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Weiand 7503 (Poly 318)

earlymopar

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For those of you who have used this manifold, I'm interested in what the rear port shown was provided for.

Thanks, EM
 

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No photo, but I'm guessing you're referring to the threaded port on the back, which is a vacuum port for the brake booster. just plug it if not needed.
upload_2019-4-30_6-25-6.png
 
every time i see one of these intakes,i start thinking about getting 1 for my poly.
i know its just a 318,but i cant help myself.
 
No photo, but I'm guessing you're referring to the threaded port on the back, which is a vacuum port for the brake booster. just plug it if not needed.View attachment 758537


Strange that my picture file dropped from the post. I just reattached it. Yes that's the port. I already had it blocked but was just interested in what the provision was for. Actually, my manifold has all indications it's a one of the first castings or possibly an even earlier prototype in that it had / has none of the production markings cast-in. It is simply stamped "7503" on the bottom of the manifold. The casting quality is also not quite up to the same finish level as the production castings with cast-in graphics. It was in such rough shape that it was perfect for modifying into the supercharger manifold it is now.

- EM
 
IMG_0819.jpg
Best thing I ever did to my Poly. Intake,carb and dual exhaust.
 
Poly with Magnuson.jpg


This is mine before I swapped out the P600 manifold shown to the 7503 Weiand in order to reduce the overall height. Shown on the P600 is a 3-deuce to single-4plenum I made to allow the Magnuson to be added but also to create space for an intercooler if needed. The same plenum allows a single-4 barrel (without the supercharger) by changing out the top plate). The engine shown is actually my "test mule" and has 105k miles on it. I have a fresh engine I'll drop in this winter. I'm just buttoning-up things now with the test-mule and have it mated to a new TKO-600 5-speed. The headers are 302-351 Ford stainless steel. This is all in my 65 D100 Utiline.

- EM
 
I posted this photo of a friends Poly before.Stroked to a 390 and heads by Toth Performance. It's in a 64 Dodge wagon and it will give any big block a run for the money.I couldn't get over how this thing screams when he let me drive it.
IMG_2722.jpg
IMG_2724.jpg
 
View attachment 758710

This is mine before I swapped out the P600 manifold shown to the 7503 Weiand in order to reduce the overall height. Shown on the P600 is a 3-deuce to single-4plenum I made to allow the Magnuson to be added but also to create space for an intercooler if needed. The same plenum allows a single-4 barrel (without the supercharger) by changing out the top plate). The engine shown is actually my "test mule" and has 105k miles on it. I have a fresh engine I'll drop in this winter. I'm just buttoning-up things now with the test-mule and have it mated to a new TKO-600 5-speed. The headers are 302-351 Ford stainless steel. This is all in my 65 D100 Utiline.

- EM
Oh wow-not grampa's 318 or pa's! Mine was redone with a hotter cam, solid lifters, eddy 4bbl headers, 3" etc. While it has nice giddy up not much as I was hoping for so still on the hunt for the mystery slug...
 
...It was in such rough shape that it was perfect for modifying into the supercharger manifold it is now.
- EM
It does look like an early one, but I don't think it's a 'first run'... I have seen a few older ones, and yours isn't too far off from what mine was, which was purchased from Summit a decade or so ago. The really early ones didn't have the "W" outline.. they were like the one below:
002.jpg

With regards to being a blower manifold... Dick Landy used to sell Blower Kits for the Poly, he put together a 144 blower and a 174 blower kit (Holley) and he shaved the top off of the 7503 and welded a blower plate to it. If I can recall, the kits were $4500 and $5500, and would produce in the neighborhood of 350HP and 450HP, respectively. That was a long time ago, and I had never seen one of his kits... not for lack of trying!
 
It does look like an early one, but I don't think it's a 'first run'... I have seen a few older ones, and yours isn't too far off from what mine was, which was purchased from Summit a decade or so ago. The really early ones didn't have the "W" outline.. they were like the one below:
View attachment 758998
With regards to being a blower manifold... Dick Landy used to sell Blower Kits for the Poly, he put together a 144 blower and a 174 blower kit (Holley) and he shaved the top off of the 7503 and welded a blower plate to it. If I can recall, the kits were $4500 and $5500, and would produce in the neighborhood of 350HP and 450HP, respectively. That was a long time ago, and I had never seen one of his kits... not for lack of trying!


Yes, I'm aware of the Landy kits that were produced. I've often wondered how many were actually made and sold. I suspect very few.

The manifold shown is not mine but is simply a picture I borrowed from the internet. Mine doesn't even have the Weiand script or the 7503. There was only "7503" hand-stamped into the underside of the manifold. There is nothing on the top surfaces. As well the casting surface finish of mine is / was like none others I've seen. It was very wavy and rough. I also found major casting voids in at least 2 of the mounting holes indicating metal flow was not correct or certainly not yet optimized. Mine does not have the 2 small holes shown in this picture at the 1:00 and 7:00 positions relative to the carburetor flange or the hole in the stiffening rib shown in the upper-left in this picture. The temperature sender hole on mine also looks nothing like the one in this picture.

- EM
 
Yes, I'm aware of the Landy kits that were produced. I've often wondered how many were actually made and sold. I suspect very few.

The manifold shown is not mine but is simply a picture I borrowed from the internet. Mine doesn't even have the Weiand script or the 7503. There was only "7503" hand-stamped into the underside of the manifold. There is nothing on the top surfaces. As well the casting surface finish of mine is / was like none others I've seen. It was very wavy and rough. I also found major casting voids in at least 2 of the mounting holes indicating metal flow was not correct or certainly not yet optimized. Mine does not have the 2 small holes shown in this picture at the 1:00 and 7:00 positions relative to the carburetor flange or the hole in the stiffening rib shown in the upper-left in this picture. The temperature sender hole on mine also looks nothing like the one in this picture.

- EM
ah.. okay, I thought you were showing your intake. Yes, sounds like you have one of the very earliest. I had talked to Landy's son for a couple of weeks back in the 1990s trying to get pictures or information about their blower kits. He had given me specs, but couldn't find any pictures or provide contacts. I thought it was pretty cool that his kits were a direct bolt on - perfect for the Poly because they're like 8.8 CR or something like that.
 
Incidentally, I still have this intake in primo condition. Not sure what I'm going to do with it at this point, but if I can find another car like a 55 Savoy or something, I'd entertain rebuilding the Poly and running my dual quad EFI again.
wieanddq.jpg

dualquadefi-640x425.jpg
 
ah.. okay, I thought you were showing your intake. Yes, sounds like you have one of the very earliest. I had talked to Landy's son for a couple of weeks back in the 1990s trying to get pictures or information about their blower kits. He had given me specs, but couldn't find any pictures or provide contacts. I thought it was pretty cool that his kits were a direct bolt on - perfect for the Poly because they're like 8.8 CR or something like that.

No kidding. That would have been a far easier route for me. I've had to make all of my pieces or adapt. I left my new engine @ a +.030" 318 and have NOS TRW forged pistons and am right @ 8.0 CR. Camshaft is 224/224 @ 050”, 270/270 adv, .470”/.470” lift, 112 lobe separation. I added 1.94” / 1.60” Pro-Flo Stainless Valves after machining the bowls. I'm figuring normally aspirated this should easily be in the 350 HP range with headers and 4 barrel. The supercharger should add another 100 HP conservatively. Fun stuff.

- EM
 
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