Building motor for my tow rig. Need HELP!!!
05-10-2020, 02:58 PM
#21
thanks for the comment
05-10-2020, 03:55 PM
#22
Long tube headers and a tune would be the main 2 things you could do to increase low speed torque. Unless you just wanna throw 5,000-8,000 dollars into a $3,000 - 4,000 truck to gain 60ftlbs of torque with a stroker kit.... just doesn’t seem very logical. Boost would be cheaper and give you far better results like mentioned earlier.
i need to take the truck to the gym a few days a week Gains not yoga class Gains.
Second, it is more about reliable power Across the rpm range than just getting it done so skipping the internals makes no sense. I have seen Tuners go too far on stock internals and handed great numbers over but a hand grenade of an engine as well.
Yes this is a budget build in that I’m only going to spend so much but it does not mean doing things recklessly. I don’t know about you and everyone else on the forum but the wear surfaces, piston bores, and all other critical dimensions will be checked and machined to ensure I know where I’m starting and not just hoping I got a good one. Because of this throwing in a stroker kit would not be additional inconvenience. Plus I won’t have to worry about rebalancing like I would with just forged pistons and rods.
Last point, I don’t know where you are getting dollar figures. Long tube headers and a tune will be at least $1000 plus the rest of the exhaust work. If I did a cam and springs I’m at $1000 but will net much better gains. Plus $1000 for the pistons, rings, bearing kit, gasket set. Less than $1000 for the machine work and all other hardware and upgrade parts. I will be right around $3k in the motor that has the potential to handle big power if I ever decided to go that route And is essentially a new motor.
side note: I don’t plan on getting rid of the original motor. If I ever go to sell the truck I would take the “build” motor out, put stock back in, and save the good motor for the next project.
05-10-2020, 04:49 PM
#23
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Originally Posted by COwens36
now we are talking lol. Do they make a root style blower I can stick out the hood for this motor lol.
i wouldnt want to add FI without better internals but I like where your head is at. Unfortunately, building the motor for boost puts it out of my price range.
i wouldnt want to add FI without better internals but I like where your head is at. Unfortunately, building the motor for boost puts it out of my price range.
05-10-2020, 04:59 PM
#24
I'm pretty sure leaving the exhaust stock and slapping a stroker in is two steps forward one step back.
I have a 2001 GMC Yukon Denali with a 6.0l and a 4l80e transmission and full tow package. I would lay out for certain what gear and transmission your truck has before any suggestions can be taken.
I have a 2001 GMC Yukon Denali with a 6.0l and a 4l80e transmission and full tow package. I would lay out for certain what gear and transmission your truck has before any suggestions can be taken.
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00pooterSS (05-11-2020)
05-10-2020, 05:10 PM
#25
I'm pretty sure leaving the exhaust stock and slapping a stroker in is two steps forward one step back.
I have a 2001 GMC Yukon Denali with a 6.0l and a 4l80e transmission and full tow package. I would lay out for certain what gear and transmission your truck has before any suggestions can be taken.
I have a 2001 GMC Yukon Denali with a 6.0l and a 4l80e transmission and full tow package. I would lay out for certain what gear and transmission your truck has before any suggestions can be taken.
Just so everyone understands I’m not stupid. If I am pulling more air in the cylinder it will have to push more out thus a stroker kit would need an exhaust. The gentlemen was expressing that just a set of headers and a tune would be sufficient for what I needed. If I just swap to the flat top pistons then it would pull in 6.7cc less air but compress it much further and on the exhaust stroke it would have a higher pressure and will push out more of the exhaust so exhaust shouldn’t be needed especially if the valve is open longer with a cam. Don’t get me wrong adding the exhaust will benefit but the amount vs the cost doesn’t make it super important unless I stroke the truck.
i will go check the RPO and see what it says.
05-10-2020, 05:14 PM
#26
is your truck the XL? That is interesting about the 4l80e. I’m 99% sure mine is the 65 but I will go verify by the rpo code.
