351W F.O. changed to 289

[Bluesman]

What is the advantage of running a 289 cam in a 351W?
The reason I ask is that when I had a real reputable mechanic
(Dan Fodge) pull out the broke cam, he changed the firing order.
I noticed the plug wires out of wack when I picked the car up. He said it would perform a little better. I accepted that because every time I have had him work on the cobra he has done outstanding work. If I feel the job is over my head, I have never been bothered by the fact that I am paying someone else to do it
right.

[HighPlainsDrifter]

Hi,
The firing order for a 351 and a new 302[ 5L H.O. ] are the same. The old 289/302 firing order has been arond for ages and the cams are a bit cheaper to put a jobber cam in instead of a 351 cam. That's it, money. The power and emissions are better in a H.O. / 351 cam, that's the reason Ford changed it.
Perry.

[Bluesman]

HPD;
Thanks for the info. I'll let Dan know the next time I see that dirty dog.

[HighPlainsDrifter]

Hi,
Either firing order will work. There is a problem with the old firing order. Cylinder 8 fires right after 7 , they are next to each other and cylinder 8 will run lean if you have a open plane manifold. The wilder the cam, the worse it gets,as the overlap for 7 will kill the intake charge for cylinder 8. so it's better in performance applications to use the H.O. firing order.
Perry.

[EricF]

Hello, My name is Eric Fodge, I am a partner at Fodge Engineering, hopefully I can shed some light on this matter

Originally posted by HighPlainsDrifter



The old 289/302 firing order has been around for ages and the cams are a bit cheaper to put a jobber cam in instead of a 351 cam. That's it, money.


We installed a Clay Smith custom grind camshaft in the Engine in question, I pay the exact same amount of money, and charge the exact amount of money, for a 289 camshaft as I do for a 351 camshaft, So I call BS on your "That's it, money" claim.

Originally posted by HighPlainsDrifter



The power and emissions are better in a H.O. / 351 cam, that's the reason Ford changed it.
Perry.

Where are you getting your information, where is your "tech" to back up your claim? Do you have any, or are you just pulling this out of thin air?

Clay Smith Engineering has been in the camshaft business for over 60 years & the "Mr Horsepower" name is synonymous with High performance.

We (Fodge Engineering) have been a Clay Smith dealer for 30 years & we have a personal relationship with the owner, George "Honker" Striegel. We have literally designed 100's of camshafts over the years.

Clay Smith Engineering has done extensive dyno testing on various camshaft profiles, as well as various firing orders. They have found, through the results of their dyno testing that the "old" (15426378) firing order makes more power than the "new" (13726548) firing order.

As far as emissions are concerned, I have not done any testing regarding this. Automotive manufactures are held to increasingly tight emission standards, not HP limit standards, or another way to put it is that they will sacrifice HP to get better emissions, not the other way around, so I could make an educated guess that better emissions is the reason for the change of firing order.

Originally posted by HighPlainsDrifter



Either firing order will work. There is a problem with the old firing order. Cylinder 8 fires right after 7 , they are next to each other and cylinder 8 will run lean if you have a open plane manifold. The wilder the cam, the worse it gets, as the overlap for 7 will kill the intake charge for cylinder 8. so it's better in performance applications to use the H.O. firing order.
Perry.

With either firing order 15426378 or 13726548 you have 2 cylinders that are next to each other that fire consecutively (8 after 7 & 5 after 6) so once again BS on that claim.


I just got off of the phone with George from Clay Smith, to once again confirm my claim, like I mentioned before, he has done EXTENSIVE dyno testing & has dyno results that show 15-20 HP gains on a 351W by switching from 13726548 to 1542678 while maintaining the same exact cam profile.

Mr HighPlainsDrifter, how many camshafts have you designed?

How many high performance engines have you professionally built?

How much dyno testing have you done with camshafts?

Do you have any dyno results to back up your claim?


Thanks
Eric

[Wade Chamberlain]

Eric - can you explain the reasons why a given 351W would show that much of an increase in HP just because of a different firing order on the cam? Just curious.

[blykins]

For his first post, he didn't care about making friends did he? Funny.....I've never heard of Clay Smith cams.....Sorry....I just don't have any respect for someone who untactfully gets on here (1st post even) and gives his opinion with such arrogance and rudeness. If I had heard of Clay Smith cams, I wouldn't buy one for that reason.

[MidOHasp]

I agree. An unprovoked attack. Perry was making some points but didn't say anything to the effect of "Well, this Fodge guy's a real piece of $hit!"

Not nice, Mr. Fodge. You will have much better luck defending yourself (which you apparently felt the need to do) if you bring some tact with you next time. Others will be much happier to listen to you if they don't feel as if they are being yelled at!!

Fodge, Clay Smith, 2 names I will keep on my "no thanks" list.

Take a valium and go install a Clay Smith cam....

JP

[Mr.Fixit]

Clay Smith cams are fine, not my first choice, but OK. Fodge is not a representative for Clay Smith cams, and we all have our bad days every once in a while, don't we?

[EricF]

Originally posted by Wade Chamberlain

Eric - can you explain the reasons why a given 351W would show that much of an increase in HP just because of a different firing order on the cam? Just curious.

It all has to do with fluid dynamics & wave form technology, which one could spend a lifetime studying.

The R&D has been done, Clay Smith has the data to back up the claim.


Originally posted by Blykins

For his first post, he didn't care about making friends did he? Funny.....I've never heard of Clay Smith cams.....Sorry....I just don't have any respect for someone who untactfully gets on here (1st post even) and gives his opinion with such arrogance and rudeness. If I had heard of Clay Smith cams, I wouldn't buy one for that reason.

