Engine power
#11
11-05-2017, 12:53 AM
On mine - I started with the basics and is pretty much exactly as I said.
ACDelco spark plugs. Do NOT use any other plugs. Get ACDelco #41-110 plugs.
I went with Taylor 409 spark plug wires (79205)
Get the right cleaner (CRC makes a spray cleaner for it) for the MAF
I got an Airaid air intake tube. I kept the stock air box as it is actually already an excellent very well design that pulls air from the fender while most all aftermarket cold air intakes pull air from the exact same place and many from also under the hood. I also have an Airaid performance air filter which flows a good bit better than the stock filter.
If any check engine lights or codes - you need to find out what they are and address those issues.
Remove and carefully clean the throttle body.
Cleaning the inside of the intake manifold is a pretty involved procedure and I'd not recommend that unless you really want to as it requires new gaskets and a lot of work. I only did because I needed to replace the knock sensors which require pulling the intake anyways.
Get a handheld tuner. My personal choice for the do it your-selfer would be a Diablosport Intune. That has a few very good stock tunes and when you are ready you can lookup Lewis (google diablosport lewis custom tune) and pay him to do a custom tune up. That will really wake things up as well as dramatically improve shifting.
Next bigger step is the exhaust. I went with the somewhat lower cost brand OBX from an eBay seller. Its the full stainless long tube set with the high flow cats. Then I lucked out and found a new old stock GM Performance (its made by Borla and is their touring kit) parts stainless cat-back exhaust kit. Both kits together replace the entire exhaust system end to end. When I did the exhaust I also spend a bit extra and went ahead and replaced both of the upstream O2 sensors.
All of the above - I've probably spent $1500 or so doing but I saved a good bit on that GM Performance Parts exhaust bit.
I do have the Diablosport Intune and am running the performance tune. Keep in mind, with a premium performance tune or if you get a supercharger you will need to always run premium fuel. You can get severe spark knock if you run regular gas which can cause major engine damage. If you do not want to run premium a supercharger will be out but you can still run a performance tune, just needs to be one that has the timing cut back a little so you do not get any knocking. A good custom tune also modifies the transmission shifting significantly as well.
I figure with everything I've done above and running the premium performance tune that I've probably picked up around 60 to 75 HP overall. Of course the basic tuneup does not add any horsepower per say, that just helps restore the original power that has declined from the old components. The biggest gains came from the free flowing exhaust system, better flowing air intake, and the custom tune. The air intake by itself will realistically only gain you maybe 3 to 10 HP depending on what all you get. The header kit really needs everything after the cats as well to fully realize the gains from that which are probably around 25 HP for the header kit by itself and closer to 35 HP if you replace it all end to end like I did. The major improvements in airflow both coming in and going out combined with (as well as running as good as it can from the tuneup) a custom tune are big improvements.
ACDelco spark plugs. Do NOT use any other plugs. Get ACDelco #41-110 plugs.
I went with Taylor 409 spark plug wires (79205)
Get the right cleaner (CRC makes a spray cleaner for it) for the MAF
I got an Airaid air intake tube. I kept the stock air box as it is actually already an excellent very well design that pulls air from the fender while most all aftermarket cold air intakes pull air from the exact same place and many from also under the hood. I also have an Airaid performance air filter which flows a good bit better than the stock filter.
If any check engine lights or codes - you need to find out what they are and address those issues.
Remove and carefully clean the throttle body.
Cleaning the inside of the intake manifold is a pretty involved procedure and I'd not recommend that unless you really want to as it requires new gaskets and a lot of work. I only did because I needed to replace the knock sensors which require pulling the intake anyways.
Get a handheld tuner. My personal choice for the do it your-selfer would be a Diablosport Intune. That has a few very good stock tunes and when you are ready you can lookup Lewis (google diablosport lewis custom tune) and pay him to do a custom tune up. That will really wake things up as well as dramatically improve shifting.
Next bigger step is the exhaust. I went with the somewhat lower cost brand OBX from an eBay seller. Its the full stainless long tube set with the high flow cats. Then I lucked out and found a new old stock GM Performance (its made by Borla and is their touring kit) parts stainless cat-back exhaust kit. Both kits together replace the entire exhaust system end to end. When I did the exhaust I also spend a bit extra and went ahead and replaced both of the upstream O2 sensors.
All of the above - I've probably spent $1500 or so doing but I saved a good bit on that GM Performance Parts exhaust bit.
