Scoop, hood, carb sealing

[BelvedereII]

I've just bought a hood scoop from Kramer Automotive to install on my '67 Belvedere II, and was wondering how any of you have sealed your carbs to the hole in the hood. I'm imagining a fabbed plate around the carb flange which will seal the base of the filter, and outboard of that will be a foam seal of some kind to keep the hot air out and the incoming cooler air heading toward the filter. How much wiggle room have you found to be necessary? I'm thinking the carb flange plate should rise to within an inch or so of the hood surface to minimize the foam required, but have seen images of original factory hoods that have a plate on the hood itself instead of at the carb. Appreciate any help!

B2

[cudabob496]

To check hood clearance, roll up a ball of playdough, put it on top of your aircleaner, then close the hood. Open hood, and measure thickness of playdough, which maintains the shape after being squished. Allowed me to use a single plane and eventually have 1/4 inch hood clearance, after machining a little off the top of the intake.

[cudabob496]

I have one of these ram air boxes on my Cuda. Good for 25 horsepower. Cold air at a higher pressure to the carb.


http://ramairbox.com/index.html

[4HUNTIN]

Hello, I took the measurements from the carb center.
Took them to the local heating shop, and he made me one out
of sheet metal for $20.00.
He rolled the ends up and bead rolled it for strength.
I cut the hole for the carb.
It fits under the filter base , and in my car 2 inch foam for sealing
is all that holds it in place.
It pick my car up at least a tenth and stays put at 119.58 mph.
Steve.

[kick_the_reverb]

Do you have any pictures of it?
Thanks,
Ran

[BelvedereII]

CB496, that's what I did to check clearances with the 360 and now the 440 to the stock hood. Nobody's asked yet why I have playdoh in my tool cart, but I'm ready with that answer. My manifold's a Holley Street Dominator and with a drop-base air cleaner I've not had any problems, even have more than 1/2" clearance with a 14x3" filter. I had planned on getting a ram air box for my car, and one of the guys at the track has a homemade version with dryer duct under the bumper, but since the hood scoop is correct for the year/model of my car I'm going to go this way.

4huntin, that's what I think I'll be doing, going to the HVAC shop in town and seeing what they can do. It seems as long as the base is flat where the filter sits on it, it will seal that side and the cleaner's top plate will secure the top, the wing nut holding everything pretty solid. I would imagine the new base should extend a couple of inches beyond the filter to let the air flow around it, then insulating foam should rise to the hood bottom. That will make for a pretty big assembly, so maybe the filter should be less than the 14" I have now. In fact, maybe a top-plate filter like the K&N XTREME should be used to get air in directly from the top. Since I'll have to go from the drop-style air cleaner to a higher one, I'll need to have the hole through the hood large enough for the filter to stick up. I've got a bunch of thin metal and fiber spacers plus a 3/4" or 1" plastic spacer for my TQ so I have a little leeway with the final dimensions.

In some of the more serious scoop setups the hole through the hood under the scoop is pretty small, as the air is being forced on the faster cars they probably don't need much. I'm just trying to get outside air into the carb and looking for more consistency in bracket racing.

Ran, I don't have any pictures yet but will take some and post them when I can. The scoop came painted white, and I'm going to try to match the paint to the car's original gold. I hate to hack up my original hood, but if I can find a replacement I'll probably just paint it and the scoop gray or black. A mis-matched scoop color is one thing, trying to paint a scoop AND hood to match the rest of the car doesn't seem very likely to turn out well!

B2

[BelvedereII]

Here are pics of the hood, the first is the approximate positioning on the hood, the second shows the reinforcement they've put into the top of the scoop, and the third shows the kind of minor work I'll have to do to smooth everything out for paint.

As Mrs. Kramer told me when I picked up the scoop, these last ones they've had were flawed from the manufacturer and will require some sanding. They discounted them $50, which was nice. The mounting tabs are recessed slightly and Kramer's sell a kit of 12 bolts and clip-type nuts for mounting from under the hood. You might be able to find them locally for less at a hardware store than Kramer's charges, it's up to you.