Just so everyone understands I’m not stupid. If I am pulling more air in the cylinder it will have to push more out thus a stroker kit would need an exhaust. The gentlemen was expressing that just a set of headers and a tune would be sufficient for what I needed. If I just swap to the flat top pistons then it would pull in 6.7cc less air but compress it much further and on the exhaust stroke it would have a higher pressure and will push out more of the exhaust so exhaust shouldn’t be needed especially if the valve is open longer with a cam. Don’t get me wrong adding the exhaust will benefit but the amount vs the cost doesn’t make it super important unless I stroke the truck.
i will go check the RPO and see what it says.
Just so everyone understands I’m not stupid. If I am pulling more air in the cylinder it will have to push more out thus a stroker kit would need an exhaust. The gentlemen was expressing that just a set of headers and a tune would be sufficient for what I needed. If I just swap to the flat top pistons then it would pull in 6.7cc less air but compress it much further and on the exhaust stroke it would have a higher pressure and will push out more of the exhaust so exhaust shouldn’t be needed especially if the valve is open longer with a cam. Don’t get me wrong adding the exhaust will benefit but the amount vs the cost doesn’t make it super important unless I stroke the truck.
i will go check the RPO and see what it says.
05-10-2020, 05:39 PM
#27
BIG gains, and budget are never going to work well together... you will be over 3k just on the bottom end. Another 2-3k+ to finish it right (with stock heads and intake). Then you better hope your machine shop knows what there doing or you will have a very expensive time bomb on your hands....
The BIG gains on a budget will come from a LSA or turbo, but you better keep a spare trans on the shelf lol
05-10-2020, 06:03 PM
#30
Completely false, long tube headers will give gains across the entire RPM range and will actually gain more down low than up high in the rev range
BIG gains, and budget are never going to work well together... you will be over 3k just on the bottom end. Another 2-3k+ to finish it right (with stock heads and intake). Then you better hope your machine shop knows what there doing or you will have a very expensive time bomb on your hands....
The BIG gains on a budget will come from a LSA or turbo, but you better keep a spare trans on the shelf lol
BIG gains, and budget are never going to work well together... you will be over 3k just on the bottom end. Another 2-3k+ to finish it right (with stock heads and intake). Then you better hope your machine shop knows what there doing or you will have a very expensive time bomb on your hands....
The BIG gains on a budget will come from a LSA or turbo, but you better keep a spare trans on the shelf lol
05-10-2020, 06:50 PM
#33
https://www.fourwheeler.com/how-to/e...-long-headers/
https://www.streetmusclemag.com/tech...-hemi-headers/
https://www.hotrod.com/uploads/sites...ound%7C875:492
05-10-2020, 07:09 PM
#34
Im pretty sure it is I'll try and get a pic of it tomorrow. I'll have to also snag an pic of the RPO to make sure it is what it is.
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Ls7colorado (05-10-2020)
05-11-2020, 06:33 AM
#37
05-11-2020, 06:41 AM
#38
in 01 GMC made the Yukon xl 2500. It came with the LQ4, 4l80e, 3/4 ton suspension and 4.10 gears. The Denali package was more appearance and luxury than anything. Kind of like the Chevy burban 2500 with the 8.1l big block. Straight up unicorns but they exist.
05-11-2020, 09:59 AM
#39
You mentioned low end torque... can you be more specific what your issue is when towing? Is it getting started, or is it being able to hold a speed going uphill?
What speed, gear, rpm are you turning now, and where do you want it to be?
You have a lot working against you, and some of your plans seem counter to what most would consider common sense, which is why you are getting a lot of varied response.
