Dyno Results (Final)

[IndyBlk5.0]

whats to hate about 260 ftlbs at 2k?

 

[IndyBlk5.0]

It was a DynoJet & it was @ the tail pipe.

I seen somewhere I think a Pro-M affiliate site that was offering em for like $149.00 "$20 cheaper than Pro-M's site" I got mine new on ebay for $100

Was it an individual selling it? I can't find any on ebay. Would you care too help a stanger out if you see something I don't? Thanks

 

[Ray@VSK]

This place states they have three new available for $120.00 each http://www.panhandleperformance.com/specials.html & http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33553&item=7930054265&rd=1 currnt bid is $36.00

 

[autoXr1]

Ray,
The reason I asked about whether it was a Dynojet or a Mustang is your air/fuel ratio readings may be different at the same RPM. A Dynojet will not load the engine like a Mustang. A Mustang produces measured results. A Dynojet calculated. A Mustang will create a more accurate and reproducable "real world" load that can mimic things like wind and rolling resistance...load will influence your fuel and timing curves...and air/fuel ratio. See where I am going with this? If you plan on adjusting your air/fuel ratio based upon this graph, you may be tuning based upon faulty data. So, you go ahead and tune based upon a Dynojet curve while the engine is under very little load, then get the car out on the road or on the track, in the real world and under real load, and your tuning is all off.

All that said, an intelligent, knowledgable, tuner knows this and will allow for some adjustment. So, sometimes a little over/undershooting on your fuel/timing tables in the right places under certain driving strategies on the Dynojet will land your tune just right when you are truly under load conditions.

The thing is, a shop can purchase 3 Dynojets for the price of one Mustang, so often money talks, and they hope they get some less-than-knowledgable customers that don't know the difference.

Your tune is only as good as the data you are basing it upon.

 

[Ray@VSK]

Ray,
The reason I asked about whether it was a Dynojet or a Mustang is your air/fuel ratio readings may be different at the same RPM. A Dynojet will not load the engine like a Mustang. A Mustang produces measured results. A Dynojet calculated. A Mustang will create a more accurate and reproducable "real world" load that can mimic things like wind and rolling resistance...load will influence your fuel and timing curves...and air/fuel ratio. See where I am going with this? If you plan on adjusting your air/fuel ratio based upon this graph, you may be tuning based upon faulty data. So, you go ahead and tune based upon a Dynojet curve while the engine is under very little load, then get the car out on the road or on the track, in the real world and under real load, and your tuning is all off.

All that said, an intelligent, knowledgable, tuner knows this and will allow for some adjustment. So, sometimes a little over/undershooting on your fuel/timing tables in the right places under certain driving strategies on the Dynojet will land your tune just right when you are truly under load conditions.

The thing is, a shop can purchase 3 Dynojets for the price of one Mustang, so often money talks, and they hope they get some less-than-knowledgable customers that don't know the difference.

Your tune is only as good as the data you are basing it upon.

I don't understand

 

[tmoss]

Ray,
The reason I asked about whether it was a Dynojet or a Mustang is your air/fuel ratio readings may be different at the same RPM. A Dynojet will not load the engine like a Mustang. A Mustang produces measured results. A Dynojet calculated. A Mustang will create a more accurate and reproducable "real world" load that can mimic things like wind and rolling resistance...load will influence your fuel and timing curves...and air/fuel ratio. See where I am going with this? If you plan on adjusting your air/fuel ratio based upon this graph, you may be tuning based upon faulty data. So, you go ahead and tune based upon a Dynojet curve while the engine is under very little load, then get the car out on the road or on the track, in the real world and under real load, and your tuning is all off.

All that said, an intelligent, knowledgable, tuner knows this and will allow for some adjustment. So, sometimes a little over/undershooting on your fuel/timing tables in the right places under certain driving strategies on the Dynojet will land your tune just right when you are truly under load conditions.

The thing is, a shop can purchase 3 Dynojets for the price of one Mustang, so often money talks, and they hope they get some less-than-knowledgable customers that don't know the difference.

Your tune is only as good as the data you are basing it upon.

So, your saying a dynojet does not load an engine much? I always thought dyno jets had a big inertia drum that loaded the engine through the chassis and I thought both measured torque and rpm from which HP is calculated. So, the dyno jets are junk and just bought to make a quick buck huh? But some guys know how to make it work right?

 

[autoXr1]

So, your saying a dynojet does not load an engine much? I always thought dyno jets had a big inertia drum that loaded the engine through the chassis and I thought both measured torque and rpm from which HP is calculated. So, the dyno jets are junk and just bought to make a quick buck huh? But some guys know how to make it work right?

http://www.ayaracing.com/faq.html Try this. It'll explain things a lot better than I could. The problem is inertia, or the type of load. Inertia-type dynos are not "junk" and I wouldn't say they are bought to make a quick buck in most cases, but I would say to be very careful with how to interpret the data received by inertia-type dynos because they do not reflect the type of load environment that your vehicle will see when it is driven on the road or track. Engine load influences the fuel/timing maps significantly, in turn, the air/fuel ratio. So, if the air/fuel ratio is reading lean on an inertial-type dyno at 2000-3000 RPM (cruise), it might not be, or perhaps lean to a lesser extent if done under steady-state load on a Mustang dyno.

