Question about SOHC history.

[Stunerable]

Hello everyone.

I have been a big Shelby Cobra fan for as long as I can remember. I have had 1 question for years that I've never found an answer to and I have tried very hard to find.

The question is why didn't Shelby use the more powerful "Cammer" engine in any of his 427 models in place of the less powerful low/med/high riser sideoiler? Was it simply a matter of race regulations? Was it cost? Was it due to the SOHC's heavier weight bias? It doesn't keep me up at night but close! It just seems to me that a guy like Carroll would want the most powerful engine possible for his creation.

Any direction on this matter would be greatly appreciated.

Joe

[mrmustang]

Originally Posted by Stunerable

The question is why didn't Shelby use the more powerful "Cammer" engine in any of his 427 models in place of the less powerful low/med/high riser sideoiler?
Joe

Cost
Availability
Cost
Reliability
Cost
Street-ability
Cost


Hope that answers your question.


Bill S.

[Cobra #3170]

In those days they were getting close to the same output from a NASCAR tunnel port which was used in the Lemans Mark IV with a lot less weight. Granted the cammer had way more potential output but in their state of tune no big advantage and lots of disadvantages already mentioned plus pkg.

[55312]

I just finished reading this. 'Ford: The Dust and the Glory' comes to Amazon Kindle | Autoweek It will answer anything you want to know about the cammer or anything else Ford racing related. The Kindle version is pretty affordable but the pictures (and there are a ton) are hard to see. The hardcovers are quite pricey.

Tim

[Tom Howland]

Bill,
You left out COST.

[Cobra #3170]

Originally Posted by Tom Howland

Bill,
You left out COST.

Strangely enough in 1967 I could buy a Cammer for the same price as a dual four single plane tunnel port but both were about twice the cost of a medium riser then. Maybe because I was getting them through Bill Strope and Ford was trying to get them into racing applications. I was very surprised at the cost but the weight and bulk over ruled the appearance factor.

[Bill D]

CS put 428 FE in most of the 427 cars because they were more readily available and cheaper

[RICK LAKE]

Stunerable Joe I will take a shot at this.
First off having a limited supply of 427 motors caused CS to use 428 motor in the cars. We don't know( I wasnot there) is if Shelby told the people he went to 428 motor because they where easier to get. The 428 made more torque than the 427 at a lower rpm. Either way this car would fly.With the gas they had in those days, 12.5- 14.5 compression was doable and silly power was there. If you where crazy a little nitro meth don't hurt for a couple more ponys.Compression was 10.5 for 428 and 12.5 or higher for 427 SO.
Back to cammers, Foot box had to be modified. Getting the motor into the chassic, I think it was easier to lift and drop body on chassic after motor was in. I know you need 2 shoe horns and 5 pound of axle grease to get them into a cobra. The 6 foot timing chain, My feeling is this, lack of enough oil to cool the chain while running. The fact of no auto adjuster to keep the slack out of it for more accurate timing of the camshafts. I know on setup the guys have 4 degrees advanced and 4 degrees retard on the two heads.
I also think that the 427 LR then MR then HR and where designed and built already. If it was not for the Nascar issue with the hemi killing Ford, or NHRA and IHRA prostock racing the cammer would never had made it off the table for building.
I think for a long race of 3+ hours I would think that there was a issue with oiling of the heads and rocker shafts in the cammer. Over the years the guys learned to add return pipes to get the oil back to the crank case and also add better oil supply to the rocker assemblies. I also think that the chain would stretch and cause failures. Direct oiling and good steel chains would fixsome of this problem. I believe the guys running cammers are running a different style of chain to better control wear and stretch.
Power and rpm range cammer gets the win. Pushrod motor valvetrain in those days had it's limits. OHC where only limited by the motor bottom end.
I read that it cost silly money to make the 1,000 motors and parts for the cammer. We where lucky that ford wanted to win at everything in those days.
Shelby idea of keeping it simple added to why the cammer was not in lemans. 1 carb not 2 carbs, less moving parts to loose or break. Less power but better fuel mileage. I think that there was the idea of running at a lower rpm over having to whine up a cammer to get the same power output. Less revs, same power, longer life on motor and less wear on drive train. Maintainance during the race would also come into play.Less time in the pits, more time on the track.
I think we had aluminum heads on both motors in those days, so weight would be a wash.
Cammer is a great motor. the design has changed but the basic idea is alive and living today with most motors. Found an article, even GM tryed to build a cammer motor.
If I had silly money, the parts are being made again it would be cool to install a 500 cube cammer in a cobra. The problems of rockerarms, oil returns, and oil supply are fixed. This is a streetable motor and one of the coolest to look at and hear running.
This is not 100% correct info but simple thinking and some info would lead to this guessing. have to remember this was 50+years ago. Same place but a WHOLE different time. Rick L.

