Disaster waiting to happen or facial falgellation

[Dbl G]

O.K.

4# lower
2.93 Upper
K&N FIPK
Brisk Plugs
Diablo Tune from RWTD

1.84 Pres.
8.5 LP
2.93 UP
2.7 ED
14.7 PSI
______________
14.36 Boost

I used Cayman150's Excel boost chart and this put's me at 14.36 on the booster seat or is it a ejector seat to the engine re-builder. I believe I may get a on site tune however from Tim Matherly @ MV Performance.

[jwhite]

you'll be fine...
just let RWTD do his job...he has tuned mine and i am at 14-15lbs boost at WOT, a/f = 11.9-12.0
15*-16* timing and can hear no detonation.
422rwhp & 48x torque and runs like a raped ape!

just keep a keen ear for detonation, and if it presents itself, get out of the throttle and add some fuel with your predator and you'll be fine!

James' tunes are usually right on the money...at most, you might have to richen the fuel 2%-5%, but more than likely, you wont have to do anything!

[Dbl G]

He was real close on the first tune, pinged on the second pull and he sent me another tune the next buss. day.
Just nervous I suppose, $200 or $5,000 for a block and goodies. 14 boost and change is there, right there, boost wise...I feel comfortable with James, it is just so close,,,,Dammmmmm

[jwhite]

many people have ran 15+ lbs of boost on their stock bottoms without any problem...true most blown engines are a result of too much boost, but there are other factors involved also (like bad fuel, bad tune, cold weather etc...)

i'm sure his second tune will be next to perfect.
just for added measure, take your truck to your trusted muffler shop and ask them to weld an o2 bung on your drivers side down pipe about 3 inches before the first cat at about a 30 degree angle above center pointing up.. if they have an old o2 sensor lying around (which im sure they would) ask them if you can plug it with that...
should cost you only about $40 or so.
then when you go to the dyno, you can have the dyno place use their wideband to read your a/f instead of the tailpipe sniffer...might not be that much difference, but reading it with the wideband will be the most accurate.
if you are lean, just add some fuel using your predator...3% more fuel, then re-dyno...repeat as needed.

[Dbl G]

The first time they used a wideband...

[jwhite]

ooooooook,
i'll stop posting then and just say
good luck

[MRBLUEOVAL]

I am safely running 15 lbs boost at around 11.8-12 A/F and I have all sorts of goodies to go with it. The key is a good dyno tune. Too lean will blow you up. Boost is not necessarily what causes a blown motor. Anything parst 15lbs on a stock Eaton is just creating heat and no gains at all. This is a fact. I would be anyone who wants to try on a dyno. The stock Eaton will just create a ton of heat and due to restrictions the speeding of the blower or boost just causes heat and this will hurt your motor as well by causing the lean condition. I'm right around 425 at the wheels and still have my ported blower and plenum to put on! I look forward to it. I will probably go from an 8lber to a 6lber though because I'll gain effiecency and this will allow more air to flow at a cooler temp creating the extra ponies and torque we all love

[Tazz]

If you really want to get technical when you spin the stock M112 above 6K you start creating heat above the 100 degree mark from the outlet of the sc and just starts to climb from there. Once your in about 10psi of boost and spinning the blower at 14K your around 250 degrees from the outlet of the sc.
So when your at 15psi and spinning the blower at 14K your probably near 350++ at the outlet and really probably closer to 400 degrees. Now thats HOT.
Tazz

[hemiuk]

way over my head ?

[Dbl G]

Tazz, I had tought about taking some temp reading's on the SC and front snout area. I have some more goodies for next week, mentioned above.....

[Tazz]

Just hammering home the fact that the Eaton starts to fall off in efficiency when pushed past 6K rpms and gets worse from there. In stock form the HD spins the eaton at a max of 12,300rpms which is way past the 6K mark. You add larger lowers and/or smaller uppers in conjunction with raised rpm limits that most have over stock and your really over working the Eaton and not producing any real usable power unless there is some way you can cool the outlet air charge down at 14-15psi of boost. Now the inner cooler does cool down the air charge but once you push the stock inner cooler and heat exchanger to cool down a 400 degree air charge it really becomes pointless and cannot do this effectively.
Tazz

[Dbl G]

So add in a larger inter-cooler radiator/ additional exterior radiator for the inter-cooler and larger reservoir, also focus on other HP gains, fan's, electric water pump, intake systems, water wetter, etc.. Little thing's add up..