Sleeping Beauty wakes up

[shelbydoug]

The Super Snake supposedly ran 175 mph with a then day 2, modded high riser. My goal has always been to get there with a medium riser because that's what all the Cobra guys and racers preferred. I know anyone can drop in a modern bullet that could easily reach that number,so the goal was to get there with 50 year old technology. There is not much info out there that describes the car in detail so basically stock with some muscle under the hood is the premise im going off of. Doug I guess 178 is the number you need to be at.

I remember being on the track at Pocono. The Speedo showed roughly 176. it was blurry because looking down the track was more important. Dick Smith in his Cobra came blasting by. Perogie was running down the straits in his red 500 with the nose up in the air.

You would think that the air was rare up there?

[427heaven]

Doug- How did the speedo read 176 when it only goes to 140?

[shelbydoug]

It goes around 2-1/2 times. 

Smiths gauge. Cobra.

The drive gear was wrong. Actually 183 or so. 8,300 +/- rpm.

Fuel pressure gauge going 0 to 7 like a clock ticking...tick, tock, tick, tock.

ZOOM! There goes Smith zooming by, hunkered down under the windshield (no helmet either). 

[427heaven]

Dick Smith was quite a guy. Didn't he have the worlds fastest street driven Cobra? At 199 mph it wouldn't matter if he had a helmet or not if things went bad.

[Bigfoot]

Make sure ur wearing one My Friend!

[427heaven]

10-4 Biggie.....   Safety first time, and every time!

[427heaven]

After the turkey overload and pre Christmas cheer I was able to spend a little more time on said project. Some fine tuning on the (twins) 750 cfm carbs, seems to be happy with some more cfm. Power output is in line with the SUPER SNAKES, after reading the recent hoopla of the SS it has got me more motivated to finally finish things up. I am curious about the ss gear ratio, anyone know if it was a standard 2.80 ratio or a custom gear set built for the test runs?

[FL SAAC]

+1 good to hear you are making progress

After the turkey overload and pre Christmas cheer I was able to spend a little more time on said project. Some fine tuning on the (twins) 750 cfm carbs, seems to be happy with some more cfm. Power output is in line with the SUPER SNAKES, after reading the recent hoopla of the SS it has got me more motivated to finally finish things up. I am curious about the ss gear ratio, anyone know if it was a standard 2.80 ratio or a custom gear set built for the test runs?

[shelbydoug]

After the turkey overload and pre Christmas cheer I was able to spend a little more time on said project. Some fine tuning on the (twins) 750 cfm carbs, seems to be happy with some more cfm. Power output is in line with the SUPER SNAKES, after reading the recent hoopla of the SS it has got me more motivated to finally finish things up. I am curious about the ss gear ratio, anyone know if it was a standard 2.80 ratio or a custom gear set built for the test runs?

It was a 2 something. 2.50's are the lowest I've ever heard of. The 427 GT40's at Lemans had such a lower gear that they needed a push start to get going.

Considering that the limiting factor then was lack of high rpm valve spring technology and 7,000 rpm was the absolute limit, find a gear calculator, factor in the rpm and see what that would suggest. I'd think that the 2.50's were is order?

I have a little experience with the lightweight 427 components. The heads are a 50/50 proposition with not breaking, holding head gaskets and the sodium filled exhaust valves liked to snap the valve stems. ESPECIALLY with headers.

The scavenging effect they create permits "cold" are from hitting the valve stems which makes them brittle.

It was not what anyone would consider a reliable engine.

[Bob Gaines]

After the turkey overload and pre Christmas cheer I was able to spend a little more time on said project. Some fine tuning on the (twins) 750 cfm carbs, seems to be happy with some more cfm. Power output is in line with the SUPER SNAKES, after reading the recent hoopla of the SS it has got me more motivated to finally finish things up. I am curious about the ss gear ratio, anyone know if it was a standard 2.80 ratio or a custom gear set built for the test runs?

It was a 2 something. 2.50's are the lowest I've ever heard of. The 427 GT40's at Lemans had such a lower gear that they needed a push start to get going.

Considering that the limiting factor then was lack of high rpm valve spring technology and 7,000 rpm was the absolute limit, find a gear calculator, factor in the rpm and see what that would suggest. I'd think that the 2.50's were is order?

I have a little experience with the lightweight 427 components. The heads are a 50/50 proposition with not breaking, holding head gaskets and the sodium filled exhaust valves liked to snap the valve stems. ESPECIALLY with headers.

The scavenging effect they create permits "cold" are from hitting the valve stems which makes them brittle.

It was not what anyone would consider a reliable engine.

I think it was a reliable engine if you consider the context of how the lightweight engine was used. It was very reliable in the context of how it was used which apparently was one time on a rebuild. Otherwise the GT40 program wouldn't have been so successful . Heads and valves were reported to have been replaced after every race. That coupled with the relatively low compression of around 10.2 to 1 made for a very reliable long distance race engine in the context of how it was used. I think anything longer term then one race or heaven forbid more compression like 427's like it then it was a ticking time bomb given the head and valve train IMO.   

