the 8th digit in the vin is a "B"

 

Guys, I really gotta know- did any of the 2007 Classic Crew Cabs get the L33 and how would I know by the VIN. Thank you so much...........

edit; thanks Trev, you rock.............

 

Well- look as I might, there is no 2007 CC to be had with an L-33. But that's OK- because aren't the injectors on the L-59 bigger anyways for the flex- fuel? That would give me some lattitude with bigger cams/ punching out the block. Thanks for bearing with my guys, I'm tryin' to put it all together as I have brain injuries from a young age..................

P.S. Oh yeah- and did'nt the 2006- 07's get like the 4L65/ 70e.............

 

I noticed a few things not mentioned.
One of the biggest differences between an LM7 and L33 are the cylinders heads. The LM7 uses the same heads as the 4.8 (LR4) where as the L33 uses 799's which are identical casting to the 243s found on the Ls2 and Ls6 in the corvettes, which have heavier valve springs and hollow exhaust valves not found on the 799 heads. Another major difference is the pistons. The LM7 uses dished piston and the L33 uses the same flat top pistons found in the LR4 which gives it a bump from 9.5:1 to a 10.0:1 and a cam only used in the L33 which someone already quoted the specs for I believe. The general claims 310 hp and 335 lb·ft.

The L33 was only used in 2005-2007 extended cab 4x4 Sierras and Silverados. Less then 5000 trucks in 05 had the L33.

 

nothing like digging up a 4 year old thread.

 

Love it. Still rocking my L33 with Radix. That compression ratio I read to be is 9.9:1 but that's a split hair.

The added compression makes for some hard to tune out KR on light throttle low loads. In mine anyways.
Say you are going 55mph on a light incline and want to pass by another car without kicking down a gear, this is when it happens very briefly.

Not audible. We see it in the scans. Its just when we crack the throttle.

See my sig for Dyno numbers stock and after. I put the blower on @ 5K miles. @ 70 now.

 

And what is so terrible about it ? I enjoyed re-reading it .

Smartass comments are better posted on GMFS if you so feel the need again .

 

This is one of the fine reasons I love this forum. The help and support here is top notch.
Any info on my beloved L33 I cherish.

80 Lbs lighter with the added hardware and tweaks has been a real treat for me.

 

Yup ! Def some of the best info is here and good guys wanting to help , that's what makes this place great .

It's so cool to see you post in this thread back then and also now with the same setup still going strong !!! Congrats !

I still have a nice L33 on my stand just waiting to go in something !

 

Thanks, And I do not exactly baby it either.

The only thing with the L33 I find hard to get used to is the cold start engine noise.
From day one when you fire her up cold you can hear it.
In summer its almost inaudible and does not last even one minute.
In winter its more audible and takes longer to quieten down.

If you are not as mechanically obsessed as the likes of us you may not even notice it.

I know the L33 is a 6-bolt main config. Are the LM7's also 6-bolt mains?

I just updated my Blog page on her in my signature to include the improvements on the new Heat Exchanger. I also noted the insulating of
the coolant hoses and moved the pump and reservoir out of the engine bay heat. Some of the pics linked in the heat exchanger section show it. The pump is behind the slots in the bumper.

I wish I had a spare L33 to breath on.