cgEvan

iTrader: (1)

I stay on google with "site:ls1tech.com" in the search bar, so please bear with my questions! I'll try not to sound like a complete noob, but I'd like some confirmation on my research and some stuff I couldn't find much info on.

Looking to upgrade the old Mercedes a bit. It's currently running a bone stock LM7 with f-body accessory drive and intake. I have an LS6 and TBSS intake manifolds sitting around, along with a set of 799 heads, and I'd also like to get a cam in there while it's torn apart.

Here are my questions:

1. Which makes better power, the LS6 intake manifold or the TBSS? Both are stock, no port work.

2. With the better intake manifold, 243 heads, and supporting mods, what kind of cam specs do I need to be on the look out for? This is a street driven car, but I want to get some decent power from the 5.3. Coming from a LS1 car, I've heard it's easy to over-cam a 5.3. Is something like the MS3 too big?

3. I know the 243 heads on an LM7 will drop the compression, what's the most I can mill them with a decent sized cam? I've read .035"-.050"

Quicklynx

The 243s will raise your compression a bit, and that is what you want if you aren't going FI. Even if you do go FI they flow better than say the 706s, which I believe is what you have on there now, and the 317s which I see a lot of people change too.

Will the 243 heads fit or is the bore from the 4.8/5.3 too small that the valves hit the deck? I'm looking to slap 243 heads onto a 4.8L so I need this question answered too.
Update:
As for a cam, I have a NSSP cam available with springs, retainers, locks, etc. that I bought from CSP. I bought it used from them w/2200 miles on it and never installed it. It's just been sitting now that I'm going a different route. I usually am not one for buying used valvetrain pieces, but it's coming from a shop that is pretty darn stand up, and I trust them.

I see guys put this cam in the 5.7L GTOs and make impressive power. As for the 5.3L I don't know how it would work. Maybe shoot Andrew or Andy from Complete Street Performance an e-mail.