4W1765 CAT CAMSHAFT, THE GOOD THE BAD & THE UGLY

The early cams were hard on rocker shafts, clips, and bridge pins. We done more spun lifters and had to sleeve those lifter bores on those engines than any of them when I was at CAT. I wouldn’t tear into one just to change it but if I was in it for other things and it was handy yes I’d definitely change it.

 

So you can what bend a push tube? Yes you can but end of time you are just moving the weak link on a push tube engine. You asked for my opinion and I’ll tell you. The 100-7048 is as good a cam as that old high ramp troublesome #######. The 1465 has no better lift than the 7W-3796 or the 100-7048. It only has a really high lift all at once or less duration. With more lift you want more duration to keep the valves open longer. Lift does 0 good with out duration. The 7W-3796 is the factory 460 peec cam and if you order it it’s replaced with the 100-7048. There is a reason CAT added duration to the cams.

There is an honest to God reason I’m steering you away from the 1465 and I swear on my reputation as well as the man’s reputation that taught me every single thing I know it’s not to sabotage your build.

Find the centerline on the 1465 and measure its lift. Then find it on the other two and measure their lift. Your gonna find its an optical illusion. Nothing more.

 

I also want to say this bigger cubes make power low. Just plain and simple all there is to it. RPM is not gonna be 17L friends. More lift is going to move your power band up higher in RPM. Your building this motor to work not for a sled track or 1/4 mile loaded trac. Those JWAC engines were designed for an RPM band higher than you’re gonna want. Also a higher lift cam is only as good as the head it’s sitting on. It’s also only as good as its fuel supply. We all know without a Sigma pump or a Cyclone pump there is your weak spot. Unless you have the money to get 3 or 4 sets of plungers and barrels built. Then we can source a bigger unit there. End of time more displacement is gonna have way more torque without altering the fuel. If you make 500hp the torque will be up and you’ll never guess it’s 500. Then the trouble your gonna fight is when that rod comes around the bottom of the stroke there’s so much dwell angle it’s gonna rock that slug in the bottom of the liner and cause more issues. I’ll be honest the absolute best bang for the buck is go with a 15.2L set up. You’ll make as much power with more longevity.

 

Duration is measured in degrees of crank rotation not cam rotation.
Placing them in a stand with a degree wheel on them tells you 0.

Duration is measured at .050 lift not off the base circle.


Shorter duration equals better low end


Longer duration adds power higher in the RPM band.


Again that pic with 310 on the gear means absolutely nothing. Why because the same cam is used in the 460.
Call your local CAT dealer have them give you the part number on the cam and HP on 5YG00466

Specs are it’s a 460HP PEEC.
cam 7W-3796.

 

The nozzle for that serial above is gonna be 3425 as well. Early diesel garage post say it’s 350 stuff.


And that nozzle was used in some 350 4CK motors. However all the 5YG’s were 460’s. All had 14 degrees base timing and all would walk a mud hole in the 4CK 460 PEEC.

 

I was making the point that many parts are the same across different HP ranges. There are hundreds of combinations it boils down to arrangement number. I also use reman numbers on all my nozzle descriptions for simplicity. As in 8789 is the reman number for the nozzle you use. It comes from a 4ZR genset motor. Has a 140 degree spray cone. Designed to run at 18.5 degrees timing at idle and at 28.0 degrees timing at 1800RPM. With a 125-8869 piston crown. 1 big ### turbo and 6.07mm full load static fuel and 6.36 full torque static fuel produces 587HP. Arrangement number 128-7032 and performance spec 2T-8212.

takes forever to spool that big ### charger fact is it’s all it wants.

so back to you ain’t gonna have to run it at 2150 all night. Well to get the air out of the charger you gonna have to run yes your gonna need RPM. Yes more displacement will spool a bigger windmill easier or sooner however you want to say it. But remember your running an 18liter piston that’s had pin placement moved to a shorter stroke rod. So your gonna need a mill that spools faster but still cools….well you can’t get exactly both your gonna have to find that happy medium.