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Ross .... interested in your long rod mill ... any thing you care to reveal ??

June 18 2017 at 7:41 PM
winr1  (Login winr1)
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Also, I cant find the link/s to the long rod discussion

Was there actually a long rod physically like a short rod ??



Ricky.

 
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Ross
(Login Bad427stang)
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Just a bench build

June 18 2017, 8:19 PM 

Using a bunch of leftover parts to build something that won't have enough head to be real fast, but should be fun to play with.

- .030 over 390, square decked
- 427 $ crank
- Diamond pistons with metric rings, 1.73 CH and 3.2 cc reliefs, zero deck, 10.22:1 compression, 1020 gaskets
- low mile set of 360 rods, (so not real long, just longer LOL) resized and ARP bolts
- Streetmaster with the Edelbrock mods, also have a P-sonic, but I think the small motor will like the torque of the SM
- Crappy set of C8AE-H heads with Alex's 2.09/1.67 valves and some mild work done
- Decent springs and titanium retainers
- Comp 280H intake lobe, 284H exhaust, 112 LSA on 106
- factory rockers, and new shafts, Dougs end stands
- Will start with a 600 Holley because I have one on the shelf, will play with a 1000 HP, but will likely end up with a 3310

Just going to play with it in my truck for a bit, see how it does and who knows what next. Likely keep as a spare or sell. Would love to see the build with more head, but this one is just a fun experiment
[linked image]
---------------------------------
- 70 Fastback Mustang, 489 cid FE, Victor, SEFI, TKO-600 5 speed, 4.11 9 inch.
- 71 F100 shortbed 4x4, 445 cid FE, headers, RPM intake, 1000 HP series Holley, 4 speed

 
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Bob
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Long rods........

June 19 2017, 4:15 AM 

Not to rain on any parade, but I copied over R-M's thoughts on long rod engines as an FYI:

"I'm sure Darin Morgan will comment on this.They have a lot of experience with testing different rod lengths. Here's a quote from Reher-Morrison's site from David Reher and his thoughts on the subject".

" We also wanted to point out some of the common myths and misconceptions about high-performance motors. For example, I've seen dozens of magazine articles on supposedly "magic" connecting rod ratios. If you believe these stories, you would think that the ratio of the connecting rod length to the crankshaft stroke is vitally important to performance. Well, in my view, the most important thing about a connecting rod is whether or not the bolts are torqued!

If I had to make a list of the ten most important specifications in a racing engine, connecting rod length would rank about fiftieth. Back in the days when Buddy Morrison and I built dozens of small-block Modified motors, we earnestly believed that an engine needed a 1.9:1 rod/stroke ratio. Today every Pro Stock team uses blocks with super-short deck heights, and we couldn't care less about the rod ratio. A short deck height improves the alignment between the intake manifold runners and the cylinder head intake ports, and helps to stabilize the valvetrain. These are much more important considerations than the rod-to-stroke ratio. There's no magic - a rod's function is to connect the piston to the crankshaft. Period."

This is located in the tech article "by the book" if anyone else wants to read the whole thing. Hope Darin does comment on this, he has some deeper thoughts on this with a GM backed test to back them up.
Shawn


    
This message has been edited by machoneman on Jun 19, 2017 4:15 AM


 
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Blair Patrick
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The difference Ross is working with....

June 19 2017, 5:25 AM 

is insignificant. However, you have to be careful quoting Pro Stock and Comp experts and applying it to every case. There is absolutely a relationship between rod length and port cross-section. Speaking solely on rod ratio, I agree that the rod ratio is usually not a factor. Keep in mind that those guys used very thick blocks.....a short rod can load a thin cylinder and cause problems that they never saw. Lots of things to consider when engineering a combo. There are only a few things that I write in stone, and rod length can effect things. Rod ratio being one of many things. I would bet that a 3.5 stroked FE in a thin 352 will run LONGER with a 6.7 rod and a stable, full skirt piston than it would with a 4.375 stroke and a 6.625 rod with a short piston. You gotta read between the lines and pick your poison a little bit based on what you are trying to accomplish. I think Ross used the rods because he had them, and called them "long rods" in reference to their being 6.540 rather than 6.490. That difference would be unmeasurable with everything else a constant.
Blair Patrick

 
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Randy
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I agree with Blair...

