Is there a junkyard gem slant six combo?

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A38Valiant

A38Valiant

Collector Of Rust
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I'm looking to build a slant six for one of my future projects. In my current inventory, I have 225s from the following years...
1967
1972
1975
1976
1979 Super Six
1980 Jasper reman
1983

So, my question is basically, is there any year that is better than others as far as block, crank, pistons, rods, head, etc etc etc. I plan to basically just give the parts a good cleaning, run a hone through the block, and do a simple "bearings rings and gaskets" overhaul, but perhaps have a cam reground. Engine will be in a 75 Swinger with a 3 speed manual trans, and will feature a home built intake manifold of my own design with 3 Holley 1920s. Thanks in advance
 
i don't know the magic recipe of which head is the best, which bottom end has the most compression and/or best pistons and rods, but that seems to be the direction you're heading which is excellent.

i will however strongly encourage you to run something other than the 1920's, anything other than them suckers. or at least build your manifold so that it can accept another carb when you tire of fussin' and fightin' with them god forsaken things.
 
junkyardhero said:
i don't know the magic recipe of which head is the best, which bottom end has the most compression and/or best pistons and rods, but that seems to be the direction you're heading which is excellent.

i will however strongly encourage you to run something other than the 1920's, anything other than them suckers. or at least build your manifold so that it can accept another carb when you tire of fussin' and fightin' with them god forsaken things.
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I'm probably using the 67 pistons, just assuming more compression. But I'm looking for insight on block, head, crank, rods, etc....

What's wrong with the 1920 carb? It's been several years since I ran one, but I always thought they were about the best 1 barrel ever put on a slant. Only one that ever gave me trouble was on a 72 Dart I had, 69K one owner miles. Going to work one day, it decided it wouldn't run less than half throttle. After a rather "interesting" ride the rest of the way to work, I tore into it on my lunch break. Dirt in the bowl, holding the needle open. And then looked at the fuel filter, or more precisely, the lack of one. Factory one use clamps on all the connections. Apparently, it slipped by the guy installing filters on the assembly line. And it took it 69K miles and 28 years to decide to be a problem, lol.
 
All factory slant six pistons will be the same CR. There are some different aftermarket piston configurations within the "stock" description. Some have a slightly lower compression distance. There are also aftermarket "export" low compression pistons. Be careful you don't get these. For what you are wanting to do, Any 225 block, pistons, and rods would be essentially the same. The main thing you need to be aware of is the change from the small to large crank rear flange between 1967-1968. Also the change from forged to cast crank in 1976 (the crank and block changed). 1980 and 1981 engines you have were hydraulic lifter engines. Solid lifter engines and hydraulic lifter engines can be converted in either direction by swapping the complete valve train (cam, lifters, pushrods, rocker arms, rocker shafts). Be aware that the factory used a steel shim head gasket, and the aftermarket only has a thicker gasket available, so you would lose compression if not milling the head or cutting the deck to compensate. If cutting the deck or milling the head, I recommend cutting more than the minimum required to increase the CR higher than stock. Up to a certain point there is no downside to raising the CR. It will help both power and fuel milage.
 
IMO, the 79 Super Six is the best to build. Cast crank engine, but still solid lifters. The cast crank will take whatever you can throw at it and is much lighter than the forged crank. That'd be my choice. In fact, I'm lookin for one. lol
 
I would say any older one that has a solid lift cam . But get a head without the spark plug cups they had hardened seats . Also have the head done at a machine shop. The head and valve adjustment are the most critical for performance. Raise the compression with cutting the head.

I had a 62 's with a 225's and a push button trans. I would coast the car backward as fast as I could down a steep hill . Hold the throttle flat out and push the low button. As soon as the "tire" was smoking I'd push the second gear button still going backwards. Then I'd here the tire start to sizzle I'd hit drive then back to second when it would start going forward.

We would make the biggest J you would ever see. We had dodges and plymouths. We were not going fast but had a hell of a lot of fun. Those Slant sixes took a beating. Just keep the oil clean they get black quick .
 
"Engine Power" the TV show did a rebuild on a 225 in season 10, episodes 9 and 10. Lot's of goodies and upgrades. Might be worth checking out.
 
Charrlie_S said:
. For what you are wanting to do, Any 225 block, pistons, and rods would be essentially the same. Also the change from forged to cast crank in 1976 (the crank and block changed). 1980 and 1981 engines you have were hydraulic lifter engines.
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Cast crank engines have narrower rod journals don't they? I was wanting to pull the rods out of my '72 198 to use that engine for the lighter crank, and if I remember right lighter block.

I am eyeing my neighbor's '80 or '81 van. A friend used to own that van and I knew that van when it was bought used with 3-9000 original miles on it. It definately had solid lifters when I pulled the head off. I replaced it with ahead from his old '77 that I had a local machine shop do the valves and slice .060 off the bottom. I did what I call an "RV Port, and Polish" on it. Dropped the 77 Super 6 intake on it with a BBD that I rebuilt. It worked good with the 833OD and 3:55 rear.

Did any of the slant heads have hardened seats? I thought they were flame induction hardened.
 
'75(?) up use the 5/8" "peanut" plugs without drool tubes, I'd use that head to reduce potential oil leak points. to use the 198 rods, you'll probably need a forged crank bottom end. also to use those rods, you need pistons with a compression height in the 1.6" range. 2.2L chrysler pistons fit the bill and have the same size pins, but you'll need to bore it out, since the stock bore size on the 2.2L is 87.5mm (3.445").
 
I thought so, but don't quote me on it.....this pic looks like both the mains and rods are narrower on the cast....Is this a cast or forged crank?

looking on rockauto, conrod bearings for a cast crank look to be .72" wide, for a forged crank .988" wide
 
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michiganpat said:
I thought so, but don't quote me on it.....this pic looks like both the mains and rods are narrower on the cast....Is this a cast or forged crank?

looking on rockauto, conrod bearings for a cast crank look to be .72" wide, for a forged crank .988" wide
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I want to go EFI/turbo eventually. Lighter reciprocating assembly, possibly a lighter block too. The cast crank should handle a turbo. Narrow the rod ends so I don't have to buy K1 rods.
 
michiganpat said:
'75(?) up use the 5/8" "peanut" plugs without drool tubes, I'd use that head to reduce potential oil leak points. to use the 198 rods, you'll probably need a forged crank bottom end. also to use those rods, you need pistons with a compression height in the 1.6" range. 2.2L chrysler pistons fit the bill and have the same size pins, but you'll need to bore it out, since the stock bore size on the 2.2L is 87.5mm (3.445").
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Cast crank slant six uses a different block, rods and crank than the forged crank slants. The rod and main journal are narrower. If using the 2.2 pistons make sure they are compatible with whatever rod you use. Not only on the pin location/rod length, but on whether the pistons are for floating pins or press fit pins. I wanted to run 2.2 non turbo flat top pistons, with K-1 rods. No can do. the rods are made for floating pins, and the piston are for press fit (no lock grooves). The 2.2 turbo pistons are for floating pins.
 
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