Drilling a Magnum intake for '73 'J' heads?

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mayhem

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I want to run a TQ carb and have found an M1 intake with the spread bore carb flange but the intake to head bolt pattern is for a Magnum engine. Can this intake be drilled for the '73 iron 'J' heads I have? If not, is there a comporable intake that has a square mounting flange that can be opened up to the TQ spread bore size? I know there are adapters for mounting a TQ on a square carb base intake but carb to hood space will already be at a premium so an added spacer is out. Maybe milling the intake & welding on the adapter? I'm not concerned with form so much as function. I'm open to any & all ideas. Thanks.
 
Which M1 intake are you looking at? Mopar made more M1 manifolds than you can shake a stick at- they applied the name to all their manifolds for a while.
Anyway, there probably isn't a snowball's chance in he// I'd bother trying to butcher up a manifold that
A.) isn't the right intake pattern.
B.) isn't right for the carb I want to run.
You may as well cut up a Chevy 2 bbl. manifold to fit it- about the same amount of work.
How about just getting the correct manifold?
Like this M1, among others:
1728828737285.png

Or this Performer:
1728828925296.png

Or even a stock manifold:
1728829028308.png

There's tons of options out there that require no hackery whatsoever.
 
Magnum M1's are no longer being made and bring good coin. I'd sell it and buy an LA intake. Plenty of those to choose from.
 
Mopar part number P4452891.
That’s the number in the catalog and on the box.
It is not the “casting” number(the number on the manifold itself).

IMG_3709.jpeg
 
Do not modify that intake manifold. It's worth far more than its LA equivalent, probably close to double. eBay it and find a Strip Dominator or Victor.

That being said, the Magnum holes are in virtually the same place as the LA holes. They're just at a different angle. The two different angles intersect at the head. Look at a Speedmaster intake to see what I mean. Could you do it at home? Probably. Should you attempt it? Probaby not, especially considering the value of the intake.
 
Which M1 intake are you looking at? Mopar made more M1 manifolds than you can shake a stick at- they applied the name to all their manifolds for a while.
Anyway, there probably isn't a snowball's chance in he// I'd bother trying to butcher up a manifold that
A.) isn't the right intake pattern.
B.) isn't right for the carb I want to run.
You may as well cut up a Chevy 2 bbl. manifold to fit it- about the same amount of work.
How about just getting the correct manifold?
Like this M1, among others:
View attachment 1716315134
Or this Performer:
View attachment 1716315136
Or even a stock manifold:
View attachment 1716315138
There's tons of options out there that require no hackery whatsoever.
This one:
1728857388930.png


I was unaware there was a sister intake to this Magnum pattern one. Thanks for the education.
 
Hughes Engines can drill the heads to match
They drill Magnum heads to the LA pattern.
I'm not aware of anybody redrilling LA heads to the Magnum pattern, although I'm sure it could be done; but why? The selection of LA manifolds is so much better anyways.
 
Ultimately I'd love to find a gently used (yeah, right) M1 as Prof Fate & Mr Porter have illustrated but I'll keep the Holley in mind if I run across a nice one. I'm a little leary of some of the clapped out examples on the Bag.
 
Ultimately I'd love to find a gently used (yeah, right) M1 as Prof Fate & Mr Porter have illustrated but I'll keep the Holley in mind if I run across a nice one. I'm a little leary of some of the clapped out examples on the Bag.
As others have correctly asserted, sell that beauty to somebody using Magnum/Magnum based/patterned heads, & use the coin to buy the correct one for Your project. What You need is floating around out there, patience & eyes peeled, You'll get what You want,....peace!
Jim K6
 
I want to run a TQ carb and have found an M1 intake with the spread bore carb flange but the intake to head bolt pattern is for a Magnum engine. Can this intake be drilled for the '73 iron 'J' heads I have? If not, is there a comporable intake that has a square mounting flange that can be opened up to the TQ spread bore size? I know there are adapters for mounting a TQ on a square carb base intake but carb to hood space will already be at a premium so an added spacer is out. Maybe milling the intake & welding on the adapter? I'm not concerned with form so much as function. I'm open to any & all ideas. Thanks.
Finally, someone using a Thermoquad
prep info here
Thx
 
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