In the latest issue of MuscleMustang & FastFord, with the help of JohnnyLightning, there is a test of the new Kenne Bell blower.

THEY GOT 522hp and 600ft lbs ON A STOCK BOTTOM END!!!

How did they do that and not blow it to the moon.

They were running 21pounds of boost in the final test!!!!

I dont understand. I was under the impression that 14 pounds of boost through the Eaton was pushing the limits of the stock internals

Someone please help me understand, 'cause I would sure like it if I can bolt on the Kenne Bell blower and not have to rebuild the bottom end (I know its just a dream)

Jason

 

I read that article today too. They dyno'd the truck but they don't give any short or long term results......No trips to the track or anything...I was wondering the same thing.......JR

 

The blown bottom end comes from over flowing the mass air and causing it to go to the full five volts. At this point the computer lookes to a set of look up tables that are based on full throttle/5400 rpm/and the assumed boost of 8 pounds it calculates the amount of fuel that must be required. At this point the asssumed 8 lbs of boost is a groose under estimate and the motor goes lean and into huge detonation and bang, the rods are the first to go.

Hope this helps

Andy

 

awhittle, Agreed! I've been away too long but I know this has been discussed. Do the tuners such as JDM have the capability to modify this table on a chip so this doesn't happen??? Boost alone will NOT blow a motor - especially one with a much more efficient KB blower .

 

Im sorry but two plus two is not equaling four here...

Even if your MAF/Detination theroy did hold true (which I will do some research about), the power alone will break something... We didn't go through two motors by maxing the MAF and causeing horrific detination... Pure power over time and stress did it...

I dont see that motor sticking together for too much longer.

 

I have said this before detonation and running lean will not cause the rods to break. It will however destroy sparkplugs and pistons. Eventualy to much boost will cause a rod faillier and reving it to high. I know first hand cause I have already destroyed one engine and I am building one up to handle about the 700HP I want to run through it. All my plugs and pistons that were still in one piece looked just fine and the plugs had a perfect tan color. The new Eaton blower would eventualy destroy the stock bottom end.

 

Things rarely "blow up" on the dyno because a dyno ( Dynojets specifically ) does not put a load on the motor like real world situations will.

 

OK that would make it all equal four... I still say that motor wont last 25 runs down the 1/4...

 

My apology on the wording of the post above

I should have started the wording:

I have been told by a well informed tuner that a common cause of the blown bottom ends is ....

This issue is more pronounced on the 01-02 computer. 99-00's seldem break a rod.

I would think that telltale signs on the pistons and plugs would help verify the real cause for the failure in question

It is true at these loads (rpm AND torque make HP) induce fatique on the rods. Someone will have to waist a few motors on the dyno to find out. It is far from a cheep experment.

Always asume that if some post comes up stating "I have beem running XYZ mod for 3 days/months/years and have not blown up...) They may be just lucky. You have to look at a larger sample to realy know. How many times have you heard someone say "My grandpa smoked for 60 years so smoking must be safe"

Hope this helps

Andy

 

Well for one, I've been JIPPED!! I haven't received my issue yet!

Another, if this is Johnny's motor, doesn't he have a built bottom end? Unfortunitely, I haven't read the article to know if it's Johnny's or not. I do know that he has one on his and was doing testing.

 

If all things are right, the bottom end will hold up. It's just when you get a bad tank of gas, temps change and the tune is too aggressive, fuel starvation, weak rod, etc.

I have reservations on the idea of the mass air flow maxing out.. I see 850hp cars in 5.0 magazine running 90mm MAF's that don't max out.

 

I’ll be clearer on this – RPM’s KILL a motor. Even a 500rpm increase from stock will do this! Tensile stresses in a rod increase by a squared function of rpm. The centrifugal force due to rpm is the critical load here. Increasing the rpm from 5400 to 5900, a 9% increase in rpm, increases the tensile stresses by over 23%. Do you think you have a 25% tensile margin in your rods?

Boost adds compressive stresses, which actually improve the fatigue capability of the rods. If you’re worried about higher boost levels, back the shift point rpm down a couple of hundred. Remember, HP is a function of torque and RPM. Leave it to the rice boys to get their HP from RPM. Their small mass motors can handle these loads. Let’s use the increased torque from boost to build our HP and keep the rpm down to keep the motors together. The area under the torque curve is what truly matters.

If you want to read more, Corky Bell has a couple of great books out that explain this extremely well without getting too technical. His classic is on turbocharging, and very similar information can be found in his new supercharging book Supercharged! Design, Testing and Installation of Supercharger Systems.

 

It has more to do with the 01,02 pcm than 90mm.

Mike

 

well...it does have something to do with maxing out the MAF@5v.

 

In the article they even said that they maxed out the MAF (running@5volts). Why didnt there's blow?

All rods and pistons have a breaking point. ALL OF THEM, I dont care what they are made out of. Why didnt theres break, when others have broken them with less power?

I personally dont see it lasting but a couple of runs down the track, because as Incon306 said a dyno does not put a real world load on the motor.

I HOPE IT DOES HOLD UP!! That will help everyone figure out what really is going on with our internals, AND it will keep me from rebuilding a bottom end to handle that kind of power.

I hope they update that article often.

Jason