Yes you do need new springs. The mamba will rev to 8,000 with the 26 pound springs that it needs . The cam really doesn't start making power till close to 4,000 . So with the stock springs you will start making power and then float the valves at about 5,500 or so . What I'am saying is you'll have a motor that has about 2,000 useable RPM's of motor .
Just get the right springs in when you build it and all will be good.
Just get the right springs in when you build it and all will be good.
I just put a Black Mamba cam in my predator hemi and found it hitting the crank. To fix it just remove the crank , to do that remove the piston also cause the crank won't come out if you don't.
My cam was hitting the crank on the edge of the journal. I just taped up the journal and grind the edges , worked great. good luck.
My cam was hitting the crank on the edge of the journal. I just taped up the journal and grind the edges , worked great. good luck.
Just put the springs in right away cause you dont want to float a valve and hit the piston putting a hole in it.
Springs are cheap and not hard to install. I modified a large c clamp. buy the split keepers and alum retainers for the springs.
The stock retainers are junk, the split keepers are like auto keepers.
Springs are cheap and not hard to install. I modified a large c clamp. buy the split keepers and alum retainers for the springs.
The stock retainers are junk, the split keepers are like auto keepers.
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do yourself a favor and just got for the 37 lb springs. i bought a race head loaded with 28lb springs an ended up floating them and junking a race head. Later talked to the vendor for a replacment head and he said they have had a few issues like that and no all the heads they order have 37lb springs in them, these were NR heads as well.