I do have the Diablosport Intune and am running the performance tune. Keep in mind, with a premium performance tune or if you get a supercharger you will need to always run premium fuel. You can get severe spark knock if you run regular gas which can cause major engine damage. If you do not want to run premium a supercharger will be out but you can still run a performance tune, just needs to be one that has the timing cut back a little so you do not get any knocking. A good custom tune also modifies the transmission shifting significantly as well.
I figure with everything I've done above and running the premium performance tune that I've probably picked up around 60 to 75 HP overall. Of course the basic tuneup does not add any horsepower per say, that just helps restore the original power that has declined from the old components. The biggest gains came from the free flowing exhaust system, better flowing air intake, and the custom tune. The air intake by itself will realistically only gain you maybe 3 to 10 HP depending on what all you get. The header kit really needs everything after the cats as well to fully realize the gains from that which are probably around 25 HP for the header kit by itself and closer to 35 HP if you replace it all end to end like I did. The major improvements in airflow both coming in and going out combined with (as well as running as good as it can from the tuneup) a custom tune are big improvements.
#12
11-05-2017, 09:08 AM
On mine - I started with the basics and is pretty much exactly as I said.
ACDelco spark plugs. Do NOT use any other plugs. Get ACDelco #41-110 plugs.
I went with Taylor 409 spark plug wires (79205)
Get the right cleaner (CRC makes a spray cleaner for it) for the MAF
I got an Airaid air intake tube. I kept the stock air box as it is actually already an excellent very well design that pulls air from the fender while most all aftermarket cold air intakes pull air from the exact same place and many from also under the hood. I also have an Airaid performance air filter which flows a good bit better than the stock filter.
If any check engine lights or codes - you need to find out what they are and address those issues.
Remove and carefully clean the throttle body.
Cleaning the inside of the intake manifold is a pretty involved procedure and I'd not recommend that unless you really want to as it requires new gaskets and a lot of work. I only did because I needed to replace the knock sensors which require pulling the intake anyways.
Get a handheld tuner. My personal choice for the do it your-selfer would be a Diablosport Intune. That has a few very good stock tunes and when you are ready you can lookup Lewis (google diablosport lewis custom tune) and pay him to do a custom tune up. That will really wake things up as well as dramatically improve shifting.
Next bigger step is the exhaust. I went with the somewhat lower cost brand OBX from an eBay seller. Its the full stainless long tube set with the high flow cats. Then I lucked out and found a new old stock GM Performance (its made by Borla and is their touring kit) parts stainless cat-back exhaust kit. Both kits together replace the entire exhaust system end to end. When I did the exhaust I also spend a bit extra and went ahead and replaced both of the upstream O2 sensors.
All of the above - I've probably spent $1500 or so doing but I saved a good bit on that GM Performance Parts exhaust bit.
I do have the Diablosport Intune and am running the performance tune. Keep in mind, with a premium performance tune or if you get a supercharger you will need to always run premium fuel. You can get severe spark knock if you run regular gas which can cause major engine damage. If you do not want to run premium a supercharger will be out but you can still run a performance tune, just needs to be one that has the timing cut back a little so you do not get any knocking. A good custom tune also modifies the transmission shifting significantly as well.
I figure with everything I've done above and running the premium performance tune that I've probably picked up around 60 to 75 HP overall. Of course the basic tuneup does not add any horsepower per say, that just helps restore the original power that has declined from the old components. The biggest gains came from the free flowing exhaust system, better flowing air intake, and the custom tune. The air intake by itself will realistically only gain you maybe 3 to 10 HP depending on what all you get. The header kit really needs everything after the cats as well to fully realize the gains from that which are probably around 25 HP for the header kit by itself and closer to 35 HP if you replace it all end to end like I did. The major improvements in airflow both coming in and going out combined with (as well as running as good as it can from the tuneup) a custom tune are big improvements.
ACDelco spark plugs. Do NOT use any other plugs. Get ACDelco #41-110 plugs.
I went with Taylor 409 spark plug wires (79205)
Get the right cleaner (CRC makes a spray cleaner for it) for the MAF
I got an Airaid air intake tube. I kept the stock air box as it is actually already an excellent very well design that pulls air from the fender while most all aftermarket cold air intakes pull air from the exact same place and many from also under the hood. I also have an Airaid performance air filter which flows a good bit better than the stock filter.
If any check engine lights or codes - you need to find out what they are and address those issues.
Remove and carefully clean the throttle body.
Cleaning the inside of the intake manifold is a pretty involved procedure and I'd not recommend that unless you really want to as it requires new gaskets and a lot of work. I only did because I needed to replace the knock sensors which require pulling the intake anyways.
