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Discussion Starter #1 (Edited)
Ok, so I've got all the parts and will be installing a factory ram air system on my 69 GTO.

I'm running an SD-455 Qjet on this car, and the carb bowl vent is creating a clearance problem with the lower ram air pan. The way I see it, I've got two likely solutions:
1) Use a 3/4" air cleaner spacer to raise the lower pan enough to clear the vent.
2) "Modify" the lower pan to create clearance for the bowl vent.

Of the two options, I like "1)" the best but what I don't know is how this would affect clearance between the lower pan and the hood pan. Would raising the lower pan 3/4" compress the foam pan seal "too much" or otherwise create a clearance problem between the lower and upper pan?

I'm looking for someone who has a factory ram air already in place on their 69 who might be able to give me a little guidance here, if you don't mind.

Thanks,

Bear
 

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Option 1 sounds more reasonable to me. The foam seal will compress more if you raise the pan. I have seen alterations to the foam seal where people have shaved them down 1/2"-a full inch, and they arent really any noticable differences from a stock look. By doing this you are able to leave the air pan and carb intact without any permanent modifications. Also It is easier an cheaper to buy a new foam piece that is just for shows rather than a hacked air pan.
 

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Discussion Starter #3
Option 1 sounds more reasonable to me. The foam seal will compress more if you raise the pan. I have seen alterations to the foam seal where people have shaved them down 1/2"-a full inch, and they arent really any noticable differences from a stock look. By doing this you are able to leave the air pan and carb intact without any permanent modifications. Also It is easier an cheaper to buy a new foam piece that is just for shows rather than a hacked air pan.
I'd prefer to do that, if it will fit. I posted the same query on another forum and was told that raising the pan 3/4" (and therefore, also the air cleaner) will create an interference problem between the air cleaner and the upper pan.

Comments?

Bear
 

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You could run a shorter filter to compensate, but that could choke off the motor. Run a shorter filter with one of them K&N filter tops to make up the difference. :D.
 

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Discussion Starter #5
You could run a shorter filter to compensate, but that could choke off the motor. Run a shorter filter with one of them K&N filter tops to make up the difference. :D.
That's a good idea too. I wonder if the hood pan will clear the bottom pan if I do that?

Bear
 

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This isn't related Bear but .....

Once you have it all done up...
If you leave the hood down all the time the foam will compress and "mush." I see it all the time at shows....

I keep my hood up when the car is parked this keeps the foam looking new and non conformed. Some really look awful I seen.

Just a hint to keep it looking new once its finished up.
 

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^ Wow, that right there is a dedicated RA owner. Pretty slick Judge.

BTW Bear, I just saw on Hot Rod TV that ( I believe ) K&N will custom make filters to any dimension, although I'm sure it could get pricey for something exotic there are so many sizes available I'm sure you could find the right one.

If you need to check for clearance you could use the ol' clay method, mock up your RA setup without the spacer or air cleaner, pile some clay on top in a mound aproximately the height of your setup should be where you think the highest spot would be and shut the hood to see if there is contact.

Do you have the complete setup, with cables and everything? Ram Air is really a pretty cool setup from the factory, I really love that and if my setup were more "stockish" I'd have to install some sort of exhaust cutout like the VOE right next to it.
 

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Is your lower pan an original factory piece or a repo? If it is a repo, I would cut and modify it to keep it at stock height. ALOT less headaches, trust me!! I put a performer RPM manifold on 69 Goat, it is about 3/4" taller than stock. I used the lower Ram Air pan with the foam at the stock height, it looked like crap when the hood was open, and I had to really push down to get the hood to close. It also pushed up on the rear of the hood, if your hood hinges have any slop at all, this will show you and everyone else!! I ended up cutting the foam down by 3/4" and the glued the cut side to the pan, so the nice machine cut side is up. For the air cleaner/filter, 2" is too tall and WILL hit the upper pan, anything smaller will be too short and will choke the carb. I am not going to tell how I fixed that issue unless you ask, MANY purists will cringe when they hear what I did!!

I did run one of the K&N filter tops. I don't care how well the Ram Air setup is built and installed, They are NOT watertight, even with the flappers closed tight. So all of the water that gets past the scoops when it rains or when you wash the car goes right through the filter top and into your engine!! Trust me, I know, don't use one with RA!
 

