Cam wiped out, what the hell did I do wrong?!?!?

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moper said:
64, what year is the block?
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Think it was a '78. I'd have to double check to be sure. I bought 2 at the same time, and one was a '78, I forget the other, but seems like it was late '70's also. One was out of a tow truck, and the other out of a truck or van also.
 
dodge freak said:
Stroke motors do like lots of cam, however many say its better to error on the smaller size. This cam here in a 360 would be a hot street profile. Check out the lift, like .550 and its a hyd roller cam by
CROWER f

STREET ROLLER / PERFORMANCE LEVEL 4 - Excellent street strip profile.
RPM Power Range: 2500 to 6000 / Redline: 6500 plus


31406

270R

112°


Duration 270-280

Duration @ .050 int 236 ex 246

Lift .550"-.548

with 1.5 rockers...says nothing about using 1.6 rockers, let alone 1.65
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Looks good, but I was always told that on small block Mopars, you want more lift on the exhaust. Maybe the extra duration on the exhaust would make up for it. Looks similar to one of the Comp cam profiles I was looking at earlier, but it was on either a 108* or 110* LSA. I haven't even checked out Crower yet.
 
This is from Comp on Ebay, they sell their used and less than perfect cams on ebay...all very usable. Again way less lift. I would break in the cam using 1.5 rocker arms.

http://cgi.ebay.com/ebaymotors/COMP...r_Truck_Parts_Accessories&hash=item19bde1f393

Cam Style Hydraulic flat tappet
Basic Operating RPM Range 2,300-6,500
Intake Duration at 050 inch Lift 240
Exhaust Duration at 050 inch Lift 246
Duration at 050 inch Lift 240 int./246 exh.
Advertised Intake Duration 284
Advertised Exhaust Duration 296
Advertised Duration 284 int./296 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.507 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.510 in.
Valve Lift with Factory Rocker Arm Ratio 0.507 int./0.510 exh. lift
Lobe Separation (degrees) 110
Intake Valve Lash 0.000 in.
Exhaust Valve Lash 0.000 in.
Computer-Controlled Compatible No
Grind Number CRS XE284H-10
Quantity Sold individually.
 
Ah. I thought it was a later block allowing for factory hydraulics. In any event... In terms or cams, you want what the heads will work with. With stock heads and a full exhaust the trend was to give it more duration and a little more lift. I still believe that's needed, at least the lift part. But many cam companies are spec'ing shorter durations and less lift, but timing the lobe's opening and closing ramps better with piston motion so the piston pushes out the exh when the piston and crank have maximum speed and pressure. Then the cylinder is sealed to allow for a better intake fill with less overlap and wasted intake charge out the exh. If you are going custom, then that is the route I'd be advising you go. Truthfully you need to know what the heads flow before you get too concerned with getting "the perfect" cam. As without accurate flow information we're all just guessing with some experience.
 
moper said:
Ah. I thought it was a later block allowing for factory hydraulics. In any event... In terms or cams, you want what the heads will work with. With stock heads and a full exhaust the trend was to give it more duration and a little more lift. I still believe that's needed, at least the lift part. But many cam companies are spec'ing shorter durations and less lift, but timing the lobe's opening and closing ramps better with piston motion so the piston pushes out the exh when the piston and crank have maximum speed and pressure. Then the cylinder is sealed to allow for a better intake fill with less overlap and wasted intake charge out the exh. If you are going custom, then that is the route I'd be advising you go. Truthfully you need to know what the heads flow before you get too concerned with getting "the perfect" cam. As without accurate flow information we're all just guessing with some experience.
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ditto.
remember physhy...you have ported aftermarket heads that should NOT be crippled/disadvantaged on the exhaust, like a stock head.
 
Hey it looks like to me was the line up of the cam set in too far into the block, the lifters have to line up in order to get the lifters to rotate. It does not take much to wipe out a cam. My dad raced in the sixies all we ran was mechanical cams. Only once was he concerned about the line up of the cam. Also without the oil holes lining up you could have starved the cam for oil. Also the oil runs down the pushrod if the oil was not getting to the rockers you cuold have starved the cam for oil. Sorry bout that. Im getting a lot of info that Ive forgotten throughout the years by reading about others. Again Im deeply sorry.
 
cuda2ya said:
Hey it looks like to me was the line up of the cam set in too far into the block, the lifters have to line up in order to get the lifters to rotate. It does not take much to wipe out a cam. My dad raced in the sixies all we ran was mechanical cams. Only once was he concerned about the line up of the cam. Also without the oil holes lining up you could have starved the cam for oil. Also the oil runs down the pushrod if the oil was not getting to the rockers you cuold have starved the cam for oil. Sorry bout that. Im getting a lot of info that Ive forgotten throughout the years by reading about others. Again Im deeply sorry.
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due to the design of a SB Mopar there isn't much you can do about where to install the cam (in reference to how far in it goes). Once you slide the cam in and bolt on the thrust plate and timing gear it's held in place by those items. If the lifters were out of alignment it would have to be either a defective cam or a lifter bore problem.
 
Man, a 426 hemi weighs 800 pounds?? Sheeeeeeeeesh.

Another advantange to hydraulic rollers is that you don't have to sweat swapping the headers after break in to avoid damaging the coating.

Of course, you get that same advantage by using an engine dyno/break in stand.

Steve
 
brewil said:
Your one lifter looks chipped and damaged
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There are several lifters that are extremely chipped and damaged. One is about 1/8" out of square at the end. Another has a step wore in it, which has me thinking maybe the cam didn't sit in the block in the right position.
 
did you check to see if everything in the front of the engine...timing chain...cam thrust plate are all ok?
 
