How many here are running the Weiand 7503 on their Poly's?

[toolmanmike]

I got a nice 7503 with my Polara and because of my fuel/carb issues lately, I'm seriously thinking about installing it along with an Edelbrock 650 AVS II carb which I also have.
How does your combination work?
Any loss of bottom end because it's an open plenum intake?
Are there any crazy things you have to change as far as brackets or hook ups to make it work?

I would think a 4 barrel, dual exhaust, and electronic ignition, would be a nice addition to a stock Poly.

 

[Mr. Mike]

Nice find you got there. To run an AVS you'll need an adapter that will add height and lessen hood clearance.
As with a lot of early parts there is no provision to mount the ignition coil and you'll have to fabricate a throttle cable bracket.
The carb issues due to ethanol gas?
There are rebuild kits with a resistant needle and seat assembly available.
Also if memory serves the was a factory two 4bbl manifold that was 360.

 

[toolmanmike]

Nice find you got there. To run an AVS you'll need an adapter that will add height and lessen hood clearance.
As with a lot of early parts there is no provision to mount the ignition coil and you'll have to fabricate a throttle cable bracket.
The carb issues due to ethanol gas?
There are rebuild kits with a resistant needle and seat assembly available.
Also if memory serves the was a factory two 4bbl manifold that was 360.

Thanks for the response. I haven't mated the carb and intake up yet. I wondered if an adapter or some carving may be necessary especially for the secondary butterflies. I need to search around the site for a nice photo of a stock intake and compare it with the Weiand to see what is different. I didn't think about the coil but that can be mounted pretty much anywhere. The throttle cable bracket may take some modification. I do have a couple of LA brackets that may be an option. Thanks for your input.

 

[LB0442]

Here are some pictures of original ones. One of them I put on a D100 which has throttle linkage rods, no cable. I had to mix and match various linkage/kickdown parts.

 

[Mr. Mike]

Here are some pictures of original ones. One of them I put on a D100 which has throttle linkage rods, no cable. I had to mix and match various linkage/kickdown parts.

View attachment 1862534

View attachment 1862533

I had one of those manifolds on my 1964 Plymouth convertible using a 1967 383 AFB bought from a Chrysler dealership.
The ears were drilled for both mounting bolt patterns, I opened up the secondary hole to clear the throttle blades on the carb.
I can't remember if I did anything to the throttle cable bracket.

 

[toolmanmike]

Here are some pictures of original ones. One of them I put on a D100 which has throttle linkage rods, no cable. I had to mix and match various linkage/kickdown parts.

View attachment 1862534

View attachment 1862533

Thanks for the pics. That will give me something to go by and compare to.

 

[66 Sat]

I had a 7503 on my 318 poly when I bought it. It was a dog on the street with a 3.23 rear and stock converter. Huge torque hole in the bottom end but then took off at 3,000rpm. It would never take full throttle off the line, was quite painful sometimes if you wanted to get into a gap in traffic with that big bog when you hit the throttle, but the throttle response in the upper rev range was excellent. I sold it and bought a factory 4 barrel cast iron manifold instead, which is good from idle to 5,500rpm.

Gary Pavlovich reckons even the factory 2 barrel manifold with a 500 cfm Holley is superior on the street to the 7503.

Unless you have a stroker or a 4.10 rear end I honestly wouldn't recommend the swap.

One thing that's superior to the factory manifolds is the weight. I've spent the past 2 weekends hoisting the 45 lbs cast iron manifold around, porting the manifold and opening up the plenum. Re-installing it, leaning over the front of the car, is not a lot of fun. It's nearly finished, I'll let you know if there's any improvement for what was a lot of work.

 

[Geoff 2]

^^^^^This. Mate put the Weiand single plane intake on his 318. Not much better than the factory 2 bbl.

 

[Polyhead]

I got a nice 7503 with my Polara and because of my fuel/carb issues lately, I'm seriously thinking about installing it along with an Edelbrock 650 AVS II carb which I also have.
How does your combination work?
Any loss of bottom end because it's an open plenum intake?
Are there any crazy things you have to change as far as brackets or hook ups to make it work?

