not so bad

[Speed Racer]

View attachment 14607

View attachment 14608 I just got back from the dyno. Although the fuel mix is very rich the times were adequate. Guy seems to think i added the intake and exhaust the computer is trying to compensate by adding more fuel. Although this sounds plausible I'm not convinced. Any opinions?

Thanks,

Perry

 

[Stingray]

If anything the CAI and exhaust will slightly lean out the A/F at WOT. At WOT the PCM does not adjust A/F based on O2 readings, it just goes off of preprogrammed tables.

 

[VA VIPERAM]

Stingray is right. It goes to open loop and reads a table for A/F ratio at full throttle, so if you added anything like CAI or exhaust, it should lean out. From looking at your results, I would question his equipment. I've seen very few gasoline engines that have a horsepower peak below the torque peak with respect to RPM.

 

[Deibs]

My neck hurts,,

Wasn't it Mustang Dyno's that read low on these trucks or was that Dyno-Jet??

 

[Stingray]

My neck hurts,,

Wasn't it Mustang Dyno's that read low on these trucks or was that Dyno-Jet??

Mustang dynos normally read lower on any vehicle compared to a Dynojet. Some say that the Mustang dyno is closer to the actual hp the vehicle makes. I don't know my self :dontknow:

 

[Speed Racer]

okay

So I'm back with what the heck is causing it?!? As you can see the numbers are very rich. So I'm reading these as normal for us. Also, I was running with 93 octane and octane booster in these runs. Couldnt that also raise the richness? Still getting the weird power losses. We saw it on the dyno too. Dave, youre saying just go ahead with the Roe and the vec programming takes care of it? Sorry 'bout the pics but it was the best I could do this time. The guy explained the Mustang is suppposed to be more accurate on these trucks and read a little low.

 

[Black1]

It really does SUCK, how much power the auto tranny uses in our QC's.

 

[Speed Racer]

+1

It really does SUCK, how much power the auto tranny uses in our QC's.

Yah, it IS a bit less than I expected, but from what I'm reading these numbers are parr. What could cause the power loss though? :dontknow:

 

[Prof]

How is your transmission? If bands slip it is like a clutch slipping and can cause a fall off of power, you can often see it on a dyno curve as the bands slip..

You will need to do some transmission work to hold the Roe, I would do that at the same time you put in the Roe...one of the two should solve your power loss, for sure.

 

[Speed Racer]

power falloff

How is your transmission? If bands slip it is like a clutch slipping and can cause a fall off of power, you can often see it on a dyno curve as the bands slip..

You will need to do some transmission work to hold the Roe, I would do that at the same time you put in the Roe...one of the two should solve your power loss, for sure.

Welp, I noticed this after the muffler change. The truck had 300mi on it at the time. Had not noticed anything amiss before then. Now this happens reguarly other than the falloff nothing has happened other than that. i was wondering. If I take the battery cables off will the computer reboot (kinda like a coldstart) and reset itself?

Perry

 

[nycstev]

Mine Dynoed at 360. Smelled burning clutch duting the dyno. I Had 2000 miles at the time

 

[Prof]

Perry, you are correct, it is just like a cold boot. Just disconnect the negative terminal...(10 mm), leave it disconnected for 10 or 15 minutes...should clear any false codes, and reset the cpm.

Roy

 

[Texas Yellow Fever]

It really does SUCK, how much power the auto tranny uses in our QC's.

I don't know about all that...I think there's something else wrong here...his numbers are way low, compared to mine. This was on a 100 degree day with a heat soaked engine.

 

[FSTJACK]

The AF is going to be rich on a stock tune, even with a few mods.

The power seems down and the dyno sheet indicatess it was shut off at a very low RPM.

The QC's need to be in tow haul mode for a dyno pull.

The dyno operator can make a huge difference in real #'s or something that is just irrational.

Were these #'s SAE corrected, STD or raw?

 

[FSTJACK]

I don't know about all that...I think there's something else wrong here...his numbers are way low, compared to mine. This was on a 100 degree day with a heat soaked engine.

You make big #'s, BIG BOY.............

 

[Texas Yellow Fever]

You make big #'s, BIG BOY.............

Hehehehe...once upon a time maybe...but not any more...LOL!!!

 

[Speed Racer]

raw #'s as far as I know

The AF is going to be rich on a stock tune, even with a few mods.

The power seems down and the dyno sheet indicatess it was shut off at a very low RPM.

The QC's need to be in tow haul mode for a dyno pull.

The dyno operator can make a huge difference in real #'s or something that is just irrational.

Were these #'s SAE corrected, STD or raw?

raw #'s as far as I know