DOD/AFM Delete Valve questions

[Darren2014]

If your heads are not burning oil, I see no reason to lap the valves when doing a DOD delete. Yes, that camshaft was made to work with VVT, so it is backwards compatible. It will work in my older motor without VVT or yours with VVT.

I'd look into using the L9H camshaft is you want to keep VVT working. Note that it is different than the LH9 camshaft, two different motors. I'm in the minority around here, most folks like cams with more than 210 degrees duration for a 5.3 and more lift than the stock springs can handle.

I forget, did your motor fail or is it running fine? If the latter, take your time and don't rush things.

And also isn't the L9H a 6.2? Would that not be an issue putting that cam into a 5.3 motor?

 

[swathdiver]

Also what what benefit does the L9H have over the LH9. I know I’ll loose a little horse power and a little bit of torque with the LH9 but it seems to be the closest thing to a stock cam for my motor minus the DOD. The L9H is impressive with how much more power it would give me, but that worries me since I’m not planning on changing out a ton of parts while I’m in there. I’d prefer to just be able to swap the cam, and lifters, put everything back together and have it tuned. With the L9H I’m worried id need to swap some parts out for others that are beefier than stock.

Well here they are, which is closest to your original while still keeping VVT? Another thing, you'll only gain about 5-7 horsepower by increasing the lift over .500 with stock 243 heads, hardly worth the strain on the valvetrain IMO.

But! I stayed at a Holiday Inn Express last night, let's ask someone who has already done a cam swap in a 5.3 for their input. @iamdub

And also isn't the L9H a 6.2? Would that not be an issue putting that cam into a 5.3 motor?

No, slides right in, same architecture.

 

[iamdub]

I’ll watch some videos and see about doing it. What do you mean a catch cam tho?

Also I’m curious if there’s any precautions I should take while doing the job to insure I don’t get coolant or oil in the wrong areas. Blowing out or vacuuming out certain portions. I’ve seen one video where the guy slipped a slim hose into a port and siphoned out some coolant.

Catch can. It's basically a filter to catch the oil vapors traveling through the PCV system. The oily vapor collects and puddles in the back of the intake manifold and drips into the rearmost combustion chambers. The oil gets burned and cokes up the combustion chambers, sticks piston rings, etc. Pretty much every LS series engine needs a catch can.

It's actually kinda difficult to get coolant where it shouldn't be. Even still, you'd be changing the oil and replacing the coolant after the job so anything that may cross-contaminate will be drained out. The LS engine has a "dry" intake manifold, so there's no coolant mess when you remove it like the older engines. When you pop the heads off, a little coolant will run out of them and into the cylinders. But, it's nothing that can't be soaked up with some shop rags or paper towels. If I'm not pulling the engine, I drain it as much as possible with the lower rad hose removed. Then I jack up the rear of the truck (jack under diff) as high as my jack will go to pour more coolant out through the water pump. Then, with the truck back on the ground, barely any more coolant will run out when I remove the water pump. I use my shop vac over each coolant port to get even more out. After that, it's almost impossible to splash any more coolant out when working on it. I do this with a standard water pump replacement just to minimize the mess. Coolant is very slippery on a shop floor.

Also what are all of the supporting mods you mentioned? I was curious about possibly going the stage 2 route.

LS6 valve springs and a custom tune are the most pertinent and required. But, shaved heads, thinner head gaskets, custom-length push rods, looser stall converter and headers are the extras that aren't totally required but increase power overall, including making up for any lower-end losses the cam may bring. A cam is good and all, but it disrupts a system whose components were all engineered to work together for efficiency and reliability. Changing only the cam yields gains, but the system as a whole is no longer optimal and you end up with sacrifices. The disruption and sacrifices are relatively minimal, especially with "only" a Stage 2, but still less optimal nonetheless.

You have to decide before you tear into it what you ultimately want and are able to do due to time and/or budget and/or service/parts constraints. Getting a cam as close to the stock specs as possible will save a lot of money since you won't need a custom tune. You could just get AFM disabled in the tune for $50 and the rest will just be the mechanical work. Or, you could submit to the slippery slope of WIHIMAW and warm up that credit card. Again, it's best to determine BEFORE you dive in cuz switching up mid-game often costs more money but definitely more time.

 

[Darren2014]

View attachment 344590

Well here they are, which is closest to your original while still keeping VVT? Another thing, you'll only gain about 5-7 horsepower by increasing the lift over .500 with stock 243 heads, hardly worth the strain on the valvetrain IMO.

But! I stayed at a Holiday Inn Express last night, let's ask someone who has already done a cam swap in a 5.3 for their input. @iamdub



No, slides right in, same architecture.

I'm picking up what you're putting down. So a L9H is close enough to "stock" as I'll probably get without having to do extra work or mods, and will still give me a small bit of performance over the cam I am replacing.

 

[swathdiver]

Catch can. It's basically a filter to catch the oil vapors traveling through the PCV system. The oily vapor collects and puddles in the back of the intake manifold and drips into the rearmost combustion chambers. The oil gets burned and cokes up the combustion chambers, sticks piston rings, etc. Pretty much every LS series engine needs a catch can.