I would think a 4 barrel, dual exhaust, and electronic ignition, would be a nice addition to a stock Poly.

The 7503 is a poor match for a stock or mild 318. It kills torque and part-throttle response under about 3,500 RPM. The intake doesn't necessarily require more displacement, but the area is shines is with larger valves, head porting, and a high-revving cam, lower gearing, and RPM sustained above 3,500. The exception here is that it's a good intake for an EFI conversion.

As 66 Sat mentioned, the factory two-barrel with an adapter and Holley 7448 for a stock 318 or 4412S for a mildly modified 318 will outperform the 7503 on a stock or mild 318. You can find a ton of poly A info on this website Poly 318 Intake Manifolds - Poly318.com

 

[toolmanmike]

I had a 7503 on my 318 poly when I bought it. It was a dog on the street with a 3.23 rear and stock converter. Huge torque hole in the bottom end but then took off at 3,000rpm. It would never take full throttle off the line, was quite painful sometimes if you wanted to get into a gap in traffic with that big bog when you hit the throttle, but the throttle response in the upper rev range was excellent. I sold it and bought a factory 4 barrel cast iron manifold instead, which is good from idle to 5,500rpm.

Gary Pavlovich reckons even the factory 2 barrel manifold with a 500 cfm Holley is superior on the street to the 7503.

Unless you have a stroker or a 4.10 rear end I honestly wouldn't recommend the swap.

One thing that's superior to the factory manifolds is the weight. I've spent the past 2 weekends hoisting the 45 lbs cast iron manifold around, porting the manifold and opening up the plenum. Re-installing it, leaning over the front of the car, is not a lot of fun. It's nearly finished, I'll let you know if there's any improvement for what was a lot of work.

View attachment 1862693View attachment 1862694View attachment 1862696View attachment 1862699

Thanks for all the info.

 

[toolmanmike]

The 7503 is a poor match for a stock or mild 318. It kills torque and part-throttle response under about 3,500 RPM. The intake doesn't necessarily require more displacement, but the area is shines is with larger valves, head porting, and a high-revving cam, lower gearing, and RPM sustained above 3,500. The exception here is that it's a good intake for an EFI conversion.

As 66 Sat mentioned, the factory two-barrel with an adapter and Holley 7448 for a stock 318 or 4412S for a mildly modified 318 will outperform the 7503 on a stock or mild 318. You can find a ton of poly A info on this website Poly 318 Intake Manifolds - Poly318.com

Thanks, I will check that out. Just got back from reading the intake section there. Lot's of great information. Thanks again.

 

[toolmanmike]

Good thing I asked here before I bought up a bunch of parts I didn't need. It looks like I may have a couple intakes for sale soon. (yes I have 2) I think it would be best to get a kit for my carb and make it happy again. A new filter and some fresh gas and I should be set.

If any of you have any more comments, post away. It's always good to get more information or a fresh prospective.

Thank you all.

 

[toolmanmike]

Good thing I asked here before I bought up a bunch of parts I didn't need. It looks like I may have a couple intakes for sale soon. (yes I have 2) I think it would be best to get a kit for my carb and make it happy again. A new filter and some fresh gas and I should be set.

If any of you have any more comments, post away. It's always good to get more information or a fresh prospective.

Thank you all.

I just ordered a kit from Mikes (that's a good sign there) $26 and $5 shipping. Ethanol ready and US components.
I always enjoyed rebuilding carbs. Like putting a model car kit together.

 

[Ron H]

Did a bunch of work on my ’63 poly, complete rebuild, mild cam, solid lifters, headers, installed a mopar electronic years before the rebuild replaced the perfectly fine 3:23’s to 3:55’s after having replaced the original rear to a ’65 edition (wish I hadn’t a done that gear change), Edle 650 on a stock ’62 manifold, upgraded TC. Remarkable change top, not that much bottom. Years before the rebuild had added a 4bbl and dual exhaust and that made more giddy-up.

