PS. I read that HAMB article, interesting he had heads with different casting numbers again!
Maybe the 67 had issues with intake bolt angles like they do on an early 273??
318-3 Closed Chamber Truck Heads
- Thread starter 70coupe
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PS. I read that HAMB article, interesting he had heads with different casting numbers again!
Maybe the 67 had issues with intake bolt angles like they do on an early 273??
You talkin about weldin up the exhaust cross over? I wouldn't do it. It will be fine as a water passage. Long as the gasket seals good, run it.
67Dart273
Well-Known Member
This water crossover has intrigued me since I first learned of it years ago. Think about it. The coolant is MUCH cooler than the exhaust, it should somewhat alleviate fuel /vapor/ boiling problems I would think
pishta
I know I'm right....
My Mazdas intake is water heated too. Common outside V8's
67Dart273
Well-Known Member
And Ford V8's "back then" had a carb spacer with heater hose fittings.
I have those same heads on my daily driver dart, 318-3 from an RV. I had to change the oil pan, timing cover, and water pump and damper so it would fit in the dart. Indeed is a water passage under the carb. The carb stays cool and the engine runs great around town in the heat of the summer. Big spark plugs like a ford
Well runnin Ford plugs......that'll speed um up alright. LOL
Ohhh...those are nice....
BigBlockMopar
BigBlockMember
Nice find.
Is the exhaust seat face at 45° angle? It looks less than that.
A 3-angle valve job would help flow in that area.
Flowing air/exhaust doesn't "like" to take corners that are sharper than 15°. It causes turbulation that will slow down flow.
I would also smooth the transition into the port and get rid of any sharp edges. Also in the chamber itself.
Is the exhaust seat face at 45° angle? It looks less than that.
A 3-angle valve job would help flow in that area.
Flowing air/exhaust doesn't "like" to take corners that are sharper than 15°. It causes turbulation that will slow down flow.
I would also smooth the transition into the port and get rid of any sharp edges. Also in the chamber itself.
They are 45deg, the angle of the pic does make it look much less.
Thankyou for the advice, I was thinking a good valve job and deburr
stixx
Well-Known Member
Those ports scream for a sandpaper roll to blend the machining into the port...
Edit: BigBlockMopar already mentioned that. ;)
dutchie16
Member
Gday Pete,
by the looks of the photos & my memory, i think those heads were originally from the Dodge trucks 318's (approx '65-'73 D5N trucks) here in Aus & they used the water crossover design to stop the fuel vapourising, as these trucks were common throughout many country/rural areas, where the air temp can often be over 45^C (113^F).
by the looks of the photos & my memory, i think those heads were originally from the Dodge trucks 318's (approx '65-'73 D5N trucks) here in Aus & they used the water crossover design to stop the fuel vapourising, as these trucks were common throughout many country/rural areas, where the air temp can often be over 45^C (113^F).
On the end of both heads there should also be a small threaded hole. One will be plugged off and the other may have a temperature sending unit in it.
You could drill and tap for a pipe plug where the zip tie is, to shut off the water flow.
nm9stheham
Well-Known Member
Just for interest, I just computed the CR for closed chamber heads at 62 cc (which is a typical chamber size number for the 920 heads) and with a thin .028" head gasket (Mr Gasket 1121G), came up with around 8.5:1. So, better than stock with open chamber heads, but not particularly high.
Asking again....
Krooser
Building Chinese Free Engines since 1959...
Good score... I'd plug those water crossover hole unless I needed them for cold weather driving.
You Aussies get some interesting variations in those American V-8's...
You Aussies get some interesting variations in those American V-8's...
nm9stheham
Well-Known Member
They do a lot of creative performance development there. Some of the best parts I ever had for 1.6L and 2.6L Mitsubishi engines were developed and sold from 'down under'.... Weber intakes, pistons, trannie gear sets optimized for racing.....
pishta
I know I'm right....
Was that big 2.6 Bishi 4 banger a good motor? That's huge for a 4. Was that available in the Arrow?
nm9stheham
Well-Known Member
Yes, the Fire Arrow had a 2.6L NA motor. It was pretty potent in that very light car.
The best 2.6L's are from the later Mitsubishi Starions and Chrysler Conquests. When the turbo's were added in those cars, the factory added piston coolers (oil squirters under the pistons from the main gallery) and a better oil pump system. I think the rods and crank were better too. Stock pan on the turnbo ones even had some basic oil baffling. You can eliminate the balance shafts with a kit. Up the SCR to a true 8.2 with VW forged flattop pistons and the torque gets good off-idle and covers most of the turbo lag if you have the right turbo. I ended up at 1.75 HP per ci, totally reliable under racing conditions, with 14-15 psi boost limited with a wasategate in rally use.
Note that the earlier 2.6L's did not have as good of an oiling system or crank. So they are not as durable if you push on them hard as the later turbo'd versions.
The 1.6L's were good too. Nice little hemi heads that could be ported out to well over 200 cfm flow with bigger valves.
The best 2.6L's are from the later Mitsubishi Starions and Chrysler Conquests. When the turbo's were added in those cars, the factory added piston coolers (oil squirters under the pistons from the main gallery) and a better oil pump system. I think the rods and crank were better too. Stock pan on the turnbo ones even had some basic oil baffling. You can eliminate the balance shafts with a kit. Up the SCR to a true 8.2 with VW forged flattop pistons and the torque gets good off-idle and covers most of the turbo lag if you have the right turbo. I ended up at 1.75 HP per ci, totally reliable under racing conditions, with 14-15 psi boost limited with a wasategate in rally use.
Note that the earlier 2.6L's did not have as good of an oiling system or crank. So they are not as durable if you push on them hard as the later turbo'd versions.
The 1.6L's were good too. Nice little hemi heads that could be ported out to well over 200 cfm flow with bigger valves.
That's exactly what I was going to suggest but you beat me to it. I would not run hot water through the intake, unless you are in Alaska.
If you're referring to that 1/4 inch hole, plugging that hole wont do jack, the centre passage is wide open to the whole internals of the coolant of the head. (EDITED)
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67Dart273
Well-Known Member
Sorry incorrect. Of COURSE the coolant is in the head........he's speculating on whether it will "live" OK with the intake. Unlike blocking the exhaust crossover, "if it seeps" a little it will NOT be OK in this case
I don't see it being any different to the water jacket that goes into front of the manifold, and I have never seen or heard of a failure in this area.
My questions are not about performance, but since you ask, I do not have a magic number in mind. It's a good running stock engine I am freshening up while I repaint the car. The car is a weekend driver, not a race car.
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