Anyone with performance or computer mods?
May 9th, 2014, 9:36 AM
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Anyone with performance or computer mods?
Just curious if anyone ever did anything performance wise to their Uplanders?
So far I just have the AFE high flow drop in dryfilter (no oiling). I considered a custom intake setup but seeing how the K&N dyno on the Pontiac 3.9 only gained about 5hp at the very peak of the powerband (around 5-6k), I figured it wasn't worth it to me for the work and cost involved.
I've mic'd the catback exhaust at 2.5" OD which is a decent size though a slight increase in diameter could be advantageous in flow and some gain in power/torque though without dyno testing it's hard to say.
I'm pretty sure our exhaust is larger and freer flowing than the Pontiac G6 3.9 equivalent (tons of room under my cargo van though the resonator/muffler may be restrictive?). They gained about 10hp from a full 2.5" catback exhaust which may or may not be much if any larger than our own, so a 3" exhaust could possibly have some gains with or without proper tuning for it. I'm not sure as I'm new to GM performance and tuning.
However I did purchase a tuned engine and tranny computer setup from Overkill Motorsports out of canada. He provides an off the shelf tune and after searching the handful of 3.9 tuners (not many), he seemed to have the most experience with the 3.9 engine so I went with him.
I'm waiting to install these once we get the coolant leak resolved and I can't wait as the 3.9 VVT is a decent and flexible engine setup out of the box. I chose to stick with an 87 octane tune for now as it's a work van and I don't want to spend a ton on premium (it's much higher than 87 here).
Will did mention the downpipe is likely restricive on these engines so I'm going to look into getting a larger freer flowing downpipe later this year. I highly recommend Overkill's email support and customer service!
Jeremy
So far I just have the AFE high flow drop in dryfilter (no oiling). I considered a custom intake setup but seeing how the K&N dyno on the Pontiac 3.9 only gained about 5hp at the very peak of the powerband (around 5-6k), I figured it wasn't worth it to me for the work and cost involved.
I've mic'd the catback exhaust at 2.5" OD which is a decent size though a slight increase in diameter could be advantageous in flow and some gain in power/torque though without dyno testing it's hard to say.
I'm pretty sure our exhaust is larger and freer flowing than the Pontiac G6 3.9 equivalent (tons of room under my cargo van though the resonator/muffler may be restrictive?). They gained about 10hp from a full 2.5" catback exhaust which may or may not be much if any larger than our own, so a 3" exhaust could possibly have some gains with or without proper tuning for it. I'm not sure as I'm new to GM performance and tuning.
However I did purchase a tuned engine and tranny computer setup from Overkill Motorsports out of canada. He provides an off the shelf tune and after searching the handful of 3.9 tuners (not many), he seemed to have the most experience with the 3.9 engine so I went with him.
I'm waiting to install these once we get the coolant leak resolved and I can't wait as the 3.9 VVT is a decent and flexible engine setup out of the box. I chose to stick with an 87 octane tune for now as it's a work van and I don't want to spend a ton on premium (it's much higher than 87 here).
Will did mention the downpipe is likely restricive on these engines so I'm going to look into getting a larger freer flowing downpipe later this year. I highly recommend Overkill's email support and customer service!
Jeremy
June 11th, 2014, 12:45 PM
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Ah well I see I'm the black sheep here lol....However I'm always interested in improving the performance across the board (power, handling, etc) regardless of what I'm driving so I've done a few things so far to my '08 Uplander Cargo.
Performance wise, I've installed just a few things:
1. AFE dry drop in panel filter. It definitely looks more free flowing and makes a tad more noise but the factory piping, though ribbed like any OEM piping, looks more than free flowing enough to leave alone. Plus I believe after market intakes and filters have only freed up about 5hp near the top end so I'm not worried about it.
2. Retuned engine and transmission computers: I stuck to the 87 octane engine tune since I'm not looking to invest too much into the van right now but may have it retuned for 89 or 91 down the road.
I don't think it added a ton of power (maybe 5-10hp) but it's hard to tell as the tranny computer upgrade really transforms the behavior of this van.
I didn't really mind the stock tranny computer program but I mainly wanted tighter shifts to quicken shift response and protect the clutches from unnecessary wear.
Well, I think most will not like this tranny retune but I like it for the most part. The auto now almost behaves like a 'sport shift' or 'manumatic' automatic as it's very hesitant to upshift, especially in first or second gear.
That means when you take off in first that the transmission will try to hang there in first as long as you have any measure of throttle into it, almost like a stick shift, unless you almost completely let up on the accelerator to let it upshift. Just driving normally, the van will still prefer to shift up around 3-4k rpm or so and much prefers to be driven hard.
This can make the van more entertaining to drive but I suspect, at the expense of fuel economy to some degree. Just how much, I'll have to see.
I'm sure there's some measure of restriction in the exhaust between the giant resonator and small muffler (internal baffling,etc) but for now I prefer the quiet so maybe I'll tackle that down the road.
Next will be some minor work on tightening up the suspension with some better rear shocks, poly suspension bushings and dropping the rear to the standard long wheel base ride height.
Performance wise, I've installed just a few things:
1. AFE dry drop in panel filter. It definitely looks more free flowing and makes a tad more noise but the factory piping, though ribbed like any OEM piping, looks more than free flowing enough to leave alone. Plus I believe after market intakes and filters have only freed up about 5hp near the top end so I'm not worried about it.