The factory scoops were pretty lame, as they slapped together enough to make the minimum number of cars and weren't very precise. No surprise when you consider the minimal production numbers. Kramer's also has a set of pictures of an original WO23 hood showing the mounting of the scoop and the dimensions of the hole, with the scoop removed. Interesting and very chop-shop looking. Again, if you've been around Chryslers for more than a month it all makes sense.

B2

[cudabob496]

Looks awesome! As far as "CB496, that's what I did to check clearances with the 360 and now the 440 to the stock hood. Nobody's asked yet why I have playdoh in my tool cart, but I'm ready with that answer." just tell them those darn kids are playing with your tools again!

[kick_the_reverb]

Sorry BelvedereII, I should have made myself more clear...I meant to ask if 4Huntin has pics...that might help you or others.

Ran

[4HUNTIN]

Hard to get a good pic.
Hope its not to large a file.
Pretty crude but it picked my car up.
Thanks Steve
Sorry file is 20 kbs too big.

[sthorvictor75duster]

by the way how much power can oyu usually get from a ram air system?? and would a duster scoop work at all or are the openings too small???

[cudabob496]

Originally Posted by sthorvictor75duster

by the way how much power can oyu usually get from a ram air system?? and would a duster scoop work at all or are the openings too small???

I have a ram air box. You get a 1% power increase for every 10 degrees you lower the air temp to your carb. So on my 600 hp 496, if I suck in 50 degree cooler air than what is in the engine bay, thats a 5% power increase, or 30 hp. Given the ram air box setup may cost 150 bucks, its one of the best bang for the buck addons.

http://ramairbox.com/index.html

[sthorvictor75duster]

ok, now is there any way i can use the scoop i have on my duster, and make a ram air system??

[MOPEkid]

How would someone go about getting a system hooked up to plumb cold air from the A-body type dual scoops to the carb/air cleaner, and making it possible to switch to warm underhood air in case of rain?

[cudabob496]

Originally Posted by MOPEkid

How would someone go about getting a system hooked up to plumb cold air from the A-body type dual scoops to the carb/air cleaner, and making it possible to switch to warm underhood air in case of rain?

Anything is possible. You just have to get creative. Some systems use baffles and drains so the water can't get to the carb. On my ram air system, the air scoops are low in the grill, so the water from rain can't move up hill to the carb. Plus I don't drive in the rain if possible. Maybe you're better off having your existing scoops for looks, and putting in a ram air system for about $150, with the scoops low so rain won't get to the carb.

[sthorvictor75duster]

ok so is there any way i can use the scoop i have to make a box of sorts or get one???

[MOPEkid]

What materials would I use to mock it up and then make the actual system? I don't have any scoops right now, but I want to put some on a fiberglass hood when I repaint my car.

[cudabob496]

well, guys, seems you may want to do something like 4HUNTIN did on the previous page. You need a scoop on the top of the hood, with a hole in the hood under the scoop, then you need to create some type of metal pan around the carb that can make a seal under the hood using some foam. Seems like it would be easier to just get a ram air box that is already designed to enclose the airfilter and direct cold air from the front of the car to the carburator. And, you can still keep the hood scoop on the top of the hood for looks.

[OHD]

On one of the 66 Bels we are working on, on the top of a Hogans tunnel ram we used a carbon fiber/aluminum dragster pan attached to the twin Dominator bases, sealed it with a foam kit around the front and sides to the seal on the bottom of the reinforced scoop and draw cold air from the cowl area vrs the warmer air of the engine compartment. The dense foam is attached to the scoop base front & sides and seals to the bottom of the scoop.

