Been awhile since I posted but I'm currently in the operation of upgrading from HP manifolds to hedman shorty 78070 headers on a 69 Charger. It's been a battle so far I had to take the bolt off the motor mount on the driver side lift up the engine one inch, remove the mini starter and I'm currently battling the installation of the header. I have a fitment issue because I have performer RPM heads on this 440 and it seems that the flange of the header is hitting the head stud at the far front of the engine and at the far rear of the engine. Has anyone installed this can you give me a pointer or two. I'm looking at the flange and I might have to grind off about a quarter of an inch at the front and another quarter of an inch at the rear to clear the head bolt. For what it's worth I'm going to be using Remflex gaskets and split lock fasteners for the headers.

The only other fitment issue I'm having is the oil dipstick tube is in the way I had to disconnect it from the ear under the number 3 cylinder.

I have tti headers with Trick Flow heads and ARP head studs. And yeah I ended up cutting off about the top 1/4” of the 2 head studs nearest the corners of the engine. After that everything fit okay, also using Remflex 6002

6002 yeah.. That's the same gasket i have

I'm weary about cutting the head studs. 😱

Isn't it better to cut the flange a little?

Yeah, I was like I’m not grinding on my brand new $1000 headers, I would have done it if grinding the studs wasn’t enough. I definitely measured twice and cut once and made sure threads were showing above the nut afterwards. I “set” the depth of the cut using two nuts jammed at the right height on the studs. The nuts acted as a guide and protected the threads

i have a 440 with rpm heads, and i'm using a set of tti 2" to 2 1/8" step headers.
these heads are using arp bolts instead of studs, and the bolt heads only have about 1/8" clearance around the header flange, so i can see where using studs would be a problem.

I unfortunately buttoned her back up with the HP Manifolds again. All that work to discover that. I didn't want to cut the studs. I chamfered the flange at #1 & #7 but then soon discovered that the studs began hitting #3 & #5 and just surrendered. I have to order a set of ARP bolts but since I live in Europe, the shipping time enters the "weeks" not "next day delivery".

Oh well...A winter project ahead

Even with the head bolts you may have to slightly grind the flange or use 2 gaskets, like I do.