2. Retuned engine and transmission computers: I stuck to the 87 octane engine tune since I'm not looking to invest too much into the van right now but may have it retuned for 89 or 91 down the road.
I don't think it added a ton of power (maybe 5-10hp) but it's hard to tell as the tranny computer upgrade really transforms the behavior of this van.
I didn't really mind the stock tranny computer program but I mainly wanted tighter shifts to quicken shift response and protect the clutches from unnecessary wear.
Well, I think most will not like this tranny retune but I like it for the most part. The auto now almost behaves like a 'sport shift' or 'manumatic' automatic as it's very hesitant to upshift, especially in first or second gear.
That means when you take off in first that the transmission will try to hang there in first as long as you have any measure of throttle into it, almost like a stick shift, unless you almost completely let up on the accelerator to let it upshift. Just driving normally, the van will still prefer to shift up around 3-4k rpm or so and much prefers to be driven hard.
This can make the van more entertaining to drive but I suspect, at the expense of fuel economy to some degree. Just how much, I'll have to see.
I'm sure there's some measure of restriction in the exhaust between the giant resonator and small muffler (internal baffling,etc) but for now I prefer the quiet so maybe I'll tackle that down the road.
Next will be some minor work on tightening up the suspension with some better rear shocks, poly suspension bushings and dropping the rear to the standard long wheel base ride height.
June 11th, 2014, 1:54 PM
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I changed out those mushy rear shocks on my '07 at about 20k miles .. I couldn't stand the swaying around corners and the effect the cross-wind had.
I installed a new pair of Monroe sensa-tracs on the back and that stiffened things up quite a bit. It handles like a different vehicle. Front struts are still original at ~75k
I also got under the van and cut that air-dam off with a wood crosscut saw. The van looks so much better and there has been no ill effect so far.
I installed a new pair of Monroe sensa-tracs on the back and that stiffened things up quite a bit. It handles like a different vehicle. Front struts are still original at ~75k
I also got under the van and cut that air-dam off with a wood crosscut saw. The van looks so much better and there has been no ill effect so far.
October 15th, 2014, 1:52 PM
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I have a magnaflow muffler on and cut the resinator off right above the rear "axle". Sounds awesome, but didn't notice much hp increase.
Was thinking of putting 20s on it, but my wife would prefer the gas mileage and I could save the money for one of my trucks haha
Was thinking of putting 20s on it, but my wife would prefer the gas mileage and I could save the money for one of my trucks haha
October 16th, 2014, 4:27 PM
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So you left the giant resonator in place and cut off the small muffler under the back bumper, then added the magnaflow?
At some point I'm getting rid of the giant resonator for something better flowing. i just don't want any drone with the van.
My car already has some from my mods including a header and larger exhaust.
At some point I'm getting rid of the giant resonator for something better flowing. i just don't want any drone with the van.
My car already has some from my mods including a header and larger exhaust.
October 17th, 2014, 9:59 AM
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I think you have it backwards? I little round thing by the bumper is the resonator and the giant thing in the middle is the muffler. So I replaced the larger can towards the middle (muffler) with a magnaflow muffler and cut off the smaller can (resonator).
What headers do you have? Did you notice much more hp?
What headers do you have? Did you notice much more hp?
October 18th, 2014, 1:16 PM
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Ha good catch, you are correct!
If you ever get the time or notion to record some audio, I'd love to hear it.
I've always modded my vehicles but this van is fairly quiet on the inside which I've grown to like especially with a modded audio system (another life long habit/hobby), so I'm not sure which muffler and what size and style I'll go with.
Exhaust sound tuning can be such an expensive affair and I don't want a loud, droning or raspy note. Flowmaster is out I think, though if you youtube it, there are a couple of decent sounding Impala 3.9s with Super 44 Flowmasters.
FWIW, the exhaust should be 2.5" but I believe it necks down after the muffler to 2.25 though I'm not sure why exactly (fitment, cheaper??).
BTW, I just changed the rear bank primary O2 sensor...that was fun.
If you ever get the time or notion to record some audio, I'd love to hear it.
I've always modded my vehicles but this van is fairly quiet on the inside which I've grown to like especially with a modded audio system (another life long habit/hobby), so I'm not sure which muffler and what size and style I'll go with.
Exhaust sound tuning can be such an expensive affair and I don't want a loud, droning or raspy note. Flowmaster is out I think, though if you youtube it, there are a couple of decent sounding Impala 3.9s with Super 44 Flowmasters.
FWIW, the exhaust should be 2.5" but I believe it necks down after the muffler to 2.25 though I'm not sure why exactly (fitment, cheaper??).
BTW, I just changed the rear bank primary O2 sensor...that was fun.
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October 20th, 2014, 10:41 AM
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Before I got the magnaflows I was told NOT to get the 44s due to drone. The MF isn't raspy at all. You can hear the exhaust from the inside. Maybe a little bit of nosie in the cab, but nothing too bad. I'll try to get an audio clip up. Its raining pretty good right now.
November 17th, 2019, 3:38 PM
#10
i have an 07 cargo, it has always felt extra bouncy which i didnt mind too much since i load it up... i have heard of a 'soft ride' uplander package, but i dont see any way of distinguishing replacement parts for a standard vs soft vs the cargo model... my one rear spring is sagging a bit more than the other so its time to do something.... i am putting 'ac delco professional' struts/shocks/springs on every corner... will this lower my cargo's height to a 'non cargo' height and stiffen the suspension to a 'non-cargo' suspension?
thanks
not sure when i will get around to doing the work, i already bought the parts, but any info helps