It's actually kinda difficult to get coolant where it shouldn't be. Even still, you'd be changing the oil and replacing the coolant after the job so anything that may cross-contaminate will be drained out. The LS engine has a "dry" intake manifold, so there's no coolant mess when you remove it like the older engines. When you pop the heads off, a little coolant will run out of them and into the cylinders. But, it's nothing that can't be soaked up with some shop rags or paper towels. If I'm not pulling the engine, I drain it as much as possible with the lower rad hose removed. Then I jack up the rear of the truck (jack under diff) as high as my jack will go to pour more coolant out through the water pump. Then, with the truck back on the ground, barely any more coolant will run out when I remove the water pump. I use my shop vac over each coolant port to get even more out. After that, it's almost impossible to splash any more coolant out when working on it. I do this with a standard water pump replacement just to minimize the mess. Coolant is very slippery on a shop floor.



LS6 valve springs and a custom tune are the most pertinent and required. But, shaved heads, thinner head gaskets, custom-length push rods, looser stall converter and headers are the extras that aren't totally required but increase power overall, including making up for any lower-end losses the cam may bring. A cam is good and all, but it disrupts a system whose components were all engineered to work together for efficiency and reliability. Changing only the cam yields gains, but the system as a whole is no longer optimal and you end up with sacrifices. The disruption and sacrifices are relatively minimal, especially with "only" a Stage 2, but still less optimal nonetheless.

You have to decide before you tear into it what you ultimately want and are able to do due to time and/or budget and/or service/parts constraints. Getting a cam as close to the stock specs as possible will save a lot of money since you won't need a custom tune. You could just get AFM disabled in the tune for $50 and the rest will just be the mechanical work. Or, you could submit to the slippery slope of WIHIMAW and warm up that credit card. Again, it's best to determine BEFORE you dive in cuz switching up mid-game often costs more money but definitely more time.

Chris, what do you think his best cam choice would be if he wants to stay as close to "stock" as possible? If he didn't want to keep VVT I'd recommend the L33 camshaft myself but you know more about this than I do.

 

[iamdub]

Chris, what do you think his best cam choice would be if he wants to stay as close to "stock" as possible? If he didn't want to keep VVT I'd recommend the L33 camshaft myself but you know more about this than I do.

Close to stock but without AFM? L9H cam.

Close to stock as possible but without AFM and VVT? LQ9 cam.

My choice would be to keep VVT and go with the L9H cam.

 

[wsteele]

Looking at the "LM7" cam TSP offers that works "with or without VVT", it appears to be GM part number 12689035. It does have the same grind spec as the LM7 but unlike the LM7 cam, does appear to have the VVT groove in the bearing journal. It looks like it originally was used in the VVT version 4.8L engines.

Looking around the various sites (TSP, SD Parts, Summit, etc) that offer DOD/AFM Delete kits for stock plug and play deletes, 12689035 seems to be the most common cam offered for a plug and play delete crowd.

 

[Darren2014]

So if I went with the LH9 or L9H cam, would I need to have a tune put on for either besides just having DOD deleted? And as far as VVT goes, would they both be just plug and play or would I have to install a cam phaser limiter? Also do I need to plug the ports that sit under the valley cover when I take it off? And my last question, do I just tuck the wiring for the valley cover away after I replace it with the non DOD one?

 

[iamdub]

So if I went with the LH9 or L9H cam, would I need to have a tune put on for either besides just having DOD deleted? And as far as VVT goes, would they both be just plug and play or would I have to install a cam phaser limiter? Also do I need to plug the ports that sit under the valley cover when I take it off? And my last question, do I just tuck the wiring for the valley cover away after I replace it with the non DOD one?

I would not use the LH9, but rather the L9H. I'm not the authority on it, but I don't believe you'd need a limiter on it. Maybe if the L9H phaser was different than what's in your 5.3, you'd just use that one. Just a guess, though. I'd plug the ports rather than relying on the O-rings to provide all the sealing. Plugging them is cheap insurance to ensure they never leak. I removed the connector from my AFM VLOM, cut out the electrical connections and epoxied over them then plugged it into the harness and zip-tied it to keep it from dangling. This provided a weathertight plug for the harness, in case there was any voltage in the circuit(s).

 

[Darren2014]

Ok so I'm ordering the L9H cam tonight. Specifically #12711967 from LSXeceleration. I'm wondering if I should go ahead and change my valve springs since they have 90k police miles on them and the slight bump in valve lift might be too much for the already worn in valve springs. If so I might as well lap the valves while I have the springs off.

I'm planning on plugging my oil towers, and replacing my valley cover with one from a 4.8. I'm also planning on leaving the oil relief valve in the plan since I'm keeping the high volume oil pump. I'm replacing the push rods while I'm in there. Lastly I'm planning on replacing the seals to the exhaust manifold, air intake, oil pan, timing cover, heads, and valve covers. Anything else I'm missing?