Feeler- D.I.Y. Eaton M62 Supercharger Kit

[CobraMarty]

Is the M62 Eaton Supercharger 'big' enough for the Jeep 4.0L?

Right from Eaton's webpage-
"The Eaton Supercharger Model 62 is designed for 2.5L to 4.0L passenger car and light truck engines, but may also be suitable for other engine sizes, depending on total system performance requirements."

A few basic facts about the M62 supercharger
Each revolution of the supercharger puts out 62ci (cubic inches)
Maximum rpm is 14,000

Using the Jeeps stock balancer/pulley which is 6.0" diameter and a 2.25" supercharger pulley you get 2.66:1 pulley step-up ratio.
2.66 x 4850rpm(shift point of AW4) = 12,933 supercharger rpm, well below the 14,000rpm limit.

2.66 x 62ci x 2 (2crank rotations for one engine cycle) = 325ci/1engine cycle.
325ci of s/c air into a 242ci engine = 1.34 = 34% more air than a theoretical 4.0L engine needs.
34% x 14.7 (pounds of 1 atm) = 5.04 pounds

Because the Jeep has such a poor flowing head and minimum cam such that it can't even 'inhale' the full 242ci of air, the % more air is even higher,

So the Eaton M62 Supercharger as pulleyed above will easily provide between 5.5-6 pounds of boost, which is just a little more than the 'theoretical' potential of 5.04 pounds.

 

[urban yan]

thanks for the cut and paste. We all know what "to 4.0L" means.... it means the M62 is pushing its upper most limits. By contrast, M90s are rated for displacements from 3.0 - 5.0L, they don't even cost much more than M62s (used).

In any case, I wish you luck with your project; I hope it works out just as well as your 2 projector Chinese projector set-up.

 

[CobraMarty]

Still 'slammin' yan. The math explains what you don't understand.

 

[Talyn]

Using the Jeeps stock balancer/pulley which is 6.0" diameter and a 2.25"

Its not 6.0"

2.66 x 62ci x 2 (2crank rotations for one engine cycle) = 325ci/1engine cycle.
325ci of s/c air into a 242ci engine = 1.34 = 34% more air than a theoretical 4.0L engine needs.
34% x 14.7 (pounds of 1 atm) = 5.04 pounds

Lol.. if it was just that simple to figure to figure it out. I see nothing in that equation taking in to account camshaft specs.

 

[CobraMarty]

That's all you have to contribute? not much.

 

[Talyn]

You clearly know it all, so what should I have to contribute? If you want to do calculations, at least get simple measurements correct. Your equation to figure boost simply does not work.

 

[CobraMarty]

obviously nothing to contribute.

Prove that the equation doesn't work. Can't? Didn't think so. Math will always work.

 

[urban yan]

That's all you have to contribute? not much.

obviously nothing to contribute.

Seriously dude. You have a rotten attitude.
We told you before that naxja isn't populated with yesmen, so stop getting hissy everytime someone competent – like talyn or ogs – disagrees with you.

 

[Talyn]

Prove that the equation doesn't work. Can't? Didn't think so. Math will always work.

Math will work to get you close, but that equation won't even come in the ball park. It does not take into consideration any camshaft events, which play a huge part in how much boost something will make. There is nothing to prove as anyone that can understand what role the camshaft plays will easily see that equation is not correct. Nor does it take into account any of the flow characteristics of anything on/in the engine (heads, intake, exhaust, etc). It also leaves out anything having to do with the super charger's efficiency.

Your numbers are wrong as is your math.

 

[CobraMarty]

Again no explaination. The cam will have the same effect as far as this is concerned on the engine n/a or supercharged. The best cam and maniflod and head flow- ie NASCAR territory will only give you slightly better than 100%VE, maybe 110%. They can stuff/suck 10% more air into a given displacement engine. The Jeep 4.0 is soo far from this that any cam will have a minimal effect on the flow into the engine. There is no way the Jeep 4.0 will ever get 4L of air into it no matter what head, cam or manifold is used, period.
Show us your math and take into acct cam numbers and pressure differentials and show how much boost and power will be made. I can back up all my math and equations and predictions with real world results. My math will get me alot closer than your internet learned knowledge.
You harass and bad mouth and back none of it up with facts, numbers, equations, formulas, or results.
What you are is very obvious here. Internet forum bully.

 

[Talyn]

Again no explaination.

The explanation is right there. It doesn't take into account anything about an engine.

The cam will have the same effect as far as this is concerned on the engine n/a or supercharged.

Not 100% right, but close enough. And once again your boost "formula" does not take into account anything other than the speed at which things are spinning and the displacement of the engine.

The best cam and maniflod and head flow- ie NASCAR territory

Napcar is a poor example. Too restricted by rules.

