Thought I would share some numbers 2.8" pulley

[KenBMD]

Great forum, just found it! I thought I would share some numbers with you. This is a bone stock GT with 25 miles on it. Only modification is our 2.8" pulley and our tune. Car is now at Stainless Works Exhaust getting a full custom exhaust and then will be back for further tuning. MAF was pegging so we didn't pull it any higher, but we will address that on the retune.

 

[Fast Freddy]

new car with only 25 miles on it and already modded and dyno'd. so much for breaking in the engine :smash

i won't be buying this one :rolleyes

 

[KenBMD]

new car with only 25 miles on it and already modded and dyno'd. so much for breaking in the engine :smash

i won't be buying this one :rolleyes

There's no harm in dynoing a new car like this. It's the people that take it too easy during break in that will have the issues.

Ken

 

[Mod Friendly]

So the fact that if you get a new vehicle regardless of its class the suggested break in period doesnt mean anything. Good #s but not as accurate as if you were to put lets say 500 miles on it then do a service then let her rip again. Simple knowledge, but hey to each is his own I guess.
My bikes Ive had em all serviced at 500 miles for the initial break in period, after that its somewhat harder riding for another 500 miles then you can do what you wanna do to it.

 

[Neilda]

I think, as has been discussed here a few times, that showing a little restraint and respect to a new engine will ultimately pay dividends with an oil tight, no rattle, rapid and reliable engine (in my experience).

Driving the snot out of a new car might be fun, but if you intend keeping it, it's not the most wise course of action. I wouldn't drive it like my granny, but nor would I drive it like a madman for the for the first 750 miles or so.

 

[50 BMG]

...Car is now at Stainless Works Exhaust getting a full custom exhaust...

Oh RIGHT ON!!!

Get some pics of that SW setup on the car and let us know what the price is for their exhust setup.

 

[KenBMD]

Oh RIGHT ON!!!

Get some pics of that SW setup on the car and let us know what the price is for their exhust setup.

Sure will.


As for running the car with so low miles, I don't completely disagree with you guys. If it were my car, I wouldn't. And I did suggest a longer break in. But the customer didn't want to wait. But I will stand behind the fact that a few dyno pulls are not going to make that much of a difference.

Taking it out on the road and driving it hard for 15 minutes is much worse on it than 1 dyno pull under controlled conditions.

*edited for content*

 

[californiacuda]

Some experts say, break them in like you are going to drive it. With the thinking being to aid the rings scraping and seating against the cyllinder walls.

 

[analogdesigner]

Would prefer a BEFORE and AFTER graph!

Great forum, just found it! I thought I would share some numbers with you. This is a bone stock GT with 25 miles on it. Only modification is our 2.8" pulley and our tune. Car is now at Stainless Works Exhaust getting a full custom exhaust and then will be back for further tuning. MAF was pegging so we didn't pull it any higher, but we will address that on the retune.

Ken,

Nice dyno curves! However, you forgot to attach a "before" plot! A baseline value is important, since the same car can give different readings on various dyno's.

The other guy's would know this, but doesn't this car need at least 50 miles on the odometer for the car's engine control computer to set itself properly?

Thanks,

Jay

 

[analogdesigner]

Break in theories

Some experts say, break them in like you are going to drive it. With the thinking being to aid the rings scraping and seating against the cyllinder walls.

I remember hearing this theory on a new rebuilt motor (with seasoned block). Fire up the engine (again, this assumes a rebuilt one) as quickly as possible, varying the RPM's. Give it several hard pulls (don't get crazy on the RPM's) to promote ring seating as you mentioned above.

 

[KenBMD]

Ken,

Nice dyno curves! However, you forgot to attach a "before" plot! A baseline value is important, since the same car can give different readings on various dyno's.

The other guy's would know this, but doesn't this car need at least 50 miles on the odometer for the car's engine control computer to set itself properly?

Thanks,

Jay

Unfortunately we don't always get that opportunity. Especially on projects like this. Different cars do dyno differently on different days/dynos, but I can assure you that every GT would dyno within 10-15 rwhp on a dynojet in stock form.

