H3 i5 HP&MPG Gains With Your Mods
Thread Starter
|
Junior Member
Joined: Feb 2020
Posts: 15
H3 i5 HP&MPG Gains With Your Mods
Good Morning All,
Just curious to see what gains people here have seen with their mods on the i5 Hummer h3 engine. If you could list all your mods and where your HP and MPG currently stand, thank you!
Just curious to see what gains people here have seen with their mods on the i5 Hummer h3 engine. If you could list all your mods and where your HP and MPG currently stand, thank you!
Last edited by Hummerbird; Mar 6, 2020 at 08:36 PM.
Super Moderator
Joined: Jul 2007
Posts: 13,083
From: Boat Town USA MI
I no longer have my 07, but it had all the performance and off road mods on MTZ 305s, weighed in close to 6000# with me and in it (put it on the local landscape company truck scale). That was one of the best truck I ever owned and I had it 12 years.
Performance: Air Doc Intake with AFE Pro-Dry Filter, Port/Polish TB, PCM of NC PCM Tune and Efan conversion, MagnaFlow Cat Back Exhaust and CFS Aluminum Radiator. Got no idea what the end HP/TQ was, no point in figuring it out. It ran strong and even made some FS V8 Pickups look silly in sand drags when they found out they were done in by an aluminum 5 banger. Not the grunt of a stock Alpha, but pretty stout with better MPG.
MPG was improved. Biggest thing is drive with slow easy starts and keep the Eway speed to 75 or less. I saw a high of 19.5 all highway in the summer in calm conditions with tires at 40PSI on one trip, regularly managed about 16.5+ combined. If it did not have a BA Winch bumper and rock rails, probably would have done better MPG without that extra weight, and even better with 285s instead of 305s. Forget all that as soon as the wind starts to blow, H3s are a brick when bucking headwinds.
I can also say that I made a 150 mile run couple summers back with two 12' kayaks on roof racks at 70MPH and got 14MPG pushing it all through the wind.
Performance: Air Doc Intake with AFE Pro-Dry Filter, Port/Polish TB, PCM of NC PCM Tune and Efan conversion, MagnaFlow Cat Back Exhaust and CFS Aluminum Radiator. Got no idea what the end HP/TQ was, no point in figuring it out. It ran strong and even made some FS V8 Pickups look silly in sand drags when they found out they were done in by an aluminum 5 banger. Not the grunt of a stock Alpha, but pretty stout with better MPG.
MPG was improved. Biggest thing is drive with slow easy starts and keep the Eway speed to 75 or less. I saw a high of 19.5 all highway in the summer in calm conditions with tires at 40PSI on one trip, regularly managed about 16.5+ combined. If it did not have a BA Winch bumper and rock rails, probably would have done better MPG without that extra weight, and even better with 285s instead of 305s. Forget all that as soon as the wind starts to blow, H3s are a brick when bucking headwinds.
I can also say that I made a 150 mile run couple summers back with two 12' kayaks on roof racks at 70MPH and got 14MPG pushing it all through the wind.
Member
Joined: Jan 2020
Posts: 51
From: Colorado
06, cold air intake, cat back exhaust, 33s, baiscally stock i get 18.6 but thats running colorado mountains at 9000 ft. im at 3-5 over posted limit usually when its safe.
just installed my new pcm from pcm nc ill see what it adds or takes away this week.
just installed my new pcm from pcm nc ill see what it adds or takes away this week.
Thread Starter
|
Junior Member
Joined: Feb 2020
Posts: 15
Nice!! Please share the results of your PCM tune from NC PCM. Curious to see how that turns out as well, I always hear good stuff about them and PCMforLess
Thread Starter
|
Junior Member
Joined: Feb 2020
Posts: 15
I no longer have my 07, but it had all the performance and off road mods on MTZ 305s, weighed in close to 6000# with me and in it (put it on the local landscape company truck scale). That was one of the best truck I ever owned and I had it 12 years.
Performance: Air Doc Intake with AFE Pro-Dry Filter, Port/Polish TB, PCM of NC PCM Tune and Efan conversion, MagnaFlow Cat Back Exhaust and CFS Aluminum Radiator. Got no idea what the end HP/TQ was, no point in figuring it out. It ran strong and even made some FS V8 Pickups look silly in sand drags when they found out they were done in by an aluminum 5 banger. Not the grunt of a stock Alpha, but pretty stout with better MPG.
MPG was improved. Biggest thing is drive with slow easy starts and keep the Eway speed to 75 or less. I saw a high of 19.5 all highway in the summer in calm conditions with tires at 40PSI on one trip, regularly managed about 16.5+ combined. If it did not have a BA Winch bumper and rock rails, probably would have done better MPG without that extra weight, and even better with 285s instead of 305s. Forget all that as soon as the wind starts to blow, H3s are a brick when bucking headwinds.
I can also say that I made a 150 mile run couple summers back with two 12' kayaks on roof racks at 70MPH and got 14MPG pushing it all through the wind.
Performance: Air Doc Intake with AFE Pro-Dry Filter, Port/Polish TB, PCM of NC PCM Tune and Efan conversion, MagnaFlow Cat Back Exhaust and CFS Aluminum Radiator. Got no idea what the end HP/TQ was, no point in figuring it out. It ran strong and even made some FS V8 Pickups look silly in sand drags when they found out they were done in by an aluminum 5 banger. Not the grunt of a stock Alpha, but pretty stout with better MPG.