The Jeep 4.0 is soo far from this that any cam will have a minimal effect on the flow into the engine.

Really? That is just plain BS. The cam is what controls flow into the engine.

Show us your math and take into acct cam numbers and pressure differentials and show how much boost and power will be made.

There are equations that easily estimate power based on boost, but I don't know of one that is accurate on how much boost can be made using x supercharger on x engine with x cam, intake, exhaust, etc. Unlike you I am not putting out BS.

I can back up all my math and equations and predictions with real world results.

You can't back any of your crap up.

 

[Talyn]

Since you are so fond of meaningless equations, here is another inaccurate (based on actual cfm though, so more accurate than your garbage) equation to figure boost.

Crank Pulley diameter= 6.375"
S/C Pulley Circumferance = 2.25”
Ratio = 2.83:1

@ 4850 rpm = 13725 supercharger rpm (14716 @ Red line)

The M62 output = 1 Liter per rpm/ rpm (LPM*.03531 = CFM) = 484.6 CFM of air

The 4.0L engine's calculated CFM is 371, not that far off from a dyno measured 383 cfm

Boost air = 484.46 – 383 = 101.46 boost CFM

Boost = Boost CFM / 4.0L CFM * atm pressure
101.46 / 383 * 14.7 = 3.89 pounds boost

And once again that is not taking in to account pumping losses and the such, so likely even less.

 

[CobraMarty]

http://www.widman.biz/English/Calculators/CFM.html
one of many formula/calculators out there.

The 4.0L engine's calculated CFM is 371, not that far off from a dyno measured 383 cfm

Wow cowboy, that is way optimistic for a 190HP 242CID 4900rpm engine.
Try alot closer to 273cfm or less.

Using your hyperinflated 383 corrected for real 273 x 3.89 = 5.457 pounds boost.

That's what I have been saying, thanks for proving it again.

 

[Talyn]

I actually was in fact using the wrong equation to calc cfm. However, it was off only a little.
The correct equation is:

CFM= (rpm x displacement)/(2x 1728)
1728 = number of cubic inches in a cubic foot
CFM= (RPM x displacement)/3456

CFM=(5200 x 242)/3456
CFM=364.12

 

[CobraMarty]

I actually was in fact using the wrong equation to calc cfm

And again you are wrong. If you are going to play with numbers, formulas and equations, at least use the right ones. Just because someone has a calculator doesn't make them a mathematician. Be careful playing with numbers, it is like playing with matches, and you can hurt yourself.

The formula that you used is to predict the theroretical maximum air flow thru an air pump. 'displacement x rpm x conversion factor'. Wrong. This is in the perfect setting no intake or exhaust restrictions. This is the max 'potential' cfm under perfect/ideal conditions and 100%VE. The Jeep 4.0 engine is far from this.

We can measure the actual cfm ingested by the engine when on a dyno and special 'hats' to measure this directly but we don't have to. We know this indirectly by the actual HP made. There is a correlation/relationship between cfm and Hp and vice versa. We know that the jeep 4.0L engine produces 190HP and from that known number can calculate the actual CFM ingested. That is the number to use in formulas and calculation. In the case of the Jeep 4.0L, 273cfm is the more accurate number for this engine.

 

[Talyn]

All your calculations are theoretical. And 100% wrong. Face it, your chosen supercharger is too small. Go back to making some heavy plates for seats or whatever else it is you like to screw up.

 

[CobraMarty]

All your calculations are theoretical. And 100% wrong. Face it, your chosen supercharger is too small. Go back to making some heavy plates for seats or whatever else it is you like to screw up.

So when the M62 s/c makes 5-6 pounds of boost, how is that too small? Facts to back up your opinion only.

 

[urban yan]

The M62 is not optimal for the 4.0L. You can skew numbers any which way you can, but the fact remains that you're wrong. Why the heck would anyone spend money on a project that lacks any scalability, and is based off cut and paste research.

I swear, this thread parallels your bi-xenon project. You turned this forum upside down defending a failed set-up (which you tried to sell us too btw), and then you ended up replacing your headlights with something else because they were utterly useless.

 

[CobraMarty]

Lacks scalability? It is what it is, a 5-6 pound boost entry level supercharger system for the Jeep 4.0L engine.

As for the headlights, they worked fine, not 'utterly useless' and we did upgrade to LED headlights.

 

[urban yan]

HIDs produce 3200lumens, those replacement truck-lites produce ~1200 lumens (~1/3 less light); when installed, your son went on to say
”All I have to say is "WOW!!!". Honestly, I'm in love with them! I actually enjoy driving my Cherokee at night now!!!”

Nobody would say that unless their HID project was a complete and utter failure, but I’m sure you’ll try to lie your way out of that one just like you’re trying to lie your way out of this M62 project.

You have NO credibility here.