[shelbydoug]

Hum? If one considers it a race engine, reliable for only one race, I would agree that it was successful considering it's race history, yes. I would also agree that is the context of which it was intended.

The sodium filled exhaust valves however were standard equipment in 427MR's as well and certainly weren't changed after every run around the block.

In the days when I was actively seeking a 427 Cobra (the early to mid '70s), I couldn't understand why so many cars with under 8,000 miles had failed engines or had replacement engines.

In the context of a street engine, from what I saw, even the MR could not accurately be described as reliable, but then I think a reliable engine should last at least 50,000 miles. I guess then that a 100,000 mile engine is a miracle engine?

You and I just have a different definition of reliable I suspect? That's ok though. The most desirable cars from the '60s now were some of the most impracticable for every day use then. Terms change. 

[Bob Gaines]

Hum? If one considers it a race engine, reliable for only one race, I would agree that it was successful considering it's race history, yes. I would also agree that is the context of which it was intended.

The sodium filled exhaust valves however were standard equipment in 427MR's as well and certainly weren't changed after every run around the block.

In the days when I was actively seeking a 427 Cobra (the early to mid '70s), I couldn't understand why so many cars with under 8,000 miles had failed engines or had replacement engines.

In the context of a street engine, from what I saw, even the MR could not accurately be described as reliable, but then I think a reliable engine should last at least 50,000 miles. I guess then that a 100,000 mile engine is a miracle engine?

You and I just have a different definition of reliable I suspect? That's ok though. The most desirable cars from the '60s now were some of the most impracticable for every day use then. Terms change. 

Doug,I am skeptical that the sodium filled valves were standard equipment on the typical factory 427 MR. You do have me second guessing what I remember. I understood The hollow stem and sodium filled valves to be a high performance extra. I pulled out the 1966 Ford High Performance guide to double check and under 427 engine specs it list forged steel-chrome plated stem. In 66 I can only assume it is the medium riser. You can understand why I am skeptical. Respectfully help me understand your point of view with further documentation .

[shelbydoug]

Hum? If one considers it a race engine, reliable for only one race, I would agree that it was successful considering it's race history, yes. I would also agree that is the context of which it was intended.

The sodium filled exhaust valves however were standard equipment in 427MR's as well and certainly weren't changed after every run around the block.

In the days when I was actively seeking a 427 Cobra (the early to mid '70s), I couldn't understand why so many cars with under 8,000 miles had failed engines or had replacement engines.

In the context of a street engine, from what I saw, even the MR could not accurately be described as reliable, but then I think a reliable engine should last at least 50,000 miles. I guess then that a 100,000 mile engine is a miracle engine?

You and I just have a different definition of reliable I suspect? That's ok though. The most desirable cars from the '60s now were some of the most impracticable for every day use then. Terms change. 

Doug,I am skeptical that the sodium filled valves were standard equipment on the typical factory 427 MR. You do have me second guessing what I remember. I understood The hollow stem and sodium filled valves to be a high performance extra. I pulled out the 1966 Ford High Performance guide to double check and under 427 engine specs it list forged steel-chrome plated stem. In 66 I can only assume it is the medium riser. You can understand why I am skeptical. Respectfully help me understand your point of view with further documentation .

I guess this is just the difference with comparing eye witness testimony with printed data? In my case, I just talked to about a dozen owners and the discussion was why there were so many engine failures. I interpreted that there was a consensus blaming the sodium filled exhaust valves.

Continuing that train of thought, I remember written discussions, or maybe mentions of that in past posts going back to the Cobra Club. I never cross examined those testimonies.

Unfortunately, I don't have a library of printed documentation here and wouldn't know if there was an early engine version and a running change version? Some people to this day, still quote early printed versions of the SAAC Registry of the number of Dealer installed 427's as fact?

When people ask me a specific question I always tell them to ask you. "Ask Bob. He'll know".


I remember that when the Warren Commission released it's report on the Kennedy assassination, they had received testimony from 5,000 or so eye witnesses. The problem was that much of the testimony directly contradicted others. So they had to make a decision on what testimony to accept and what to deny.

Not being an attorney, I'd pick a simpler explanation/solution. Groucho Marx once said, "who you going to believe? Me or your lying eyes?" 

[427heaven]

Since the question was brought up if sodium valves were original equipment for 427s I felt the need to ask around. Since my love of these engines occurred after the originals were thoroughly used and abused asking those that were around then and built many of them, their answer is it was not customary to run them on the street, and were ordered typically from racers of that era and not hot street performance engines.

[427heaven]

With some talk about having a new place to post on here for Day 2 cars, I would like to submit my entry into this category.....