L-100 cam in a 221

Yoyodyne

Yoyodyne

Well-known member
I've been forced to rethink the motor I've been building and will start over with a 36LB block with maybe .030 overbore and stock stroke. I'll be using stock 36 aluminum heads. I plan to optimize the CR with .040 piston to head clearance and milling the heads. I have a Fenton 2 carb manifold and 2 Holley 94s. I also have an L-100 cam.



I've had other engines with a lot of cam and not a lot of compression, revving something to make it work is not a new experience, I don't need a torque monster to have fun. This is going into a 36 pickup with 3.78 gears and a stock 39 trans, just for occasional local fun.


Will this cam work OK in a 221?


Would porting the block be important in this combination?
 
I've probably built more engines than anyone else with the L-100, it was the goto cam. However they didn't run well in a small engine especially in a heavy vehicle . But they do sound good. Why not the 1007b, sounds good and would probably run better.
 
Yoyo, I've built and run numerous 221's, including the L100 and Fenton twin as you're proposing. I agree with Ron; the L100 is not a good cam in this application. Try an Isky 88 cam along with your other mods, take the lip off the flywheel, use a 9" clutch, and yes, port the block. The idea is to lighten everything as much as possible and allow the thing to breathe. Enjoy...
 
Ol' Ron said:
I've probably built more engines than anyone else with the L-100, it was the goto cam. However they didn't run well in a small engine especially in a heavy vehicle . But they do sound good. Why not the 1007b, sounds good and would probably run better.
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This would be my choice in cams . . . but there are plenty of ways to "skin this cat".
 
Thanks for the knowledgeable recommendations! A quick search shows isky cams only for 42-up, would I have to give up the 3 bolt distributor and front plate?
 
The L 100 need compression and cubs to build the torque lost to a long cam. Thus you have a streetable cay. The 276 does this.
 
Yoyodyne said:
Thanks for the knowledgeable recommendations! A quick search shows isky cams only for 42-up, would I have to give up the 3 bolt distributor and front plate?
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I've had Pete grind some 1007B profiles (and a lot of others) - he does extremely nice work. Also Kiwi Tony grinds a lot of cams and is highly respected on the Ford Barn world (though I don't know what masters he has).

Truth be told, I'd rather have a stock cam reground these days than buy a "new" one. But hey, that is just me . . .
 
Since Pete is here, what is the acceptable smallest diameter for cam journals to reuse? I checked the 3 I have, they range between 1.7955/1.797.


What do (or should) installed cam bearings measure?
 
Cam journals measure between 1.796-1.797". Wear limit is 1.795" Clearance in brgs is .002"
this is what i do; Install .010" undersize cam bearings. Measure the installed dia of each bearing. As a reground cam is ground between centres, I put the camshaft between the same centres and grind the journals to suit the installed bearings. Do not assume that .010" bearings, when installed will measure exactly .010 u/s! Doing it this way ensures perfect concentricity of the camshaft journals and lobes, also, I am assured the correct clearances are in place, with no resultant loss of oil pressure through sloppy clearances.
 
Yoyodyne said:
Since Pete is here, what is the acceptable smallest diameter for cam journals to reuse? I checked the 3 I have, they range between 1.7955/1.797.


What do (or should) installed cam bearings measure?
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For clearance, I run .002 on street engines and .003 on race engines.

I use 1.795 as a minimum as long as it is round.
 
Ol' Ron said:
Where do you get under size cam bearings.??
Gramps
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Most of the new parts sellers have them, they are currently made. I have a set I don't need now.



Brian said:
Cam journals measure between 1.796-1.797". Wear limit is 1.795" Clearance in brgs is .002"
this is what i do; Install .010" undersize cam bearings. Measure the installed dia of each bearing. As a reground cam is ground between centres, I put the camshaft between the same centres and grind the journals to suit the installed bearings. Do not assume that .010" bearings, when installed will measure exactly .010 u/s! Doing it this way ensures perfect concentricity of the camshaft journals and lobes, also, I am assured the correct clearances are in place, with no resultant loss of oil pressure through sloppy clearances.
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I had Dave Generous grind my L-100. The only usable core I had at the time was worn undersize and needed the journals ground. Dave said he couldn't do it on his grinder, he wanted me to send it elsewhere first to have that done before he ground the lobes. That's when I bought this set of .010 bearings. I found a the cores I have in parts engines since then while looking for a good block.
 
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