Camshaft grinding

96blak54

Legend
Joined
Feb 21, 2011
Messages
8,020
Reaction score
1,292
Location
Ky
Here is my latest escapade.



For the last 5ish years. Ive been tinkering around building a camshaft grinder, mostly centered around grinding modular ford cams, but does accept any cam with nearly 30" length.

My first go at grinding i had it set up similar like an actual cam grinder. Using a grinding wheel to remove tge material only to find the difficulties of dressing the wheel after every lobe grind. Grinding wheels load up with material and need to be brought to square after each grounded lobe. Doing so posed time consuming process and not cost effective at all. Also the grinding wheel process wasnt smooth and required strong stabilization so that the wheel or cam doesnt bounce away when being ground. The bounce showed up into the grounded lobe, producing a ripple on the lobe. A softer grind wheel could be used to correct the ripple but again costs and keeping it dressed.

All mathematics and machine work to get the grinding wheel motor all situated, after much debate with myself, i scraped the idea in favor of a small mini belt grinder/sander.

Off to harbor freight to view a possible selection upgrade and luck would have it, they had one. $100 later and a few extra belts of different grades, i found myself disassembling parts not needed. Like the side mounted disc grinder and bottom mounting plate or the steady rest for the grinders.

A new mounting plate had to be made to adapt the belt grinder to the machines cross slide and i had to raise all of the camshaft mechanisms 4" with some aluminum blocks, so that the camshaft lobe meets the grinders belt backing plate. Turns out that backing plate was flimsy and after a few lobe grinds it had to go in favor of something solid. A few ours on the mill with some angle iron made all the difference. Now it grinds smooth and effortless and after each lobe, when the belt is worn, i simply replace the belt...$2.50. Ive since discovered i can grind 2 lobes per belt.

Each lobe with the pattern i have set takes roughly 25min to grind. 120grit belts prove to produce a real nice finish while helping to keep time spent to a minimum. Best of all, these belts are local and always in stock.
 

Attachments

  • 20210517_124400.jpg
    20210517_124400.jpg
    174.7 KB · Views: 6

96blak54

Legend
Joined
Feb 21, 2011
Messages
8,020
Reaction score
1,292
Location
Ky
A few mo pics
 

Attachments

  • 20210513_122626_HDR.jpg
    20210513_122626_HDR.jpg
    278.6 KB · Views: 7
  • 20210520_130832_HDR.jpg
    20210520_130832_HDR.jpg
    169.8 KB · Views: 7

96blak54

Legend
Joined
Feb 21, 2011
Messages
8,020
Reaction score
1,292
Location
Ky
You are probably wondering how i know what the grind pattern is afterwards or how i know what to grind off and where. Well....their are just some secret i wont reveal. Coming up with the pattern almost exactly how i wanted took a few lobes and sacrificed a few cams and after a few hours on the cam map station, im happy with to start with this pattern.

I build a cam check station a few years ago using an old head and a bunch of measuring gauges. Its basic, requires some time along with mathematics, but is repeatable and cheap.

You may remember the npi and pi camshaft thread? Thread 'NPI & PI cam specs' https://www.sn95forums.com/threads/npi-pi-cam-specs.72717/

A thread that we discovered not all 2v modular cams are the same like once thought. Findings revealed many npi grinds and many pi grinds. Long story short?.... Cams to look for is the actual mustang pi gt cams and the pi 5.4l cams. They are the best performers. The intake openings are .500" and the exhaust openings are .530". Whereas the other style cams typically found in the panthers, exploders, or 4.6l trucks lifts are .475" for both valves. Measuring the lobes max lift from base circle, subtract the base circle diameter then multiple the followers ratio of 1.8(some say 1.79) will result in max valve lift. This is the easiest way to tell what cam you have without part# searching.
 
Last edited:

joe65

Well-Known Member
Joined
Feb 4, 2020
Messages
1,219
Reaction score
1,102
are you in business or just doing this for your car/s and that kind of thing? I'll be looking for stock ground cams for my mach 1 before too long.
 

96blak54

Legend
Joined
Feb 21, 2011
Messages
8,020
Reaction score
1,292
Location
Ky
Its more of a hobby right now. It may lead into making a profit later. Im still learning the modular valve train even tho i feel like i have a good grasp on it. Also learning the limits of how much stock cams can be modified.

Not sure regound 4v cams would benefit you any. I mean its very much possible, long as youre willing to shim lashers. Truth be told 4v cams really dont need modifications. Just degree the exhaust cam back a good 8*(retard) thats 16* at the crank. Itll make the lsa roughly 108*.....give a few degrees. Youll gain over lap and will need a tune because of it.
 

Boostr1

Active Member
Joined
Apr 17, 2020
Messages
912
Reaction score
629
Location
North Jersey
You may remember the npi and pi camshaft thread? Thread 'NPI & PI cam specs' https://www.sn95forums.com/threads/npi-pi-cam-specs.72717/

A thread that we discovered not all 2v modular cams are the same like once thought. Findings revealed many npi grinds and many pi grinds. Long story short?.... Cams to look for is the actual mustang pi gt cams and the pi 5.4l cams. They are the best performers. The intake openings are .500" and the exhaust openings are .530". Whereas the other style cams typically found in the panthers, exploders, or 4.6l trucks lifts are .475" for both valves. Measuring the lobes max lift from base circle, subtract the base circle diameter then multiple the followers ratio of 1.8(some say 1.79) will result in max valve lift. This is the easiest way to tell what cam you have without part# searching.
Hmm, I wonder if this was the issue when I did a PI H/C/I swap. I had an issue with the lifters bottoming out, I had to take them to a machine shop to grind some material off the lifter bottoms for them not to bind. I wonder if that was due to the higher lift PI cams.
 

96blak54

Legend
Joined
Feb 21, 2011
Messages
8,020
Reaction score
1,292
Location
Ky
The lifter are suppose to squeeze down to a stop point at opening ramps and max lift. If their wasnt an internal spring like found in npi heads lashers and old 4v head lashers, the lashers return rate to base circle was to slow and relied totally on the hydraulic of oil pressure. This would have caused valve train rattles.
 

96blak54

Legend
Joined
Feb 21, 2011
Messages
8,020
Reaction score
1,292
Location
Ky
My lathes are a quarter size of those. Pretty neat to see crankshafts getting cut out. That one guy had vibration in his cut. Probably cause the center section of the crankshaft didnt have support and the cut was to big. Really neat tho
 

ttocs

Post Whore
Joined
Oct 9, 2009
Messages
27,923
Reaction score
3,722
Location
Evansville Indiana
My lathes are a quarter size of those. Pretty neat to see crankshafts getting cut out. That one guy had vibration in his cut. Probably cause the center section of the crankshaft didnt have support and the cut was to big. Really neat tho
its impressive to say the least.
 

Latest posts

Forum statistics

Threads
74,991
Messages
1,454,217
Members
13,624
Latest member
Thilton247

Members online

Top