First, you are towing 8900 lbs... which is over the tow rating of the vehicle (8200lbs is the 2002 Yukon D rating). And in the mountains. And we are talking a truck from ~2000 (design wise, even if its a few years newer). I was towing a lot of car haulers (offroading pulling tall Jeeps with a lot of wind resistance) with friends thru the 90s-2010s. So I got to see a lot different combos. I'll say the people with LQ4s back then weren't terribly impressed in stock form with the trucks. In my opinion, there were big jumps in towing capability from the beginning of the 2000s to the end. I know my 2009 F150 5.4 6 speed auto easily out-towed my 2000 Ram 2500 (5.9). On several trips, with similar loads (7000lb trailers), my 6 speed F150 did a better job vs two friends with LQ4s in mid 2000s Chevys. They tended to need 3rd gear, where I could stay in OD. I would guess you need to be in 3rd or even 2nd gear depending on the grade.
This is also one of the issues with the 4L65e, there is a 30% drop between 3rd and 4th, which frustrates people towing. The 4L80e is only a 25% drop, for example. That *is* a lot of trailer for a 4L65e, and adding more power in front isn't a recipe for it to last. (I run a 4L65e behind a built LQ4 btw but I wouldn't want to tow like that with one).
If you are looking for more power off the line, don't overlook an improved towing torque converter with a higher STR. We used to use Hughes Tow-Master line in our off road Jeeps for the same benefit, a little more low end, without too much heat generation. I would definitely want a big cooler, no matter what.
Overall, the best thing you can do for towing is more cubes. I'd look for a budget stroker setup, that will help all over. You *will* need to do some retuning in any case to gain the full benefit of anything you do.
IMO, I would not spend extra money on any forged parts, just to have them. Not necessary for what you want to do.
If you are staying with a stock size engine, you are likely at your best cost/performance point to buy a decent used short block. These engines seem to be most reliable when left alone, and under 200k isn't much for them. So finding a lower miles bottom end, especially if you can get an 2004+ with the gen IV stronger rods is a good value.
If it was me, I'd look at one of these scenarios, in order of preference:
1) Bite the bullet, save, and get a better matched tow vehicle.
if not that:
2) Plan a budget conscious 408 Stroker. Cubes will make more torque throughout the range.
if not that:
3) Find a reasonable mileage short block or long block 6.0. To gain power throughout the range, I would do the following:
- Bump compression a little, like 10:1 or so, so if you can find an LQ9 bottom end, or 243/799 heads
- Have the heads CNCd, or at least good valve job. Good flowing heads with small port volume is usually a good thing across the powerband
- Long tube headers, good exhaust
- A Trailblazer SS intake manifold tends to make power everywhere, if you find one cheap as a complete takeoff. But you need to figure out your fuel rail/injector situation. I run this intake on my LQ4, and I can feel the difference compared to the early truck intake that I ran.
- Consider a better torque converter and transmission cooling.
- Consider 4.10 gears. They are available out there I believe as OEM and aftermarket, just have them installed, or learn how to do it yourself. Isn't it just a standard GM 8.25 front diff? Silverado SS AWD trucks came with 4.10s.
If you increase the cam, and it probably makes sense to investigate a tiny towing cam, gears and/or converter should always be considered at the same time.
I wouldn't spend time or money on any bottom end parts or machine work, unless it was a stroker. That would have been much more common on an older SBC or other older platform. These engines usually are just fine and most reliable when left alone.
What speed, gear, rpm are you turning now, and where do you want it to be?
You have a lot working against you, and some of your plans seem counter to what most would consider common sense, which is why you are getting a lot of varied response.
First, you are towing 8900 lbs... which is over the tow rating of the vehicle (8200lbs is the 2002 Yukon D rating). And in the mountains. And we are talking a truck from ~2000 (design wise, even if its a few years newer). I was towing a lot of car haulers (offroading pulling tall Jeeps with a lot of wind resistance) with friends thru the 90s-2010s. So I got to see a lot different combos. I'll say the people with LQ4s back then weren't terribly impressed in stock form with the trucks. In my opinion, there were big jumps in towing capability from the beginning of the 2000s to the end. I know my 2009 F150 5.4 6 speed auto easily out-towed my 2000 Ram 2500 (5.9). On several trips, with similar loads (7000lb trailers), my 6 speed F150 did a better job vs two friends with LQ4s in mid 2000s Chevys. They tended to need 3rd gear, where I could stay in OD. I would guess you need to be in 3rd or even 2nd gear depending on the grade.