In this case, we are in Cincinnati and the customer is from MO. He sent us the blower to make a pulley for it, then we shipped the blower back to him with the new pulley and he reinstalled it. So I didn't get my hands on the car until after the pulley was installed.

This graph I posted is really the baseline for the project. Our main goal here is to get good before/after numbers on the exhaust.


Ken

 

[analogdesigner]

Understand...

Unfortunately we don't always get that opportunity. Especially on projects like this. Different cars do dyno differently on different days/dynos, but I can assure you that every GT would dyno within 10-15 rwhp on a dynojet in stock form.

In this case, we are in Cincinnati and the customer is from MO. He sent us the blower to make a pulley for it, then we shipped the blower back to him with the new pulley and he reinstalled it. So I didn't get my hands on the car until after the pulley was installed.

This graph I posted is really the baseline for the project. Our main goal here is to get good before/after numbers on the exhaust.


Ken

Ken,

I completely agree with your statements. It still would had been nice to see a "pull" with a stock engine setup (with >50 miles on it).

Good luck in meeting your performance goals, Jay

 

[nota4re]

THE most important spec when increasing the psi on a blown motor is air/fuel ratio. Are you capturing A/F on the dyno pulls and, if so, can you post the corresponding graph through the RPM range?

The other guy's would know this, but doesn't this car need at least 50 miles on the odometer for the car's engine control computer to set itself properly?

The ECU is going to be constantly setting long and short term fuel trims as it breaks-in. These values are useful to the ECU as it helps it to attain stoichiometric (14.7:1) air fuel ratio while in closed-loop mode. In heavier throttle conditions, the ECU will exit closed-loop mode in favor of open-loop where instead of monitoring the O2 sensors, it controls injector pulse duration and timing based on pre-programmed tables.

Herein lies the potential problem cited above. When boost is increased, the ECU doesn't necessarily have the right look-up table values to meter enough fuel. At some point, the A/F can go lean and then it is bye, bye motor. Remember, in open-loop mode (all dyno runs, for example), the ECU is not monitoring O2's for A/F.... so it has no idea of a lean condition.

This is why virtually every tuner will provide some kind of engine management modification (some better than others) and not "simply" a mechanical means to achieve more boost.

So, I guess my question to KenBMD is if they plan to supply some kind of supplemental engine management or, alternatively, have they validated through testing that the A/F's are OK with modest psi increase.

 

[analogdesigner]

Well stated!

THE most important spec when increasing the psi on a blown motor is air/fuel ratio. Are you capturing A/F on the dyno pulls and, if so, can you post the corresponding graph through the RPM range?



The ECU is going to be constantly setting long and short term fuel trims as it breaks-in. These values are useful to the ECU as it helps it to attain stoichiometric (14.7:1) air fuel ratio while in closed-loop mode. In heavier throttle conditions, the ECU will exit closed-loop mode in favor of open-loop where instead of monitoring the O2 sensors, it controls injector pulse duration and timing based on pre-programmed tables.

Herein lies the potential problem cited above. When boost is increased, the ECU doesn't necessarily have the right look-up table values to meter enough fuel. At some point, the A/F can go lean and then it is bye, bye motor. Remember, in open-loop mode (all dyno runs, for example), the ECU is not monitoring O2's for A/F.... so it has no idea of a lean condition.

This is why virtually every tuner will provide some kind of engine management modification (some better than others) and not "simply" a mechanical means to achieve more boost.

So, I guess my question to KenBMD is if they plan to supply some kind of supplemental engine management or, alternatively, have they validated through testing that the A/F's are OK with modest psi increase.

YES! This is very well stated! Jay

 

[BlackICE]

There are some O2 sensors that can work at wide open throttle. I wonder why no cars come from the factory with these type os sensors? Is it a cost issue?

BlackICE

 

[nota4re]

There are some O2 sensors that can work at wide open throttle. I wonder why no cars come from the factory with these type os sensors? Is it a cost issue?

