cam install question

[Matthew Ziegler]

A diesel mechanic buddy of my dad's is installing a new higher performance cam in my m37, he asked me how far the hub which bolts to the timing gear is pressed on? there's an exhaust flange shaped steel retainer behind it which holds the cam in, anyone know the correct space between the two? thanks in advance, Matt.

[Gordon Maney]

I don't have the parts here in front of me, but I would think it was not possible to press it on too far.

[Matthew Ziegler]

too far

The way it was described to me the hub can be pressed on pretty far, perhaps to the point of hitting the retainer plate. I'm just repeating the guy who's installing it's question, not sure if it'll mess up the alignment between the two timing chain sprockets or cause some other related problems.

[Cheyenne Dave]

The hub is pressed on flush with the end of the cam...dats all dere is and dere aint no mo.

CD

[Matthew Ziegler]

thanks

Thanks Dave, can't wait to get a little more power out of this truck, lots of hills around here. I tend to start a lot of parades, me up front and anxious yuppies following.

[Kaiser2boy]

Question, is the rest of the engine original? how much do you figure to gain? Are you still running the original carb with a governor?

I too live in hill country and have learned that the ol 37 really likes down hills but not so much the up hills. I get down to 25 MPH on long hills. If its a steep hill its way worse.

[Matthew Ziegler]

power

I can't be a hundred percent sure, the cam I got is supposedly worth about 15hp, Charles from M Series recommended shaving the head .080 to increase compression, Langdon's stovebolt engine company sells headers, I'm not sure how much they'd help but can't hurt. supposedly it's possible to add around 40 hp to these things provided the motor you start with is in good shape. Google Edgy speed shop, Langdon's stovebolt engine company and Kansas kustoms, the last will rework a stock exhaust manifold to look like a factory dual, very nice stock appearing job too.

[Kaiser2boy]

30 or 40 HP gain would be nice if it does not require higher RPMs. That long piston travel will not like over reving.
Keep us posted on how it works out and if you get any seat of the pants power gain and not just a theroretical gain.
I have done stuff to the old Harley I had and it boasted "big power gain" and in the end the gain could only be seen on a dyno test. The only thing I did on the Harley that made a big gain was refitting a big honking carb to it. That made a big improvment. I stuck a 45 MM carb on it and away I went.

[Matthew Ziegler]

I'll let you know.

you reminded me, the cam is also supposed to give me another 500 rpm, not sure how, I'm going to ask a friend of mine, who's a mechanic, I'm just a halfass machinist.

[Kaiser2boy]

Hmm.
Maybe it needs the extra 500 to get to the claimed power.
That engine tops out at about 3200 RPM if you are running the original carb and it is set up right. The engine has a long stroke and really does not like high RPMs.
If you need to push it to 3700 to get the extra power you may end up with a few dents in the hood from pistons leaving the engine. Ask some questions about the 500 extra rpms.
It has been my experiance that all engines have a flaw some place and the higher you rev them the faster you find the flaw.
The ideal thing would be a 10 to 15 HP gain without trying to rev the snot out of the engine.

[Matthew Ziegler]

rpm

allright, as i understand it, holding the valves open longer with more overlap seems to act like a split second compression release, compression for less? time, this gives you a few more rpm. I think I got it right. keeping the stock carb and intake on it for now, I'll keep my right foot in check and The stock governer can't hurt. while the Intake and exhaust manifolds were off, I examined them, some of the passages where the manifolds bolt to the motor needed porting badly, like 1/8 inch lip around the inside of the flange, I could see where the gaskets were and used a 1 inch 80 grit drum sander in a die grinder to open up the flanges and smooth the runners. This only took a few hours, and was basically free, I doubt I'll get a lot of power. However, why install a cam to make the motor breathe better and leave the manifolds in their overly restrictive stock condition. I should have the truck back on the road later this week, I'll let you know how it works. Matt

[Kaiser2boy]

Ha Ha Ha, A polished and ported Dodge 230 cu in 6 with a cam wow you should be able to turn the 1/4 mile in under 30 seconds. All kidding aside , every little bit helps plus its fun.
We will stay tuned for your test results. Good luck.

[Matthew Ziegler]

fast

I might finally be able to leave my buddy Dave's model a in the dust! the Farmer next door wants me to go against his international cub for pink slips...hmm olive drab farm tractor would be cool.

[Kaiser2boy]

If you go bumper to bumper in a push,,you will win. I have said for a long time the M37 is probably better suited for agriculture work. There is a photo of my 37 on the " MY M37 REBUILD POST,IT IS ON PAGE 11 PICTURE 162.
Alan in North Central Pa.

[Matthew Ziegler]

nice truck

Looks like the one in the manual ,very nice. I had a little fun with mine, desert tan, black top, black fenders grille and running boards, I used semi gloss paint, super swampers, (mistake). it still looks military, just a little different. got tired of having mine look like ten others at shows.