billet rod, meet black mamba cam.

[isaiah3g]

So I've done a combination of about 6 of the hemi motors with stock, 20, and 40 thou longer rods.

I ran into a problem with the 40 thou longer rod hitting the middle of the cam between the lobes.

Eh....anyone else have this problem?

 

[isaiah3g]

Just swapped the rod for a stock length billet rod. Still hits.

:-/

 

[isaiah3g]

Having a conversation with myself here....

I swapped the BM cam into another all stock hemi I have. Same problem. It's actually hitting the crankshaft.

 

[Txpowdercoater]

im following along, just dont have any advice

 

[stephensimmons]

Having a conversation with myself here....

I swapped the BM cam into another all stock hemi I have. Same problem. It's actually hitting the crankshaft.

Can the rod be clearenced? Pics of the problem?

 

[isaiah3g]

Having a conversation with myself here....but I figured the problem with some help.

the crankshaft rod journal shoulders are slightly larger on the newer hemis. So they hit the lobes on the cam.

I swapped the BM cam into another all stock hemi I have. Same problem. It's actually hitting the crankshaft.

 

[isaiah3g]

Well that was odd. It copied what I was saying in an earlier post. :-/

 

[isaiah3g]

Where we live they refuse to run interent. All we have is our phones for Internet.
I can't post pictures with my phone to this site

Sorry


I'll have to shave on the rod journal shoulder

 

[stephensimmons]

Having a conversation with myself here....but I figured the problem with some help.

the crankshaft rod journal shoulders are slightly larger on the newer hemis. So they hit the lobes on the cam.

I swapped the BM cam into another all stock hemi I have. Same problem. It's actually hitting the crankshaft.

So you need to clearance for the crank then?

 

[stephensimmons]

Where we live they refuse to run interent. All we have is our phones for Internet.
I can't post pictures with my phone to this site

Sorry


I'll have to shave on the rod journal shoulder

Got ya

 

[vwfan79]

Use the app tapatalk, I upload photos to the site from my phone all the time.

 

[Txpowdercoater]

ive heard of clearanceing the cam lobe itself, if I remember correctly, its probably hitting the exhaust cam lobe and some have removed part of that while still leaving the shape/ profile

 

[vwfan79]

I would clearance the crank, anything taken off the cam lobe will change its profile. The crank can be clearanced with no ill effects.

 

[Txpowdercoater]

I would clearance the crank, anything taken off the cam lobe will change its profile. The crank can be clearanced with no ill effects.

not if its hitting the edge of the lobe, you basically make the lobe narrower a smidgen, still retaining same profile. w/o pictures, I'm guessing ...but I think thats what I have heard to solve the issue, just basically shave the one lobe wall down to clearance. removing metal from the crank changes balance, not that its precise now, but still....

 

[vwfan79]

I see what your saying, I would just prefer to clearance the crank then the cam. It's a predator your not gonna notice a little more vibration. Lol.

 

[SnakePliscan]

Crank to cam interference with predator and black mumba

Having a conversation with myself here....

I swapped the BM cam into another all stock hemi I have. Same problem. It's actually hitting the crankshaft.

You are using a clone BM cam right? not a Predator BM Cam?

 

[Prowler08]

Must be just the newer Hemis... I got 2 bought last year 2014 with a 307, 308, and a 330 cam and all clear without a problem...

Depending on how much you have to take off it is better to clearance the crank. If you narrow the cam too much it will leave wear marks and possibly lead to premature lifter wear...