how much boost can stock eaton handle

[QIKPNY]

I am running a SF 2.80 upper with the 6lb Metco lower and running 17lbs up to 6100 then dropping to 15 to the top end. Car runs strong with that set up and all parameters looks safe.

My question is, how fast can we spin the Eatons after the port job?

 

[QIKPNY]

BTW...I'm currently in Myrtle Beach for Mustang Beach and will hopefully get to run the car through the 1/4 tonight at Darlington....if I get by tech with my vert (maybe they will think the styling bar is a roll bar ). In any case, if I get to run, I'll post my numbers to let you guys know what to expect from a set-up like mine.

Don

 

[florida03]

Originally posted by Vrrooom
More PSI shortens life by alot.

Also, the more boost you run on that little Heaton is going to create less efficient boost, not to mention make it extremely hot.

Ive heard of a few motors going south prob due to tune
but never read anything about the Eaton not holding up.
Your right about the heat but I feel if you run a 2.9 or
smaller alittle discresion goes a long way. :beer:

 

[RAZRS EDGE]

Originally posted by ALA G8R
The 3.1 is definitely not a waste. But the 2.93, too me, seems like the sweet spot for the M112 on my car. The 2.93 will not spin the M112 at 15500 rpm until the engine RPM exceeds 6150. How often are you running at redline?

M112 RPM = Engine RPM x Lower Pulley Dia. / Upper Pulley Dia.

What pulley/idler setup are you running?

 

[ALA G8R]

BilletFlow interchangeable system with a 2.93. I have a 4-piece BilletFlow idler system. Bottom and passenger side idlers are 92mm. Driver side and aux idler are 100mm. Uses stock belt.

 

[BANDIT HPT]

I went with a 2.93 pulley but I'm already considering the 2.73. I do drive the cobra everyday but I don't stay in the throttle alot. Very few times do I even get into the throttle enough for the factory boost guage to move. I look at the eaton as a gun. I only pull the trigger when I need it ; )

 

[Mo Boost]

Suggest you guys look at the tech info that Kenne Bell puts out on its website

http://www.kennebell.net

They have efficiency comparisons of the M112 Roots Eaton and their twin-screw models. They say spinning the M112 past 13-14lbs of boost actually produces higher intake manifold air temps. They have the test results to prove it posted on the site. Just look in the Lightning section detailing the test published in MM&FF....

The engine internals of an '03 Cobra are forged. The internals of my L are tough, but aren't of comparable quality. If I wanted to run past 13 lbs of boost (voiding my warranty), I would change the supercharger, pulleys, and get a short block replacement ...
Stock heads support only 2 valves/cylinder right now, but the Gen3 will have more valves (on a built bottom-end) if it ever hits production.

Then you guys will start wanting a 5.4 L engine in your Cobras
:coolman:

 

[BenD]

Life of the Eaton question, My experience

I have 10,300 miles on my '03 Coupe and just had the Eaton replaced with a new one. 7000 miles of that 10,300 was running a 2.80. The bearing in the nose got bad. I don't know if that answers your question.

 

[florida03]

Re: Life of the Eaton question, My experience

Originally posted by BenD
I have 10,300 miles on my '03 Coupe and just had the Eaton replaced with a new one. 7000 miles of that 10,300 was running a 2.80. The bearing in the nose got bad. I don't know if that answers your question.

Sucks you had a prob with your pullyed Eaton,
but ive been on this sight for almost two years and
if I can recall thats one of the first SC ive heard not
surviving.
No flame intended.:beer:

 

[MTI LS1]

If you pulley the car your taking a risk in the first place no matter how small you go. Honestly, I'm not worried about anything. I have a 2.75 upper with idlers and a kick ass tune. If something happens, the KB may be on sooner than I thought, but I'm not planning on it.

 

[Black2003Cobra]

I only made 4.3 more HP with the 2.93 compared to a 3.1. The bigger gain was in torque. I made 18 ft-lbs more torque w/ the 2.93 vs. the 3.1. So what I do, is just use the 2.93 for the track and run the 3.1 on the street. My thinking is, why overspin it and heat things up so much more just for 4 HP (in my case). With Doug's interchangable pulley, it only takes a couple of minutes to change it.

 

[FIRSTFORD]

Hey what about the Whipple bolt on?

 

[Kiddk1]

Originally posted by Black2003Cobra
I only made 4.3 more HP with the 2.93 compared to a 3.1. The bigger gain was in torque. I made 18 ft-lbs more torque w/ the 2.93 vs. the 3.1. So what I do, is just use the 2.93 for the track and run the 3.1 on the street. My thinking is, why overspin it and heat things up so much more just for 4 HP (in my case). With Doug's interchangable pulley, it only takes a couple of minutes to change it.

yes but when you change pulleys dont you have to adjust your tune each time?

 

[Black2003Cobra]

Originally posted by Kiddk1
yes but when you change pulleys dont you have to adjust your tune each time?

If you go with a Diablo Delta chip, with just a flip of a switch you can go from one tune to the other.

However, if you have a tune for a 2.93, you can "safely" run a 3.1. You just won't be running as much timing as you otherwise could be with the 3.1.

:thumbsup:

 

[Kiddk1]

thanks