70aarcuda said:
did you check to see if everything in the front of the engine...timing chain...cam thrust plate are all ok?
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They all looked ok, but as tight as the bearings are, I'm going to replace it anyway just in case the chain got stretched or stressed.
 
Here are some pics of the bad lifters and lobes.
The second and fourth bearing journals were also slightly scored. Looks like the hole on the 4th wasn't totally lined up. Also looked like the cam sat to the rear about 3/32" because the lifters were not centered.

0720101955.jpg


0720101957.jpg


0720101959a.jpg


0720101959.jpg
 
The lifters were not centered because they are to rotate as they lift. That is how the cam should be!

I still believe the cam with the 1.65 rockers were just ask to lift too high, too fast.

Here is a cam on ebay right now for a 500 ci bbm, check out its specs and lift.

Nitrided Comp Cam Custom Grind for Big Block Mopar 383/440 with Solid lifters inc/Oil hole
http://cgi.ebay.com/ebaymotors/Comp...iewItem&pt=Race_Car_Parts&hash=item20b243ed6b

Designed and consulted Expert Dwane Porter (Porter Racing Heads South Burlington, VT (802) 951-1955 Dwayne) for Custom Grind for my Mopar 500 Stroker

1.) Comp Cam - MOPAR Big Block 383 440 SOLID RACE Aggressive Grind *****NITRIDED*****
2.) Comp Cam Solid Lifters with Oil Hole

Valve Adj .020 .020
Gross Valve Lift .550 .556

Duration @ .202 Tappet Lift: INTAKE=287 Exhaust=291

Cam Installed Specs @ 106 Intake Center Line
INTAKE Exhaust
Duration @ .050 256 260
Lobe Lift .3670 .3710
Lobe Separation 110.0
 
tapper of the lobe is what rotates them.

guys how many flat cams have you seen?

once they start to go, there will be no more rotation and they end up looking like this especially if it's been run even more after 'break in' [literally], they will eat themselves.

I can come out to look at the block and we can mock up the cam/lifters to see whats really what.
I have a strong feeling it aint the block thats off.
 
So improper break in combine with a too aggressive lobe for a street motor--IMO. A cam like that should have an idle speed of min 1,500 rpm. That is another thing, slow idle speeds can kill cams. The slower the cam turns the harder it is on the lifters and the less oil gets thrown up from the crankshaft.

Real race cars "idle" at 2,500 rpm's. Race cars run cams like this one, not a street car-again imo.

I would clean everything up and email-call Comp Cams and plan on getting a custom cam made and let them pick it. Explain what happen and use break in valve springs next time. Hughes should make it more of a point how to run a very aggressive cam like their grinds. I am sure Hughes cams will squeak out the most power but there are compromises to be made-like fast idle speeds.
 
1wild&crazyguy said:
tapper of the lobe is what rotates them.

guys how many flat cams have you seen?

once they start to go, there will be no more rotation and they end up looking like this especially if it's been run even more after 'break in' [literally], they will eat themselves.

I can come out to look at the block and we can mock up the cam/lifters to see whats really what.
I have a strong feeling it aint the block thats off.
Click to expand...

Are you talking about mocking up the new cam and lifters when I get them, or the old ones? I don't remember what came out of where. I didn't mark it because it's not going back in. Might be able to match the wear on the lobe with the wear on the lifter, but the lifters in the pic only come out from the bottom of the bore.

Also, I don't think I mentioned it, but the 2nd and 4th journals and bearings were scored, and I think it was the 4th the hole wasn't totally lines up when I took it out, but I'm sure they were before I installed it. I think it moved somehow from the friction or when I was muscling the cam out.

I still haven't pulled the block yet to tear it down, and probably won't be able to get to it until weekend after next.
 
DF your looking at it too deeply, I agree taper on the lobes is what makes the lifters rotate, i don't know of ANY race engine that idles at 2500 rpm , may be a hi-perf rotary? And they do not need to be splashed with oil from a rotating crank. After all thet are in direct contact with oil bleeding from the oil galleries as well as oil from the lifter galley. IMO its either defective cam cores (made in China?) or too much valve spring pressure. Oh i was a cam grinder when Racer Brown was in Sun Valley, Ca.
 
W2, there is very little oil bleeding out of the galleys if things are in spec, and the oil from the valley typically flows around the lifter bores, not over them. Much more oil comes from splash off the crank than you are giving credit for. That's the real source of oil for the lifter faces when there are no EDM holes in the lifter face. As far as idle speeds, I know of many racers that keep the idles between 1200 and 1500 just because of the cam and they limit the idle time. I dont know any that go higher but there probably are some. IMO, a race car can idle wherever but for a street car I don't go above 900 and normally they are 750-850rpm so those ultra-fast lobes just aren't worth it to me.
 
I don't believe low rpm idle killed this hughes [small in the line up they offer] cam.

but it would be nice to hear from all the guys who supposedly run hughes cams...

where you guys at??


btw r there any pinched seals?
I would like to measure the installed spring height and then put the springs on a rimac to see what they really are.

I will say this...it is my opinion that when you are running on the high side of spring pressure, to run it in at the high side of the break in rpm like 25-3000 rpm.


honestly, I have run 165 psi doubles and only angled/flat spotted 2-3 lobes on a 3742 solid hughes.
this looks WAY worse than that...so it's got me wondering.
 
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