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Discussion Starter #1
I had a Comp camshaft 31-218-3 installed in my wife's cougar.
Installed in 1998 less than a 1000 miles on Engine. She drives a truck.
Problem has always been low vacuum and very hard braking until I
installed a crane Vacuum Reserve System.
Can't find any Info on the cam,today I found out I wired it for a 302

I thought it was a 351 Windsor Hi Per cam
They make a 31-218-2 for a 302 that they say will not effect power
brakes.
Wife is upset because it was running,now I have the distributor
out and the Ignition wiring.
I tried wiring for a 351 it will not run smooth,so I rewired for a 302,it lopes some what.
Points were bad so no harm done. I have a rebuilt power brake booster
and have check for vac leaks. It stays about 10-12" I think, been 13 yrs since I messed with it (w/o the Crane system).
The shop that built our engine is no longer in business,so I don't know
if they used a 302 or 351.

Bottom line I think I understand a 351W cam wired for a 302 would run ok.
Any thoughts? It bugs me to think I needed the Reserve system.
If Comp can tell me what the cam is,I hope. If it's a 351 I think I'll pull it out.
I'm not sure if I need new lifters with very little mileage.
 

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Well, you are correct in that a 351W cam will run fine in your 302 as long as you change the firing order to match a Windsor. Many claim and feel (myself included) that the 351W cams run better due to an optimized firing order. It's rare that I will ever use the old 302 cam in anything. However, they still run fine and make good power with the 302 cam in it.
To answer your question on lifters, absolutely put new lifters in it, the cam has already established a wear pattern and with today's crummy oil and a flat tappet cam, it'll destroy it.
If you do need a cam and lifters, I have a very nice low mileage cam and lifters (302 order) made good power, a little lumpy idle, and worked with my power brakes just fine....
 

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Discussion Starter #3
Well, you are correct in that a 351W cam will run fine in your 302 as long as you change the firing order to match a Windsor. Many claim and feel (myself included) that the 351W cams run better due to an optimized firing order. It's rare that I will ever use the old 302 cam in anything. However, they still run fine and make good power with the 302 cam in it.
To answer your question on lifters, absolutely put new lifters in it, the cam has already established a wear pattern and with today's crummy oil and a flat tappet cam, it'll destroy it.
If you do need a cam and lifters, I have a very nice low mileage cam and lifters (302 order) made good power, a little lumpy idle, and worked with my power brakes just fine....
Yea but I didn't change the firing order to a 351,so I guess they gave me a 302 Cam?
Have at least 1000 miles on the engine,if it was a 351 Windsor it should have run terrible?
The cam I bought was not stock. Thanks
 

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I found a listing for a Comp Cams 31-218-2. High Energy 268. .456/.456 lift, 268/268 adv dur, 218/218 @ .050. 1500-5500rpm Excellent in daily driver, slight mild-choppy idle. midrange power, slightly lower gears.

Oh, and yes, it is a 302 firing order cam! 351W- firing order has a 35- prefix
 

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Discussion Starter #5 (Edited)
I found a listing for a Comp Cams 31-218-2. High Energy 268. .456/.456 lift, 268/268 adv dur, 218/218 @ .050. 1500-5500rpm Excellent in daily driver, slight mild-choppy idle. midrange power, slightly lower gears.

Oh, and yes, it is a 302 firing order cam! 351W- firing order has a 35- prefix
Thanks a bunch, I have been having vacuum issues and thought they
installed a 351W My receipt says Com 31-218-3 there is no record of -3
I had wired it for a 302
My question is: if it was a 351W it would run rough right if I wired for a 302
Mine runs smooth with a mild lope
Thanks
 

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You can double check it by removing the valve covers and watching the rocker arms. Note the pattern the intake valves open by cylinder number and you've got your firing order for sure.

The answer to your question is: It will run poorly.
However, like any other manufacturing business, people have off days and things get the wrong part number on them, are boxed and labeled wrong, etc. So, it's possible that your mechanic ordered the cam and installed it thinking it was what he ordered because the box said so but really it's something else entirely.
So, there's that.

The only way to be sure, is to be sure by checking it out. At least when you have old parts, no receipts, and are standing there scratching your head wondering. You just gotta roll up your sleeves and do the work to be sure, or just set the wires where you like them and cross your fingers.
Since you have a receipt with a number, I would call Comp and ask them to look in their archives and give you the deets on this one before I did anything else. It'll probably take 10 minutes of your time, if they still have the data.
 

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Discussion Starter #7
You can double check it by removing the valve covers and watching the rocker arms. Note the pattern the intake valves open by cylinder number and you've got your firing order for sure.

The answer to your question is: It will run poorly.
However, like any other manufacturing business, people have off days and things get the wrong part number on them, are boxed and labeled wrong, etc. So, it's possible that your mechanic ordered the cam and installed it thinking it was what he ordered because the box said so but really it's something else entirely.
So, there's that.

The only way to be sure, is to be sure by checking it out. At least when you have old parts, no receipts, and are standing there scratching your head wondering. You just gotta roll up your sleeves and do the work to be sure, or just set the wires where you like them and cross your fingers.
Since you have a receipt with a number, I would call Comp and ask them to look in their archives and give you the deets on this one before I did anything else. It'll probably take 10 minutes of your time, if they still have the data.
I emailed Comp they said they have no record of a Com 31-218-"3"
O well it ran good just low vacuum and I had to add a Crane Vacuum Reserve System
I think I'll disconnect and plug off all lines and check the vac after I replace
the points ck the dwell and timing. Thanks
 
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