June 19 2017, 8:08 AM 

A rod length change of .050 is virtually no change in a rod "around" 6 and a half inches. I look at three factors, cubic inches , cylinder head capability , and rpm band. Small cubic inches and "giant" heads perform better with shorter rods and vice versa giant cubic inches with poor heads favor long rods. I also agree taking a comment about a Pro Stock engine out of context is a bad thing same as Smokey Yunick's famous "longest rod possible" quote. Another myth is "dwell" helping performance. Dwell is a point where there is NO MOTION. Last time I checked a reciprocating engine relied on motion to produce power.

 
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Ross
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Blair is 100% correct

June 19 2017, 2:37 PM 

No magic here, and can't rain on my parade LOL, just a nice little blueprinted 396 with parts I had available. Only way this one would be bad is if somoone stole the parts...

Really only benefit I see is a good build, zero deck, a little better ring pack, and pistons/pins that are "sorta" light at 125 grams or so less than stockers.

No "long rod magic" it'll be a 1.730:1 rod ratio with the 6.54 vs 1.716:1 for a 6.49 rod.
[linked image]
---------------------------------
- 70 Fastback Mustang, 489 cid FE, Victor, SEFI, TKO-600 5 speed, 4.11 9 inch.
- 71 F100 shortbed 4x4, 445 cid FE, headers, RPM intake, 1000 HP series Holley, 4 speed


    
This message has been edited by Bad427stang on Jun 19, 2017 2:51 PM


 
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Bill Ballinger
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I agree with Blair too. 3.78 stroke and 6.75-6.8 rods with light pistons and modern rings

June 24 2017, 3:13 PM 

short and light to throw around will really be kind to a thin 390 block where at say 4.155 bores leave you with .230 on the thrust side and .180 non thrust and .120 in between, because of less side loading. That all I want. I have triple web 105 block I hope can do it, at least to 4,125 and a 3.98 stroke, with those BBMs. The 394 is still damn stout, but 6500-7000 rpms with stock rods and fat rings is rattlesnake wrangling. LOL!

 
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Falcon67
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Good explanation

June 19 2017, 6:07 AM 

Also a good article to post if you'd like to flame up one of the Internet Xperts on engine building.

 
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Chris McAlpine
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From A Repair Shop Point Of View

June 19 2017, 8:28 AM 

Unrelated to the original post or Ross's built:
I have never ran a legal race or built an 10,000 rpm engine. From what I have seen in the everyday repair industry the short rod long stroke engines like some Chryslers and the Chevrolet 454 they tend to have more long term cylinder wear. If I remember correctly a late model stock 454 will be rev limited to 4,400 rpms. I looked it up once and I believe the engines mentioned had a 1.7 and less N value however brought there power in lower. The 1.75 N value a 390 has is considered premium. A 390 will run forever with worn out cylinders and not a lot of piston skirt distortion compared to some others with higher piston speeds between tdc to 45° to abdc........

 
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Mike U.
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I will add to what Chris said. Back when the first Ford mod motors came out they had like

June 21 2017, 3:33 PM 

IIRC, the first mod motors to come out had something like a 1.9:1 P/R ratio.

Those engines in Crown Vics used as taxi's racked up super high miles with minimal engine failures. [IIRC, too lazy to look it up, but those Crown Vic taxi's would usually see over 300k before being retired].

 
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Tommy-T
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Interesting!

June 19 2017, 9:31 AM 

Just curious,

How did you end up with a high-digit crank 'n pistons on your junk-pile? Seems an odd mix of high 'n low end stuff.

I've done a few of the same "long rod" 390's, a few with milled L2291's but mostly with rebuilder cast pistons.

So...is your 445 motor going on the junk-pile now?

 
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Bill Ballinger
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I was wondering too, is the 445 OK Ross?

June 19 2017, 11:12 AM 

Left overs sometimes taste better when you reheat them LOL.

 
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Ross
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I just want to keep the truck mobile

June 19 2017, 2:41 PM 

The parts were from a bunch of horse trading and some left over from the original 427.

I have enough work on weekends that an engine swap keeps the truck able to go to my storage building and I can keep a little dough coming in. I don't get rich from weekend work, but it sure does help feed the toys.

