Input or advice from others on cam swap for 6.2L 2011 Yukon Denali

[j91z28d1]

are these converters different than the old school ones?

cams used to "push" thru a converter before because the tuner had to increase the idle rpm to get the thing to run with a cam. the stock cam wouldn't let it slip enough to get to the extra rpm. so it needed the looser converter to allow for the higher idle rpm.

more power at the same rpm makes a converter slip more, not less. like you used to put a v6 converter behind a v8 and the extra tq made it act like a looser converter.

 

[JPS0284]

The cam picks up torque in those ranges, then pulls strong all the way to 6 grand, I set the over rev at around 6200 because of the intake manifold. If you have long tubes it will help up top to rev it out higher as well. The bottom end is safe to over 7 grand, and the valvetrain is good to around 6800 with the heavier l92 intake valves, so you just rev as high as you can until it stops making power, you will feel it fall off if street tuning, or see it on dyno.
Tuning is for sure not for a newbie, your 6 speed is tuned via torque. It used to be easy to tune the 4l80e and 4l60/70e stuff for newbies with a few simple blanket changes, but you can kill a 6 speed super duper quick once you change the actual delivered torque of the engine vs the conceived engine torque the transmission thinks is going on.
I don't do mail order tunes, but people seem happy with the black bear guy on here, or find a good local tuner. Make sure you resist the urge to go out and drive it without a base tune after its done. You can smoke the 6 speeds easier at part throttle if something is off , than at full throttle. It will at the very least, hit its max stock line pressure settings at full throttle after modded with no tune, but it will be capable of making much more torque at lower perceived delivered torque numbers,...then it overpowers the clutches.

I definitely can’t afford to grenade anything after dumping that much into it, how much does a tune normally run?

 

[hagar]

I was thinking about skipping all their provided gaskets and getting oem replacements on rockauto. So don’t go with the Delphi lS7 lifters? I was hoping there was going to be room in the budget for some 1 7/8 long tube headers n Y pipe this is getting pricey

I have ran probably 100 sets of ls7 lifters, they were always the go to lifters as far back as 2006 when they came out. The problem is that there is something seriously wrong with over seas lifters for the last few years, and currently. Even with oem gm and dodge and Ford, their number one issue with brand new vehicles has been lifters. A guy could almost make a conspiracy theory about the problem.
It makes me cringe every single time I order a set of the Johnsons, I constantly find myself trying to talk myself into going with a lesser version. Look on all big hitter websites and it says it all. They simply won't warranty anything but Johnson lifters. Order a tsp long block, and they won't warranty it unless you buy the Johnson lifters. They have many other lines they sell, that I guarantee they make much more money off than selling the Johnsons. Like 100000 million percent guarantee it. I wouldn't be surprised if they are working on making their own line right now, they openly admit it is a problem.
I currently put lifters as the most important thing to suck it up on. It's too much work and potential damage to save 400 bucks.

 

[hagar]

are these converters different than the old school ones?

cams used to "push" thru a converter before because the tuner had to increase the idle rpm to get the thing to run with a cam. the stock cam wouldn't let it slip enough to get to the extra rpm. so it needed the looser converter to allow for the higher idle rpm.

more power at the same rpm makes a converter slip more, not less. like you used to put a v6 converter behind a v8 and the extra tq made it act like a looser converter.

That is 100 percent true. You don't idle at the stock 575 rpm when hot with a cam. Raising the rpms to where the aftermarket cam want to be at to idle proper, combined with running stock or normally reduced amount of idle timing, creat a push against the converter. The idea is to reduce timing while the engine rpm is higher. A 6l80, especially with its first gear ratio and a big 6.2 liter engine, start to make some decent takeoff power at 750 to 800 rpm. The way I fight it is to pull timing to kill the power.

 

[hagar]

I definitely can’t afford to grenade anything after dumping that much into it, how much does a tune normally run?

Depends where you are. I am way up in Canada, no way I can do it for ya. Where you at? So many good tuners all over the states these days. It's a basic tune.

 

[j91z28d1]

I did just see.a thing about ls7 lifters and ls7 style lifers being 2 different things. like 2 different part numbera, but the cheap ones are being sold as ls7s by throwing style in there.

makes me wonder if the true oem ls7 lifters are discounted at this point, and all we are left with are the lower level ones.

