80/20 Rule

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273

273

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I brought up they 80/20 rule in another thread, I think it what causes a lot of friction on here a lot of the times, I feel for about 80% of people are looking to gain 80% of available power with 20% effort. Eg. good running 318 add mild generic cam 4bbl and duals and tune and call it a day but for other 20% of us we see the wasted 20% of potential left. And even that last 20% potential left 80% of the other 20% are only willing to do 20% to get 80% of that last 20% and on and on. lol

Got to remember also 80% probably know near zero about cams, 20% can do the job themselves and on and on.

Any thoughts ?
 
I’m always a fan of “the most...... for the least”.

The most gain, with the least effort.

Goes for porting too.

Actually...... especially porting. ;)
 
Here is my list of questions to your question :)
  • Is it really 20% left on the table? How do we know?
  • Whatever the % that IS left on the table, what's it cost to get it????
  • Whatever the cost is to achieve that last % number, what if we spent it on another part(s) to increase more power be worth more power than the money spent to get the last % of power left on the table?
 
I am 20% sure that your 80/20 rule is about 80% off.

:poke:

Joking aside, many folks go off on a wild building spree when it isn't their money and labor. If they got to experience the need for ibuprofen for every build that is discussed and the pain to the checking account, then they would not be so eager to maximize every cruiser build for racing or mud bogging or tractor pulls.

Just my 2 cents.
 
IMO the 80/20 rule applies to a whole lot of things in life. Before I was even aware
of this concept I applied it most aspects of daily work life with mostly good results. The problem I faced was dealing with all in 100% type of people who do not like or understand this philosophy.
 
318willrun said:
Here is my list of questions to your question :)
  • Is it really 20% left on the table? How do we know?
  • Whatever the % that IS left on the table, what's it cost to get it????
  • Whatever the cost is to achieve that last % number, what if we spent it on another part(s) to increase more power be worth more power than the money spent to get the last % of power left on the table?
Click to expand...


the 80/20 rule is general could be 70/30, 90/10 or anything really it's just an philosophy, say you got a stock 4bbl 360 with a Holley for tuning and headers. what do you think is the maximum you could get out of it with just cam, if you were a cam manufacture any willing to put crazy money and time at it. There's got to be a limit. Say it's 400 hp, think you could get 80% or more with off the shelf cam ? Also say a common choose cam, xe 268 gets 330 hp do you think a mild 205 @ .050" .425 lift could get you 80% or there etc..
 
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I think those that offer a service, per say a machine shop, then they want to do a "100 percenter" on your stuff. I don't think money is the main reason either. I think it's because they want to remove all risk for their shop names sake. But when these 100%er's take their shop truck to the body shop for a quick coat of paint to make "the ole girl look a little better", I bet they won't agree for a Full Frame Off Restoration ... :D Funny how it is when it's turned around :)
 
273 said:
the 80/20 rule is general could be 70/30, 90/10 or anything really it's just an idea, say you got a stock 4bbl 360 with a Holley for tuning and headers. what do you think is the maximum you could get out of it with just cam, if you were a cam manufacture any willing to put crazy money and time at it. There's got to be a limit. Say it's 400 hp, think you could get 80% or more with off the shelf cam ? Also say a common choose cam, xe 268 gets 330 hp do you think a mild 205 @ .050" .425 lift could get you 80% or there etc..
Click to expand...
There is no way of knowing unless a back-to-back comparison is done. HOWEVER, I would rather have 80% of the correct part tuned 100%, than have 100% of the correct part tuned 80% :)
 
To me, most people that want the right combo off the bat are better off with something slightly milder than what they think they want, now if your willing to play with a few cams and gears and carbs etc.. you can dial in your combo then go wild, it's hard to know where you want to go if you got no reference point. I don't get a lot of, I got a /6 car and want a 500 hp 318 that never had years experience with modding engines, how about start with a stock magnum and do little improvements over time, so you can get a better grasp over time on what you want.
 
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The 80/20 rule is probably pretty accurate. I'm probably in the 20 part. Even if I doing low buck bang for the buck type stuff (not just cars) I want to get all the bang for the buck. Every car I've owned out side daily drivers I've tried to get everything that was available out of them.

For years I shot a bow and I worked hard at it to be the best I could be at it. Not necessarily to be better than other people but to be my best. To get everything that was there.
 
Maybe that 20% requires smarts and thinking and most people are too lazy to do that.
 
I find that at this point in my life 80% of my patience is gone, and the remaining 20% is getting pretty thin, however I still want to get 80% more for less than 20% of the effort that I used to have to put in.:poke:
 
The 20/80 rule is that 20% of the people do 80% of the work. I can measure and have tried all kinds of combinations on all kinds of engines. I know what I can get away with and what not to even bother with. Try my best to give the customer what he wants. Just don't even think of rushing me. Not sure where that leaves me.
 
66fs said:
Just don't even think of rushing me. Not sure where that leaves me.
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I'm much the same, if I take on a customer side job, which is pretty rare these days, since I work 45 hours a week at my job, it's only on my terms, don't like it, go somewhere else, I don't need the money, nor do I need to do anyone a favor. It'll be done when it's done, don't call me, I'll call you.
 
