DOD / AFM delete parts

[tooleyondeck]

trouble is, that is a 3-bolt cam. and if i want to preserve the VVT, i need a 1 bolt cam.

I think your problem there will be finding a VVT tuner depending on where you live. If it were me, and it possibly will be in the future, I would get a cam that retains your factory TC (Truck Norris, Chopababra, etc.) and a DOD/VVT Delete Kit from TSP/BTR/GPI etc., get a tune, and call it a day.

 

[Marky Dissod]

Exactly how old was this old bubba?
At what RpM did it upshift @ WOT?
And did you get it tuned after installing 4.11?
Without a thorough tune, I can understand why it did not live up to expectations.

2001 Suburban. Im not sure about the WOT upshift, as i dont often go to full throttle.
And I only did a tune in the DIY sense with a small Accel Supertuner handheld. I used it to change the gear ratio setting, the tire size setting, and install what they call the '87 octane' tune.

You got a canned tuna. Kinda like walking up to a vending machine to order a burger - you don't get to choose which fixins you get or don't get, or how much or how little ...
Even a mail order tune would suit you - or anyone else - far more idiosyncratically.
So as not to bore you with the full explanation; bet you'd appreciate a transmission that did not upshift so early and would downshift with a wee less prodding.
You'd like 4.11 a whole lot more, I guarantee, even if you're not a leadfoot like me.
Even before Engine Half@$$, one of the hidden benefits of a thorough tune, your transmission will last longer.

 

[JKaechler]

Am I understanding correctly that the VVT has its impact up in the high rev ranges, and its absence would not really affect my general usage? mostly driving in the 1200-2500 RPM range, and getting higher mostly when getting on the freeway..... or the occasions when i stomp on the gas because its fun

I would get a cam that retains your factory TC (Truck Norris, Chopababra, etc.

I think I missed an acronym here... TC? Torque Convertor? If so, thats already been replaced recently with a billet one that is supposed to be the same performance as stock, but tougher. my transmission guy told me that the factory one was done for (not a surprise) and recommended the beefier replacement.



I think you guys have convinced me about proper tuning. Is there a way to do it right myself? HP TUner? Being an IT guy by trade i am certainly not afraid of some programming. Are there any shops in Central Texas who can do it? and what kind of budget for tuning do i need to plan for?

 

[Foggy]

The VVT Tuning is no big deal... If your VVT cam is "bigger" then yes, you
will need to install a limiter at time of install - not a big deal..
And VVT is most active in the mid rpm range from the factory...
It reduces reversion in the intake manifold and gives better MPG...
Not really a performance type of device, it's a MPG device.
But either way, the tuning part of it is just 1 table in HPTuners

 

[Marky Dissod]

Am I understanding correctly that the VVT has its impact up in the high rev ranges?
and its absence would not really affect my general usage?

No. GM LS VVT makes MORE low-RpM torque by retarding the camat lower RpMs & smaller throttle openings.

The "parked" or standard position for VVT engines is full advance.
Beyond a certain RpM, over a certain TPS%, VVT basically relaxes as RpMs climb.
In other words, the way normal people drive, it is usually in effect, improving MpGs & low-RpM torque.

 

[Foggy]

No. GM LS VVT makes MORE low-RpM torque by retarding the camat lower RpMs & smaller throttle openings.

The "parked" or standard position for VVT engines is full advance.
Beyond a certain RpM, over a certain TPS%, VVT basically relaxes as RpMs climb.
In other words, the way normal people drive, it is usually in effect, improving MpGs & low-RpM torque.

I repectfully disagree.. and maybe there's something I don't know... But the VVT tables
from GM are set up ONLY to retard cam timing... Not able to advance.
That's why they use a tiny cam and then add it some cam retard up at the
top rpm to make it "act" like a larger cam...

Retarding a cam at LOW Rpm would make it "act" like a much larger cam ---
Exactly what you Don't want in low rpm/torque demand situations.
It retards the cam timing in the low/mid rpms to reduce intake manifold vacuum
and therefore less reversion increasing MPG and light throttle cruising speeds.
And then a little cam retard up near the top rpm to get the little cam to "act" like
a bigger one for the high rpm power increase..
It's like getting a small cam and medium cam all in one !!!!

 

[Foggy]

To add: when you install a larger than stock VVT cam (especially with higher lift)
you have to install a cam limiter so the VVT can't change the cam timing more
than 20*, otherwise you'll kiss the valves to the pistons since these engines
have a pretty tight PTV clearance anyway... Lot diff than the old small blocks chevys
I built (and continue to) for many years.
But it a "non adjustable cam timing" set up, you can either choose the
big cam for high end power or the little one for low end and better driveability.
That's why these modern engines can idle at 550 rpm and pull all the way
up to 6500 Rpm smoothly with a great tq/hp curve.
I chose to stay with VVT and go as small as possible to keep my low end
TQ for towing with a 6K Lb Truck.
If it was a camaro/vette/ hot rod, I'd ditch the VVT and just go with a bigger/more
aggressive cam

 

[Marky Dissod]

https://www.motortrend.com/how-to/advantages-using-vvt-cam-gen-iv-gen-v-engine/

Read it.

 

[Foggy]

Even then, this greater movement is limited to light throttle applications where the cam is retarded to reduce manifold vacuum. By minimizing intake manifold vacuum, less negative work is done, which offers a slight benefit to fuel mileage.

The "parked" or standard position for VVT engines is full advance. So when viewing the VVT table on a HP Tuners or EFILive edit screen, you will see a chart with mostly doubledigit numbers. These numbers represent the amount of retard tuned into the system.

This is pasted from the article linked... (its gen V, but gen IV is similar)
EXACTLY what I said earlier... I don't see the argument Marky Dissod
??????????

 

[Foggy]

https://www.motortrend.com/how-to/advantages-using-vvt-cam-gen-iv-gen-v-engine/

Read it.

Even then, this greater movement is limited to light throttle applications where the cam is retarded to reduce manifold vacuum. By minimizing intake manifold vacuum, less negative work is done, which offers a slight benefit to fuel mileage.

The "parked" or standard position for VVT engines is full advance. So when viewing the VVT table on a HP Tuners or EFILive edit screen, you will see a chart with mostly doubledigit numbers. These numbers represent the amount of retard tuned into the system.

Exactly what I said earlier... I don't see where you think VVT can ADVANCE the cam timing