A few members suggested curving the distributor to maybe obtain a bit more on the bottom. Something I haven’t got to with other projects, but hope to get to it in a few weeks. And something I shouldn’t have done was the way too-large exhaust for this motor. I don’t know why the shop machining the motor recommended it, but that’s that. Installed stock hemi mufflers later having a smaller diameter inlet/outlet after listening to the flowmaster 50’s, nice sound, but too loud for me. I had asked around about the aluminum manifold mentioned and was told it wouldn’t make for much difference. Not sure, but stayed with the one I have.
Wish my engine still looked this nice.

 

[66 Sat]

Did a bunch of work on my ’63 poly, complete rebuild, mild cam, solid lifters, headers, installed a mopar electronic years before the rebuild replaced the perfectly fine 3:23’s to 3:55’s after having replaced the original rear to a ’65 edition (wish I hadn’t a done that gear change), Edle 650 on a stock ’62 manifold, upgraded TC. Remarkable change top, not that much bottom. Years before the rebuild had added a 4bbl and dual exhaust and that made more giddy-up.

A few members suggested curving the distributor to maybe obtain a bit more on the bottom. Something I haven’t got to with other projects, but hope to get to it in a few weeks. And something I shouldn’t have done was the way too-large exhaust for this motor. I don’t know why the shop machining the motor recommended it, but that’s that. Installed stock hemi mufflers later having a smaller diameter inlet/outlet after listening to the flowmaster 50’s, nice sound, but too loud for me. I had asked around about the aluminum manifold mentioned and was told it wouldn’t make for much difference. Not sure, but stayed with the one I have.
Wish my engine still looked this nice.

Ron not sure if you're still running this rubber plug for the heater delete, but if you are I'd change it to a brass plug. I had one on the manifold nipple and it blew after a few years, made a big mess. Engine looks good!

 

[toolmanmike]

View attachment 1863104
Ron not sure if you're still running this rubber plug for the heater delete, but if you are I'd change it to a brass plug. I had one on the manifold nipple and it blew after a few years, made a big mess. Engine looks good!

Good eye. I have heard of those popping before. I was desperate so I just looped the hose. Not as neat looking but probably a bit safer.

 

[toolmanmike]

Did a bunch of work on my ’63 poly, complete rebuild, mild cam, solid lifters, headers, installed a mopar electronic years before the rebuild replaced the perfectly fine 3:23’s to 3:55’s after having replaced the original rear to a ’65 edition (wish I hadn’t a done that gear change), Edle 650 on a stock ’62 manifold, upgraded TC. Remarkable change top, not that much bottom. Years before the rebuild had added a 4bbl and dual exhaust and that made more giddy-up.

A few members suggested curving the distributor to maybe obtain a bit more on the bottom. Something I haven’t got to with other projects, but hope to get to it in a few weeks. And something I shouldn’t have done was the way too-large exhaust for this motor. I don’t know why the shop machining the motor recommended it, but that’s that. Installed stock hemi mufflers later having a smaller diameter inlet/outlet after listening to the flowmaster 50’s, nice sound, but too loud for me. I had asked around about the aluminum manifold mentioned and was told it wouldn’t make for much difference. Not sure, but stayed with the one I have.
Wish my engine still looked this nice.

View attachment 1863065

You did quite a bit of work to the ol' girl. She looks great. I have dual exhaust and electronic ignition but that's it. I can send the distributor to Halifaxhops for a advance curve and a look over. Some fresh fuel and rebuilding the carb, and I should be set. When it started acting up it was surging pretty bad and when I stopped, it sounded like it was running off half the carb.

 

[Ron H]

not sure if you're still running this rubber plug for the heater delete

Thank you much, great observation. My elder brother who’s a better mechanic than I am (I’ll never admit it to him) spotted that and another one you can’t see in the photo behind the thermostat housing. I did make the switch to brass plugs when redoing some of the cooling system after rebuild. Yeah, bypassed the core some years back after having a hell of a time to stop a leak at the heater valve. I think it’s just a matter of a correct O-ring. I have no shortage of those; but didn't have the one. A fellow member was kind enough to send me a correct one, though after a 2nd neck fusion, getting back to that chore might not happen unless there are more reasons to mess around in that area.