increase horsepower [Archive] - Jeep Commander Forums: Jeep Commander Forum

: increase horsepower


donutz
02-22-2006, 12:07 PM
has anyone done any mods to inc. their horsepower. ie: new exhuast system, air intake. I was told by getting after market equip. you can get better gas mileage and more horsepower. does anyone know anything about this?

pac
02-22-2006, 04:40 PM
Well , I'm sure if you get abetter breathing system youre gonna see gains. Less restrictions, more ability to respond better. In a while when they come out I will prob. get a nice Borla exhaust for my jc, maybe a nice intake. little subtle things for now:rolleyes:

Jangy
02-22-2006, 10:27 PM
I replaced the air filter and box with a K&N can. It MAY be getting an extra mile or 2 per gallon.

INTREPER
03-08-2006, 10:17 AM
Hey guys, new to the site, with some suggestions.

Remove the snorkel going to the air box. It's very restricted. Then replace your stock air filter with a K&N filter.

I also installed a Magnaflow cat back system. Should be in production soon.

The hemis are very restricted both in and out. So once you un-cork them a little bit, they run great.

Faustus
03-08-2006, 10:50 AM
Jangy, I am wondering, if an air filter change would even have the slightest positive impact on the mpg used, would DC not do this from the start? After all, they spend much money to squeeze out the most performance with the mighest possible mpg ... if a reasonable cheap solution (changes to a filter and exhaust) would do this, why would they not do that? Most of these "solutions" seem to be gimmicks. To tune for more power with a worse mpg result, that I can understand but to have it both ways, I doubt it. Hence I understand Intreper's suggestions as they underline what I had posted as a link earlier about the Hemi engines in general.

donutz
03-08-2006, 12:57 PM
Hey guys, new to the site, with some suggestions.

Remove the snorkel going to the air box. It's very restricted. Then replace your stock air filter with a K&N filter.

I also installed a Magnaflow cat back system. Should be in production soon.

The hemis are very restricted both in and out. So once you un-cork them a little bit, they run great.
what is the magnaflow cat back system? where do you get it, our reserch it? thanks for the info

JoeTampa
03-08-2006, 01:13 PM
For that matter, where do you get a K&N filter??

pwloomi
03-08-2006, 05:46 PM
Cold, forced air usually makes more power than the hot air drawing off of the engine like you will when you remove the snorkel, so would it be a good thing to remove?

INTREPER
03-08-2006, 05:51 PM
Cold, forced air usually makes more power than the hot air drawing off of the engine like you will when you remove the snorkel, so would it be a good thing to remove?

It's a good thing to remove because its very restrictive. Before removing mine I ran a thermometer inside the box, with before, and after the removel readings. They were identicle. The only time you're going to suck in warmer air is when sitting at idle. Same effect will happen with any cold air intake. You want the colder air possible at acceleration and wide open throttle (WOT). YOu get the most benifit of it at those times.

With the snorkel removed, I gained 2.2 average miles according to the evic during 25 highway mile trips to work.
The butt dyno likes the removal of the snorkel a lot! :D

INTREPER
03-08-2006, 05:52 PM
For that matter, where do you get a K&N filter??

Go to ebay motors and run a search for "jeep commander air filter". You will then see a few vendors that offer the K&N filter. Its the same size filter element available for the Hemi Ram. I paid like $45 for mine if I remember right.

INTREPER
03-08-2006, 05:54 PM
what is the magnaflow cat back system? where do you get it, our reserch it? thanks for the info

A Magnaflow catback system is an exhaust system that replaces the factory exhaust set up from the cat converter to the back of the jeep. The factory set up is very restrictive, hence why the Jeep is so quiet.

I'm not sure if the kit is in production yet, but my truck was used for their product development. You can try calling them and seeing when the bolt up kit will be available. It makes driving this truck that much more fun :D

pwloomi
03-08-2006, 06:02 PM
It's a good thing to remove because its very restrictive. Before removing mine I ran a thermometer inside the box, with before, and after the removel readings. They were identicle. The only time you're going to suck in warmer air is when sitting at idle. Same effect will happen with any cold air intake. You want the colder air possible at acceleration and wide open throttle (WOT). YOu get the most benifit of it at those times.