The cowl area opening was reduced in size and reinforced, to increase and direct air flow, by using a snorkle scoop front (neatly cutt off from a Harwood scoop), inverted, and matted into the opening. Then the opening was screened to eliminate any "critters" from being forced or sucked into the carb breathing area.

When the hood is closed, all is tucked neatly under the fibergalss hood/cowl scooped system, that looks and functions.

When the engine is not running, we seal it all, with the Hardwwod scoop plug, inserted into the opening to protect everything.

On the other Bel l we are installing a C&S drop base system complete, under the stock type modified and reinforced scoop, installed on a fiberglass hood, to top off a polished single dominator RR3 system.

We have a "Dart type pro scoop" we reinforced with additional layers of fiberglass matte, to make solid, flat, and not flex, we are not using if someone needs it. It was too short to cover up the tunnel ram.

[BelvedereII]

Got it completed, and it appears to work pretty well.

Bought a hood off of a '66 Belvedere so I didn't have to cut mine. Found the center point of the carb stud and drilled there for reference. It's offset just over 1" from center. Cut a 16" hole for a 14" cleaner, located the scoop where I wanted it and drilled mounting holes. Had to cut away a little in the underhood bracing in places to gain access for bolts. This all left a gap of about 1.5" height at the back where incoming air can escape through underhood bracing "ductwork" and blow down into engine compartment. The foam on the carb plate seals to hood at the front, and to the bracing at the back to make this happen. You can see it in the picture. The hood was blue and I figured they'd never match my faded gold paint on the car so I took the hood and scoop to a local shop to have it painted black.

Bought a sheet of 20ga metal about 2'x2' from a local shop. Cut a 19" disc out of that. Bought an air cleaner from a Dodge van at the junkyard. Cut the neck portion out of that, and cut a corresponding hole in the sheet metal disc to fit.

For attaching I would have liked welding but have even less skill there than most other areas, so I just drilled and riveted the carb neck ring to the sheet metal. Bent the outer edge of the sheet metal to gain a little rigidity, and this was a real hack job as I merely used body shaping hammers and an anvil.

The whole thing bolted together pretty well, but just to make sure and add a little more rigidity I cut the bottom ring off another cleaner I had lying around and riveted that in place. This locates the bottom of the filter a little better, although the K&N Xstream filter top locks it in pretty snugly from above.

I bought a Moroso foam replacement piece from JEG's, it's about 4" tall and 1.5" wide and did the measurements with the scoop off. Just placed the new base on the carb, closed the hood and measured the clearance at points of the clock all the way around. Transferred that to the foam and cut. Foam was attached to itself and the base with 3M Superweatherstrip adhesive.

To seal the scoop to the hood, I bought a roll of weatherstrip tape with sticky on one side from the local truck topper shop. I laid the scoop on its top and just ran the tape along the outer edge, 3 pieces cut to length. I didn't bother to trim the inner edges, just cut at each mounting bolt hole and set it in place on the hood. It all bolted right up.

Took my trim strip off of the original hood and mounted it, and when I'd cleaned up the "new" hood I pulled the letters for cleaning and paint. IF ANYBODY HAS A GOOD SOURCE FOR THE BARREL NUTS (or whatever they're called) WITH ATTACHED RUBBER SEALS, please let me know! I found a few sizes at a local bolt/nut/fastener shop but nothing small enough for the PLYMOUTH letters. I may wind up just using the originals and some silicone to seal them.

Hood $150
Scoop around $275 with bolt kit (but I did pick it up)
Junkyard carb cleaner for neck $15
Paint work was $175, a pretty good deal I thought
20ga 2'x2' sheet metal was $5 from local metal shop (would have been $30 at Menards)
I already had the 14" filter and old cleaner assembly for parts
New Xstream filter top and Moroso replacement foam from JEG's was near $80

The carb base is a bit of a Frankenstein piece, but it works. A trip around town and on the hiway yesterday got a couple of angry bugs trapped between the filter and foam, and it's only early spring...can't wait to see what we catch in a summer evening.