I think the dyno was wrong.

[inline6power]

mach 6s have made over 600 on fuel. no reason why you shouldnt be over 600 with nitrous with your setup. sounds like you may need a little more nitrous. what jet are you using, how is it activated, when is it activated, and where is it plumbed in to?

 

[2141pete]

mach 6s have made over 600 on fuel. no reason why you shouldnt be over 600 with nitrous with your setup. sounds like you may need a little more nitrous. what jet are you using, how is it activated, when is it activated, and where is it plumbed in to?

It is just a little compucar nitrous in a bag kit. It plugs into the cigarette lighter, goes right in the back of the intake horn, and fires off a switch you puch. The line is so small I dont even run a jet in it. The bottle pressure was about 1100psi. I made one fuel only run at 475hp because the dyno broke but the others I made at the same time were all pretty much around a 70hp increase or so at 530-540hp. The 569/1080 run was first thing in the morning but they pulled me off the dyno after the first pull because My tires and rims were too wide and one was hanging half way off.

 

[Big Swole]

Dang I got a good one going here. Here is the breakdown for those that didn read the whole thing.
mods= studs, o-rings, ats 3 piece, mach 5's, grid heater delete, AD150, Quad ADR, built tranny, TC lockup switch, smarty on stock software, SO vp44, about a 70hp shot of nitrous.

1/4 mile= 12.85@104 at about 7200 pounds on #2 only
Dyno numbers= 475/97x on fuel only, 569/1080 on spray.

I just didnt think it added up.

Like I said ealier in this thread....Your in the 12's!!! That's great!!

Just keep going to the track and use the HP Calculator to figure it out....

Don't worry bout the dyno!!

 

[2141pete]

Like I said ealier in this thread....Your in the 12's!!! That's great!!

Just keep going to the track and use the HP Calculator to figure it out....

Don't worry bout the dyno!!

It's got me so pissed off that I'm going to run it wed and friday and probly next wed just to see how fast I can get down to. I'm just mad that I drove so far to feel like an ass for not making the power I wanted. But it happens to everyone.

 

[2141pete]

I will re-emphasize several points regarding Dynojets that have been mentioned many times in the past.

1- There really is no "calibrating" that is needed on a Dynojet. If all the sensors are clean, it works. If not, it doesn't work. And when I say "doesn't work" does not mean it reads low, it means it doesn't work!!

2- A Dynojet is an accelerometer. It measures the HP, or work, it takes to accelerate a known weight (the drum), over a given time. You can't "fool" it.

3- If your uncorrected HP obtained on a Dynojet is not within 5% of your trap speed calculated HP, it merely shows your setup is not tuned properly!! It does NOT mean it's reading low!!

4- Doing 3 pulls on a dyno a couple times a year will only produce a number!! It takes hours and many pulls on the dyno to "tune" the truck and get "real" "track driven" HP numbers!oke:

What if it was loaded improperly do you think that could throw #'s out of wack?

 

[Dockboy]

What if it was loaded improperly do you think that could throw #'s out of wack?

A Dynojet 248C is not a load dyno.

My educated guess (not being there or seeing the graph) is you are probably fueling too much down low in the rpm range.

 

[2141pete]

I appreciate all the comments fellas. I'm gonna try and get back on as soon as I can but I'm pretty busy this timeof year with toys for tots and hurricanes. I think with some tuning I can definetly get alot more. I just wanted some input and opinions. I'm not an expert or diesel performance pro by any means just a guy with alot of money and wrench time in a truck that seems to have taken a big step back.

 

[2141pete]

A Dynojet 248C is not a load dyno.

My educated guess (not being there or seeing the graph) is you are probably fueling too much down low in the rpm range.

The only graph I got was from the very first run in the morning. I must have forgotten the other one.

 

[inline6power]

The only graph I got was from the very first run in the morning. I must have forgotten the other one.

i got my old 693hp dyno sheet. i will post it in a bit. i surely think you need more nitrous and for sure will be over 600. run a single 62 jet and set it to come on about 15psi . will rock and roll.

 

[2141pete]

A Dynojet 248C is not a load dyno.

My educated guess (not being there or seeing the graph) is you are probably fueling too much down low in the rpm range.

I thought they had to load the weight of the vehicle to apply resistance dynojets dont do this?

 

[2141pete]

i got my old 693hp dyno sheet. i will post it in a bit. i surely think you need more nitrous and for sure will be over 600. run a single 62 jet and set it to come on about 15psi . will rock and roll.

I'm gonna try more spray and a different dyno. It just sucks it's a few hours drive to the closest one.

 

[inline6power]

I thought they had to load the weight of the vehicle to apply resistance dynojets dont do this?

no dynojets measure how fast you can turn a mass in given amount of time, how fast you can turn the drum. a load dyno will load the truck and measure how well it holds or does against the load. inertia or dynojet is the best most accurate for our trucks hands down. hit your truck with just a little more juice and i think you will be happy with the results

 

[Lucky Jeff]

dynojets have definitely always given me higher numbers.. I figure it's good for bragging rights, but I call it cheating just cause it makes more. :woohoo: (Even if it is more accurate)

 

[Dockboy]

The only graph I got was from the very first run in the morning. I must have forgotten the other one.

The "concaved" ramp up in HP at lower rpms is a typical indication of too much fuel too soon. This condition inhibates combustion and causes turbo lag. On a Dynojet, by the time there is enough combustion to start to drive the turbo, the run is over. This poor tuning can be masked on the strip because you are not considering how long it takes to spool while staging and are leaving when the engine has gotten through this combustion "squelching" stage.

Bottom line, spend time on a Dynojet tuning the fuel at lower rpms, and the truck will dyno better AND run better on the street/strip.

 

[2141pete]

The "concaved" ramp up in HP at lower rpms is a typical indication of too much fuel too soon. This condition inhibates combustion and causes turbo lag. On a Dynojet, by the time there is enough combustion to start to drive the turbo, the run is over. This poor tuning can be masked on the strip because you are not considering how long it takes to spool while staging and are leaving when the engine has gotten through this combustion "squelching" stage.

Bottom line, spend time on a Dynojet tuning the fuel at lower rpms, and the truck will dyno better AND run better on the street/strip.

Sounds good to me, I'll give it a shot. Is that why some guys try to ride the breaks and spool before the run starts?

 

[inline6359]

this statement is totally wrong and bs.

ha ha i wasnt being a dick dude.......

Negative ghostrider......

 

[Rattlin_Ram]

What would someone have to use to adjust your fueling down low on a 24v? I can turn my sublevel on my comp down, but if I turn it below 5x4 I think it is, I defuel at higher rpms. Is an ADR capable of doing this?

 

[Dockboy]

To illustrate what I'm talking about, take a look at one of my dyno sheets and the video. It shows the "concaved" ramp up due to low rpm over-fueling more clearly. Unfortunatelly, I didn't get the chance to work on tweaking the tuning to help eliminate it :doh:

Click here to see Video

 

[2141pete]

I definetly see ehat you mean about it being concave. I'll look at some of my other sheets after work and see if they are the same way but I dont think they were.

 

[Dockboy]

Is that why some guys try to ride the breaks and spool before the run starts?

Yes it is.

Although, most people think they need to do this because a Dynojet doesn't "load" the truck:doh: In reality, it needs to be done because they don't have the truck tuned right!:kick: