Looking for alternative ram air plenum seal

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The stock seal is quite high at 1"+. I believe we can find an alternative seal or profile that will fit but with less height - and probably at a lower cost. This will help on gaining space for a carb spacer or whatever. I am currently running a Blue Thunder manifold with a 1/4" spacer and after modifying the plenum I am still pushing the hood up quite a bit. The hood closes but I know I am placing a lot of pressure on the seal and ram air hood attachment. I looked around but I can't find a good rubber profile that will fit. It doesn't need to be a whole circle since a straight one could be glued. Any ideas from anyone?
An option could be a D profile section glued to the plenum lip. Maybe cutting the bottom of the D so it fits under the air plenum's seal lip.
 
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There are also a lot of different shapes available on Amazon. Here is an example:
Thanks. Yes, there are a few that I it narrowed down to but I was hoping someone has tried one that worked. Otherwise I will have to do trial and error.
I like this one: https://www.amazon.com/gp/product/B00NL4AATS/ref=ox_sc_act_title_1?smid=A339EJ58RW9U9H&th=1
EPDM should hold well to underhood temps.
 
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I wonder what's the diameter of this one. It would be nice for it to be of larger diameter.
Along the same idea, there is a 1"x1" one in Amazon:
 
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You mean gap from the metal of the air cleaner to the hood? I would think that 1/2" would be sufficient, not sure about a 1/4", I don't know how much deflection the motor mounts would have. You should be able to check by using some playdough on the air cleaner, closing the hood and accelerating the engine in neutral against the brake and the see how much it deformed.
 

Sheriff41

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roll up some aluminum foil, place it on your air cleaner housing, close the hood, open the hood and measure the squashed foil. That should give you an idea what the compressed space you need to address.
 
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roll up some aluminum foil, place it on your air cleaner housing, close the hood, open the hood and measure the squashed foil. That should give you an idea what the compressed space you need to address.
I have done that a few times. I was just trying to account for engine movement during a hard launch. I guess I will have to do the foil trick and then take it out for a spirited drive.
 

machphil

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You mean gap from the metal of the air cleaner to the hood? I would think that 1/2" would be sufficient, not sure about a 1/4", I don't know how much deflection the motor mounts would have. You should be able to check by using some playdough on the air cleaner, closing the hood and accelerating the engine in neutral against the brake and the see how much it deformed.
Acceleration without load is not going to transmit the torque of the engine through the motor mounts as much as actually having it in gear and the engine actually working against the weight of the car. Or, you could put a tire between your front bumper and a tree and try to push the tree over.😁 That would rock the engine on the mounts. Bottom line, torque is not exhibited in any real world display unless you have a load on the crank that forces the block to ROCK!;)
 
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Acceleration without load is not going to transmit the torque of the engine through the motor mounts as much as actually having it in gear and the engine actually working against the weight of the car. Or, you could put a tire between your front bumper and a tree and try to push the tree over.😁 That would rock the engine on the mounts. Bottom line, torque is not exhibited in any real world display unless you have a load on the crank that forces the block to ROCK!;)
I see what I did, I put accelerating the engine in NEUTRAL against the brake, which makes no sense :) I meant accelerating the engine in gear against the brake...
 
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I think this is a good candidate:

The channel at the bottom may even fit in the air plenum.
I bought this seal and you are not going to believe how well it fits. The U channel part snaps perfectly in the lip of the plenum and sticks up 3/4". Compared to the stock it's about 1 1/4" lower. Right know i estimate i am compressing the seal about 1/4" which I think is perfect.
And for bonus, it is a lot cheaper.
 

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