Camshaft wont fit

-
clv22p

clv22p

72 Dodge Demon 340
Joined
Feb 2, 2012
Messages
301
Reaction score
53
Location
Nashville, Tennessee
Just curious if anyone else has ever had this issue? I had a comp XE284H in my new 340. Had about an hours worth of run time on it. I pulled it out because it was way to much cam for what I wanted.

I decided to put in a Mopar Performance 284/484. When I put the cam in and bolted down the cam retaining plate the camshaft wont turn. If I put the timing chain sprocket on I can turn it but it is really hard.

Mopar is sending me another cam, but I am just wondering if anyone else has ever had this issue.
 
Cam maybe bent. I can tell you that the 284/484 cam will run as rowdy or rowdier than the Comp you removed. That actual measured advertised duration on the MP cam is 290*. If you got the 112 LSA version it might be a little more friendly.
 
as long as you are using a moly lube and you can turn it by hand with the sprocket, it will be fine. it will loosen up the second you fire the engine. run it... Ive had the same thing happen a few times and they all enjoyed a healthy life..
 
73AbodEE said:
as long as you are using a moly lube and you can turn it by hand with the sprocket, it will be fine. it will loosen up the second you fire the engine. run it... Ive had the same thing happen a few times and they all enjoyed a healthy life..
Click to expand...

This ^^^
 
Those two cam from a duration at .050 standpoint are not much different.
 
I'm a stickler. If I can;t turn the cam by hand with the bolt in the end, there's a problem and i find and fix it. Normally it's the bearings having a small shoulder worn from the earlier cam - not a big deal to fix. But knowing MP - I'd check the cam in some V blocks with a dial indicator. If it's straight clearance the bearings.
 
Wanna bet? If you map that MP cam, no way in hell will it come up 241. They never do.
 
The two cams in the first post. Please note my post and your followup with a "different" cam were the same time.

Mopar SB's are pretty bad on cam tunnel sizing...

Good luck
 
moper said:
I'm a stickler. If I can;t turn the cam by hand with the bolt in the end, there's a problem and i find and fix it. Normally it's the bearings having a small shoulder worn from the earlier cam - not a big deal to fix. But knowing MP - I'd check the cam in some V blocks with a dial indicator. If it's straight clearance the bearings.
Click to expand...

X2. I had a new cam out of the box that was bent. A cardboard box plus having people toss these things around can cause some big headaches.
 
crackedback said:
The two cams in the first post. Please note my post and your followup with a "different" cam were the same time.

Mopar SB's are pretty bad on cam tunnel sizing...

Good luck
Click to expand...

I see that now. They are pretty close. But Im hoping the exhaust duration 241 (mopar) vs 246 (comp) will help.
 
clv22p said:
When I put the cam in and bolted down the cam retaining plate the camshaft wont turn.
Click to expand...

This may be a obscure thought, but does it turn ok without the retainer? Could the new cam be a hair longer for whatever reason? Could the rear cam plug be drivin' in too far for it. I know it's a rare occurrence, just throwing out the possibility.
 
what shape is your thrust washer, is your end play ok?
 
OldmanRick said:
This may be a obscure thought, but does it turn ok without the retainer? Could the new cam be a hair longer for whatever reason? Could the rear cam plug be drivin' in too far for it. I know it's a rare occurrence, just throwing out the possibility.
Click to expand...

When I set the comp and mopar can side by side the mopar is longer. It spins freely until I put the retaining plate on. The mopar litter ally just seems like it was made too long.
 
If it's that close to fitting, just knock the cam plug back out, re coat it with sealant and knock it back in not quite as deep.
 
The engine is in the car. Wont I have to pull the engine to get that cam plug back in? Id rather not do that
 
moper said:
I'm a stickler. If I can;t turn the cam by hand with the bolt in the end, there's a problem and i find and fix it. Normally it's the bearings having a small shoulder worn from the earlier cam - not a big deal to fix. But knowing MP - I'd check the cam in some V blocks with a dial indicator. If it's straight clearance the bearings.
Click to expand...

Read this (why my cam won't turn):

http://www.musclemotorsracing.com/muscle-mike-blog.html
 
airwoofer said:
Read this (why my cam won't turn):

http://www.musclemotorsracing.com/muscle-mike-blog.html
Click to expand...

I agree with Line Honing the cam tunnel. I did this on my last motor and it is without a doubt the easiest spinning rotating assembly I have put together to date. Cam in by itself you can spin it with 1 finger almost like it is on roller bearings. Even with the timing set hooked up spinning the entire assembly is like butter. I will never build another engine without having this done.
 
Yeah, I know the bores are tight in most of them and in some the bores themselves are not even in line... And I have the utmost respect for Mike and MM... But - in terms of my being picky - the cam has to turn easy. I am not building competition, no holds barred, grab every ounce fo power engines. You will not find much to read about the oil wedge on a cam bearing - or the oil clearance for that matter. The runout for camshafts is .005" allowable so what do you think the oil clearance is? Hell they get as much (or more) oil as the crank does! On a flat tappet engine with a cast cam core, factory lifter bores, and and lift under .700 I'd put money there is not measurable power to be found in honing the cam bores. I'd call it equal in importance to choice of hose clamp to use in terms of my needs. So - In my opinion I don't need to worry about how perfect the cam bearings fit. I've personally installed somewhere around 50 sets or so and I've never found one that fit that bad that I hadn't screwed up when I installed it...lol. Normally if anything I need to shave out a nick or high spot. If the cam can't turn - look at the guy that installed the bearings. I've watched "pros" not use the centering cone on the installer and that will make them impossible to work with.
 
Seen bores on the small/tight side enough to essentially oil can bearings. It crushes the bearing too much.
 
Yup - I've heard of it but never seen it. I have seen bearigns cocked in the bores, and bearings that got nicks in them that look like the factory put them there, and bearings that didn't line up with oil holes to the top end - but again - never seen (or did) anything that wasn't installer error and fixed by scraping the offending spot a hair. I've never needed to "resize" or cut the ID larger around the entire bearing surface. Only in small spots, and for some reason the #1, and #5 bearings mostly. As Mike points out - the bearings are consistent. If the installer is good, or the assembler is careful and checks, it's an easy issue to address. At worst case it's another set of bearings. I wonder what the cost would be if the person's shop didn't have the equipment to hone those bores vs another $40 set of bearings.
 
You must log in or register to reply here.
-

Back
Top