With the snorkel removed, I gained 2.2 average miles according to the evic during 25 highway mile trips to work.
The butt dyno likes the removal of the snorkel a lot! :D

I may have to give it a shot. The comment that I made can be blamed on not knowing any better. Looks like you did your homework. Did you just disconnect it and put something (larger diameter) to replace it?

donutz
03-08-2006, 06:29 PM
A Magnaflow catback system is an exhaust system that replaces the factory exhaust set up from the cat converter to the back of the jeep. The factory set up is very restrictive, hence why the Jeep is so quiet.

I'm not sure if the kit is in production yet, but my truck was used for their product development. You can try calling them and seeing when the bolt up kit will be available. It makes driving this truck that much more fun :D
did the JC get much louder with the new kit? and what does it look like do you have any pics of the exhaust you can show us?

INTREPER
03-08-2006, 06:44 PM
I may have to give it a shot. The comment that I made can be blamed on not knowing any better. Looks like you did your homework. Did you just disconnect it and put something (larger diameter) to replace it?

I just removed the snorkel. The snorkel has a lot of shard bends and doesn't allow air to flow easily. I just left the hole as is on the front of the stock air box.
And no sweat on your comment buddy. I didn't take any offense to it. We're all here to learn about these awesome Jeeps ;)

INTREPER
03-08-2006, 06:46 PM
did the JC get much louder with the new kit? and what does it look like do you have any pics of the exhaust you can show us?

It got 25% louder I would estimate. Obviously, the harder you slam on the gas, the more noise you're going to make. But it's not obnoxious in my opinion. Also, at cruizing speeds, you can't even tell you have an exhaust. Specially with the windows rolled up.

I'll try and get some pics of the exhaust this week for ya.

INTREPER
03-08-2006, 06:53 PM
Here are some pics to give you an idea of how restrictive the snorkel is.

This shows the end that faces the grill. Notice the part that looks like it's broken? There's a cover that cuts 80% of that opening I broke off. This alone got me 1 mpg increase according to the EVIC.
http://dodgeintrepid.net/photopost/data/507/397front_of_snorkel.jpg

This is the end that connects into air box
http://dodgeintrepid.net/photopost/data/507/397snorkel_exit.jpg

The intake tube from the air box to the throttle body is also a little restrictive. Notice all the little chambers that connect to the main intake tube flow? Those are put there to make the flow of air quieter. They also rob HP due to them causing turbulance in the air flow.

http://dodgeintrepid.net/photopost/data/507/397bottom_of_second_airbox.jpg

Hope that helps.

INTREPER
03-08-2006, 06:56 PM
Here's what my intake looks like now temporarily until K&N releases their kit.

The white plastic tube enters all the way into the air box, by-passing the accordion tube. I used the accordian tube as a means to connect the pipe and the box.

http://dodgeintrepid.net/photopost/data/507/397front_of_intake.jpg
http://dodgeintrepid.net/photopost/data/515/397side_of_intake.jpg

samax8
03-08-2006, 07:52 PM
Does the stock intake system offer some protection when going thru water?

donutz
03-08-2006, 08:11 PM
is this the new intake?http://www.autoanything.com/products/product_gnn.aspx?p_id=1913&se=k&n_77_series_metal_intake_kit , but on the official K&N website they do not list a intake for an 06 JC

donutz
03-08-2006, 08:33 PM
on the magnaflow website it said they are making an exhaust for the hemi. Will they be making one for the V6 and the V8 (4.7L) as well or will it work on all of them?

pwloomi
03-08-2006, 09:46 PM
So the on the homemade intake, is that 3" PVC for the straight piece or is it something else?

SYCOHEMI
03-08-2006, 10:26 PM
I've got a Gibson Performance exhaust on my HEMI, and it sounds great. Not too loud, but definitely a big change from stock, which I could barely hear at all.

INTREPER
03-08-2006, 11:18 PM
So the on the homemade intake, is that 3" PVC for the straight piece or is it something else?

Yes, and a 90 degree elbow

INTREPER
03-08-2006, 11:19 PM
is this the new intake?http://www.autoanything.com/products/product_gnn.aspx?p_id=1913&se=k&n_77_series_metal_intake_kit , but on the official K&N website they do not list a intake for an 06 JC

I haven't seen one yet, but the shape seems about right.