This is also one of the issues with the 4L65e, there is a 30% drop between 3rd and 4th, which frustrates people towing. The 4L80e is only a 25% drop, for example. That *is* a lot of trailer for a 4L65e, and adding more power in front isn't a recipe for it to last. (I run a 4L65e behind a built LQ4 btw but I wouldn't want to tow like that with one).
If you are looking for more power off the line, don't overlook an improved towing torque converter with a higher STR. We used to use Hughes Tow-Master line in our off road Jeeps for the same benefit, a little more low end, without too much heat generation. I would definitely want a big cooler, no matter what.
Overall, the best thing you can do for towing is more cubes. I'd look for a budget stroker setup, that will help all over. You *will* need to do some retuning in any case to gain the full benefit of anything you do.
IMO, I would not spend extra money on any forged parts, just to have them. Not necessary for what you want to do.
If you are staying with a stock size engine, you are likely at your best cost/performance point to buy a decent used short block. These engines seem to be most reliable when left alone, and under 200k isn't much for them. So finding a lower miles bottom end, especially if you can get an 2004+ with the gen IV stronger rods is a good value.
If it was me, I'd look at one of these scenarios, in order of preference:
1) Bite the bullet, save, and get a better matched tow vehicle.
if not that:
2) Plan a budget conscious 408 Stroker. Cubes will make more torque throughout the range.
if not that:
3) Find a reasonable mileage short block or long block 6.0. To gain power throughout the range, I would do the following:
- Bump compression a little, like 10:1 or so, so if you can find an LQ9 bottom end, or 243/799 heads
- Have the heads CNCd, or at least good valve job. Good flowing heads with small port volume is usually a good thing across the powerband
- Long tube headers, good exhaust
- A Trailblazer SS intake manifold tends to make power everywhere, if you find one cheap as a complete takeoff. But you need to figure out your fuel rail/injector situation. I run this intake on my LQ4, and I can feel the difference compared to the early truck intake that I ran.
- Consider a better torque converter and transmission cooling.
- Consider 4.10 gears. They are available out there I believe as OEM and aftermarket, just have them installed, or learn how to do it yourself. Isn't it just a standard GM 8.25 front diff? Silverado SS AWD trucks came with 4.10s.
If you increase the cam, and it probably makes sense to investigate a tiny towing cam, gears and/or converter should always be considered at the same time.
I wouldn't spend time or money on any bottom end parts or machine work, unless it was a stroker. That would have been much more common on an older SBC or other older platform. These engines usually are just fine and most reliable when left alone.
Last edited by Haggar; 05-11-2020 at 10:05 AM.
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Ls7colorado (05-11-2020)
05-11-2020, 05:05 PM
#40
You mentioned low end torque... can you be more specific what your issue is when towing? Is it getting started, or is it being able to hold a speed going uphill?
What speed, gear, rpm are you turning now, and where do you want it to be?
You have a lot working against you, and some of your plans seem counter to what most would consider common sense, which is why you are getting a lot of varied response.
First, you are towing 8900 lbs... which is over the tow rating of the vehicle (8200lbs is the 2002 Yukon D rating). And in the mountains. And we are talking a truck from ~2000 (design wise, even if its a few years newer). I was towing a lot of car haulers (offroading pulling tall Jeeps with a lot of wind resistance) with friends thru the 90s-2010s. So I got to see a lot different combos. I'll say the people with LQ4s back then weren't terribly impressed in stock form with the trucks. In my opinion, there were big jumps in towing capability from the beginning of the 2000s to the end. I know my 2009 F150 5.4 6 speed auto easily out-towed my 2000 Ram 2500 (5.9). On several trips, with similar loads (7000lb trailers), my 6 speed F150 did a better job vs two friends with LQ4s in mid 2000s Chevys. They tended to need 3rd gear, where I could stay in OD. I would guess you need to be in 3rd or even 2nd gear depending on the grade.