MPG was improved. Biggest thing is drive with slow easy starts and keep the Eway speed to 75 or less. I saw a high of 19.5 all highway in the summer in calm conditions with tires at 40PSI on one trip, regularly managed about 16.5+ combined. If it did not have a BA Winch bumper and rock rails, probably would have done better MPG without that extra weight, and even better with 285s instead of 305s. Forget all that as soon as the wind starts to blow, H3s are a brick when bucking headwinds.
I can also say that I made a 150 mile run couple summers back with two 12' kayaks on roof racks at 70MPH and got 14MPG pushing it all through the wind.
Member
Joined: Jan 2020
Posts: 51
From: Colorado
Have had the PCM tune installed for a couple of days now.
1. I had them adjust the idle up a bit. sits at about 750 rpms. this made a nice change in the driveability. This alone makes the tune worth every penny. smoother idle, smoother off the line, no rpm dive as i come to a light. this should have been the factory setting.
2. i had them do an 87 octane tune, so not really a heavy perfomance tune, but where I am 87 octane is midgrade and at 8700+ ft altitudes, pinging can be a problem with aggressive changes in timing. rig is defintiely smoother, quieter and faster off the line (not a race car). Top end I did not see a huge improvement although after the third day I did gain 3 miles per hour going up one of my local hills. About 3 miles of 7-8 percent grade. Before third gear would maintain about 48-49 mph without downshifting into 2nd gear. Yesterday the h3 hit 51 in third on the same hill. Weird cause earlier in the day it stalled out again at 48ish. no real difference in temp or wind so not sure why it went faster. I'll have to see if that is a consistant change in power.
3. temp guage reads a bit cooler, sitting closer to 1/2 rather than 5/8s
4. I also had them bypass the passlock system. This saved me from having to bypass the system for a remote start.
5. I put the rig through emissions yesterday with the tune installed, passed colorado emissions with no issues.
overall I am happy with PCM of NC, I over nighted the computer to them on a Monday, they turned it around in a day and it was back in my hands on Friday.
Thread Starter
|
Junior Member
Joined: Feb 2020
Posts: 15
Have had the PCM tune installed for a couple of days now.
1. I had them adjust the idle up a bit. sits at about 750 rpms. this made a nice change in the driveability. This alone makes the tune worth every penny. smoother idle, smoother off the line, no rpm dive as i come to a light. this should have been the factory setting.
2. i had them do an 87 octane tune, so not really a heavy perfomance tune, but where I am 87 octane is midgrade and at 8700+ ft altitudes, pinging can be a problem with aggressive changes in timing. rig is defintiely smoother, quieter and faster off the line (not a race car). Top end I did not see a huge improvement although after the third day I did gain 3 miles per hour going up one of my local hills. About 3 miles of 7-8 percent grade. Before third gear would maintain about 48-49 mph without downshifting into 2nd gear. Yesterday the h3 hit 51 in third on the same hill. Weird cause earlier in the day it stalled out again at 48ish. no real difference in temp or wind so not sure why it went faster. I'll have to see if that is a consistant change in power.
3. temp guage reads a bit cooler, sitting closer to 1/2 rather than 5/8s
4. I also had them bypass the passlock system. This saved me from having to bypass the system for a remote start.
5. I put the rig through emissions yesterday with the tune installed, passed colorado emissions with no issues.
overall I am happy with PCM of NC, I over nighted the computer to them on a Monday, they turned it around in a day and it was back in my hands on Friday.
1. I had them adjust the idle up a bit. sits at about 750 rpms. this made a nice change in the driveability. This alone makes the tune worth every penny. smoother idle, smoother off the line, no rpm dive as i come to a light. this should have been the factory setting.
2. i had them do an 87 octane tune, so not really a heavy perfomance tune, but where I am 87 octane is midgrade and at 8700+ ft altitudes, pinging can be a problem with aggressive changes in timing. rig is defintiely smoother, quieter and faster off the line (not a race car). Top end I did not see a huge improvement although after the third day I did gain 3 miles per hour going up one of my local hills. About 3 miles of 7-8 percent grade. Before third gear would maintain about 48-49 mph without downshifting into 2nd gear. Yesterday the h3 hit 51 in third on the same hill. Weird cause earlier in the day it stalled out again at 48ish. no real difference in temp or wind so not sure why it went faster. I'll have to see if that is a consistant change in power.
3. temp guage reads a bit cooler, sitting closer to 1/2 rather than 5/8s
4. I also had them bypass the passlock system. This saved me from having to bypass the system for a remote start.
5. I put the rig through emissions yesterday with the tune installed, passed colorado emissions with no issues.
overall I am happy with PCM of NC, I over nighted the computer to them on a Monday, they turned it around in a day and it was back in my hands on Friday.
Member
Joined: Jan 2020
Posts: 51
From: Colorado
I cannot say whether I gained any gas mileage, but even just coming home from a grocery trip i have pretty heavy grades and im doing 60 plus in third most of the time, so gas mileage improvements will hide for sure
Thread
Thread Starter
Forum
Replies
Last Post
KA H2
PRIVATE For Sale / Trade Classifieds
1
Sep 1, 2013 07:07 PM
T REX
PRIVATE For Sale / Trade Classifieds
15
Mar 8, 2008 02:05 PM