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Dynoed and modified my GT500...read on folks.


FordGeek

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It takes 50 drive cycles for the pcm to learn itself and run correctly. If you ever reset your pcm by pulling the battery you will notice the chopiness. The aftermarket shifter will be "needed" for those of us used to an aftermarket shifter. I know it felt sloppy to me but then again I have an mgw orange handle I drive with every day. And trust me ford does engineer serious retardation in with the knock sensors. My mach's knock sensors pulled 12-16 degrees during testing done by SCT when they had my car for the SCT 2 development. Heat makes a huge difference.

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BlueOval,

 

You are right in that only the adaptive fuel trims would change.

But (and you may find this hard to believe), I've been drag racing both Lightnings and Cobra's for the last seven years and I have seen many instances where resetting the PCM has dropped quarter mile ET's in excess of 0.3 seconds on street driven SVT vehicles on back to back runs with no reset versus resetting the PCM. The extra horsepower to accomplish such a gain has got to come from somewhere. I believe that the fuel trim values learned when driving in normal traffic do not allow maximum power under hard acceleration. It takes a while for the PCM' adaptive learning to figure out a new stategy for drastically different driving conditions (as on a dyno) and this time can be shortened considerably by starting over with the default values. There are many guys in my Lightning club which could attest to this phenomenon.

I was only trying to point out an area which has yet to be questioned in FordGeeks results, and I would still like an answer from him if the GT500's PCM was reset in the course of his dyno session.

 

LB

 

 

LB, I've reset the PCM at the track many times and have not noticed a diff but that sure doesn't mean it won't make a diff. Every case is probably unique. ha, if I could gain .3s by resetting, I'd do it all the time!!! lol Now you have me curious so I'd like to know if he reset it, too! Maybe they disconnected the battery during the exhaust/gear upgrade?

 

If I recall, I don't think the fuel trims even matter at WOT anyway. It's ignoring the 02's at that point.

 

What I'd REALLY like to see is another set of dyno #'s from a different GT500 on a different dyno. That could really get teh conversation going!

 

 

 

 

 

 

 

It takes 50 drive cycles for the pcm to learn itself and run correctly. If you ever reset your pcm by pulling the battery you will notice the chopiness. The aftermarket shifter will be "needed" for those of us used to an aftermarket shifter. I know it felt sloppy to me but then again I have an mgw orange handle I drive with every day. And trust me ford does engineer serious retardation in with the knock sensors. My mach's knock sensors pulled 12-16 degrees during testing done by SCT when they had my car for the SCT 2 development. Heat makes a huge difference.

 

 

hehe, yeah, first thing I did on my truck with the SCT PRP was turn the knock sensor off after 500RPM :)

 

The ProCharger was sending false signals all the time to the damn thing. I hear the new knock sensors are more accurate though.

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Lots of good idea's and a couple thoughts. I wonder Joseph if you have any way of getting the pulls graphs scanned in? I believe that the biggest differance was the temp of the motor air that day as Ford is very conservative in terms of pulling spark for obvious reasons. As such my suggestion would be to think about a thermostate along the lines of what was done with Terms. What about some kind of fuel line cool can? The top of the fuel tank and the start of the line is fairly easily accessable from under the rear seat so Maybe just as simple as a bag of ice? I also wonder what effect a bottle of good octane boost would show in relation to spark timing curves. And as a final thought on the very quick and easy side of it what about a couple bottles of water wetter? These are cheap and simple ways to try and see some gains while you are waiting on some of the hard parts. Thanks again, and hope you are enjoying this as much as us!! :party: edit: I wonder if you have thought to pull the crankcase vent and get a handle on how much might be leaking past the rings at this early stage? A boosted car will tend to pull an awful lot back out the top of the engine even though the eaton has a partial pressure release valve on it. Some possibility for tweaking here? I believe all these Romeo Niche line engines are hot run to check for leaks for at least five minutes on a factory break in so I can't see it being an issue, however.

