Open Topic Engine Thread?

[cavisco1]

Does anyone have any information on stock cam specifications and what years had the best cam? Might be interesting to see what the factory cams were as a baseline. I've been re-reading some camshaft discussions over at slantsix.org and some are proponents of a reverse dual profile where there is a longer intake duration and short exhaust duration. The thinking behind this is the long stroke small bore of the slant is more severely intake limited than exhaust limited. The longer duration on the intake helps the intake side while the short exhaust duration helps keep the overlap reasonable. Apparently this gives a boost in the low to midrange rpm band where these torquey long stroke motors excel. Apparently the Chrysler engineers did this exact thing with a couple of the later stock grinds for the slant. I know this sounds counter intuitive as most V8 dual pattern grinds feature longer exhaust durations, but I think these long stroke inliners require some different thinking than just copying what the V8 boys are doing. The flattys are even more intake challenged with the siamesed ports and side-valve arrangement. I'm thinking the flat-heads would respond well to this type cam and would enhance the long stroke low rpm torque inherent in their design while keeping them well mannered with a smooth idle. Anyone else have any thoughts on this?

[timkingsbury]

There are a huge variety of cam specifications and "what years had the best cam" is a question of what you are trying to achieve.  In the generations of the Canadian big bock (25 1/2") engine there are around 80 different cam specs.

 

While I have heard a lot of people call the slant six as a long stroke motor;  here is the slant 6 specs:

 

For the 170 slant-6 the engine has a bore of 3.40 in and a stroke of 3.125 in   for an actual displacement of 170.2 cu in (2.8 L). Connecting rod length is 5.669 .The 225 used the RG (tall) block with a 3.40 in  bore, a 4.125 in  stroke, and 6.699 in connecting rods, for an actual displacement of 224.7 cu in

 

The flathead 6 cylinder of lets talked the later generation flathead produced in Canada often referred to as the 238, 250 and 265 ci motors were  all 3.4375 in bore and strokes of  4.125 in,  4.50in and 4.75 in so in reality the flathead had bigger bore, and bigger stroke.

 

Yes Chrysler made a hyper-pack  with a 10.5 /1  compression engine and a  276°-duration camshaft. with a four barrel carb on it.  But the head, and therefore intakes and exhausts are dramatically different.

 

Back to the flathead 6 cylinder and lets just take the 265 ci flathead 6 motor.  In 1952 they had a cam grind for the Chrysler, and 2 different ones for the truck. that engine in 1954 had 2 cam grinds for trucks,  3 for boat engines (marine) 1 for the Chrysler, 1 for the Desoto, and several for industrial application as they were using it from welders, waterpumps, combines,  swathers etc..  So there was higher rev for boats... more torque and horsepower for the truck, one of which

had factory dual carbs and dual exhaust, and some of the 265 for industrial applications had very torque enhanced cams.

 

Now factor that Mopar, made about 30 different flathead 6 cylinders, from the 23 1/2" USA small block to the 25 1/2" Canadian big block, and then an even bigger truck block.

 

But it goes back to my earlier question, being what exactly are you trying to achieve ?  Finally, the flathead actually has much more exhaust challenges than intake challenges believe it or not. I can definitely explain how to get more fuel available for the engine than I can get it to burn.

 

Sorry -  I realize this likely more confuses than helps. 

 

Tim

[Mopar Mick]

Go to "you tube" and type in Turbo flathead six.

It's a very interesting video.

It has just a small hint of a turbo whistle.

Sounds very good.

Mick.

Edited February 10, 2015 by Mopar Mick

[timkingsbury]

I believe these are the ones Mick is referring to.. 1st to last posted generation of the project

 

https://www.youtube.com/watch?v=dskutHwOy7U

https://www.youtube.com/watch?v=qBbi56Nefzk

[Robert Horne]

Here is a photo listed as a Chrysler 6, T120.

 

The unusual exhaust would appear to be a good fit for a turbo charger..