Get a handheld tuner. My personal choice for the do it your-selfer would be a Diablosport Intune. That has a few very good stock tunes and when you are ready you can lookup Lewis (google diablosport lewis custom tune) and pay him to do a custom tune up. That will really wake things up as well as dramatically improve shifting.
Next bigger step is the exhaust. I went with the somewhat lower cost brand OBX from an eBay seller. Its the full stainless long tube set with the high flow cats. Then I lucked out and found a new old stock GM Performance (its made by Borla and is their touring kit) parts stainless cat-back exhaust kit. Both kits together replace the entire exhaust system end to end. When I did the exhaust I also spend a bit extra and went ahead and replaced both of the upstream O2 sensors.
All of the above - I've probably spent $1500 or so doing but I saved a good bit on that GM Performance Parts exhaust bit.
I do have the Diablosport Intune and am running the performance tune. Keep in mind, with a premium performance tune or if you get a supercharger you will need to always run premium fuel. You can get severe spark knock if you run regular gas which can cause major engine damage. If you do not want to run premium a supercharger will be out but you can still run a performance tune, just needs to be one that has the timing cut back a little so you do not get any knocking. A good custom tune also modifies the transmission shifting significantly as well.
I figure with everything I've done above and running the premium performance tune that I've probably picked up around 60 to 75 HP overall. Of course the basic tuneup does not add any horsepower per say, that just helps restore the original power that has declined from the old components. The biggest gains came from the free flowing exhaust system, better flowing air intake, and the custom tune. The air intake by itself will realistically only gain you maybe 3 to 10 HP depending on what all you get. The header kit really needs everything after the cats as well to fully realize the gains from that which are probably around 25 HP for the header kit by itself and closer to 35 HP if you replace it all end to end like I did. The major improvements in airflow both coming in and going out combined with (as well as running as good as it can from the tuneup) a custom tune are big improvements.
Why do you say only use AC Delco plugs?
#14
11-05-2017, 11:25 AM
Do so searches online and read any number of forums for GM trucks (and cars) with GM LS engines and you will see almost every time that people get much better performance and long lasting plugs using the factory spec ACDelco plugs.
I tried some others many years ago on my 99 GMC (5.3L) and it just felt sluggish and weak. Started looking online and ended up on perfomancetrucks and asked while stating that I had recently done a tuneup and literally about 20 replies were what plugs did I install and if not ACDelco to get them out asap and put the right ones in. I did and lo and behold it ran great after.
That being said if you search online for the best plugs for LS engines the NGK plugs are also very popular but many seem to say they do not last as long and a big part of the popularity is because they are a bit less expensive than the ACDelco plugs. For the most part those are the two you will see recommended. The factory spec ACDelco plugs are generally good for 100,000 miles which is a plus for me as changing them is kind of a pain. That and they will work 100% perfect every time which is why they are the only ones I recommend for others to us.
I tried some others many years ago on my 99 GMC (5.3L) and it just felt sluggish and weak. Started looking online and ended up on perfomancetrucks and asked while stating that I had recently done a tuneup and literally about 20 replies were what plugs did I install and if not ACDelco to get them out asap and put the right ones in. I did and lo and behold it ran great after.
That being said if you search online for the best plugs for LS engines the NGK plugs are also very popular but many seem to say they do not last as long and a big part of the popularity is because they are a bit less expensive than the ACDelco plugs. For the most part those are the two you will see recommended. The factory spec ACDelco plugs are generally good for 100,000 miles which is a plus for me as changing them is kind of a pain. That and they will work 100% perfect every time which is why they are the only ones I recommend for others to us.
#15
11-06-2017, 02:48 AM
On mine - I started with the basics and is pretty much exactly as I said.
ACDelco spark plugs. Do NOT use any other plugs. Get ACDelco #41-110 plugs.
I went with Taylor 409 spark plug wires (79205)
Get the right cleaner (CRC makes a spray cleaner for it) for the MAF
I got an Airaid air intake tube. I kept the stock air box as it is actually already an excellent very well design that pulls air from the fender while most all aftermarket cold air intakes pull air from the exact same place and many from also under the hood. I also have an Airaid performance air filter which flows a good bit better than the stock filter.
If any check engine lights or codes - you need to find out what they are and address those issues.
Remove and carefully clean the throttle body.
Cleaning the inside of the intake manifold is a pretty involved procedure and I'd not recommend that unless you really want to as it requires new gaskets and a lot of work. I only did because I needed to replace the knock sensors which require pulling the intake anyways.
Get a handheld tuner. My personal choice for the do it your-selfer would be a Diablosport Intune. That has a few very good stock tunes and when you are ready you can lookup Lewis (google diablosport lewis custom tune) and pay him to do a custom tune up. That will really wake things up as well as dramatically improve shifting.