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Very good info fordgeek...... not to change subjects from dyno, but my Shelby comes in mid-august and the first thing I am planning on doing is changing the exhaust. I have decided on the Bissani axle-back system. The Bissani Rep. tells me they are trying to line-up a Shelby to to get the templates fit. I wonder if anyone knows if say the '05 GT fit would work? Any replys would be appreciated. :sos:

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Very good info fordgeek...... not to change subjects from dyno, but my Shelby comes in mid-august and the first thing I am planning on doing is changing the exhaust. I have decided on the Bissani axle-back system. The Bissani Rep. tells me they are trying to line-up a Shelby to to get the templates fit. I wonder if anyone knows if say the '05 GT fit would work? Any replys would be appreciated. :sos:

 

 

Do a base dyno first! We all wanna know what's up with these things.

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Very good info fordgeek...... not to change subjects from dyno, but my Shelby comes in mid-august and the first thing I am planning on doing is changing the exhaust. I have decided on the Bissani axle-back system. The Bissani Rep. tells me they are trying to line-up a Shelby to to get the templates fit. I wonder if anyone knows if say the '05 GT fit would work? Any replys would be appreciated. :sos:

 

 

Dunno. But I was thinking you're doing the Bassani's for better sound, I assume? Because I think you'll see little/no diff in output from any axle-back on this car IMHO.

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Dunno. But I was thinking you're doing the Bassani's for better sound, I assume? Because I think you'll see little/no diff in output from any axle-back on this car IMHO.

 

Primarily for the sound, however in reading the diagnostics from a comparison of several brands on the '05 GT, it is not unrealistic to see alittle improvement in HP and Torque. How much? I guess I will have to dyno it to see. I will keep you informed once that happens.

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Because I think you'll see little/no diff in output from any axle-back on this car IMHO.

 

 

Im with you in a way. Im sure you will gain some HP from a muffler swap this is given. Sure it has 2.5" pipe unlike the 03/04 which came with 2.25" pipes and you would see a nice gain from a cat-back. But when a muffler is this quiet (ala 03/04's) your gonna see something.

 

 

 

People are comparing mufflers (powerwise) that were tested on a GT which is N/A for the GT500, Totally different beast.

 

 

Everytime I hear a car with Bassani, Corsa I think of some rice burner. Then again, To get the sound they make you can head down to your local parts store and toss in some Cherry bombs. Basicly the same thing for $20 a piece. :hysterical:

 

They sound like a lion that got kicked in the nutts. No low rumble. But to each their own.

 

 

Here is a good article to read. Watch the stock sound clip first. And I do know this is a GT and not a Shelby.

 

http://www.fordmuscle.com/archives/2005/03...flers/index.php

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Its all about cfm's. Flowmaster is the worst flowing on the market but have a great sound and thats why I have them. They will make 1-2 hp difference max I suspect. At most up to 5 due to the shelby being blown. Again its my opinion and not based on fact as unfortunately I don't have my shelby yet. PSDS to the max. Window paignes on tall buildings are looking awful inviting.

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It seems to me that 4.10's on this car with street tires (even the wide Eagle F1's) are going to make a heck of alot of smoke when you launch er hard. With some slicks I think you will be the man. I was shocked Ford went with 3.30's and it does sound like this bogs the car from start a bit from the FEW owners reviews I've read. Sounds like a gear swap (maybe 3.70's) and a tune might be all this car needs to get in the low 12's where it should be.

I hope SCT and the Diablosport boys already have a car to break the silver oak code.

Fordgeek more driving impressions please!!

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Im with you in a way. Im sure you will gain some HP from a muffler swap this is given. Sure it has 2.5" pipe unlike the 03/04 which came with 2.25" pipes and you would see a nice gain from a cat-back. But when a muffler is this quiet (ala 03/04's) your gonna see something.

People are comparing mufflers (powerwise) that were tested on a GT which is N/A for the GT500, Totally different beast.

Everytime I hear a car with Bassani, Corsa I think of some rice burner. Then again, To get the sound they make you can head down to your local parts store and toss in some Cherry bombs. Basicly the same thing for $20 a piece. :hysterical:

 

They sound like a lion that got kicked in the nutts. No low rumble. But to each their own.

