Hemi Head Mamba Cam Issues!?!?

[Grizzlymi]

Building a Hemi Head predator, first time using a Black Mamba cam, and the lobe is hitting the crankshaft. It's a GX200-Hemi cam so not sure what the issue is! Had a few barley pops looking it over and over again, and can't figure this out. Any help would be great!!!!

 

[minibikin']

predator cam


Sent from my Texas Instruments Speak and Spell...[emoji2]

 

[Grizzlymi]

Thanks for the reference minibikin, read through the forum and mine is the grind hitting the crankshaft, not the side. [emoji20]

It's not even close.

 

[bpoirier]

Almost all of the cams I've installed in the predator motors I've built lately have hit the crankshaft. I've had to take the crank out and grind the flashing and contour the end a bit to get the cams to clear.

 

[george3]

Is this only on the hemi version?

 

[FirePowerMinis]

Build vs assemble...

 

[minibikin']

I should elaborate. China made. Tolerances are all over the place. From deck height to clearances. Check them all and clearance as necessary...


Sent from my Texas Instruments Speak and Spell...[emoji2]

 

[Possom point]

I'm having the exact same issue, Exhaust lobe is hitting the top of crank to...... What all did u do s far as grinding the crank??? Does that change the balance of the crankshaft??

 

[xBrent92]

What lift is that camshaft is what i want to know.

 

[OND]

I think its 275 lift, and I run a Mamba Jr. cam in my Hemi 212 and had no problem with clearance .

 

[trinik7597]

yup 275 lift ... like ond said and just clearence it like minibikin said

 

[Grizzlymi]

Yeah, it's 275. Guess it's time to grind. Chinese engineering.......

 

[Newoldstock]

Yes the Chinese engineered it to use a stock cam lol.

Last engine I built I ground a lot of the crank, its not big deal as long as you are not trying to lighten it or do something silly too it that weakens the forging.

I even used to paint them....
After an acid wash to clean the pors of the steel I would paint them several times with a sanding in between until the surface was smooth and slick

 

[Twid]

What lift is that camshaft is what i want to know.

275!

 

[xBrent92]

275!

ha. you might as well put that in your signature.

and thanks guys, i guess i'll have to pick up some grinding stone while im out..just got the .290 woot!

 

[bpoirier]

I'm having the exact same issue, Exhaust lobe is hitting the top of crank to...... What all did u do s far as grinding the crank??? Does that change the balance of the crankshaft??

I use my dremel tool with a sanding barrel on it. You don't need to remove a lot of material so balance shouldn't be a problem.

 

[xBrent92]

i second what he said^ and the other guy saying it only needs a "little" bit ground off. literally a little. i mean grab your feeler gauge or picture about .50 and thats all you need to take off,maybe less that was just a guesstimate.

 

[FOMOGO]

picture about .50 and thats all you need to take off

I think you mean... .050... Not .50.. that's a half inch... Looks like made I that post. You should see all the fat fingered mistakes I make typing. Takes a couple of minutes for me to correct the spelling......

 

[xBrent92]

I think you mean... .050... Not .50.. that's a half inch... Looks like made I that post. You should see all the fat fingered mistakes I make typing. Takes a couple of minutes for me to correct the spelling......

oops.Yes i meant .050 . i hope noone ground off half an inch .

 

[Grizzlymi]

Thanks for the help everyone!!! Only took a little grinding with a dremel sanding drum to get it to clear.

It's hard to see, but it clears now. [emoji1303][emoji482]