I like to brainstorm first

First: Compression ratio

Second: Camshaft selection, advance or retard

Third: Rear gear/tire height, which works with camshaft

Fourth: Carburetor

Fifth:Exhaust

Sixth: timing and distributor curving then carb jet and rods combo which works best.

And somewhere in there a shift kit if it's an auto and some Advil.
 
318willrun said:
There is no way of knowing unless a back-to-back comparison is done. HOWEVER, I would rather have 80% of the correct part tuned 100%, than have 100% of the correct part tuned 80% :)
Click to expand...


When you do it long enough you have a good idea what you’re leaving on the table. I’d bet PRH, RAMM...replicar...I know there are more can give you a razor close estimate of what left on the bone.
 
318willrun said:
  • Whatever the cost is to achieve that last % number, what if we spent it on another part(s) to increase more power be worth more power than the money spent to get the last % of power left on the table?
Click to expand...

If the average guy comes up a few hp short on a build then what another similar guy did you might rob yourself a few 10th in the quarter mile.
In things like F1, Nascar etc.. those little gains are the difference of winner/loser that's why so much R&D, no average guy can go in Nascar like they could in the sixies.

I our local stock car racing their drives that grabbed rockers of every Chevy they could find for best set they could put together, it's all these little things that added up.
 
yellow rose said:
When you do it long enough you have a good idea what you’re leaving on the table. I’d bet PRH, RAMM...replicar...I know there are more can give you a razor close estimate of what left on the bone.
Click to expand...
Are you sure??? It was like pulling teeth in a alligator to get the simplest answer on what lifter should I buy for the Lunati 703 cam..... :poke::poke:
:lol:
 
318willrun said:
There is no way of knowing unless a back-to-back comparison is done. HOWEVER, I would rather have 80% of the correct part tuned 100%, than have 100% of the correct part tuned 80% :)
Click to expand...


LOL...should have read this closer. You can go to any track and see 98% of the people with 100% leaving way more tune on the table than anything else.

I know there are people that can’t even correctly use a timing light. And I won’t even start on the junk chassis and silly tuning you see at the track.

But they have all the polished ****, with the toter home and all the bells and whistles and the car is .2 slower than it MPH. You look at the chassis and not only does it have cheap shocks, it’s over sprung, severely travel limited and the guy says “the track is absolute ****...I can’t get it hooked...” and you walk away, shaking your head and say with all that tire it ought to hook in a car wash.
 
yellow rose said:
When you do it long enough you have a good idea what you’re leaving on the table. I’d bet PRH, RAMM...replicar...I know there are more can give you a razor close estimate of what left on the bone.
Click to expand...

273 said:
If the average guy comes up a few hp short on a build then what another similar guy did you might rob yourself a few 10th in the quarter mile.
In things like F1, Nascar etc.. those little gains are the difference of winner/loser that's why so much R&D, no average guy can go in Nascar like they could in the sixies.

I our local stock car racing their drives that grabbed rockers of every Chevy they could find for best set they could put together, it's all these little things that added up.
Click to expand...
So I will just say this, and I'm not disrespecting anyone!!!. I did a "guess my ET" thread when my basically stock 360 had stock exhaust manifolds, stock 904/converter and 2.45 gears. NOT A SINGLE ONE guessed 13.9's. Nope, not one. Not even me. All guessed 15's and 16's except for 2 guys - me and another guessed 14's. When it comes down to it, I'm not sure I believe in the word "guru" or if anyone has a ripp'n clue vs another.
 
66fs said:
The 20/80 rule is that 20% of the people do 80% of the work. I can measure and have tried all kinds of combinations on all kinds of engines. I know what I can get away with and what not to even bother with. Try my best to give the customer what he wants. Just don't even think of rushing me. Not sure where that leaves me.
Click to expand...


DING DING DING...NAILED IT.

Which is why I don’t join clubs, committees, focus groups or anything else. Way too many lazy people.
 
318willrun said:
Here is my list of questions to your question :)
  • Is it really 20% left on the table? How do we know?
  • Whatever the % that IS left on the table, what's it cost to get it????
  • Whatever the cost is to achieve that last % number, what if we spent it on another part(s) to increase more power be worth more power than the money spent to get the last % of power left on the table?
Click to expand...
When this came up in the other thread which has a title about "performance" I defined how much is left on the table in percentage of maximum.
So if there is 5 hp gain on a 250 hp engine, that's roughly 2%.
5 hp on 250 hp is pretty doable with a jet change because that is measurable with some degree of confidence on a chassis dyno. It's also measureable as mph at the track although somewhat more subtle depending conditions and consistancy.

I'm not sure about 20% but I will go with 5-10% of WOT power is often left on the table after spending the time and money with engine mods or bolt on.
(If its off more than that, it probably doesn't run well at all.)

In this post I pointed out how much power can be gained by testing jet changes. Not just peak, either.
These runs were made on the same day on the same chassis dyno.
70,74 to 66, 72
upload_2020-2-19_21-7-2-png.png


Lets call it 11 hp gain on 267 or 4% improvement in power for 5 runs.
or we could say its a change of 8% in fueling. LOL

Was there much more in there? Not alot. Runs 13 and 14 were very similar and we can see the main air bleed relationship to the jets was beginning to get lost. So at that point it gets into a bit more time and knowledge. I'll actually be reinstalling that carb this summer, so yea I'm in that 20% or 5%
laugh2-gif.gif
 
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