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Old 10-27-2009, 04:55 AM   #1
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I have no air leaks. The car wouldn't idle correct if I did. It could be a few things. Small diameter cats designed for a 2.5. Gotta clean my air filter and change my plugs. I'll start there. Dynos are not good for measuring but good for before and after which is what we are doing here.
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Old 10-27-2009, 05:46 AM   #2
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Quote:
Originally Posted by JAAY
I have no air leaks. The car wouldn't idle correct if I did. It could be a few things. Small diameter cats designed for a 2.5. Gotta clean my air filter and change my plugs. I'll start there. Dynos are not good for measuring but good for before and after which is what we are doing here.
My old 99' had a minor air leak after I cleaned the throttle body and it idled fine and took 500+ miles to set it off.
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Old 10-27-2009, 06:21 AM   #3
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Probably another 30 hp left on the table from these curves. Get your exhaust breathing right for a 3.4L, remap A/F ratios and she will start singing.
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Old 10-27-2009, 07:03 AM   #4
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That is what I am thinking.. I am doing a basic tune up today. Clean the filter change the plugs. It is all in the mapping though. I am down in the mid 11's most of the chart and even down to 10.5 when it switches to high cam. I am going to talk to fvd later on maybe and see what there input is. I was looking at other 996 3.4 graphs and many of them make about 245 at the wheels. So I am not far from that and each dyno is different. I still have to go back for 2 more pulls just to see if the techno torque has actually synced up with the computer or not. Stay tuned. I do agree though that the reflash should be the next step.
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Old 10-27-2009, 09:35 AM   #5
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Jaay, I've seen very similar A/F curves for the Pontiac GTO. I just bought one and have been looking at a lot of dyno curves. With the GTO it's mapped to be very rich 10.5 to 11.0 throughout the rev band. Tuners then make a lot of money by just re-mapping the A/F ratio and giving the car 20 HP. Why does Pontiac do this though? Very simple - a rich mix is less prone to detonation, it's safer for the engine. My guess is that Porsche tunes their cars in a similar manner. An ECU reflash then would resolve this.

Kirk
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Old 10-27-2009, 09:52 AM   #6
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Yup.. trying to get in touch with rhonda over at fvd now..
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Ebay Headers, Fabspeed high flow cats, JIC Cross, IPD Plenum, H&R Coilovers, B&M Short Shifter, AEM Uego Gauge Type Analog, Apexi S-AFC Select, 987 air box, Litronics, 2000 Tails and side markers, painted center console, 18" 987 S-Wheels, GT3 Front bumper with splitter.
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Old 10-27-2009, 12:15 PM   #7
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Re-Dyno fund is up to $40

Thanks
60 more to go.
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996 3.4 engine with 2.7 986 5speed transmission
Ebay Headers, Fabspeed high flow cats, JIC Cross, IPD Plenum, H&R Coilovers, B&M Short Shifter, AEM Uego Gauge Type Analog, Apexi S-AFC Select, 987 air box, Litronics, 2000 Tails and side markers, painted center console, 18" 987 S-Wheels, GT3 Front bumper with splitter.
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Old 10-27-2009, 12:42 PM   #8
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Quote:
Originally Posted by JAAY
Yup.. trying to get in touch with rhonda over at fvd now..
Jay, you may want to get in touch with these folks. They offer ECU tuning for cheaper than many of the other companies. No affiliation. They have dealers that can do it for you locally too.

I think this is the program you need for your 3.4L: http://www.upsolute.com/index.php?option=com_upsolute&task=car&id=282&id_marke=18&id_model=75
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Old 10-27-2009, 06:33 PM   #9
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Quote:
Originally Posted by Kirk
Jaay, I've seen very similar A/F curves for the Pontiac GTO. I just bought one and have been looking at a lot of dyno curves. With the GTO it's mapped to be very rich 10.5 to 11.0 throughout the rev band. Tuners then make a lot of money by just re-mapping the A/F ratio and giving the car 20 HP. Why does Pontiac do this though? Very simple - a rich mix is less prone to detonation, it's safer for the engine. My guess is that Porsche tunes their cars in a similar manner. An ECU reflash then would resolve this.

Kirk

I had to laugh when I read your post Kirk. I'm on my second GTO (first one got totalled by a 16 year old who had his license all of 4 days, he pulled out in front of me 2 years back) and got dang near exactly 20 hp from A/F adjustments alone. Now I know why it popped so much on second gear deceleration. VERY stout cars, got over 100k w/o issues from my first one and just turned over that in my newer one.....



Please keep us posted Jaay, I'm curious of the results.
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