, a lot of mixing and matching can be done but the cam, block, and crank are what they were born as and stay either even or odd. The other stuff can be transfered with some research.
 
AyWoSch Motors said:
A few pics of my build so far, just for fun...View attachment 137606View attachment 137607View attachment 137608
AyWoSch Motors said:
So i recently i bought a package deal of a 52 willys wagon, a mystery CJ5 chassis, 4 buick 231ci V6s, a dauntless 225, 2 superhurricane 226, and a F134 Hurricane, 5 transmissions, 3 transfer cases, set of axles, rims, and a ton of parts. Traded my 75 C30 chevy for it.

Anyway....
Out of those 5 V6s, i picked the best one as my base for a rebuild. The one i picked is a 1979 -231 block out of a Regal.
Block is healthy. I deep cleaned it, honed the cylinders and lifter bores, polished the bearing journals, and painted the block. Its ready to assemble. No out of all the extra parts i have, ive picked the best of each. Now im down to picking a crank and cam.
I have one good oddfire crank, and one good even fire crank, and about 3 good cams, but i don't know which one goes to which engine.

My biggest issue that determines what parts i use is which cam is for even fire and which cam is for oddfire.
That will determine what crank i use, and what bearing kit i have to by.
Is there any way to tell them apart, by style or part number?

No i know the 225 have a different size journal bore, so inlimintates that one. So really i just need to know if the remaining cams i have are 75 to 77 oddfire 231, or the 77 to 87 even fire 231.
Someone told me that the cam with the removable fuel pump lobe and distributor gear are the older 75 to 77 ones, but i cant seem to corroborate that anywhere.

I dont really care which crank/cam i use. Im more used to the evenfire, but a friend told me, for just putting around the ranch low RPM that the oddfire might be better.

Also, it being a 79, it would have been an even fire engine. Will a oddfire fit and work with no issue if i go that way?

Anyone have any insight on which might be better?
Anyone have anyway to tell cams apart? Parts numbers i can che
Click to expand...
Click to expand...
 
Have fun. If I remember correct, the odd fire cams did have removable distributor gears and fuel pump concentric. Also the odd fire oiled the rockers through an oil gally in the block and heads, where the later 231's oiled through hollow push rods. So lifters push rods, heads and rocker arms are not interchangeable.
 
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