 

[hagar]

I did just see.a thing about ls7 lifters and ls7 style lifers being 2 different things. like 2 different part numbera, but the cheap ones are being sold as ls7s by throwing style in there.

makes me wonder if the true oem ls7 lifters are discounted at this point, and all we are left with are the lower level ones.

I get it from the mouth of people who know and won't warranty. Been a tsp dealer for something like 16 years, whenever they started many moons ago, they talk to me proper. They won't warranty the Delphi ones either.

 

[hagar]

I get it from the mouth of people who know and won't warranty. Been a tsp dealer for something like 16 years, whenever they started many moons ago, they talk to me proper. They won't warranty the Delphi ones either.

I placed an order this week with them and my normal sales guy said something about comp having a lifter that gets warranty now, but it sounded like a new thing, and comp is classic for failure on things valvetrain that the cam spins, so I wouldn't suggest it personally.

 

[JPS0284]

I have ran probably 100 sets of ls7 lifters, they were always the go to lifters as far back as 2006 when they came out. The problem is that there is something seriously wrong with over seas lifters for the last few years, and currently. Even with oem gm and dodge and Ford, their number one issue with brand new vehicles has been lifters. A guy could almost make a conspiracy theory about the problem.
It makes me cringe every single time I order a set of the Johnsons, I constantly find myself trying to talk myself into going with a lesser version. Look on all big hitter websites and it says it all. They simply won't warranty anything but Johnson lifters. Order a tsp long block, and they won't warranty it unless you buy the Johnson lifters. They have many other lines they sell, that I guarantee they make much more money off than selling the Johnsons. Like 100000 million percent guarantee it. I wouldn't be surprised if they are working on making their own line right now, they openly admit it is a problem.
I currently put lifters as the most important thing to suck it up on. It's too much work and potential damage to save 400 bucks.

Well I’ll take your recommendation and go with the Johnson lifters. I’ll just have to put the project on hold for a few more weeks. I wanted to do long tube headers and a Y pipe at the same time and just make a weekend out of it.

 

[hagar]

Well I’ll take your recommendation and go with the Johnson lifters. I’ll just have to put the project on hold for a few more weeks. I wanted to do long tube headers and a Y pipe at the same time and just make a weekend out of it.

It sucks, but we don't have anyone backing us if something goes wrong. It's full labor, full new gaskets, and if a lifter fails, usually new cam at best. They can spin and wreck the block. It stood out to me that you said how towed and went places, so that is also a factor. I would be more open to some weekend warrior that treated his vehicle like a toy, but yours is not that. Just look at the 400 dollars you are saving by buying the tsp long tubes and y pipe as a wash on the extra lifter price. Vehicles require positive energy, or it isn't fun.

 

[JPS0284]

Depends where you are. I am way up in Canada, no way I can do it for ya. Where you at? So many good tuners all over the states these days. It's a basic tune.

I’m in south west Michigan, I googled it and there isn’t much around here I’ll probably have to email it to black bear or whoever does it remotely. Im assuming if I ordered hp tuners I can download my trucks oem tune and send it to them before I start doing the work then load it once I’m finished?

 

[JPS0284]

It sucks, but we don't have anyone backing us if something goes wrong. It's full labor, full new gaskets, and if a lifter fails, usually new cam at best. They can spin and wreck the block. It stood out to me that you said how towed and went places, so that is also a factor. I would be more open to some weekend warrior that treated his vehicle like a toy, but yours is not that. Just look at the 400 dollars you are saving by buying the tsp long tubes and y pipe as a wash on the extra lifter price. Vehicles require positive energy, or it isn't fun.

That’s very true, I’m a mechanical contractor (hvac) so I often have this same conversation with clients I completely understand where your coming from and appreciate the advice.

 

[hagar]

I’m in south west Michigan, I googled it and there isn’t much around here I’ll probably have to email it to black bear or whoever does it remotely. Im assuming if I ordered hp tuners I can download my trucks oem tune and send it to them before I start doing the work then load it once I’m finished?

Yep! I think he has a thing he sends that does something more simple than buying your own hp tuners cable though.

