The trifecta of engines...

[blykins]

There used to be only one style of timing chain and there are some better chains out there now. A lot of the guys are pinning the gears together and are incorporating some extra oilers as well.

[Buzz]

I've been fascinated by the cammer since I first read about it many years ago, so I really do get the wow factor of having one under the hood of a Cobra. Based what I've seen and read lately since the "revival" of the once exotic and elusive SOHC however, I have to ask the following question: Other than the stated wow factor and associated prestige is there any point to putting one in a Cobra?

The last two well publicized Cobra installs that I can remember - both in Kirkhams - are Darren's flip-top cammer and Damage's car in Australia; and both failed after a little bit of spirited driving. Is the old, long chain SOHC tech just plain outdated and too fragile/fussy/finicky for practical use in anything other than a limited cruising car show queen, or can it be made to function reliably (in the context of hi-po engines, of course) for exuberant street and occasional mild track use in a Cobra? Do they offer any real benefits in the way of actual, useable performance?

[blykins]

I'll be straight up and say that I'm not a cammer expert. When these things cost over $40k, no one really sells enough of them to be an "old hat" at them.

From what I can tell, there are nicer, beefier parts out there now, made by 1 or 2 suppliers. Most of the issues I have seen have been timing chain issues.

As far as performance, in my mind, they are up there with Boss 9 stuff. The heads perform extraordinarily well, and when coupled with some displacement, it can make for some big hp without having to run high rpms or high compression. It's not uncommon to see 700-750 hp out of these engines without really trying hard.

[Dimis]

Nice builds... This one in particular will be fun to watch come together.

Originally Posted by Buzz

The last two well publicized Cobra installs that I can remember - both in Kirkhams - are Darren's flip-top cammer and Damage's car in Australia; and both failed after a little bit of spirited driving.

On a separate topic...

Buzz - do you know if those two Cammer engines were built by the same engine builder?

[blykins]

I think a lot of the failures come from the use of an aluminum chain tensioner. They will directly cause chain failures. There have been several "upgrades" for the SOHC engine and a lot of nice parts have come out lately. Robert Pond is making a ductile iron tensioner which won't flex like the aluminum one and there are some new chains and gears out there as well.

Robert has done some Spintron testing as well, while he was R&D'ing his own SOHC heads, which helps with valve spring selection...

[ACademic]

I'm really looking forward to LEARNING something with this build. Thank you.

"Knowledge is good." -Emil Faber , Faber College

[Buzz]

Thanks for the info and the build thread, Brent. Always interesting to see the detail you go into with your builds.

Originally Posted by Dimis

On a separate topic...

Buzz - do you know if those two Cammer engines were built by the same engine builder?

I do know the answer, but since this is Brent's build thread, I'd rather not go into that here.

[Dimis]

Originally Posted by blykins

I think a lot of the failures come from the use of an aluminum chain tensioner. They will directly cause chain failures. There have been several "upgrades" for the SOHC engine and a lot of nice parts have come out lately. Robert Pond is making a ductile iron tensioner which won't flex like the aluminum one and there are some new chains and gears out there as well.

Robert has done some Spintron testing as well, while he was R&D'ing his own SOHC heads, which helps with valve spring selection...

If I recall correctly, and understand it right, I believe Damage's Cammer was damaged in part by a flexy chain, or a suspect chain or... something along those lines. So that seems to validate your conclusions Brent.
Customer can rest easy

I must say I'm super curious on the intake... any hints?

Originally Posted by Buzz

I do know the answer, but since this is Brent's build thread, I'd rather not go into that here.

Ahhh... Yes of course... My apologies.
Carry on...

[blykins]

It will probably be one of Robert's dual carb intakes. I may try and see if Paul Munro has any single carb single plane pieces, as it would be easier for my customer to keep it tuned and running.

[Barry_R]

When you are building these a couple things are IMPORTANT as far as the chain package goes. First is to NOT USE any chain that has the name ROLON stamped on the links. They are made in India, and the only two chains I have ever broken both came from them. One of those two was a Cammer and it cost me a ton of money to fix. They are a very common supplier for private branded stuff, and are suppliers for some of the Cammer sets out there.

Next is to look very, very carefully at the chain alignment relative to the block, heads, and sprockets. I think the aluminum tensioner is getting the blame for other issues. When we assembled our first all aftermarket Cammer we discovered that the stands, heads, tensioners, block were not in good agreement as to "front to back" alignment. We ended up doing a fair amount of machining/correction and it was amazing how much smoother the engine turned once that was straightened out.

[Buzz]

Interesting Barry, and makes perfect sense. I'm familiar with the gear drive arrangement - surprised that isn't used more instead of the chain. Also, to echo 750HP's post earlier; wouldn't a belt and pulley system be more durable and forgiving?