[timkingsbury]

Here is a photo listed as a Chrysler 6, T120.

 

The unusual exhaust would appear to be a good fit for a turbo charger..

Yes.. they had the exhaust going up for a lot of things, such as tow motors, swathers, and combines. I have seen them on small and large blocks. As well on the massey harris tractors, some welders, generators  there were updraft carbs and exhaust going up like you  have shown. So there are quite a few intake and exhaust combo's to pick from.

 

I have 2 massey tractors with Mopar engines from the factory. One is a 23 1/2" US bock row crop and the other is a 25 1/2" Canadian big block in a Massey Harris 101 super with a rare standard front end.   I am also in the process of building a Generator powered by a Canadian big block (250 ci) big block and it will run the exhaust up setup, with a governor.   The gap in that project at the moment is finding the Rockford or similar clutch which I think I see on your picture.. I want to be able to start the engine, warm it up and then engage the generator which up until now ran via a pto shaft to a tractor.  I mention that, because interestingly the exhaust while it exits up is at the back of the exhaust while the one you show and the Massey tractor come off the front.   I can take pictures of the various combos if you or anyone are interested in seeing them and if you want to get silly, it wouldn't be to tough to hook a turbo off the front and back, lol at least from the logistic standpoint of mounting the turbos to the exhaust side.

Edited February 12, 2015 by timkingsbury

[Robert Horne]

Here is another photo with the exhaust coming out the front/side with an updraft carb.

 

Timkingsbury, would be interesting to see any different exhaust setups.

 

I will have to watch for any old Masseys around here.  

 

I have a turbo sitting on the shelf, wanting to put on my 56 engine..   

 

 

[Young Ed]

Bob look closely at that. It appears to be the normal intake and exhaust set flipped upsidedown.

[Frank Elder]

Bob look closely at that. It appears to be the normal intake and exhaust set flipped upsidedown.

Looks like an ind to me or a combine intake.

[Dave72dt]

Bob look closely at that. It appears to be the normal intake and exhaust set flipped upsidedown.

All the mounting bolts appear to be in the stock location.  Flipping it would require new locations for mounting bolts.  Agree looks more like industrial or ag use

[Robert Horne]

Bob look closely at that. It appears to be the normal intake and exhaust set flipped upsidedown.

 

There is a listing on ebay of a "water transfer pump" that has the Chrysler engine with the exhaust very similar to this one,

as far as I can tell......

[timkingsbury]

Here is another photo with the exhaust coming out the front/side with an updraft carb.

 

Timkingsbury, would be interesting to see any different exhaust setups.

 

I will have to watch for any old Masseys around here.  

 

I have a turbo sitting on the shelf, wanting to put on my 56 engine..   

Ok.. I will put it on my to do list.. Your picture is indeed an updraft with the front top exist I referred to.  I do think there is a lot of work to be done

after mounting the turbo on to the exhaust side so it will spin it. lots..

[48Dodger]

My little forklift has a flat 4 with the "flipped" intake/exhaust/carb deal.  

Keeps things compact and under the seat, so to speak.

 

48D

[Tim Keith]

I read a thread on the HAMB advocating domed pistons for a flathead Ford.   A 1/4-inch to 7/16-inch dome was said to increase compression without restricting flow.  I don't know whether this claim is anecdotal and can't be proven, or whether this actually improves turbulence in a flathead.   The goal was to not mill the cylinder head to increase compression but to use a moderate height piston dome to raise compression. 

[55 Fargo]

...

Edited May 12, 2017 by 55 Fargo Spitfire

[austinsailor]

We have a local machinist who has done many odd things over the years. When go carts were the fad, he used outboard motors, as an example. Lots of his special tricks done to them, he blew the socks off of everyone else till they banned him. Only way anyone else could win. He also took flathead mopars and welded up the piston tops to increase the compression. Home made dome pistons, I guess you could say.  I guess it worked, people who were around when he was doing it said they ran pretty good.