 

[IndyBlk5.0]

this is interesting....

 

[Ray@VSK]

Well my car was lean @ low rpms lean & not dynojet mistaken, it was popping & overall just not running as strong as it was supposed to & I had it tuned on a dynojet & it ran great afterwards...

 

[autoXr1]

Well my car was lean @ low rpms lean & not dynojet mistaken, it was popping & overall just not running as strong as it was supposed to & I had it tuned on a dynojet & it ran great afterwards...

I believe you,... and many vehicles can be tuned fairly well using an inertial-type dyno. However, I am willing to bet that if you were to find a shop with an eddy-current (Mustang) dyno and did another series of pulls with air/fuel measurements pre-catalytic convertor (if applicable), then you may find areas to improve, especially in the area of part-throttle, cruise, and overall drivability. If you were able to compare your HP and torque curves, as well as, air/fuel curves they would be slightly different between the two types of dynos. Inertial-type dynos are at their most accurate during WOT pulls because the vehicle is trying to accellerate the rotation of those drums as quickly as it can...so there is a load as long as you are accellerating those drums. However, that is not representative of typical driving conditions...stop 'n go traffic, decelleration, up 'n down hills, steady cruise on the highway, pulling a heavy trailer with your truck, etc. Only an eddy-current dyno can mimic those conditions with manipulations in the dyno program. If you are trying to tune your vehicle for optimal drivability and power then you have to test and obtain data under similar conditions in which it will likely see once you leave the shop.

I guess what I am trying to say is that, one, there may be areas to improve with your tuning and power...you just need to find the right equipment and use the proper methods to do your testing, and two, be aware that there is a difference between dynos, so take that into consideration when reading your own data, or someone elses.

The reason I entered this thread was that, recently, I've been unlearning a lot of misinformation about engine tuning. I felt it important to share a little bit of what I have learned so others don't make the same mistakes I have.

Ray, good luck with the car and I'm glad you've got it running better.

 

[tmoss]

......then you may find areas to improve, especially in the area of part-throttle, cruise, and overall drivability.

'

this is exactly the areas of operation where the EEC adaptive control will create A/F ratios to suit it's own needs (14.7:1) and change any tuning that is done by writing correction factors to KAM and using them to modify A/F in the continuous closed loop operation.

 

[autoXr1]

'

this is exactly the areas of operation where the EEC adaptive control will create A/F ratios to suit it's own needs (14.7:1) and change any tuning that is done by writing correction factors to KAM and using them to modify A/F in the continuous closed loop operation.

Within limits. It just depends upon how "extreme" the mods are and how much control the particular tuning equipment software allows one to modify the EEC program, and where the desired/target AFR is at certain RPM and load points. A vehicle running a supercharger is going to have a different set of target values than one using nitrous or one that is naturally aspirated. As soon as you go into the computer and start changing fuel and timing curves, load tables are going to be altered, and this is where an eddy-current dyno is going to help you dial in the combo. You can actually put the car in cruise-control at any engine RPM, in any gear (manual), and independently change the engine load on the dyno, then tune out certain trouble spots. This is also great for those that have changed rear end gears (which shifts the load points) and/or have the newer electronically-controlled transmissions...you can alter the transmission shift points for improved accelleration or power during towing. Some folks have two-stage programs, one for streetability and mileage, another for race...again, different target values in the programs. Some folks have to turn off the adaptive control at the end of their final tune in order to prevent the EEC from altering/fighting the desired calibration. Some are able to have a more complex program that addresses the various driving strategies. It depends upon a number of variables and the desired tune.

With a mild naturally-aspirated combo, you're likely right that the EECs adaptive control will take over a fair amount of the job and get things pretty close.

 

[tmoss]

I agree - as long as the tuning device is mounted at the srevice connector (twEECer, EEC tuner, etc) and can intercept and change the EEC programming and turn off some functions - like adaptive control.

 

[IndyBlk5.0]

So are you saying that the computer will eventually just make the a/f ratio what it wants? Therefore eliminating the pro m optimizer in time?

 

[tmoss]

I was speaking about the EEC adaptive control and it's affect on fuel delivery by varying pulse width when A/F ratios are not what it wants - 14.7:1 for best mileage and emissions at part throttle.

Your Pro-M device calibrates the MAF air curve better from what I gather. This means your getting a more correct air/fuel ratio from the MAF sensor to start with at all load levels, not just part throttle where adpative control works.