Boss 429 Head Mercruiser 470 Intake Manifold - Lost Foam Casting

[@merylpelosi8485]

Oh, to be the automotive archeologist 100 years from now explaining how this hot rod had a boat motor with a Boss 429 head, a carburetor from a Trans-Am racer and an intake manifold that denies identification. Produced in an era of belly-button LS and Gen III Hemis. Keep up the excellent work and content.

[@cam3002]

Yea, can you imagine and angst of running a Marti report on the "factory" cast part number.

[@wayneprater8960]

@@cam3002now that brings a whole other level to that above statement 😂🤣 poor future person!!

[@richvandervoort2950]

Gen 3 Hemis are belly buttons now. I thought the normal refrain was to put LS motors in everything, even Hellcats.

[@GooseGosselin]

Spicy pour, I'd need a step on the ground to be able to lift that. So well done, I actually like the carb look over the injection much better. Thank you for showing the machining process as well.

[@kellycoffield533]

I do use that steady rest as an aid but still managed to snag the shank on it on the way up and slopped a little spill out of the crucible. 40-50lbs of shank/crucible/metal makes this old man's back ache on high pours like that. Best, Kelly

[@rickhalverson2252]

Thanks again for sharing. You're at a whole different level than everyone else precision casting aluminum. For extreme details I've been playing with water glass spray and dusting with alumina pre-coatings. Microfine texture, 600+ grit range. It can withstand over 3,000 degrees, and it conducts heat tremendously, so much less chance of voids. You can try this in a small area like around your custom casting numbers. Before dipping. See if you like the finish.

[@jimruddy6083]

As always, nicely done! Plus a bonus gasket cutter demo!

[@RotarySMP]

Outstanding workmanship as always from you Kelly. Thanks for sharing.

[@godsowndrunk1118]

I'd heard about those Mercruiser engines a few years ago... researched a bit, but then forgot about them. I did realize a Boss head would work and the lightbulb was flashing like crazy. Thanks for this reminder.

[@zebdeming]

These engines are super cool, great project!

[@kennethstaszak9990]

Quite the skill set you have. I'm impressed!

[@skypatrol716]

Really nice job Kelly and well documented video. Nice addition to the cnc with the drag knife.

[@tobhomott]

I never tire of watching you do this... You've been missed on the forums lately, hope all is well.

[@kellycoffield533]

J, you can contact me at the inlinecarb address on my carb website www.inlinecarb.com Best, Kelly

[@tobhomott]

@@kellycoffield533 your link brings up the following message: "This site is under development This page indicates the webmaster has not uploaded a website to the server. For information on how to build or upload a site, please visit your web hosting company's site." Not the only site I've had trouble accessing recently...

[@QuiltingJeri]

Anyone know what happened to the home foundry forums? The site has not been loading for some time now.

[@kellycoffield533]

J, the site is back up now. Was a glitch with hosting software. Thanks for letting me know. You can contact me at first email at bottom of home page. Sorry to put you through the extra step. I would like to speak with you. Best, Kelly

[@dave_ecclectic]

Very complete. From the fabrication to the filming. I for one don't fully appreciate the amount of work that you put into producing these. Thanks.

[@Enigma-Sapiens]

Absolutely fantastic work!

[@georgedreisch2662]

Kinda different that you didn’t employ your trapeze in this pour. Interesting project and thanks for sharing.

[@kellycoffield533]

It was small enought to handle freehand with an A20 and my smaller furnace. Best, Kelly

[@richb419]

Hi Kelly, nice to see you back, I look forward to your video's. very nice casting! I've always wondered if a vortex generator would be of benefit to the flow of a runner. your design could support a small one. What do you think? Rich

[@mgbrv8]

Again, another awesome video you know I tried to find something about that four-cylinder build, and I couldn’t find anything

[@kellycoffield533]

There's three or four related threads on the H.A.M.B. on these Merc builds. I can never find anything on that forum and seems more like a running blog.......but if YT will allow, here's a link to one of the threads-all 113 pages of it. www.jalopyjournal.com/forum/threads/the-elusive-224-3-7-mercruiser-banger.256713/page-113 Best, Kelly

[@craigmerrow225]

Built a Dave Gingery charcoal foundry years ago, made some cool stuff with it, but your setup is just fantastic!

[@Mercy-RHCR]

If you find casting materials, please contact me

[@makingcookingfixing]

Just amazing work, how skilled you are! Noticed you did not use the hoist this time, and the pour was quite high! The gasket making is another treasure trove. I have a vinyl plotter/cutter, I wonder if that knife could cut that material as well. Just amazing work!

[@kellycoffield533]

The knife may cut thin gasket stack on a cnc machine but I don't think a plotter would have enough grunt to cut a gasket. I have a video coming on drag knife cutting. Best, Kelly

[@roadrunner4404]

I love the possibilities of the mercruiser 4. I was thinking SCJ style aftermarket head. But a boss 429 head!!!!!