INTREPER
03-08-2006, 11:20 PM
on the magnaflow website it said they are making an exhaust for the hemi. Will they be making one for the V6 and the V8 (4.7L) as well or will it work on all of them?

I imagine the same kit will work on all of them. Only diffrence is that each engine sounds a bit diffrent.

Todd Abbott
03-27-2006, 08:10 PM
I think the intake kit that was fabed out of PVC could be fabed very easy out of steel as it's only a single 90 degree bend, as for all that restricting ducting leading into the intake box I agree on removing it, it's typically there to quiet the engine down but it also chokes the motor, robbing performance and milage.

pwloomi
03-27-2006, 08:39 PM
So here is proof that taking off the snorkel improves mileage. The Commander had to go into the shop, so they gave us a 06 GC to drive. The GC had the same motor and weighs less, but it got about 2 mpg's less than my commander w/o the snorkel.

INTREPER
03-27-2006, 09:16 PM
I think the intake kit that was fabed out of PVC could be fabed very easy out of steel as it's only a single 90 degree bend, as for all that restricting ducting leading into the intake box I agree on removing it, it's typically there to quiet the engine down but it also chokes the motor, robbing performance and milage.

THe bend is more like an 85 degree angle. I'm telling you, that air box is restrictive!

Todd Abbott
03-28-2006, 01:34 PM
Still a pretty easy fab job at 85 degree's.

INTREPER
03-28-2006, 04:51 PM
Still a pretty easy fab job at 85 degree's.

I would think that doing an intake tube in metal, be it aluminum, etc., would transfer more air flow into the TB. Another idea would be to sleeve the pipe with ABS pipe or something. I've seen that done a lot and works very well from what i've heard.

chipw
03-29-2006, 01:52 PM
I replaced the air filter and box with a K&N can. It MAY be getting an extra mile or 2 per gallon.


Jangy,
Which filter did you use. I cant find where K&N sells a kit for the commander yet.

lumberjim
10-06-2006, 09:47 PM
which one?

this one? (http://www.knfilters.com/search/product.aspx?Prod=63-1549) $278.84 15.3 hp increase

or

this one? (http://www.knfilters.com/search/product.aspx?Prod=77-1549KP) $314.59 12.90 hp increase

lumberjim
10-06-2006, 10:02 PM
scroll down and listen to the 5.7L gr cher file. (http://www.magnaflow.com/04sound/04trucks.asp)

Chipster009
10-07-2006, 12:00 AM
Yummy!

Definitely my next mod.

AJGuy84
01-18-2008, 02:44 PM
I have been driving with my snorkel taken off for about 2 weeks now. My results are AMAZING!! On my XK Hemi, I had been regularly getting about 13-14mpg city, and 16-17mpg Highway. I am now amazed at my 17mpg average city, and upwards of 22mpg highway! I have noticed a little bit more power too...Not huge gains, but noticeable none-the-less. The only other mod I have done so far is a K&N replacement for stock air filter.

Removing the snorkel only took like 10 min...It just popped out of the air box. I am keeping it just in case I need it later, but I'm sure it is just going to keep collecting dust, because this mod is awesome!

cliffk82
01-18-2008, 05:43 PM
I have been driving with my snorkel taken off for about 2 weeks now. My results are AMAZING!! On my XK Hemi, I had been regularly getting about 13-14mpg city, and 16-17mpg Highway. I am now amazed at my 17mpg average city, and upwards of 22mpg highway! I have noticed a little bit more power too...Not huge gains, but noticeable none-the-less. The only other mod I have done so far is a K&N replacement for stock air filter.

Removing the snorkel only took like 10 min...It just popped out of the air box. I am keeping it just in case I need it later, but I'm sure it is just going to keep collecting dust, because this mod is awesome!

Any pics/tips on this snorkel removing for us auto illiterate folks?

cliffk82
01-18-2008, 05:44 PM
Also what is the purpose of the snorkel, and is it officially safe to take it off?

a49erFan
01-18-2008, 09:41 PM
Also what is the purpose of the snorkel, and is it officially safe to take it off?