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Discussion Starter #9
Is your lower pan an original factory piece or a repo? If it is a repo, I would cut and modify it to keep it at stock height. ALOT less headaches, trust me!! I put a performer RPM manifold on 69 Goat, it is about 3/4" taller than stock. I used the lower Ram Air pan with the foam at the stock height, it looked like crap when the hood was open, and I had to really push down to get the hood to close. It also pushed up on the rear of the hood, if your hood hinges have any slop at all, this will show you and everyone else!! I ended up cutting the foam down by 3/4" and the glued the cut side to the pan, so the nice machine cut side is up. For the air cleaner/filter, 2" is too tall and WILL hit the upper pan, anything smaller will be too short and will choke the carb. I am not going to tell how I fixed that issue unless you ask, MANY purists will cringe when they hear what I did!!

I did run one of the K&N filter tops. I don't care how well the Ram Air setup is built and installed, They are NOT watertight, even with the flappers closed tight. So all of the water that gets past the scoops when it rains or when you wash the car goes right through the filter top and into your engine!! Trust me, I know, don't use one with RA!
As it turns out, the lower pan is the only piece I have that's a real factory part. I've been sitting on it for years. All the other ram air components are repro pieces that I just bought. That's really good information about the clearance and the water leakage though, I hadn't thought of the water issue. Even though it's a real pan, that pretty much clinches it for me that I'm going to modify it to clear the carb vent instead of trying to raise the pan. I suppose I -could- run my original 69 Qjet and avoid all the problems, but I'd be giving up 50 cfm of air flow from the SD carb, and my 461 really needs the air. It could probably use more than even the SD carb provides, in fact.

Bear
 

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The vent mod will be under the air cleaner lid right? If so, then nobody will see it. I don't know how big a "bump" you have to make to clear the vent, or the size of the vent, might I suggest a bb gun co2 cylinder. Empty it and then cut the round end long enough to fit over the vent, make a 3/4" hole in the pan to fit it, then weld it in and paint. If you are careful and weld from the bottom, with a little filler around the top of the pan, it will look like part of the stamping with the air cleaner lid off. We did that to a set of DeSoto Hemi valve covers to clear adjustable pushrods, saving around $350. That is the way I would go. I am using an Edelbrock 750 carb, it fits with the only mod being a banjo fitting for the fuel inlet.
 

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This isn't related Bear but .....

Once you have it all done up...
If you leave the hood down all the time the foam will compress and "mush." I see it all the time at shows....

I keep my hood up when the car is parked this keeps the foam looking new and non conformed. Some really look awful I seen.

Just a hint to keep it looking new once its finished up.
I do the same after every drive before I tuck her in.
 

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Discussion Starter #12
The vent mod will be under the air cleaner lid right? If so, then nobody will see it. I don't know how big a "bump" you have to make to clear the vent, or the size of the vent, might I suggest a bb gun co2 cylinder. Empty it and then cut the round end long enough to fit over the vent, make a 3/4" hole in the pan to fit it, then weld it in and paint. If you are careful and weld from the bottom, with a little filler around the top of the pan, it will look like part of the stamping with the air cleaner lid off. We did that to a set of DeSoto Hemi valve covers to clear adjustable pushrods, saving around $350. That is the way I would go. I am using an Edelbrock 750 carb, it fits with the only mod being a banjo fitting for the fuel inlet.
I like that idea too. One other suggestion was to cut a precise hole in the bottom pan and rim it with an o-ring such that it fits tight around the bowl vent. That way the vent would be getting filtered air --- but then also it would be 'seeing' partial vacuum due to intake air flow too and I'm not sure how I feel about that. I've even got some empty CO2 cartridges laying around ---- thanks for the tip!

Bear
 

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Discussion Starter #13
... might I suggest a bb gun co2 cylinder. Empty it and then cut the round end long enough to fit over the vent, make a 3/4" hole in the pan to fit it, then weld it in and paint...
69Goatee, I owe you a "frosty beverage". :cheers

Today I cut a hole and welded in the end of a CO2 cartridge, just tall enough to clear the vent. It's perfect. Once I get it primed and painted, it'll look like it grew that way....

Thanks!

Bear
 

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I love it when a plan comes together! I will be enjoying a "frosty beverage" tonight in my shop while running fuel line on the GOAT!:cheers
 
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