Cleaning Intake Valves

[SilverSH0]

I know it's well known that due to direct injection a lot of carbon buildup happens on the back of the intake valves. I've been looking to install meth injection so I decided to break out the fiber optic camera and check out the back of the valves. What I found wasn't what I was hoping.....TONS of carbon buildup. So much buildup that it appeared there were "boils" of carbon bubbles. I don't know how to explain it and the pictures didn't really come out. Basically there were lots of "bubbles" of carbon on the back of the valves. My concern is if I start spraying meth it will start to dissolve the carbon and these bubbles will break free and then go through the engine (potentially scraping the inside of the engine).

That got me into searching for how to clean the valves and I came across several people that have done it to M series BMWs. Essentially it involves removing the intake and walnut blasting the back of the valves (when the valves are closed). Has anyone done anything similar to clean the valves? Is the intake manifold really as simple to remove as it looks? I'm hoping to clean the back of the valves and then allow the meth to keep it from building up again in the future.

 

[6500rpm]

I've never pulled the intake on our engine but it seems fairly simple. From what I understand about walnut shell blasting you'd need to buy or make a plate to bolt over the intake runner on the head with an opening to blast the media in and a second opening to suck it out with a shop vac. I'm not sure what pressure to run on the media for the best performance. Sounds like a better part of a day but it's probably the best option. I like the idea of the Meth injection, wonder once you have it tuned properly how hard it is to switch between Meth and non meth tunes if you want to run it as part of a maintenance routine rather than purely performance.

 

[SilverSH0]

I've never pulled the intake on our engine but it seems fairly simple. From what I understand about walnut shell blasting you'd need to buy or make a plate to bolt over the intake runner on the head with an opening to blast the media in and a second opening to suck it out with a shop vac. I'm not sure what pressure to run on the media for the best performance. Sounds like a better part of a day but it's probably the best option. I like the idea of the Meth injection, wonder once you have it tuned properly how hard it is to switch between Meth and non meth tunes if you want to run it as part of a maintenance routine rather than purely performance.

I've seen several tutorials and they almost always center around M series BMWs. I'm assuming that's due to it's popularity and how long they've been using DI (plus they actually recommend having it done as normal maintenance). I've seen a couple people who use old radiator hoses to act as the seal for the intake runner. Then they simply cut a slot in the top to feed in the blaster. With the design of our V6, it looks pretty simple to get the intake off.

I plan on using meth for performance with the added benefit of keeping things clean. However, I would imagine there is minimal cleaning difference between meth injection and simple water injection. I've worked on a couple tractors with a slight head gasket leak (leaking coolant into the cylinder) and when they were fixed the cylinder that was leaking water/coolant was CLEAN. If you went with the water injection route, I doubt you would need a special tune. But even with meth injection I think it would be as simple as swapping in a 93 octane tune and cutting power to the meth controller (though I have not tried or worked with meth injection yet).