Many of us are running CAI's and have all removed the snorkel, unless you are fording a lot of creeks & rivers you should not need it for your daily driver.

davebbq
01-20-2008, 10:25 PM
new to forum ...very nice pics

AJGuy84
01-21-2008, 04:25 AM
Any pics/tips on this snorkel removing for us auto illiterate folks?
I know it may sound complicated, but it really is SOOOOO simple.
It's as easy as 1, 2, 3:


1. Remove the grill:
Pop the hood and lift out the 6 or so black plastic push-in fasteners above where the radiator is. A screwdriver works well to pry up and lift out the middle part, then you can remove the outside part. Once all are removed, simply remove the grill.

2. Locate the Snorkel:
This will be located on the passenger side, and is the same color plastic as everything else. Grip it and wiggle it. It may come out easier than you think...if not, pull a little harder, as there are no fasteners holding it to your air box, ie. kinda like snap-together.

3. Replace the grill:
insert all the the retaining part of the push in fasteners first, and then push in the center piece. If your thumbs are sore from pulling them out, use the back of a screwdriver to gently tap them back in.

Voila! Enjoy the benefits the Chrysler has been denying you! Make sure to reset your MPG meter on your dash, and if you have been driving for a long time, disconnect your negative battery cable for about 30 seconds to wipe out your computer's memory of your driving style (don't worry, your radio presets will be safe.)


Hope this helps! I'll edit with some pictures when I can snag the beast from Beauty, aka my wife.
-AJ

RedCommander
01-21-2008, 08:24 AM
Also what is the purpose of the snorkel, and is it officially safe to take it off?

Sound dampening.

cliffk82
01-23-2008, 09:36 AM
Just finished this mod. It was very easy thanks to AJ's instructions. I have no idea how much it will help on mileage...i'll give an update after the next tank of gas.

Commander_Rulez
01-23-2008, 10:39 AM
I did this mod back in Sept, now that I'm thinking of it is this car wash safe ie touchless car washes spray the front grill a few times? I haven't checked it since its so cold outside.

cliffk82
01-23-2008, 11:03 AM
Have you noticed a MPG difference?

I did this mod back in Sept, now that I'm thinking of it is this car wash safe ie touchless car washes spray the front grill a few times? I haven't checked it since its so cold outside.

Commander_Rulez
01-24-2008, 10:21 AM
Have you noticed a MPG difference?

I noticed a small increase in mileage maybe 1-.5mpg better I think it has more of an effect on hiway mileage then city traffic.

mikenaf123
01-05-2010, 08:59 AM
Is this touchless carwash safe?

louie61571
01-08-2010, 02:51 PM
Anyone have any pics of the snorkel removed.I'd like to try this mod when it gets warmer and don't know what the snorkel is.Thanks

tawoody
01-08-2010, 04:16 PM
I've never seen one for a car before but for motorcycles you can buy a water-resistant cover that goes over exposed air filters for the purpose of keeping water out of the filter. I suppose if you put one over an exposed CAI it would help in car washes or the monthly engine rinse down.

dmoser
01-23-2010, 03:32 PM
Is this touchless carwash safe?

Should be fine. The opening on the airbox sits behind the headlight and even if some water gets it, there is a provision at the bottom of the airbox for the water to escape.

Here are some pics of the snorkel.

As it is positioned behind the grill when installed:

http://i196.photobucket.com/albums/aa111/101kpa/SDC11915-1.jpg

The end that fits into the airbox:

http://i196.photobucket.com/albums/aa111/101kpa/SDC11914-1.jpg

Here are two pictures that show an integrated sound chamber for sound dampening, notice the small acoustic hole on the inside of the tube:

http://i196.photobucket.com/albums/aa111/101kpa/SDC11916-1.jpg

and the sub chamber:

http://i196.photobucket.com/albums/aa111/101kpa/SDC11917-1.jpg

hogwash
01-23-2010, 04:16 PM
I just spent 10 minutes and took off the snorkel. I'm not how this is going to increase my MPG but figured I would give it a shot. The snorkel seems to be pretty free flowing so I am not sure how much of an increase it will give me. I track my MPG so I will report back after a few fill-ups.

dmoser
01-23-2010, 06:09 PM
I just spent 10 minutes and took off the snorkel. I'm not how this is going to increase my MPG but figured I would give it a shot. The snorkel seems to be pretty free flowing so I am not sure how much of an increase it will give me. I track my MPG so I will report back after a few fill-ups.