The 445 isn't broken, but continues to have a noise and will go back in when I figure it out. Then I will likely sell this one, heads aren't the greatest, but a high quality 396 short block will move pretty quickly around my parts

The 445 almost has to be a piston, and it runs like a champ, and won't blow up LOL, but who knows I may not hurry to get it back in once this one is running. It's likely going to be well over 100 hp difference though, so I am sure it's going to change the personality of the truck back to a truck LOL

I really really like the 445, when I figure out the noise, it'll be hard not to swing it back in.
[linked image]
---------------------------------
- 70 Fastback Mustang, 489 cid FE, Victor, SEFI, TKO-600 5 speed, 4.11 9 inch.
- 71 F100 shortbed 4x4, 445 cid FE, headers, RPM intake, 1000 HP series Holley, 4 speed


    
This message has been edited by Bad427stang on Jun 19, 2017 2:54 PM


 
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FElony
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Devil's Advocate

June 19 2017, 9:49 AM 

In the 90's I used to buy a lot of Mopar magazines in addition to the Ford stuff. There was a long and detailed article back then in one of them (might have been a "newstand special") about the benefits of a longer rod written by actual Chrysler engineers. Now, I know they are not Ford guys, but such persons have always had a good reputation for engine science.

I'm sure I still have that mag somewhere, but just now I did find a web page that "appears" to me to have been lifted from that article. http://victorylibrary.com/mopar/rod-tech-c.htm Does anybody see any flaws in the science or reasoning here?
====

 
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Cammerfe
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Some years ago....

June 19 2017, 10:18 AM 

it was thought that splayed valves were of massive benefit. This was based on the supposed superiority of the 'rat' motor and the supremacy of the Boss 302 over the 302 chibrolay in road racing. One of the chib-biased magazines set out to destroy that 'myth' by anonymously buying a pair of Trans-Am crate engines from Kalifornia dealers---one Ford and one GM. They supposedly treated both engines exactly the same on a dyno, including using the same pair of Holleys for both tests. The Ford came out 'winner'---but only by several horsepower.

But when they chased 'superiority' for another couple of months and attempted to do the same things to 'improve' both engines, the little Ford ran away and ended up putting out about 100 horsepower more than the chib. They attempted to save face by claiming that the Boss engine was simply a smaller copy of the 'rat'. And there was massive 'science' to back-up the supposed superiority of splayed valves.

A quick look at today's NASCAR engines will show that the scientifically-proven superiority of splayed valves has fallen by the wayside. Practicality reigns and the valve stems are parallel. And the engines put out several hundred horsepower more than they did during the Trans-Am period. Other things have been proven to be of greater importance than the valve stem angles to each other.

I believe the same things can be said about minor differences in rod length.

KS

 
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winr1
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Thanks Ross and others :-) .... N/M

June 19 2017, 11:10 AM 

Ricky.

 
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Mario428
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What parallel valves

June 19 2017, 4:01 PM 

https://performanceparts.ford.com/images/part/full/M-6049-E1.jpg

Specs
Fits NASCAR Engine Block M-6010-R500
Features:

Lightweight A356-T6 aluminum casting
Cross flow cooling
Internal oil passages for valvetrain lubrication
Splayed and canted intake valves
Five bolt head bolt pattern

Specifications:

Intake valve angle: 11.0� x 4.0�
Exhaust valve angle: 7.5� x 0�


Text is messed up but note valves have 2 angles.
Splayed valves will always be the answer.
Formula 1 uses tapered camshaft lobes to allow for splayed valves


    
This message has been edited by Mario428 on Jun 19, 2017 4:03 PM


 
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Cammerfe
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My point is that....

June 19 2017, 6:09 PM 

both the rat and the Boss have easily observable multiple angles. That sort of layout was thought to be a very significant source of power. Over the length of a valve stem, how much non-parallelness is observable with the current NASCAR engine(s)? Hopefully you take my meaning. I DO bow to your superior knowledge.happy.gif

KS

 
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Chris McAlpine
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That Is Yhe Article I Found A Few Years Back, Glad You Posted It nm

June 19 2017, 1:44 PM 


 
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I think the jist of it is
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Re: Ross .... interested in your long rod mill ... any thing you care to reveal ??

June 19 2017, 1:26 PM 

Will a short Rod or Long Rod both work yes. But what it comes down to is piston stability in the long-term. If you built two engines identical one with the short rod and one with the Long rod at 50 or 80 or 100 thousand miles the cylinder wear difference would be considerable.

 
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