Next bigger step is the exhaust. I went with the somewhat lower cost brand OBX from an eBay seller. Its the full stainless long tube set with the high flow cats. Then I lucked out and found a new old stock GM Performance (its made by Borla and is their touring kit) parts stainless cat-back exhaust kit. Both kits together replace the entire exhaust system end to end. When I did the exhaust I also spend a bit extra and went ahead and replaced both of the upstream O2 sensors.
All of the above - I've probably spent $1500 or so doing but I saved a good bit on that GM Performance Parts exhaust bit.
I do have the Diablosport Intune and am running the performance tune. Keep in mind, with a premium performance tune or if you get a supercharger you will need to always run premium fuel. You can get severe spark knock if you run regular gas which can cause major engine damage. If you do not want to run premium a supercharger will be out but you can still run a performance tune, just needs to be one that has the timing cut back a little so you do not get any knocking. A good custom tune also modifies the transmission shifting significantly as well.
I figure with everything I've done above and running the premium performance tune that I've probably picked up around 60 to 75 HP overall. Of course the basic tuneup does not add any horsepower per say, that just helps restore the original power that has declined from the old components. The biggest gains came from the free flowing exhaust system, better flowing air intake, and the custom tune. The air intake by itself will realistically only gain you maybe 3 to 10 HP depending on what all you get. The header kit really needs everything after the cats as well to fully realize the gains from that which are probably around 25 HP for the header kit by itself and closer to 35 HP if you replace it all end to end like I did. The major improvements in airflow both coming in and going out combined with (as well as running as good as it can from the tuneup) a custom tune are big improvements.
ACDelco spark plugs. Do NOT use any other plugs. Get ACDelco #41-110 plugs.
I went with Taylor 409 spark plug wires (79205)
Get the right cleaner (CRC makes a spray cleaner for it) for the MAF
I got an Airaid air intake tube. I kept the stock air box as it is actually already an excellent very well design that pulls air from the fender while most all aftermarket cold air intakes pull air from the exact same place and many from also under the hood. I also have an Airaid performance air filter which flows a good bit better than the stock filter.
If any check engine lights or codes - you need to find out what they are and address those issues.
Remove and carefully clean the throttle body.
Cleaning the inside of the intake manifold is a pretty involved procedure and I'd not recommend that unless you really want to as it requires new gaskets and a lot of work. I only did because I needed to replace the knock sensors which require pulling the intake anyways.
Get a handheld tuner. My personal choice for the do it your-selfer would be a Diablosport Intune. That has a few very good stock tunes and when you are ready you can lookup Lewis (google diablosport lewis custom tune) and pay him to do a custom tune up. That will really wake things up as well as dramatically improve shifting.
Next bigger step is the exhaust. I went with the somewhat lower cost brand OBX from an eBay seller. Its the full stainless long tube set with the high flow cats. Then I lucked out and found a new old stock GM Performance (its made by Borla and is their touring kit) parts stainless cat-back exhaust kit. Both kits together replace the entire exhaust system end to end. When I did the exhaust I also spend a bit extra and went ahead and replaced both of the upstream O2 sensors.
All of the above - I've probably spent $1500 or so doing but I saved a good bit on that GM Performance Parts exhaust bit.
I do have the Diablosport Intune and am running the performance tune. Keep in mind, with a premium performance tune or if you get a supercharger you will need to always run premium fuel. You can get severe spark knock if you run regular gas which can cause major engine damage. If you do not want to run premium a supercharger will be out but you can still run a performance tune, just needs to be one that has the timing cut back a little so you do not get any knocking. A good custom tune also modifies the transmission shifting significantly as well.
I figure with everything I've done above and running the premium performance tune that I've probably picked up around 60 to 75 HP overall. Of course the basic tuneup does not add any horsepower per say, that just helps restore the original power that has declined from the old components. The biggest gains came from the free flowing exhaust system, better flowing air intake, and the custom tune. The air intake by itself will realistically only gain you maybe 3 to 10 HP depending on what all you get. The header kit really needs everything after the cats as well to fully realize the gains from that which are probably around 25 HP for the header kit by itself and closer to 35 HP if you replace it all end to end like I did. The major improvements in airflow both coming in and going out combined with (as well as running as good as it can from the tuneup) a custom tune are big improvements.
#16
11-06-2017, 07:04 AM
Talk about getting ome's attention. I have done it all but the supercharger. And yes, that's next. So you have done it already and how did it go, or can you point me to your post?