If there is no performance gain, at least it sounds cool at WOT.

hogwash
01-31-2010, 11:48 AM
So far, I have filled up the gas tank twice since removing the snorkel. There has been no increase in MPG. Also, WOT noise is pretty much the same as before. I will give it a few more fill-ups before I decide to return it back to stock.

Also, I am not sure how to determine if there is any "performance gain" but on my way home from work, I climb a large hill on the highway. I attempt to climb the hill and stay in overdrive. I usually hit the hill at 75 mph and attempt to keep the accelerator pressed so that it does not drop down a gear and also so that my speed does not drop under 65 mph. I have noticed the same results with and without the snorkel. I'm assuming that if there was a performance gain, I might be able to hold the 65+ mph climbing the hill in 5th gear.

dmoser
02-05-2010, 08:57 PM
Also, WOT noise is pretty much the same as before.

Mine is a bit louder and deeper as a result of a K&N filter, probably.

MomsR/T
02-08-2010, 11:36 AM
SOmething to consider - you might find that the air filter is the same size on the 4.7 as it is on the 5.7. WHat this tells me is either that the air filter on the 4.7 is too big or the air filter on the 5.7 is too small.

I am going to presume that the air filter on the 5.7 is too small given my experience on the car side of this motor.

Given that it is too small for the 5.7 can the same be said for the 4.7? Maybe so maybe not however I do not believe that you'll see the same benefit equally between the 2 different sized motors given their vastly different displacements.

THe snorkle removement come straight out of the LX (car) world and we quantified and qualified that it made real horse power. I don't know if the "hill method" of testing performance gain counts or not rather we used dyno's.

ALl of that can be read on the HEMI car forums (and there are millions of them now).

THe bottomline is:

Take off the restrictive snorkle
Use a CAI whose tube is AT LEAST the same inner diameter as the TB
Use the biggest filter you can
SMaller engine may need not apply
THe more power you make the more air you'll need

AcidCold
02-13-2010, 02:47 PM
I wanted something else for my low end power on my 4.7 to work well with my Superchips, flowmaster exhaust and AFE+Airaid system, the answer was a ported and polished throttle body.
The stock 4.7 TB is 65mm the new one is 68mm.
I have yet to install it but others have positive feedback, we shall see.

http://i190.photobucket.com/albums/z216/Acidcold/CIMG0712.jpg
http://i190.photobucket.com/albums/z216/Acidcold/CIMG0710.jpg
http://i190.photobucket.com/albums/z216/Acidcold/CIMG0711.jpg

dmoser
02-27-2010, 07:36 PM
There has been no increase in MPG.

Same here. Any power gain would be very hard to quantify on the butt dyno, too.

dmoser
03-03-2010, 06:58 PM
I wanted something else for my low end power on my 4.7 to work well with my Superchips, flowmaster exhaust and AFE+Airaid system, the answer was a ported and polished throttle body.
The stock 4.7 TB is 65mm the new one is 68mm.
I have yet to install it but others have positive feedback, we shall see.


More info on the TB- source, cost? Thanks

awags
03-14-2010, 12:31 PM
Jangy, I am wondering, if an air filter change would even have the slightest positive impact on the mpg used, would DC not do this from the start? After all, they spend much money to squeeze out the most performance with the mighest possible mpg ... if a reasonable cheap solution (changes to a filter and exhaust) would do this, why would they not do that? Most of these "solutions" seem to be gimmicks. To tune for more power with a worse mpg result, that I can understand but to have it both ways, I doubt it. Hence I understand Intreper's suggestions as they underline what I had posted as a link earlier about the Hemi engines in general.

Not to sound like a know it all, but the factory makes the intake and exhaust mainly just to be quiet and perform adequately. Putting on a cold air intake and exhaust will make the motor perform better and you will get better mpg's. I have done it on the last 3 vehicles I have owned and have seen significant improvements in both hp and mpg's. Also if you're already changing out the exhaust put in a high flow catalytic converter too. All these changes are well worth the money.

