Replace 96 doorman manifold with...
- Thread starter GRWeldon
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- 1997 Thunderbird 4.6, 1998 Mark VIII LSC
Assuming it's the original with the aluminum crossover, and it's in good condition (check for cracking in the composite parts under the crossover), you'd have to follow the original PI manifold upgrade conversion instructions.
Basically, you need the PI valley heater tube and nipple, PI manifold gaskets, and some RTV to patch the coolant passageway where the shape changed (basically use the gasket as a guide to ensure it seals). You lose a couple ft-lb of low-end torque, but the engine breathes way better above 3500-4000 and typically 10-12 HP is added.
Basically, you need the PI valley heater tube and nipple, PI manifold gaskets, and some RTV to patch the coolant passageway where the shape changed (basically use the gasket as a guide to ensure it seals). You lose a couple ft-lb of low-end torque, but the engine breathes way better above 3500-4000 and typically 10-12 HP is added.
Grog6
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This is a nice upgrade, just let the rtv dry overnight.
Generalee0527
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You can also just use heater hose under the intake and assemble a couple nylon elbows/couplings and such to connect heater lines. It will have to route along the left side(drivers side) a little off the valley but under the runners.
This is the best (only?) video I've seen on the swap. It walks you through everything you need to do. I think he was on the old board. I don't know if he is over here. Just click on the link to watch in on YouTube's site.
Grog6
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heaterhose dies pretty quickly in the valley; that is why ford went to a hard line.
After watching the video, I think the best course of action would be to scrounge some PI heads and do the whole 9 yards. Especially since the car needs valve seals anyway. I'll put it on the list, which means it probably won't get done. Thanks everybody for the input!
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On a 96 you could just put PI cams in and get the same power as a PI motor paired with the intake. PI heads don’t actually flow meaningfully better than 96+ npis, all you gain from a headswap is the extra point in compression and about 10 horsepower, but you also need to run premium gas. PI heads should also be tuned as the combustion chamber changes enough where imthey don’t want as much spark advance as even the stock npi head tune has.
