sandking

iTrader: (7)

OK, after some searching, I now have more questions. I have an '07 "LMG" 5.3 AFM, Flex Fuel engine with 799 heads, blah, blah, blah, going in a '72 Blazer. I will have a 224 cam and LT headers the rest will be stock. I was told I need to replace the lifters because of the half of them are AFM lifters (I wont be using the AFM). I was reading up on Caddy lifters vs. LS7 lifters vs. Comp lifters. I have used the Comp R in the past without any issues, but I have read bad things about all of them lately. I am assuming half of my lifters are comparable to the LS7. Can I safely install all new LS7 lifters with this cam or something other? My tunning is limited to 6k RPM. I dont feel I need to spend the money on Morrels for what I have. Any info would be great. Thanks!!

sandking

iTrader: (7)

I know this is like beating a dead horse, but the AFM lifters is what confused me.

SOMbitch

iTrader: (8)

I would go LS7 for your purpose. The caddy lifters are intended for high RPM use an are apparently finnicky as lots of sets have gone down on this board. The Comp R are fine but require a more narrow preload window to get right so consider that. The LS7's are pretty forgiving and have proved over & over again to be reliable to 7K+ so I feel they are the best value for your application.

sandking

iTrader: (7)

Good info, thanks!!

I have heard that the LS7 lifters are typical to all newer LSx style engines, any truth to this?

Droptopws6

iTrader: (13)

Yes, they are the standard now.

sandking

iTrader: (7)

So, assuming that, do I have comparable lifters in my '07?

Droptopws6

iTrader: (13)

GM LS7 Lifters are a direct replacement for all LS based engines. That being said, I'm not sure about whats in your 5.3 now. I have no experience with the 5.3

jwatson

iTrader: (8)

I say go with the ls7's I used them with no complaints, and with your setup im sure they will do good.

sandking

iTrader: (7)

Thats what I will do, thanks guys!!

sandking

iTrader: (7)

Just thinking, whats the difference between the AFM lifters and the standard LS7 lifters? Why couldnt I use the AFM lifters? BTW, I got a 220/220 581/581 Comp Cam if it matters.