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Discussion Starter #1
Is it possible to get a custom ground cam for a 6bt P pump and use it on a 4bt?
Hamilton does custom cams and I was wondering if there was a easier accessible and cheaper option since 4bt p pumps are hard to come by.
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NO

You need to understand the difference between 4 cylinder and 6 cylinder. For instance, valve opening sequence, cam shaft length...
 

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Discussion Starter #3
I'm well aware of cam, crank sequences, and injection sequences... I'm wondering if I can get a custom cam for a 6bt injection pump ground to work for a 4bt. Such as the first 4 lobe orientation of the 6bt injection pump cam would be the same as a 4bt injection pump and the last 2 which would be unused would be ground round.
 

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[QUOTE="1978FordF150, post: 1067074, member: 132545"
I'm well aware of cam, crank sequences, and injection sequences...
[/QUOTE]
I'm trying to be as polite (i.e Politically Correct) as I can be....) You may be aware of "cam, crank sequences, and injection sequences", BUT, you need to understand how they work.

Short summary:

The injection pump turns at 1/2 the crankshaft (engine speed) - the following refers to the rotation of the injector pump.

The 4bt injection pump produces injection events at 0 degrees, 90 degrees, 180 degrees and 270 degrees.

A 6bt injection pump produces injection events at 0 degrees, 60 degrees, 120 degrees, 180 degrees, 240 degrees and 300 degrees

Your proposal of grinding the last 2 injector cam lobes smooth would produce: On time injection, out of time injection, out of time injection, on time injection (with clever rerouting of the injector hoses), no injection and no injection.

Please do not take this as a "put down" - I am 75 years old and there is still a lot of stuff that I do not understand.
 

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Discussion Starter #5
Yeah exactly but instead. I'd call a custom cam grinding company to make a 6bt p-1700 cam and have them grind or build up the old cam/crank and have them grind to the following:
1st: 0° lobe
2nd 90°
3rd 180°
4th 270°
5th no lobe
6th no lobe

No rerouting lines just changing the orientation of the lobe profiles
 

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That is beyond my pay grade...
 

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Yes, you can, money conquers all. What are the other two lobes for? Wiper fluid, fuel pump?
 

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First off, you can buy a used 4bt P7100 for a little over $1600. The idea of just using 4 ports out of 6 on a 6bt pump might can be done. One issue you have to consider is will the pump physically fit on the 4bt. Not a lot of room between a 4bt P7100 pump and the fuel filter as it is. You may need to relocate the fuel filter, create new plumbing, and come up with a pump brace for that larger injection pump. Here's a link to the used pumps. Bosch Cummins 4bt P7100 on road P pump 4 cylinder on road useable injection pump | eBay
 

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Drifter? I would think just buying or sending the cam in would be a lot easier. But interesting idea for the ww fluid Red. Several places sell/regrind cams for the 4 popper.
I'd pay to see if you get it to work..
 
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