 

I see him occasionally, I'll quiz him about it.

[T120]

I read a thread on the HAMB advocating domed pistons for a flathead Ford.   A 1/4-inch to 7/16-inch dome was said to increase compression without restricting flow.  I don't know whether this claim is anecdotal and can't be proven, or whether this actually improves turbulence in a flathead.   The goal was to not mill the cylinder head to increase compression but to use a moderate height piston dome to raise compression. 

Yes,And I suppose with our past experience,calculations and modifications we would have to use one of these to ensure we were on the right track.    

 

[Tim Keith]

We have a local machinist who has done many odd things over the years. When go carts were the fad, he used outboard motors, as an example. Lots of his special tricks done to them, he blew the socks off of everyone else till they banned him. Only way anyone else could win. He also took flathead mopars and welded up the piston tops to increase the compression. Home made dome pistons, I guess you could say.  I guess it worked, people who were around when he was doing it said they ran pretty good.

 

I see him occasionally, I'll quiz him about it.

 

The theory is since milled heads tend to decrease the air flow, that domed pistons basically drop away so that the air flow remains good without milling the head.   Increased  "quench" or turbulence is the goal.    1/4-inch dome does not sound like much, but maybe it would help some.  I think domed pistons can have hot spots that also might not be ideal.  Probably just about every trick has been tried by someone.

[timkingsbury]

The theory is since milled heads tend to decrease the air flow, that domed pistons basically drop away so that the air flow remains good without milling the head.   Increased  "quench" or turbulence is the goal.    1/4-inch dome does not sound like much, but maybe it would help some.  I think domed pistons can have hot spots that also might not be ideal.  Probably just about every trick has been tried by someone.

well for the flathead ford your dealing with a much different head chamber that a flathead mopar.  In fact some of the aftermarket flathead ford heads changed the head chambers.   So yes you can use a piston which elevates above the block deck.  The traditional "dome" pistons don't work, as you need more of a side dome, which yes I know you can have made.  Ive seen many use chevy pistons and put part of the piston that would hit the head and that can be successful.  You will also find in both the usa small block and the Canadian big block that there are different heads right from the factory which had higher compression to them.  That is also a great and inexpensive method, verses the new piston route.  Still tough to beat the significant gain in compression

by shaving the head which is fairly inexpensive way to gain power.

 

Tim

[Tim Keith]

well for the flathead ford your dealing with a much different head chamber that a flathead mopar.  In fact some of the aftermarket flathead ford heads changed the head chambers.   So yes you can use a piston which elevates above the block deck.  The traditional "dome" pistons don't work, as you need more of a side dome, which yes I know you can have made.  Ive seen many use chevy pistons and put part of the piston that would hit the head and that can be successful.  You will also find in both the usa small block and the Canadian big block that there are different heads right from the factory which had higher compression to them.  That is also a great and inexpensive method, verses the new piston route.  Still tough to beat the significant gain in compression

by shaving the head which is fairly inexpensive way to gain power.

 

Tim

George Asche told me I might measure the chamber volume of my 237 Desoto and see if it would raise the compression when used on a 265.   He didn't know for sure if that would be the way to go.

[cavisco1]

If any of you are interested in ignition upgrades, there is an interesting article on this site (  http://www.worldphaco.net/ ) comparing points/Kettering system, HEI and Capacitive discharge systems. Click on the pink link Capacitive Discharge Ignition (CDI) vs Magnetic Discharge Ignition (MDI).

 

Scott.

Edited February 15, 2015 by cavisco1

[55 Fargo]

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Edited May 12, 2017 by 55 Fargo Spitfire

[Frank Elder]

We whipped them....we had more horses and good looks on our side!

[55 Fargo]

...

Edited May 12, 2017 by 55 Fargo Spitfire

[Frank Elder]

I hate to say it but the 8 had the most appeal......