More accurately, there are O2's capable to be than more than essentially binary devices around stoichiometric when combined with a wideband device. They can provide realtime A/F numbers through a given range. And yes, the issue is both cost and reliability of the O2's. Honda introduced some "high efficiency" varients of a car model (CRX?) in the late 90's that used these o2 sensors, but no manufacturer (to the best of my knowledge) is using these today. Instead, all are using look-up tables for open-loop mode that is simultaneously accurate, less costly, and more reliable. It just presents more challenges (and expense) for us go-fast junkies!

 

[KenBMD]

THE most important spec when increasing the psi on a blown motor is air/fuel ratio. Are you capturing A/F on the dyno pulls and, if so, can you post the corresponding graph through the RPM range?

Absolutely. I wouldn't even think of doing a dyno pull without a wideband. In fact, I wouldn't think of doing a dyno pull without a top quailty wideband. I use the afm-1000 here, most dyno shops use widebands with the much cheaper Bosch sensor that is very inaccurate depending on the age of the sensor.

The ECU is going to be constantly setting long and short term fuel trims as it breaks-in. These values are useful to the ECU as it helps it to attain stoichiometric (14.7:1) air fuel ratio while in closed-loop mode. In heavier throttle conditions, the ECU will exit closed-loop mode in favor of open-loop where instead of monitoring the O2 sensors, it controls injector pulse duration and timing based on pre-programmed tables.

This is actually not 100% correct. Your statements about closed loop are correct, but not for open loop. What you are describing is a speed density type system that uses VE tables for fuel delivery during open loop. The Ford GT and all newer Fords are mass air cars. There is a mass air transfer function that if calibrated correctly (not always true from the factory) you can indeed increase boost and still get the commanded A/F ratio. Since the MAF is measuring the mass of the air entering the engine (if the transfer function is indeed correct) it can add the proper amount of fuel. That does not make running a pullied car ok without a tune, but the WOT A/F is not the main issue when tuning a car that is pullied for more boost. There are many other things that do need to get changed.

Herein lies the potential problem cited above. When boost is increased, the ECU doesn't necessarily have the right look-up table values to meter enough fuel. At some point, the A/F can go lean and then it is bye, bye motor. Remember, in open-loop mode (all dyno runs, for example), the ECU is not monitoring O2's for A/F.... so it has no idea of a lean condition.

Read above about the lookup tables. But you are right, the car has no way of knowing it is lean during WOT.

This is why virtually every tuner will provide some kind of engine management modification (some better than others) and not "simply" a mechanical means to achieve more boost.

So, I guess my question to KenBMD is if they plan to supply some kind of supplemental engine management or, alternatively, have they validated through testing that the A/F's are OK with modest psi increase.

We do all of our tuning with the SCT Advantage software. We were one of the very first dealers in the country for SCT and have been one of their leading dealers since the beginning. We are very well known for our work with the 03/04 Cobras and much of that experience directly carries over to the GT.

Hopefully that gives you a better idea of how we handle a car like this. Feel free to ask any other questions you may have. Of course I'm over simplifying above, but I'm just looking to give you the general idea. If anyone has any specific questions about the EEC V strategies, just let me know. I'll post the dyno graph above with A/F included in a few minutes. Tuning a Ford Lightning right now. :thumbsup

 

[analogdesigner]

More O2 sensor, A/F ratio info

Yes, my Honda Insight (Hybrid) uses (two, I think) wideband 02 sensors. They area capable of measuring from about 10:1 up to about 24:1 (hyperlean!). The Honda Insight engine can operate at 22:1 under lightly loaded conditions (freeway speeds, <65 MPH, level roads). I routinely get 70 to 95 MPH during my one hour commute to San Diego. This requires skill in driving to achieve this level.

I think that Horiba owned the patent rights to the original wideband sensor (due to high development cost) and it was very expensive back in those earlier days, about $500 each! Jay

 

[KenBMD]

LOL, things haven't changed that much. The sensor I use costs $400


Here is that graph with A/F

 

[AMB]

Ken

Did you change the "STOCK GT" AFR from 12:1 to 11.5:1??

AMB