[Ron61]

I looked at the cammer and then got a 427 Tunnel Port for most of the above mentioned reasons. I have seen a couple of Cobras with the cammer in them, one an original that the owner had put one in and had it up at auction. It never went for as much as one of the originals with the 427 that came in it did. As for the 428s in the origials, the first 60 were single four 427 comp cars and then in the middle of the 3XXX series he used the 428s and then at the end went back to the427 dual fours like I had in my Galaxie.

Ron

[601HP]

I bought a used SOHC 427 in 1996. Had planned to install it in a 1968 Mustang, but the project never happened. The engine hung on an engine stand for 4 years until I sold it.

One day I was staring at the SOHC motor while it was next to my Cobra, which had a 427 medium riser. I remember wondering how much wider it was than the wedge motor in the Cobra. Grabbed a tape measure.......8" wider. And HEAVY. There was a lot more cast iron weight in those heads. I stacked 4x4 wood blocks between the oil pan and the bottom frame of the engine stand to help support the engine. Without the 4x4's the engine's weight was slightly bending the upright portion of the stand.

Several times while looking back and forth at the wedge and cammer, I had no desire to put the cammer in the Cobra.

David

[mdross1]

When considering an engine for our car over 20 yrs. ago had the option of using a Boss, a Cammer or FE all engines needed machining and assembly. At that time the initial cost of the Boss and Cammer was incredible. That Ford racer talked me into a 385- 460 over the FE I liked his reasoning.
That Cammer sure is an engine you never get tired of looking at nor the Boss for that matter.

[mullen2]

I had a new all aluminum Cammer Built for a Kirkham Roller, after the long wait for all the correct parts I lost interest and sold the car, My friend still has the engine and transmission sitting on the stand. It was a big project and we were told it was better to take the body off the frame to install the engine. At that point I nixed the Cammer Cobra. It was just getting way to expensive. I think i ended up having over 50K in the engine and trans as a pair.

[mullen2]

1965 Shelby Cobra 427 SOHC engine picture | SuperMotors.net

[Ron61]

Darren Friedman had a flip top Kirkham with the cammer in it. He won several shows but tried racing it and the timing chain kept messing up. Those engines weren't built for the up and down revs like Darren does in his type of racing. But that was a great looking Cobra. Nearly everything on it was custom built by Kirkhams.

Ron

[strictlypersonl]

We (ERA) have done several SOHC-engined cars. The engine fits through the hood opening with a little care. What is problematic (for me) is that the footboxes must be shrunk quite a bit to fit the engine, the pedals must be moved over a couple of inches, and the dead-pedal eliminated.
The only car that I actually drove had a big cam in it. Not much torque (relatively speaking) until about 4000 rpm, until all heck broke out. Scarey to drive, but I'm a wimp.

[Stunerable]

Thanks so much guys. Funny, I've always LOVED the SOHC and dreamed of owning a Cammer Cobra done up like a full out competition model but after reading this I think a high riser side oiler would be the better way to go.

Thanks again!

[legenmetals]

Here are a few pictures of my cammer project. Aluminum cammer in a Kirkham aluminum car how cool is that? That's Art Chrisman in the picture, He's building the cammer. I think that's even cooler

[damage]

There isn't much room left after you shoe horn a Cammer in.

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[mullen2]

Hey legenmetals,

Did you just buy the Kirkham Cobra recently? It looks like my old Kirkham Cammer I never finished. Did you buy it from Bill in Charlotte?

Small World! Happy to see the car will be finished as a Cammer Kirkham as I originally intended!

[legenmetals]

That is your car. I have a fiberglass car ready for the cammer but decided to put the cammer in an aluminum car.