440 Six Pack cam specs were the same as the 383 and 440 Magnum (0.450-/0.458-inch lift, 228/241 duration at 0.050) but had unique rounded lobes. 95% of issues with POR15 is user error, to damp, to cold makes a pour finish.

@moparconnection

5 ай бұрын

You’re the first to say the A12 cams were the same; all other information says otherwise. The 69.5 A12 cam was NOT the same as the ‘70 and ‘71 440 Six-Packs.

@rtraymond

5 ай бұрын

@@moparconnection the only difference is the lobs had a different had a more "pitch" to rotate the lifters faster, and I think Hemi spec valve springs

the black spring is used in servere duty police prosuit,motorhomeand some hp applications. half narrow grooved upper main bearings and higher lift cams. that will have plenty amount of torque. a rv cam is plenty.

@moparconnection

5 ай бұрын

The RV camshaft is a DOG. Don't listen to this kind of negativity.

The machine shop called me the other day- Brian asked "Was this engine built by somebody?" I told him it was an 88K mile original, ran really well. He was very surprised...the machining from the factory was complete trash. The block had to be decked so much that the new pistons had become pop-ups, so he instructed me to get a set of Cometic MLS head gaskets at 0.060 thickness, and that will get my compression (with a '308' casting, '90 heads) to a more livable 9.45-1 CR. I got a chance to ask Herb, Jr (McCandless) his thoughts on my combo and he told me that the 318 will easily make within 20 hp of a 340, but the machining/exhaust (TBS headers, 2.5" dual exhaust with an X-crossover)/intake combo of Edelbrock Performer RPM & TQ will get it very close.

@moparconnection

5 ай бұрын

Yes! I’ve heard some serious horror stories about factory machining being seriously botched.

You may have benefitted from a call to Mr Six Pack. He makes 500hp with a smaller flat tappet cam and stock exhaust manifolds. His car pulls so hard off the line it near pulls a tire. Sounds stock at idle.

@moparconnection

5 ай бұрын

Very cool! But the goal wasn’t so much high horsepower but big torque at low RPM and avoiding flat tappet lifters given how often they’re failing these days. I’ll certainly check him out.

@dbc105

5 ай бұрын

@@moparconnection His engines make big torque. That 500hp is all in by 5500rpm. He was a Chysler engineer for years and knows how to make a MOPAR go. All the 6pk cam specs I've been able to find has the cam with pretty much Magnum specs but the taper on the lobe was different requiring a lifter with a special face.

Kevin... Its just and old stock engine build.. Then proceeds to install a crank windage tray and a roller cam. and Nitrous under the seat ;0)

@moparconnection

5 ай бұрын

LOL what’s so special about a windage tray? 🤣

As a novice and having never built a complete engine...ever, I wanted to make sure I heard and saw everything here. My question is....the ring end gapping ONLY pertains to the top ring and not the top and middle ring?

@moparconnection

5 ай бұрын

The piston manufacturer does have recommendations for gapping the second ring; ours - like many others - didn’t require filing. But it’s always good to check.