Eaton Pulley Combo Reference

[mosconiac]

EDIT: The chart in this post has been updated. See post#16 for a more recent version.

A while back, I found a spreadsheet designed by "Slow Lane" that predicted a number of parameters given a pulley combination on an Eaton. I expanded on it and formatted the results into the following image. I did this in response to seeing a number of threads discussing how specific upper pulleys correlate to specific lower pulleys and what lower to combine with existings upper to acheive a certain boost level.

The following shows how each pulley combination stacks up relative to another. The pulley combos are ranked from top to bottom according to how fast they twist the Eaton.

Estimated boost is direct from the spreadsheet and I take no responsibility for accuracy. Debating their accuracy is pointless since variables such as temperature, humidity, and degree of belt slip will all play a role anyway.

Enjoy!

EDIT: I should mention that the pulley diameters may differ from the original spreadsheet. I inserted the numbers I got directly from Ron Kincaid (Metco), so the above is valid for Metco lower kits only. Also, "redline" = 6500 rpm.

 

[50 BMG]

:thumbsup: :rockon: :thumbsup: :rockon: :thumbsup:

Bravo.

Let me be the first to nominate this for a sticky.

 

[lthlsnake]

Thanks

awesome thanks again :bowdown:

 

[NHRACobra]

That is excellent. :thumbsup: Thanks much! :beer:

 

[DKS2814V]

sticky sticky sticky!!!

 

[gregs 03 cobra]

Now if we could figure out belt lenghts to match that would be the Eaton's for dummies!

 

[mosconiac]

Now if we could figure out belt lenghts to match that would be the Eaton's for dummies!

I've thought of that too, but with all of the combinations of upper/lower pulleys, idler pulleys, and alternator pulleys....WOW!

Another caveat about the boost predictions above is it will all depend on exhaust choice, whether the blower is ported or not, what cams are installed, what atmospheric conditions are present....

 

[50 BMG]

Understood, but it's a great place to start your referencing from.

 

[Seabiscuit]

What is the max rotation of our eaton supposed to be?

 

[StangJason]

I've read where the stock pulley only makes around 6-8 psi but I will admit that my boost gauge is pegged out to the first line before the read though so it seems to be a bit more than 6psi.

 

[pj_rage]

Since I have installed my lunar boost gauge, on the stock eaton the most boost I have seen is 7# Of course, as mosconiac says this can vary alot. From the chart it looks like the stock RPM of the eaton at redline is 13534rpm. I didn't realize how much it gets overdriven with smaller pulleys. I mean I knew it was overdriven, but not 33% and in some peoples cases, almost 50% Are we asking for it in the long run? (i.e. after running the 2.76 for 50,000mi+, is my eaton a goner?) I know it has been discussed that it is pretty much ok, but in the long run, this must do something, right? :shrug:

 

[Seabiscuit]

What is the max rotation of our eaton supposed to be?

Just trying to find out what the max allowable RPM the Eaton is rated at? I had heard somewhere that the max was 15500 rpm at 6500 for our engines. Hopefully someone can verify this.

 

[Brannon]

Nice chart.

 

[stangd1909]

very nice

 

[50 BMG]

ttt, someone needs to sticky this thing.

 

[mosconiac]

Slow Lane updated his spreadsheet, so I revised the summary I based off it. This change gives better boost estimates IMO.

 

[whistlin93SVT]

Now if we could figure out belt lenghts to match that would be the Eaton's for dummies!

Cobra Bobs website!! For belt selection.

http://stangshiftergaskets.com/BeltSelectionGuide.htm

 

[IronTerp]

Significant differences from original chart. Mosconiac, maybe you should edit your original post if you feel this second chart is more accurate.

 

[Yellow cobra]

Thanks a lot

put i think the EATON will blow up with 2.8 pulley :burn:

what do thing?

 

[ITSTOCK]

Some of those figures STILL seem off to ME. With the 2.76 I usually see upper 13's, almost 14's, unless it's like 20degrees out.

Elevation+temp. play a decent part in how much boost you will actually see.

In 50-80* weather here (Horsham, PA, about 100' above sea level, good DA), the 2.93 only gives lower 12#'s of boost.