[cycleguy55]

Originally Posted by Buzz

Interesting Barry, and makes perfect sense. I'm familiar with the gear drive arrangement - surprised that isn't used more instead of the chain. Also, to echo 750HP's post earlier; wouldn't a belt and pulley system be more durable and forgiving?

The gear drive seems to make sense, especially with the chain issues and the possibility of catastrophic failure.

Thread on this from 2003: cammer heads

[Bernica]

Originally Posted by Buzz

Interesting Barry, and makes perfect sense. I'm familiar with the gear drive arrangement - surprised that isn't used more instead of the chain. Also, to echo 750HP's post earlier; wouldn't a belt and pulley system be more durable and forgiving?

I remember seeing and hearing a cammer with the full gear setup instead of the chain. Lots of gears
But it seemed to worked well once you got used to the added noise of the gears all whining a bit!

[blykins]

Originally Posted by Buzz

Interesting Barry, and makes perfect sense. I'm familiar with the gear drive arrangement - surprised that isn't used more instead of the chain. Also, to echo 750HP's post earlier; wouldn't a belt and pulley system be more durable and forgiving?

I was talking to Robert yesterday about parts availability and had a rather lengthy discussion with him. I think he has probably built more SOHC FE's than anyone else, from a "crate engine" standpoint.

He told me that the ability to stay together and be reliable is equal to the wedge headed FE, but you have to use the correct parts. He said the first one he ever built wore the aluminum tensioner out on the dyno. It flexed and then if he tightened the chain up so that the tensioner wouldn't flex, it would break the chain. I think Ed Pink told him that Ford tried the aluminum tensioners back in the day and just determined that they didn't work. Robert ponied up and started having the ductile iron tensioners made.

From what I understand, the two engines that were mentioned earlier in this post that failed were due to aluminum tensioners.

But again, the SOHC is an engine where we have to compare notes with each other. They cost so stinkin much that: 1. We don't get the opportunities to play with them as much. 2. If you have a failure, it's gonna cost some bucks to fix it.

[rodneym]

Brent,
Does the warranty on an engine like this differ from Wedge engines?
Do you warranty labor but not parts, and for how long, etc.?

[blykins]

If it's a street engine, then it gets the same warranty as the others. Essentially the short and skinny of it is if it breaks because of something I did wrong, then I'll fix it. If it breaks because of something you did (or an installer did) or a parts manufacturer did wrong, then I'll help out the very best I can.

I provide 1 year limited warranties on my stuff.

Here's the long and fat of it if you're interested in reading:

Lykins Motorsports, LLC

I haven't ran into a lot of issues (knock on wood), but I think that those customers will attest that I do a good job of taking care of things.

[Barry_R]

Only thing I really saw with the aluminum tensioner is that the fasteners sunk into it pretty easily & loosened. You needed to use a fat washer (like on a cam or damper) to get enough crush on it. Probably should be using a better alloy. You could CNC a chunk of steel pretty easily for that item...might have been cheaper than casting them.

[Barry_R]

And I personally don't think chain stretch is as big a deal as you might think. Consider the length of a 4.6L Ford chain from drive sprocket to driven sprocket - - the cam to cam distance on a Cammer ain't so large in comparison.

I degree in the lead cam (driver side), then degree in the trailing cam (passenger side). the newer lobes we've developed with Comp are significantly better from the old stuff and will deliver the same valve action side to side even though the lobes themselves are very different.

[legenmetals]

I scrapped my aluminum tensioner after looking at the quality of the machine work on it. I found original ductile units for my two aftermarket cammers. I would like to point out that the aluminum heads have a standard 7/16 ( I think) bolt and jam nut that adjusts the tension on the idler arm and chain. The original adjusting bolt has an interference fit for the cast iron head. The interference bolt will eat the threads in the aluminum head. The standard s.a.e. bolt fits loose in the aluminum head so make sure that the jam nut is locked down tight or you may jump timing.

[Barry_R]

Originally Posted by legenmetals

I scrapped my aluminum tensioner after looking at the quality of the machine work on it. I found original ductile units for my two aftermarket cammers. I would like to point out that the aluminum heads have a standard 7/16 ( I think) bolt and jam nut that adjusts the tension on the idler arm and chain. The original adjusting bolt has an interference fit for the cast iron head. The interference bolt will eat the threads in the aluminum head. The standard s.a.e. bolt fits loose in the aluminum head so make sure that the jam nut is locked down tight or you may jump timing.

Ran into that issue too. Ford had some kind of fascination with interference threads back then. Interference threads are an evil and wicked creation which should be banned from the planet and erased from the memory of mankind.