Cadillac 542 Ultra - Branch Engine

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SWAMPHUNTER45
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Re: Cadillac 542 Ultra - Branch Engine

Post by SWAMPHUNTER45 »

Lifters in and pre-load set !
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Branch 542 cubic inch Cadillac<br />GDR542-Ultra
Branch 542 cubic inch Cadillac
GDR542-Ultra

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Re: Cadillac 542 Ultra - Branch Engine

Post by SWAMPHUNTER45 »

Detail pic of roller shaft rocker system - stainless
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Stainless custom shaft roller rocker system<br />Cadillac 542 cubic inch
Stainless custom shaft roller rocker system
Cadillac 542 cubic inch
Shaft Rocker pic close up 542.JPG (43.81 KiB) Viewed 2000 times

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BluByU2
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Re: Cadillac 542 Ultra - Branch Engine

Post by BluByU2 »

Nice photos Erik! That beast performed extremely well yesterday. You have to be really happy with the way it moved carrying everyone it did.

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Re: Cadillac 542 Ultra - Branch Engine

Post by SWAMPHUNTER45 »

I am actually kind of thrilled with the fuel usage too so far it is very reasonable. Have about 20 build pics to post up but they are over the 2mp size to it has taken me quite an effort to transfer them and post up. This build we did not take as many as the 514 but have a few good ones left.

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Re: Cadillac 542 Ultra - Branch Engine

Post by SWAMPHUNTER45 »

Mounted up to the run stand
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542 cubic inch Cadillac - on run stand
542 cubic inch Cadillac - on run stand

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Re: Cadillac 542 Ultra - Branch Engine

Post by SWAMPHUNTER45 »

On the rigging
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542 starboard view.JPG

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Re: Cadillac 542 Ultra - Branch Engine

Post by SWAMPHUNTER45 »

On the rigging, ready to go!
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542 port view.JPG

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Re: Cadillac 542 Ultra - Branch Engine

Post by SWAMPHUNTER45 »

Stern view
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Sensenich S blades on Branch 542 Ultra
Sensenich S blades on Branch 542 Ultra

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nebraskaairboater
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Re: Cadillac 542 Ultra - Branch Engine

Post by nebraskaairboater »

I'm just curious what ratio the box is, what is max rpm, and what pitch mark are you running? I wish I could swing 3 blades let alone 4 efficiently. My 2 blade S impresses me most of the time for straight push.
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16 x 8 1971 Flat Bottom Fiberglass Hull / 454 Chevy/ 2.38:1 OX Drive / 80" 3-Blade Sensenich S

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Re: Cadillac 542 Ultra - Branch Engine

Post by SWAMPHUNTER45 »

This boat has been anything but a simple build and I would really like to give recognition to my friend Allen aka BluByU for all the help putting it together and then together again!

We tried to keep it simple and continue with the direct drive Cadillac heritage we so much enjoy but this boat just got to big and heavy. We took DD to it's limits and I was just not getting the reserve power that was needed to feel safe in some dry situations so going with a gear drive became a need. If we were going to go through the effort to re-fabricate then why not go all the way and make it a beast. After more than a year of collecting some very unique parts we went full speed ahead and started the build.

Engine: Cadillac base
Cataloged: Branch GDR542-Ultra

Block bored .080, line bored, decked, stainless freeze plugs
Crank: 500 Cadillac off set ground (stroked) and journals widened
Rods: Eagle BBC H Beam forged
Bearings: bi-metal race alloy
Pistons: Cadillac Performance Engineering specification produced by Weisco-forged
Oil Pump: Cadillac Performance Engineering blueprint
Pulleys: MTS
Cam: Competition Cams - roller, custom grind
Lifters: Competition Cams- roller
Heads: MTS raw cores by Edelbrock foundry hand worked by Mr. Branch
Machine work: TopLine 4 angle valve work
Shaft Rocker- custom stainless roller
Gaskets: SEC / Fel-Pro and custom hand cut
Intake: Edelbrock with modified plenum
Carburetor: Edelbrock Thunder AVS 800cfm
Drive: Rotator 2.37 (Panther)
Prop: Sensenich 4x"S" 81 inch (Outlaw Aircraft)
Nitrous: NOS 150hp via manual arming

billybob
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Re: Cadillac 542 Ultra - Branch Engine

Post by billybob »

Do you have a ball park on the HP and Tq numbers? What RPM and pitch is the prop?
I do all my own stunts!!!!!!

