Drilling LA Heads for Magnum Intake

[kaharshs]

Once it is done and you are satisfied, will you be making more for sale OR renting that 1 out? Thanks for doing it.

I’m not sure what my plan is. I will likely need this one for another set of heads in the future. I may end up drawing a file to 3d print the jig. Im happy to fabricate one for others, but it would be at my standard shop rate.

 

[Killer6]

Once it is done and you are satisfied, will you be making more for sale OR renting that 1 out? Thanks for doing it.

Yeeaaahhhh......the rental thing would be a non-starter,....some c0ckhead made sure that ship pretty much sailed, I sure as hell wouldn't do it.......

 

[mopowers]

Yeeaaahhhh......the rental thing would be a non-starter,....some c0ckhead made sure that ship pretty much sailed, I sure as hell wouldn't do it.......

Certainly not without a sizable deposit.

 

[Kern Dog]

You may be able to find someone on this site that'll trade you straight across for an LA intake.

THIS ^^^^ is the best advice here.
This reminds me of the guy that bought a hat that was too small for him so he went to a surgeon to see about having his head shrunk to fit it.
I love low buck stuff to save money but come on, man...

 

[toolmanmike]

It's not that it can't be done but why? A Crosswind is what? $150. How much is your time worth? At $75/hr. Could you make a jig in 2 hours?

 

[kaharshs]

Kern Dog and toolmanmike​

Interesting how some people can't just say good job doing your thing. Redrilling my cylinder heads is literally no skin off of your back. My goal of posting this information here is to share information to others who may want to do the same thing. I have the available resources to redrill these heads, install an LA intake that is sitting on my shelf, or throw all this in the garage and buy a different set of cylinder heads. I have multiple projects going on, so I spend money in some instances to buy more expensive direct bolt on parts and then sometimes buyer lower cost parts that require more initial labor. I like my Edelbrock intake and want to keep it. I have a custom wiring harness, brackets, ac, coolant lines, and a thermostat housing with a hard pipe that would need to change if I go to a different intake. Come down from your pedestals and realize others may have more time than money and hot rodding and making stuff fit go hand in hand.

 

[volaredon]

My thoughts on that crosswind intake is it's Chinese so no way

 

[MOPAROFFICIAL]

Yeeaaahhhh......the rental thing would be a non-starter,....some c0ckhead made sure that ship pretty much sailed, I sure as hell wouldn't do it.......

I hope that guy is found at some car show somewhere and gets his nose flattened and car doors kicked in.

 

[tonysrt]

I just put the $150 Chinese manifold on an LA 318. It was tough putting in the plugs to eliminate the magnum holes. The only other problem was I had to put spacers under the throttle and spring bracket to be able to bolt them down and still work properly. It starts and runs as good as the Edelbrock that was on it. With the price of the Edelbrock going through the roof, I figured I would save it for my 360/408 build. By the way the magnum holes are blocked by the manifold gasket so probably no chance of a vacuum leak.

 

[kaharshs]

I just put the $150 Chinese manifold on an LA 318. It was tough putting in the plugs to eliminate the magnum holes. The only other problem was I had to put spacers under the throttle and spring bracket to be able to bolt them down and still work properly. It starts and runs as good as the Edelbrock that was on it. With the price of the Edelbrock going through the roof, I figured I would save it for my 360/408 build. By the way the magnum holes are blocked by the manifold gasket so probably no chance of a vacuum leak.

When I installed my Crosswind on another 5.9 I have, I had the same feelings about driving in those plugs. I paid $120 new for that crosswind, paid $455 for my edelbrock performer rpm air-gap in 2023. I have a A-Premium intake on the 440 in my 87 D250. That fits well, so I am assuming their La/Magnum intake works too.

For anyone that wonders I paid $1068.54 for my Speedmaster cylinder heads, stainless 1.6 rocker arm kit, and a set of aluminum welded valve covers delivered to my house. This was during black Friday. I splurged and bought a B3 geometry kit for $260 and my smith brothers pushrods were $145. I have less than $100 in materials for the jig/drill bits/taps/ect to redrill the heads intake bolts. I plan to buy another set of speedmaster heads this black friday if they are only $804 again.

 

[rbkt65]

I applaud the DIY people. The RMD in Canada that kept the original tool should be ...... But that is a different story. I salute you sir and also understand not renting/loaning your tool as there are people out there that could f÷$k up an anvil with a feather or a ballon.

 

[kaharshs]

I decided to drill and tap the heads without threaded inserts. Everything worked well. I used a 1/4” end mill, then an F drill bit, and then a long tap. I didn’t drill the end holes all the way through so I needed to use a bottoming tap on them. Once I get the second head completed I will bolt them onto a spare engine block I have so see if all the bolt holes align and how the ports align.

 

[RustyRatRod]

Hay man, if you got the tools and the skills, more power to ya.

 

[kaharshs]

Well, guess my jig worked out. I bolted the heads and intake on a spare block. I do not like how little of factory magnum intake bolts engage into the new threads. I will either use longer bolts or studs to max out thread engagement.

 

[JDMopar]

Dumb question from a non-machinist! Would it help to make or by some aluminum Allen head bolts to screw into the existing LA intake bolt holes? Then drill and tap thru them? Would doing that offer more thread engagement?

 

[Cuda416]

Dumb question from a non-machinist! Would it help to make or by some aluminum Allen head bolts to screw into the existing LA intake bolt holes? Then drill and tap thru them? Would doing that offer more thread engagement?

I was thinking about something along these lines but it involved round stock and jb-weld. Sort of like what some people do before relocating pushrod holes before porting. Probably too late for that now but your idea is also interesting.

 

[kaharshs]

I imagine filling the LA hole with a plug would work. A solid insert with a larger OD would probably work well too. Something like a keensert.