[AROWHED]

Dumb question: What would be the differences in header design for 61-64 fullsize, versus 65 and up? I am unfamiliar with 61-64 fullsize. Mad Dog Headers has separate listings for these year groups, so there is obviously something significant. I called and he said could not do 2" primaries in round port for 65-up, but does have a part number for round port 2" for 61-64. Just gotta wonder how different they would be.

http://maddogheaders.net/

[64catdroptop]

Pontiac made some head design changes from '64 to '65, most notably 12 bolt to 10 bolt and I believe they changed the exhaust port design from O to D

[AROWHED]

The differences I'm primarily concerned with are the frame, steering components location, front suspension, motor mounts, starter, trans...anything that might interfere with headers. When I said round port above, that was in reference to Mad Dog's part numbers for Edelbrock or similar RAIV round port-headed engines.

[66bonne]

Sure would like to find some 2" primaries for 65-66 Big Cars. Mike: Thanks for finding out about the Mad Dog headers, I thought Doug's was our only source.

Jim

[AROWHED]

I asked Mad Dog the same question about possible fit differences between his part numbers 9146 and 9169 as far as fit goes, and the only reply was:
sorry not sure what the difference is (if any).

[Deadhead]

Always confidence inspiring when a vendor knows so much about his product.

[Engine-Ear]

Originally Posted by Deadhead

Always confidence inspiring when a vendor knows so much about his product.

Yep (LOL) ... but as I think about it, the trans-mounted starter is one issue. As Ron suggests, there could also be a difference in the angle of the plane of the exhaust flange between the two series, causing the collectors to be too far in- or out-board when put on the other series.

[Deadhead]

Right, so if I, a rank novice, can yank an engine and put it on a stand and manage to get the old manifolds off I would hope a vendor who has to have some liability insurance could do at least that.

Having had both, I would think that the early versions, if they would mate up with the ports, would fit at least as well in the bay. Seemed tighter in the '63 and they were a narrower track car.

How about long branches? Will they interchange? I know that is not what Arrowhead is looking at, but that would at least get him closer.

It is still mind boggling that somebody trying to sell something... We have an old relative who sold cardboard boxes. His opening line was always, "You don't want to buy any boxes do ya?" You can imagine the results. Just apply that phrase here.

Could ya set the two side-by-side and tell the difference? Do the bolt holes line up?

Lord have mercy.

[65WJ]

sometimes you cannot expect the person on the other end of the conversation to know everything little thing about ALL of their product.
I service Kyocera, Riso, Duplo and FP product. Hundreds of different products. I cannot tell you all the differences between all the products of each line.
Give the guy a break

patrick

[AROWHED]

I am going to meet up with another PY member locally soon, do a side by side underhood visual on his 64 Cat vs my 65GP, in an attempt to discern any significant differences in the areas that headers must squeeze through.
As for Mad Dog, Pontiacs aren't his only header make, and I know zip about his operation. I am a bit disappointed that no photos or other information are available even after requesting them, but if his headers are of the quality and good fit I've read about in here, that's 99% of what really matters to me. He did offer to take back anything that does not work.

[Deadhead]

Originally Posted by AROWHED

He did offer to take back anything that does not work.

That could be a winner. If you could try them on a head at Norwalk or something to see if they mated up, that would save some shipping madness.

[Engine-Ear]

Flange bolt patterns are (or SHOULD be) the same...the exhaust port plane relative to the street may not be.

[AROWHED]

I'm not sure exhaust flange plane angle will apply, since the Mad Dog's round exhaust port headers are designed for RAIV heads that never existed prior to 68(?). In short, the headers are custom units to put a hi-performance engine into the older body.

[RAM YAK II]

I was in Mad Dogs shop to pick up headers for my '62 Cat a few years back and he was jigging-up headers for a Bronco. He said he makes custom headers for many one-off apps. as well. Back in 1963 I built my own headers for my then owned '62 and I am just grateful he makes them for guys like me that are too busy and too old to DIY. Maaaaaybe he'll make you a custom set, Ken.

Doug...

[AROWHED]

Ram Yak..would you happen to have some pics of those headers? Are they the ones with 2" primaries?

[monsterflake]

i had 3-tube, 2nd gen firebird headers on the 400/400 turbo in my '64. i'd guess that a used (cheap) set would be worth the investment, at least to try out.

[AROWHED]

Got to look at a fellow PYer's 64 Cat, which also has headers but of unknown manufacturer. Seems to me 64 and 65 are nearly identical as far as any interferences there may be for header fit. Gonna roll the dice and order the 2" primary part number for a 64, and hope they will slide right into my 65. The one thing I did notice that may be a problem is his engine sat about 1" higher, as measured from the center exhaust port edge, down to the steering gearbox.

[Deadhead]

It looks like there is some room to play with. Remember, you may need the angled oil filter adapter. If that is your only interference you could be gold.

[AROWHED]

I do have the angled filter adapter required for long branches, which is whats in the car with a D-port 455 now. However, a note Mad Dog has on his site for the 61-64 header is that a remote oil filter is required. Glad I picked up at Norwalk one of those oil line adapter plates that bolts in place of the filter housing...saves the hassle of having to thread the oil passageway holes in the block.

[66bonne]

Mike-very anxious to hear if the 2" primaries fit. With your ingenuity I bet that you can get them in there.

Jim