[@kellycoffield533]

It's hard to beat the appearance of the B9 head, and Kaase has made some significant improvements in his B9 offering but there are so many really good 460 heads these days that are both higher performing and more economical to build.....Kaase SR-71 comes to mind. Best, Kelly

[@wolfwind9658]

Your work looks factory. I'd like to make my own castings one day but I'll try making a 3d printed positive and then burn that out of the mold and cast it.

[@Felix-f2n6k]

Love your hotrod endeavors. So casual.

[@MrSmithDotShop]

Great work as always! What make and model is the drag knife? Are you modifying the leads to orient the knife?

[@kellycoffield533]

Stay tuned. I'll have a video shortly on the drag knife. It was a fairly short learning curve. Best, Kelly

[@boriskolnestrov9957]

Nice God bless your job you and yours👍

[@MLFranklin]

That is the coolest hot rod motor for a small car. How could you go wrong? Boss 429 head, Chevy bellhousing. I'm surprised it's not wildly popular. Isn't the block aluminum also? BTW, super cool project and video!

[@ParkerWhitlock-vp4rt]

Thought I was the only one messing with this engine glad to see there’s some others

[@kellycoffield533]

There's a Facebook group where you'll find many other builds and enthusiasts. Search "Mercruiser 470 Racing Group" on FB. Best, Kelly

[@skipper6567]

Im a marine mechanic so familiar with 3.7 mercruiser. Boat guys mostly hated these cuz charging system and overheating, iron head with alum block. I love the torque and fuel economy. Amazing the power from 4 cyl, 160 185 188 190 205 hp over the line sold. Weight to hp is great. I have several intakes alum, 2 and 4 bbl. Intake have coolant flow to cool. Seen 200hp per hole on turbocharged.

[@CL-ps7kh]

I bought a new 17-1/2' boat in 82 (I think) with a 470 Mercruiser. It had good power pulling a skier and IIRC it topped out at 50+ mph. I always wanted to get one of those engines and add a single turbo for a street rod but didn't follow through. My first vacation with that boat had a voltage regulator failure first day.

[@Rick.123]

What kind of cnc bits do you use in those styrofoam?

[@kellycoffield533]

Spiral double flute carbide. I have bought some that say they are specifically for foam but the rake and geometry is nearly identical to woodworking bits which work just fine. They wouldn't have to be carbide but my go-to bits are .25" diameter, 4" OAL, and 2" cut height and run them at 20krpm-24krpm. A long bit like that at that speed needs to be strong stiff material....thus carbide. I have some even longer 4 flute spirals in HSS but they need to be kept below 5krpm. Best, Kelly

[@chrispoirier384]

Not sure about your cad or cam, but if you lay down a sketch in CAD and put a c-sys in place (reference the sketch) on export you may be able to reference the c-sys it will be in position with no manipulation. Assuming you put the c-sys where you want it in CAM. C-sys position is CAM xyz zero.

[@driverjamescopeland]

Love it! Big fan of inline 4bbl work.

[@ThisIsToolman]

I fancy myself as a pretty clever fellow with a few patents to my name, able with respect to most trades but you, sir, are incredible. I pale in comparison.

[@jamesolivier3192]

Can you explain the heat treat process?

[@kellycoffield533]

7-9hrs at 440-450F. That will produce ~T5 for A356 Aluminum. It can be done in a kitchen oven if you hide the knives from your wife. 😁 Best, Kelly

[@farhanchoudhre6962]

I was thinking how you cut that cylinder part with a hole. What do you use to glue them together

[@markmonroe7330]

Excellent presentation. Thank you.

[@kurtdobson]

Beautiful work!!!

[@wayneprater8960]

I’ve followed you since you were first experimenting and developing your methods you are getting more and more impressive with your skills. I have a question have you heard of someone using drywall mud thinned out as their refractory coating? What are your feelings about that and would you consider a test to see if it’s legitimate or even feasible when you are doing another pour?

[@littlenickie951]

I need this guy as a teacher

[@josecovarrubias5856]

Nice work, I appreciate showing dimensions for the head, wanted to ask if you happen to have the full dims including the vertical? They were out of the screen boundary.

[@jeremycrisp4488]

Awesome work!

[@StingerSecSol]

Fantastic video! Thank you!

[@Leaked_Dudes]

Fantastic vid!

[@jdsstegman]

Amazing work!!

[@jmumbauer]

Kelly, thanks so much for sharing. Can you use any filler foam on the pattern if you find a feature under-sized? Have you ever tried using the same 'imprint' method as you did with the gluing fixture when assembling the pattern? I noticed that your gluing fixture did a great job establishing/maintaining geometry, could you build that into the flange pattern cut?

[@BLECHHAUS]

beau ti full !! What is that pink stuff ya're using for the "lost foam" ?

[@DustinPaullus-ij5ju]

Ever thought about doing a "clean" intake manifold for a 6v71 that doesn't require the huge base and an adapter? Being that 6v71 blowers are readily available for dirt cheap, and they would look more correct for a v8 engine.