USMCMP
03-14-2010, 01:48 PM
I didnt think of the high flow cat thing a week ago when I got my exhaust done but good thinking. I have also heard that exhaust and CAI gains are insignificant until paired with a chip or programmer. Have other people heard this also? What about unplugging battery to reset computer so it adjusts to new mods?

dmoser
03-23-2010, 08:02 PM
I didnt think of the high flow cat thing a week ago when I got my exhaust done but good thinking. I have also heard that exhaust and CAI gains are insignificant until paired with a chip or programmer. Have other people heard this also? What about unplugging battery to reset computer so it adjusts to new mods?

You will still get a benefit with modern EFI systems. The fuel trims will adjust faster if you reset the ECU, but they will also adjust to the changes if you don't, albeit at a slower pace.

I work in the emissions industry as an engineer. The pressure drop of a modern catalytic converter really isn't that much, to be honest with you. You might see some gains with a "high flow" converter as a cumulative effect w/other exhaust modifications, but I really don't think it is worth the cost.

AcidCold
03-26-2010, 09:20 PM
More info on the TB- source, cost? Thanks

Not much to say really, i will say that my throttle is so much smoother and responsive with the new port and polish.
I paid $120 fort eh service and a new TB from a vendor on another forum.
Worth every penny if you have a true cold air intake and cat-back with a tune.

louie61571
04-19-2010, 11:49 PM
I did the snorkel mod today with K&N drop in air filter.I'll try it for a month and see if it makes a difference.If not I'll put the snorkel back

Shocker
04-29-2010, 01:23 PM
has anyone tried using a cherry bomb or glasspacks ...i think its the muffler that is red and sorta like a plain tube ..i think it would sound killer but will it help any?:rofl:

VMI11
05-13-2010, 03:46 PM
Shocker- I'm not sure how those would sound on a 3.7 but I actually just had a magnaflow put on my 3.7 today and it sounds awesome. I'll keep everyone posted as far as gas milage/power increases but so far I love it. I was looking the same direction you were but ended up going with a magnaflow because of a video/sound clip someone put up who had a 3.7. good luck!

bp73
05-13-2010, 04:43 PM
Not much to say really, i will say that my throttle is so much smoother and responsive with the new port and polish.
I paid $120 fort eh service and a new TB from a vendor on another forum.
Worth every penny if you have a true cold air intake and cat-back with a tune.
Did you notice any of the low-end enhancement you were looking for?

ChrisWK
08-04-2010, 08:38 PM
Hello,
I installed a AFE intake and 180 stat on my hemi,It feels quicker.

AcidCold
08-09-2010, 08:38 PM
Did you notice any of the low-end enhancement you were looking for?

I did, this upgrade is very well worth it if you have a CAI and a cat-back.

fur-ball
08-09-2010, 11:26 PM
has anyone tried using a cherry bomb or glasspacks ...i think its the muffler that is red and sorta like a plain tube ..i think it would sound killer but will it help any?:rofl:

I have the 3.7 with a cherry bomb.
It sounds a lot better.
I'll try to post a sound clip tomorrow.

2007JeepCommanderLimited
11-09-2012, 09:18 AM
Ok guys I have $3,000 to increase my horsepower in my completly stock 2007 Commander Limited edition with a 3.7 Liter V6. I know nothing about mods so if you where in this situation what is the biggest bang for the buck without distroying the engine or overworking it... Any thoughts on how the 3K should be spent?

karmatt
11-15-2012, 08:00 AM
If i had $3000 to blow on it I would go with port and polish job on heads, intake, and throttle body($300-$700 plus labor), a new diablo tuner($400 +/-), Snorkel setup ($?), FULL exhaust ($1500 +/-)...... BEAST!!!:domotwak:

commander67
11-20-2012, 10:15 PM
I recently purchased a 2009 4.7 Limited bone stock "for the wife" I was wanting to put a k&n drop filter in it but I also was fartin around the idea of a cold air intake. what would be better and what are the downsides to both. also what is a good exhaust i feel bad for the motor like its starving for air.