MixMansc, hey bro, I see this is an old topic. Did you do it too.
You boys got me going this morning. I pulled and replaced the entire engine (a Christmas gift for my baby) last year and did all the other parts but now it's almost Christmas again. She was born in 2006 and no doubt deserves a supercharger for Christmas this year.
The engine was easy to convince my wife to do and all the tuning and exhaust of course was needed with it. This may be a bit trickier😀. It's not that she would not let me do it. She just believes if I spend money on something she needs to also. Everything costs me double. It's like living in a shoe store. Her closet is so big you could hold a dance in it.😀
Ted
MixMansc, hey bro, I see this is an old topic. Did you do it too.
You boys got me going this morning. I pulled and replaced the entire engine (a Christmas gift for my baby) last year and did all the other parts but now it's almost Christmas again. She was born in 2006 and no doubt deserves a supercharger for Christmas this year.
The engine was easy to convince my wife to do and all the tuning and exhaust of course was needed with it. This may be a bit trickier😀. It's not that she would not let me do it. She just believes if I spend money on something she needs to also. Everything costs me double. It's like living in a shoe store. Her closet is so big you could hold a dance in it.😀
Ted
#17
11-06-2017, 08:31 AM
From a GM Parts Service bulletin.... (it includes 2003-2007 Hummer H2 as well as most every other GM with a V8 engine from 1999-2007)
PARTS INFORMATION: A New Spark Plug has been released for use in the above vehicles. The New Spark Plug has an Iridium tip instead of the current Platinum tip. Due to the different tip design, the gap of the spark plug has also changed. The New Spark Plug, A/C Delco Iridium Part Number 41-110, is Gapped to 1.01mm (0.040 inches) when the Spark Plug is made. The Spark Plug Gap is set during Manufacturing and should Not be Changed to the Gap required with the Platinum plug, or Damage to the Spark Plug may result."
Hi Ted - no this is current topic but no a supercharger not something I've done yet. I really want to though but finding the time and of course the wife factor will come into play.
I was thinking this might be a good approach. 
#18
11-07-2017, 03:08 AM
I too have gone down a similar path-
https://www.hummerforums.com/forum/h...catback-36194/
Basically Long tube headers, borla catback, fast cats, blackbear performance, airdoc (similar variant to airraid) and a free flowing filter. Definitely keep the air box sealed.
I went with a mail order tune (after several iterations) as I am based in Russia, but i would have paid for the tuner to sit in the car and do a personal one if i was closer. Justin at blackbear performance if you ever fancy a trip to Moscow, i'll house and feed you!
Night and day difference.
https://www.hummerforums.com/forum/h...catback-36194/
Basically Long tube headers, borla catback, fast cats, blackbear performance, airdoc (similar variant to airraid) and a free flowing filter. Definitely keep the air box sealed.
I went with a mail order tune (after several iterations) as I am based in Russia, but i would have paid for the tuner to sit in the car and do a personal one if i was closer. Justin at blackbear performance if you ever fancy a trip to Moscow, i'll house and feed you!
Night and day difference.
#19
11-07-2017, 09:50 PM
If you want to stay with your current motor a lot can be done.
Cams, intake, headers, custom tune, etc.
I'd start with the basics.
New spark plugs ( I like to go a range colder on the plugs)
New plug wires depending on how old yours are.
New primary O2 sensors.
Now if you really want to go into the rabbit hole, you can get a turbocharged diesel duramax engine and Allison transmission shoe horned into your H2
Cams, intake, headers, custom tune, etc.
I'd start with the basics.
New spark plugs ( I like to go a range colder on the plugs)
New plug wires depending on how old yours are.
New primary O2 sensors.
Now if you really want to go into the rabbit hole, you can get a turbocharged diesel duramax engine and Allison transmission shoe horned into your H2
#20
11-07-2017, 10:14 PM
If you want to stay with your current motor a lot can be done.
Cams, intake, headers, custom tune, etc.
I'd start with the basics.
New spark plugs ( I like to go a range colder on the plugs)
New plug wires depending on how old yours are.
New primary O2 sensors.
Now if you really want to go into the rabbit hole, you can get a turbocharged diesel duramax engine and Allison transmission shoe horned into your H2
Cams, intake, headers, custom tune, etc.
I'd start with the basics.
New spark plugs ( I like to go a range colder on the plugs)
New plug wires depending on how old yours are.
New primary O2 sensors.
Now if you really want to go into the rabbit hole, you can get a turbocharged diesel duramax engine and Allison transmission shoe horned into your H2
. for now starting with the basics & im gunna have fun doing it