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BigDaddyT
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Re: Cadillac 542 Ultra - Branch Engine

Post by BigDaddyT »

SWAMPHUNTER45 wrote:This boat has been anything but a simple build and I would really like to give recognition to my friend Allen aka BluByU for all the help putting it together and then together again!

We tried to keep it simple and continue with the direct drive Cadillac heritage we so much enjoy but this boat just got to big and heavy. We took DD to it's limits and I was just not getting the reserve power that was needed to feel safe in some dry situations so going with a gear drive became a need. If we were going to go through the effort to re-fabricate then why not go all the way and make it a beast. After more than a year of collecting some very unique parts we went full speed ahead and started the build.

Engine: Cadillac base
Cataloged: Branch GDR542-Ultra

Block bored .080, line bored, decked, stainless freeze plugs
Crank: 500 Cadillac off set ground (stroked) and journals widened
Rods: Eagle BBC H Beam forged
Bearings: bi-metal race alloy
Pistons: Cadillac Performance Engineering specification produced by Weisco-forged
Oil Pump: Cadillac Performance Engineering blueprint
Pulleys: MTS
Cam: Competition Cams - roller, custom grind
Lifters: Competition Cams- roller
Heads: MTS raw cores by Edelbrock foundry hand worked by Mr. Branch
Machine work: TopLine 4 angle valve work
Shaft Rocker- custom stainless roller
Gaskets: SEC / Fel-Pro and custom hand cut
Intake: Edelbrock with modified plenum
Carburetor: Edelbrock Thunder AVS 800cfm
Drive: Rotator 2.37 (Panther)
Prop: Sensenich 4x"S" 81 inch (Outlaw Aircraft)
Nitrous: NOS 150hp via manual arming

Thanks for the build sheet SwampHunter. Keeps us Cadillac boys drooling and dreamin' .
13' 6" Combee Hull with 472 Caddy. Whirlwind Whispertip 72" Prop

SWAMPHUNTER45
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Re: Cadillac 542 Ultra - Branch Engine

Post by SWAMPHUNTER45 »

As far as the numbers go for hp output Mr. Branch offered me the opportunity to send it out for dyno but I opted out.

Those blades are pitched 2+ and they seem very efficient in this range with a blade speed of apx. 1800 rpm - lots of push

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John C
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Re: Cadillac 542 Ultra - Branch Engine

Post by John C »

Congrats on an awesome build. Looks like you got it dialed in just right.

Olf Art
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Re: Cadillac 542 Ultra - Branch Engine

Post by Olf Art »

Awesome motor, man. Congratulations!
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SWAMPHUNTER45
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Re: Cadillac 542 Ultra - Branch Engine

Post by SWAMPHUNTER45 »

Thanks JC and Olf it was a long road to get it together with about 6 months of down time for the re-fab and build.
Having gotten a Branch engine before and spending time around the shop I wanted to let him build something of a challenge and some of the pieces kind of just fell into place. The crank was cut over 15 years ago and had traded hands twice before I took on the stroker project. The man who had it was up in years and wanted a new Branch Series 3 roller engine. He had the stroker crank but was scared to go that route so I traded crank for crank with him giving him a virgin 500. He had purchased the forged H-beam big block Chevy rods (Eagle) and we made a deal with him to help him get some standard size Scat rods. The pistons matched the heads fairly well and put us at the very edge of pump gas so we blend in a little race fuel as insurance against detonation.

The great news with this is it has Mr. Branch excited and looking at some real exotic combinations which may keep Cadillac alive a little longer since cranks are a hard part to find these days. He is on the edge of building a 570 cubic inch direct drive at the moment to see what the outer limits of that build could yield. Then going the other way for smaller hulls, he has a blueprint cooking for a ultra light Caddy build that could bring 500+ cubic inches in a package 75 pounds lighter than a small block. None of it would be cheap but for a Cadillac fan who has the coin it would be something to put a smile on your face.

In my hunt for parts I stumbled across a barn find of some aluminum head cores of unknown origin in Kentucky that are tall port of an LS3 type design. It may be another thread one day here soon as they were totally raw. They did not even have seats or guides and required extensive machine work to finish. The plan was to use them on the 542 build but Mr. Branch said he had never in all his years building Cadillac seen a set of heads this capable and felt they would be wasted on an engine that was built for lower rpm power. So that is what led us to then get the raw MTS-Edelbrock cores from the Lane family and go that route. I still have the proto type heads in the closet for the future just need to figure out what to build that needs big cubic inch engine turning up lots of rpm's. Maybe an old Nova one day, I already have a light weight crank and rods put aside so time will tell.

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