1. I did not come her to make friends, I came here to state fact, If someone is going to spew a bunch of nonsense out of his mouth, especially when it concerns myself, then he better at least have some tech to back up his claim, otherwise it's open season as far as I’m concerned.


2. You have never heard of Claysmith





ever seen this logo, this is the Claysmith logo, I am sure that you have seen it before.

3. Claysmith is not my company, don't penalize Claysmith because of my untactful ness. Penalize my company, don't buy Fodge Engineering products.

[blykins]

"1. I did not come her to make friends, I came here to state fact, If someone is going to spew a bunch of nonsense out of his mouth, especially when it concerns myself, then he better at least have some tech to back up his claim, otherwise it's open season as far as I’m concerned."

That's not the way we do things here....From my standpoint, if you come on here and attack others instead of saying "Well, we've done some dyno testing....I'll post the results....you guys may be surprised..." and being tactful, then you've lost my business and probably a lot of others on here.

I work for Valvoline....but my first post wasn't "You guys are wrong. It's a lot of BS if you use Mobil 1 or Pennzoil."

[EricF]

Sorry, I did not realize that there was a code for the way things are done here.


I apologize if I offended anyone & in the future I will try to be morte tactful



Thanks

Eric

[blykins]

Cool. Now do you have any dyno sheets comparing different firing orders?

[sport]

The 351W "1,3,7...." firing order more evenly distributes the firing load on the mains. The old 289/302 with its "1,5,4..." order had the #1 and #5 cylinders firing one after another on the front main which was double stressing the weakest part of the block. Not a good situation, so Ford revised it back in '69 when they created the 351W.

If you trace the firing orders out on paper, you'll notice how the 1,3,7.. order puts the stress on the center 3 main webs taking it off the front where the block is weaker.

The cam companies might have data showing that the old 289/302 firing order makes more power. But in a high output 351W based engine, Comp Cams told me to use the regular 351W firing order.

[MidOHasp]

Eric, welcome! We have no code, just the typical code of life. I didn't see anyone badmouthing you. Someone said maybe it was a "bit cheaper" and the reason was "the money" - I don't think anyone was talking about anyone screwing anyone!!

Now.... SOMEONE needs to explain to me how in the hell you can run a different firing order in the same motor. I think I figured it out on the way home from work today, but... not sure.

My assumption is that when you mix up the firing order, you are just altering which is a compression vs. exhaust (or intake vs. power) stroke? I mean, the crank would be the same, of course, right?

Thanks.

[blykins]

JP, the crank would be the same....just the cam lobes would be different. Different valves would open at different times....And of course you change the firing order on the distributor cap to go with the flow.

But yeah, you're doing exactly what you said....you're altering which cylinder is on a compression or exhaust stroke.....or an intake or power stroke....

[EricF]

I am going to try to be more tactful, but it is hard………


Originally posted by sport

The 351W "1,3,7...." firing order more evenly distributes the firing load on the mains. The old 289/302 with its "1,5,4..." order had the #1 and #5 cylinders firing one after another on the front main which was double stressing the weakest part of the block. Not a good situation, so Ford revised it back in '69 when they created the 351W.

If you trace the firing orders out on paper, you'll notice how the 1,3,7.. order puts the stress on the center 3 main webs taking it off the front where the block is weaker.

Lets create a Scenario

Engine is spinning at 6000 RPM

Which is 100 revolutions per second

It takes 2 complete revolutions for all 8 cylinders to fire, a cylinder fires every 90 deg.

Ergo, when a Ford 351W is spinning @ 6000 RPM each cylinder fires 50 times per second

50 times per second * 8 cylinders = 400 cylinders firing per second

This means that the time interval between each cylinder firing, at 6000 RPM, is .0025 seconds.

So with the 1,5,4,2.… firing order, cylinder 1 fires, then .0025 seconds later, cylinder 5 fires.

With the 1,3,7,2,6,5.….. Firing order, cylinder 1 fires, then .0125 seconds later, cylinder 5 fires.

With either firing order, there is still a pause between each cylinder firing, and cylinder 5 will eventually fire after cylinder 1.

So you are saying that the extra .010 seconds that the front main gets to “rest” before cylinder 5 fires, with the 1,3,7,2.… firing order, over the 1,5,4... Firing order, is going to make a difference with the fatigue of the front main in your “not a good situation” scenario?

Or what about a twin V configuration? For that matter, Is that also “not a good situation”


Good Lord, where do you come up with this stuff? Seriously, did you just make this up? Or after you “sketched out the firing order on a piece of paper” the entire cyclical stress dynamics of the rotating mass just came to you?

When an engineer what’s to analyze cyclical stress failures, they should just throw away all of their S/N curves & finite element analysis & just hire you instead, you could sketch it out on a piece of paper & figure it out, without going through any of that engineering nonsense no less.

Do you have any data that shows a difference between the high cycle fatigue of the front main by varying between the two firing orders?

[ChrisForbes]

Glad I don't have stock in that company. Great bedside manner. Dial it back a little more would ya.

The only way you could earn less respect is to talk longer.

[GeorgiaSnake]

Sounds to me like EricF knows of what he speaks. Ignore the puffed up chest and see if he will share his knowledge, we can all learn.

Out of curiosity how many firing orders can you have with a given engine? It's early morning and I can't seem to grasp the concept of willy-nilly changing of firing orders.

Randy

No need to yell I can hear just fine

[sharpe 1]

I think the firing order was changed because Ford had a new better idea.