[@rufustoad1]

This is so amazing. I have soooo many questions but the biggest one is why do you not have a bunch of black smoke from the foam burning off? Can you do this same thing with aluminum bronze?

[@kellycoffield533]

I've worked very hard at that. It's a combination of casting and feed system design, proper permeability of the refractory coating, and pouring cup design. Most of my castings have high surface area/volume which is also helpful. Yes, other alloys are possible too with lost foam including iron. Best, Kelly

[@rivercityspeed]

What do you use for a refractory coating?

[@kellycoffield533]

Search my channel. There is a whole video "refractory Coatings" dedicated to the subject. Best, Kelly

[@philipmacduffie7612]

Holy crap. I have a boss headed mercruisuer but no intake. Was gong to machine one in billet but not for the a1000. Are you planning to sell the castings or was this a one and done?

[@kellycoffield533]

Not necessarily one and done, but if $1k for a billet intake is above your pain threshold, it wouldn't even get you 2 cylinders worth of one of my custom cast intakes. The Inline carbs alone go for North of $2500. I do have several Holley 4Brl designs for B9 and SCJ port but again, the process price doesn't care about the head and carb combo. Best, Kelly

[@kathysarmcandy1992]

How many hours from concept to finished pattern ready to cast?

[@carlmic7]

Hello, do you have time to do a couple of castings for me?

[@5150TJT]

Can these be made with a different top playe for other style throttle bodies. Will you sell these, just starting a project now with thise engine..

[@ParkerWhitlock-vp4rt]

Vary interested in a manifold I have a few designed that I was planing on machining for my trick flow headed stroker

[@rcadd1ct]

Would this manifold have benefited from a common vacuum port from all the runners?

[@kellycoffield533]

For the last 10 years or so I've done that with a thin port communication plate that mounts between the carb and the intake. -Much cleaner than external plumbing. Best, Kelly

[@markbjorlin9714]

Are you still running the front mount distributor like the mercruisers in boats used?

[@kellycoffield533]

The jury is still out on that. When I did the design work it didnt look like it was possible without totally compromising the #1 runner, so it was accepted from the beginning that it would require an offset or relocated distributor, or other electronic ignition options. But, after installing the intake, the distributor can be installed with the cap removed, and depending upon the distributor and cap combination, it may be possible. It's not my engine. I just made the intake. Best, Kelly

[@shaileshjalavadia6685]

What are the reasons for carbon defects in lfc process

[@kellycoffield533]

Carbon defects are more usually associated with iron LFC not aluminum and are due to an ineraction with the metallurgy of cast iron. The small flaw in this casting was located near the surface but within the casting under the small uncoated area on the pattern where feed system support structure was removed. It was likley a fold or localized mold destabilization caused by higher gas venting in that area. Could also have been just entrained air given it's proximity to the sprue. Best, Kelly

[@truehybridx1]

Where did you normally get your foam? 2 inch looks hard to come by

[@adrianarroyo5215]

lowes here in fontana ca has it for around $ 50 2" x 4' x 8'

[@jonathanderbidge598]

Hey kelly. I designed an intake plenum manifold. its much simpler than your intake runners and I am trying to find out how to make a lost foam casting jig out of it. However if you have no interest in helping me achieve this, could you point me in the right direction to have you do it for a cost?

[@kellycoffield533]

For what carburetor and what heads? What are the basic specs of your build and how will it be used? Best, Kelly

[@marciomila9264]

Muito bom essa izopor

[@donsheehan5144]

Genius

[@DustinPaullus-ij5ju]

Side note, I would be willing to send you a 6v71 blower if you send me a manifold😁

[@mightyfinejonboy]

a proper setup!! please get some proper boots to suit, the splash on the ground was your first heads-up...

[@michaeloboyle8798]

I don’t care what your wife says, you’re cool.

[@Blackcavallino]

This guy just did everything with his macines. What about little info how the actual casting has been made. If everyone had things like he owns i wouldn't need a casting.

[@kellycoffield533]

You could not have watched the video. The majority of the video is devoted to how the casting was made. In lost foam casting, a large portion of the effort is making the foam pattern, but the video also shows the actual pour. There is a lot of other process info in my other casting videos. As much as many KZbinrs would like to think they can learn everything there is to know about casting in a 15 minute video, it's just not realistic and if I tried to include every step and detail in every video, they'd be hours long, but if you subscribe or just merely browse my channel and invest a modicum of time, there is plenty of info available in those videos.

[@kisoia]

Great video, thanks! Your pours are smokeless compared to most foam casters I've watched, why is that? Looking forward to the next video :)

[@kisoia]

Hi Kelly - Off topic - do you know why the forum is down? I hope it's temporary :)

[@kellycoffield533]

I don't know the reason, but it was back up as of this morning. Best, Kelly

[@kisoia]

@@kellycoffield533 Yes, glad to see it's back. After what happened to the other forum, it makes me nervous :)