Here is a good article to read. Watch the stock sound clip first. And I do know this is a GT and not a Shelby.

 

http://www.fordmuscle.com/archives/2005/03...flers/index.php

 

 

Thanks for the link, wildo... I've always loved the deep throaty sound of Flowmasters (and Magnaflows are starting to sound very similar). My comments on raw_power's post was because the headers on the Shelby look to be a zero-tube-length plenum design (if you check out Bold Moves Episode-4, the V6 and 4.6L headers look nice but not the Shelby's are flat to the exhaust ports) which would stiffle an NA motor but probably work ok with forced induction (in an emissions-legal street context). So, I was thinking that improvements downstream from them would not yield much benefit, but I guess it can't hurt either! Can't help but wonder what's in this motor with a CAI, some more boost and induction-tuned tri-Y headers. According to the Shelby rep at NYIAS, it's an easy trip to near 650HP and he strongly implied that Ford dyno'd this motor with similar mods as part of testing. Is this gonna be fun or what?!

 

I've also heard that the Ford GT with similar mods (CAI/headers/+boost) plus aftermarket reworked heads (with non-emissions-legal cams) gets into the vicinity of 800crankHP but I doubt I'd swop the heads. At least in places like NYC there'd be no chance passing emissions, but up here in the country with no testing it's very tempting ...hmmmm :)

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It seems to me that 4.10's on this car with street tires (even the wide Eagle F1's) are going to make a heck of alot of smoke when you launch er hard. With some slicks I think you will be the man. I was shocked Ford went with 3.30's and it does sound like this bogs the car from start a bit from the FEW owners reviews I've read. Sounds like a gear swap (maybe 3.70's) and a tune might be all this car needs to get in the low 12's where it should be.

I hope SCT and the Diablosport boys already have a car to break the silver oak code.

Fordgeek more driving impressions please!!

 

 

Yeah, the 3.31s are kinda tall but I suspect they did that to minimize gas guzzler tax. At least with the big 2.97 first gear (vs 2.48 in the T56) that 3.31 is more like a 3.90+. With 4.10s and slicks, the 1-2 shift will come up really quick! (kinda shades of NHRA pro-stock) :)

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Yeah, the 3.31s are kinda tall but I suspect they did that to minimize gas guzzler tax. At least with the big 2.97 first gear (vs 2.48 in the T56) that 3.31 is more like a 3.90+. With 4.10s and slicks, the 1-2 shift will come up really quick! (kinda shades of NHRA pro-stock) :)

 

Can't recall if FordGeek already answered this, so I apologize if it's duplicated. Did switching to the 4:10s help the clutch "chatter" on launch? I would think it would help.

 

Dave

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Can't recall if FordGeek already answered this, so I apologize if it's duplicated. Did switching to the 4:10s help the clutch "chatter" on launch? I would think it would help.

 

Dave

 

 

I don't recall seeing that mentioned, Dave, but it's possible I missed it too. He did mention that 1st gear with the 4.10 is brief :)

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apparently the gears did the trick

 

"For those of you that have your Shelby's, the gear change fixed the "problem" we've been experiencing with the little jiggy the car does coming out of first. I think it was simply a bog given the lower than needed gearing."

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apparently the gears did the trick

 

"For those of you that have your Shelby's, the gear change fixed the "problem" we've been experiencing with the little jiggy the car does coming out of first. I think it was simply a bog given the lower than needed gearing."

 

 

I'm assuming all of this is with TC off? I hope.

.

 

 

4:10's with any engine is brief - hence the 4:10's? :hysterical:

 

 

:doh: what was I thinking? :)

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hmm... FordGeek strangely absent from his own thread... must be out driving and enjoying his new toy. lol

 

can't wait to see what some of the mods for this car do... at this point, I'm thinking wheels/tires, 3.70 gears, and *maybe* a pulley swap will be the extent of the mechanics for me. Its a fine line between a lot of fun power and power you can actually use and enjoy on a day-to-day basis.

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