Cam Swapping W/ Active Fuel

[07fireball]

I have a 07 gmt-900 with a 5.3 flex motor and would like to know how much lift I can stuff in it without disabling the active fuel system, I realize that this is a bit backwards that I'm talking about stuffing a big cam and trying to keep my economy but the fact is I just want it to work like factory, even if my economy dives. I was going to just swap rockers and leave it at that but I think I would rather do a hot cam if its possible. Does anyone know how much lobe lift is too much for the lifters to de-activate, any info or even a good place to look would be helpfull thanks.

[66nova]

I don't know the specifics but I know you have to run a cam designed to run with AFM. You can't just go pick one. I quite certain there is more to it than just lift.

 

Do you want a cam for the sound or the performance? If you want the performance, then Do you have a custom tune yet?

 

I would try that before you tear into the engine if you are still worried about AFM.

[07fireball]

for the performance, I'm definately going to get one first but Im trying to get my ducks in a row for a tune first, I want to put on the custom mid length headers that I have, and ditch the cats, do a tune and the cam, all at once to reduce down time since my other truck is down as well

[98 Z71 SLT]

You would be better off completely disabling the AFM system...which would involve a custom tune

 

the AFM system is EXTREMELY PICKY about any engine misfires. We all know that with a hot-cam you will have misfires all the time.

 

Then you also have to take into consideration how much lift the AFM lifters can handle. In STOCK FORM these lifters are giving major troubles already.

 

I'd be sending e-mails to major cam companies AND tuning companies...see what they have experienced and for sure..let us know!

 

It may be worth your while just to leave the engine internals in stock form,. do your headers, do a CAI kit, and a tune. You'll see results with those items alone.

[erskine]

yes they make AFM camshafts, but i would just get ride of it and get a custom cam for the mods your going to get or have

[Jennabear]

I would probably stick around 112-115LSA.

[VR021302]

I thought someone posted about a cam made just for AFM, it may have been for the 6.0 though.

[Jennabear]

In all honesty, the best thing to do, is narrow down the cam vendor you want to go with, and call them. They will know exactly what will work best for your application and will suggest the one that you should be looking into.

[txab]

+1

[hubob]

+1

 

 

I have an 08 Silverado 5.3L w/ AFM and I put in a new Comp cam but I removed the AFM lifters and replaced them with high performance lifters. Comp Cams told me if I didnt put in new lifters with the new cam they would not warranty the cam plus Im not sure how many miles are on your truck but using used lifters can cause problems. I would recommend just doing away with the AFM. When you get a custom tune they can turn it off.