This is also one of the issues with the 4L65e, there is a 30% drop between 3rd and 4th, which frustrates people towing. The 4L80e is only a 25% drop, for example. That *is* a lot of trailer for a 4L65e, and adding more power in front isn't a recipe for it to last. (I run a 4L65e behind a built LQ4 btw but I wouldn't want to tow like that with one).
If you are looking for more power off the line, don't overlook an improved towing torque converter with a higher STR. We used to use Hughes Tow-Master line in our off road Jeeps for the same benefit, a little more low end, without too much heat generation. I would definitely want a big cooler, no matter what.
Overall, the best thing you can do for towing is more cubes. I'd look for a budget stroker setup, that will help all over. You *will* need to do some retuning in any case to gain the full benefit of anything you do.
IMO, I would not spend extra money on any forged parts, just to have them. Not necessary for what you want to do.
If you are staying with a stock size engine, you are likely at your best cost/performance point to buy a decent used short block. These engines seem to be most reliable when left alone, and under 200k isn't much for them. So finding a lower miles bottom end, especially if you can get an 2004+ with the gen IV stronger rods is a good value.
If it was me, I'd look at one of these scenarios, in order of preference:
1) Bite the bullet, save, and get a better matched tow vehicle.
if not that:
2) Plan a budget conscious 408 Stroker. Cubes will make more torque throughout the range.
if not that:
3) Find a reasonable mileage short block or long block 6.0. To gain power throughout the range, I would do the following:
- Bump compression a little, like 10:1 or so, so if you can find an LQ9 bottom end, or 243/799 heads
- Have the heads CNCd, or at least good valve job. Good flowing heads with small port volume is usually a good thing across the powerband
- Long tube headers, good exhaust
- A Trailblazer SS intake manifold tends to make power everywhere, if you find one cheap as a complete takeoff. But you need to figure out your fuel rail/injector situation. I run this intake on my LQ4, and I can feel the difference compared to the early truck intake that I ran.
- Consider a better torque converter and transmission cooling.
- Consider 4.10 gears. They are available out there I believe as OEM and aftermarket, just have them installed, or learn how to do it yourself. Isn't it just a standard GM 8.25 front diff? Silverado SS AWD trucks came with 4.10s.
If you increase the cam, and it probably makes sense to investigate a tiny towing cam, gears and/or converter should always be considered at the same time.
I wouldn't spend time or money on any bottom end parts or machine work, unless it was a stroker. That would have been much more common on an older SBC or other older platform. These engines usually are just fine and most reliable when left alone.
What speed, gear, rpm are you turning now, and where do you want it to be?
You have a lot working against you, and some of your plans seem counter to what most would consider common sense, which is why you are getting a lot of varied response.
First, you are towing 8900 lbs... which is over the tow rating of the vehicle (8200lbs is the 2002 Yukon D rating). And in the mountains. And we are talking a truck from ~2000 (design wise, even if its a few years newer). I was towing a lot of car haulers (offroading pulling tall Jeeps with a lot of wind resistance) with friends thru the 90s-2010s. So I got to see a lot different combos. I'll say the people with LQ4s back then weren't terribly impressed in stock form with the trucks. In my opinion, there were big jumps in towing capability from the beginning of the 2000s to the end. I know my 2009 F150 5.4 6 speed auto easily out-towed my 2000 Ram 2500 (5.9). On several trips, with similar loads (7000lb trailers), my 6 speed F150 did a better job vs two friends with LQ4s in mid 2000s Chevys. They tended to need 3rd gear, where I could stay in OD. I would guess you need to be in 3rd or even 2nd gear depending on the grade.
