Packard Forum Index » Modification Discussion

Let the ride decide Quote:

I believe that the headers can be installed from below, so there is no issue with any part of the steering. In other words, the steering would stay in place. The exhaust manifolds, starter/solenoid and head pipes would be removed for installation, but not the steering.

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For ease of installation, each side will probably be two sections connected with a flange connector probably right behind the engine where the 3 pipes come together.

The headers are not going to weigh much more than the cast iron exhaust manifolds, so there should be no weight/stress issues.

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The only real downside is that you will lose the thermocoil valve between the driver side exhaust manifold outlet and its head pipe. Except in Winter, if you even drive your Packard then, cold start up will take longer to warm the intake manifold without this valve. This is a normal deal when using headers. Initial start when cold will not be affected as this is mostly determined by the carb choke.

The upside for the engine is one of efficiency on the exhaust cycle as it is with any improved exhaust system. This translates to more torque and HP and maybe even a little better gas mileage. Full throttle peak power should go up at least 25HP.

You could use the existing dual exhaust system, if so equipped (most are). Upgrading to high performance mufflers will add even more efficiency (power). That's up to you.

Craig

cli55er Quote:

Hank, PM me with the cam specs and I'll put it through my engine simulation software filtered by my experience.

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I've seen header installs with and without a starter heat shield. Under normal driving conditions, the exhaust is not that hot. Under load, it is hot, of course. FWIW, I'm not going to put a heat shield on my Panther.

If the starter gives you problems when hot, then by all means try a heat shield first thing.

Craig

i didn't plan on using the coil valve anyways.

PM sent with specs, if you need any more info then that on the CAM i'll have to get Jack involved.

i personally plan to go with some hi-po mufflers, like magnaflow.

Hank

HH56Quote:

Howard,

After viewing and measuring the gearshift linkage my 55 Pat, I don't think the headers will interfere. But, I'll have to change the routing a little in that area. I'm going to wait until I do the metal prototype. Since the pipes and collector are smaller than the mockup, it'll help the situation. I'll also mockup the linkage and cross-shaft to make sure. Thanks for pointing this out.

Craig

Good progress on the mockup of the Passenger side the last two days, although the #2 cylinder outlet was a bit of challenge. I'll post digipix of the finished mockup probably tomorrow.

Craig

Didn't quite get the P-side header mockup completed today.

I had a female friend roar up in her Yamaha V-Twin in her leathers which kind of distracted us on the last part of our work. Oh yeah, she's also a big rig truck driver after being an engineer before. She also helped out on my 1963 Tempest Ram Air III and my 1979 Trans Am W72/WS6 4-speed. So one can understand why we didn't quite get everything done.

We had to knock down a couple of shots too, so that even further delayed getting stuff done. LOL!

Maybe tomorrow.

Craig

As promised, the completed mockup of the passenger side headers.

Clearance between motor mount and #2 pipe:


Clearance between upper rear A-arm and #2 pipe:


Clearance between road draft tube and #8 pipe:


Completed passenger side view:


Completed passenger side rear view from left:


When comparing the driver side with the passenger side, notice that the #1 tube is routed above #3/#5 outlet in order to clear the steering gear box. The #2 tube is routed under #4/#6 outlet in order to clear the generator. The #8 tube was also a challenge in clearing the road draft tube.

Craig

couple things of notice.

the draft tube isn't secured to side of where the bell housing connects.

also i don't see trans cooler lines mounted.

Hank

cli55er Quote:

I believe that the road draft tube is very close to the correct position. A good point on the trans cooler lines, but I don't have a spare T-U to mount in the mockup chassis. A closer check on both will have to wait until the metal prototype is done and fitment on my 55 Clipper Super, which is complete and stock. I've decided to use the Clipper rather than my 55 Pat, which as you know has some modifications. My 56 400 does not have a road draft tube because it was removed in 1964(?) to fit a PCV system for California smog compliance.

Craig

is the tang on the draft tube connected to the bolt on the engine? if so i stand corrected, but i believe it should be closer to the motor. i'll have to look at mine again.

the trans cooler lines....man those will be a tough one with the way the pipes are going. might have to reroute the cooler lines.

Hank