 

[hagar]

That’s very true, I’m a mechanical contractor (hvac) so I often have this same conversation with clients I completely understand where your coming from and appreciate the advice.

Lmao!! Being and HVAC guy in Michigan of all places, I am positive you get it!

 

[hagar]

Lmao!! Being and HVAC guy in Michigan of all places, I am positive you get it!

BTW, my number one trade of customers is HVAC guys, there must be some sort of correlation there if a guy thought hard enough about it.

 

[91RS]

I have done a few more since, still love them. I have never in my life had a spring fail on any of the supplied tsp PAC springs. I use them on cars pushing over 7 thousand rpms as well. I have personally installed traditional delete cams in 6.2s, and stand solidly by my statement that the vvt Cams are super awesome for the heavy trucks.

Agreed. I'm still very happy with my Comp VVT cam. I'd almost love to change it to the TSP cam since theirs should make more power but I don't feel like taking it apart to do it and pay for a retune.

 

[Geotrash]

This thread is a great resource that I wish I'd had when I did mine a couple of years ago. I'm still happy with the setup I landed on though. Cam Motion Stage 2 truck cam (3-bolt), Chevrolet Performance LS7 lifters with BTR beehive springs and moly pushrods. Just finished a 2500 mile camping trip through the northeast pulling our 7500 lb camper, and never ran short on power anywhere. On a few long grades when I had to downshift to 3rd, I had to keep my foot out of it or it'd keep accelerating.

Side note: I have never been able to find a chart or performance data for VVT vs non-VVT at lower RPMs where it's supposed to be most effective, so I'm still skeptical of its benefits outside of fuel mileage. I also have a 2007 XL Denali that still has the stock cam and VVT and the 2012 with the 3-bolt cam will outrun it off the line pulling the same camper, all the way through the rev range. On the same highway entrance ramp near my house, I'm 10 mph faster merging onto the highway with the 2012 than I am with the 2007 when towing. The only significant difference is the cam. And both are Black Bear tuned for premium fuel.

 

[j91z28d1]

I'm pretty sure I've seen a dyno graph somewhere, but I'm not sure where. maybe Texas speed site?

that Richard Holden guy on YouTube did a video on advancing and retarding a cam in a 5.3 I believe it was. mechanically with the adjustable bushings and if I remember right he couldn't get anything out of it. I don't 100% agree with his videos. he seems to have an agenda going into it and then pulls up saved dyno runs from years past to prove it. it feel like it lacks 100% objectivity. like if he's showing you something he wants to look good he'll show you results from it on a 427ci full out race build. if he wants to show it doesn't work, he'll show those parts on a stock 5.3.

so yeah, no clue what to believe. it sounds good in theory but not sure it works enough for the hassle it causes.

 

[hagar]

I'm pretty sure I've seen a dyno graph somewhere, but I'm not sure where. maybe Texas speed site?

that Richard Holden guy on YouTube did a video on advancing and retarding a cam in a 5.3 I believe it was. mechanically with the adjustable bushings and if I remember right he couldn't get anything out of it. I don't 100% agree with his videos. he seems to have an agenda going into it and then pulls up saved dyno runs from years past to prove it. it feel like it lacks 100% objectivity. like if he's showing you something he wants to look good he'll show you results from it on a 427ci full out race build. if he wants to show it doesn't work, he'll show those parts on a stock 5.3.

so yeah, no clue what to believe. it sounds good in theory but not sure it works enough for the hassle it causes.

There is a reason you don't put a non vvt cam into a vvt controlled system. If it was as simple as advancing and retarding a normal cam, it would be one thing, but there are many many hours spent on development of the l92 vvt cams to take advantage of the technology.

 

[Geotrash]

There is a reason you don't put a non vvt cam into a vvt controlled system. If it was as simple as advancing and retarding a normal cam, it would be one thing, but there are many many hours spent on development of the l92 vvt cams to take advantage of the technology.

I hear you, but that’s exactly what I did, and it’s working great for me. I’m not trying to debate anyone here. I’m just saying that I have never seen any evidence of what the actual power gains are for VVT at lower RPMs. I hear lots of hand waving and wows, but there seems to be two sides to this issue, and no clear resolution with data.

I searched for a few weeks when I was making my decisions a few years ago and came up short.