This is also one of the issues with the 4L65e, there is a 30% drop between 3rd and 4th, which frustrates people towing. The 4L80e is only a 25% drop, for example. That *is* a lot of trailer for a 4L65e, and adding more power in front isn't a recipe for it to last. (I run a 4L65e behind a built LQ4 btw but I wouldn't want to tow like that with one).
If you are looking for more power off the line, don't overlook an improved towing torque converter with a higher STR. We used to use Hughes Tow-Master line in our off road Jeeps for the same benefit, a little more low end, without too much heat generation. I would definitely want a big cooler, no matter what.
Overall, the best thing you can do for towing is more cubes. I'd look for a budget stroker setup, that will help all over. You *will* need to do some retuning in any case to gain the full benefit of anything you do.
IMO, I would not spend extra money on any forged parts, just to have them. Not necessary for what you want to do.
If you are staying with a stock size engine, you are likely at your best cost/performance point to buy a decent used short block. These engines seem to be most reliable when left alone, and under 200k isn't much for them. So finding a lower miles bottom end, especially if you can get an 2004+ with the gen IV stronger rods is a good value.
If it was me, I'd look at one of these scenarios, in order of preference:
1) Bite the bullet, save, and get a better matched tow vehicle.
if not that:
2) Plan a budget conscious 408 Stroker. Cubes will make more torque throughout the range.
if not that:
3) Find a reasonable mileage short block or long block 6.0. To gain power throughout the range, I would do the following:
- Bump compression a little, like 10:1 or so, so if you can find an LQ9 bottom end, or 243/799 heads
- Have the heads CNCd, or at least good valve job. Good flowing heads with small port volume is usually a good thing across the powerband
- Long tube headers, good exhaust
- A Trailblazer SS intake manifold tends to make power everywhere, if you find one cheap as a complete takeoff. But you need to figure out your fuel rail/injector situation. I run this intake on my LQ4, and I can feel the difference compared to the early truck intake that I ran.
- Consider a better torque converter and transmission cooling.
- Consider 4.10 gears. They are available out there I believe as OEM and aftermarket, just have them installed, or learn how to do it yourself. Isn't it just a standard GM 8.25 front diff? Silverado SS AWD trucks came with 4.10s.
If you increase the cam, and it probably makes sense to investigate a tiny towing cam, gears and/or converter should always be considered at the same time.
I wouldn't spend time or money on any bottom end parts or machine work, unless it was a stroker. That would have been much more common on an older SBC or other older platform. These engines usually are just fine and most reliable when left alone.
i made another mistake in the information. The trailer fully loaded weighs 6900 not 8900. Don’t know what happened there.
when I pull the mountain the truck struggles to maintain even 55mph in 2nd gear at 5000rpm. I’m looking for torque between 3000 and 6000. If the truck had more torque In that range it would hopefully not struggle so bad pulling the grade or even it might not need to down shift and ring itself out. Only reason I would even think of building it or adding any power to the motor is to pull the mountain better. From a stop the truck pulls just fine even up a hill but it struggles at speed.
I forgot about the ss trucks. I may look into the gearing on those. If everything was available and easy to find then gears would be my first option but I have had a time trying to find gears for the front diff.
I have heard a lot of opinions and information regarding this topic. In the end, it sounds as if I would be waisting money doing anything to the motor in the truck. It also sounds like most are not confident enough in the setup to want to even tow with it. What scares me the most is how widely opinions and experiences vary on here. I’m an old school guy where I know for a fact what an engine could handle, how it would respond to mods, and how to “tune” it myself. I’m beginning to think I don’t even wanna mess with these LS things. I believe I may just go back to a good old BBC and build a monster or go back to the duramax. Either way would be easier than dealing with all this mess.
long story short, I’m just going to either find gears or stick 3/4 ton axle and diff under it. I know this will solve the issue as much as I will hate the side effects.
thanks everyone for their input.