So I was guided to these two engines lm7, and or lq9 as a swap idea for a less expensive LS1 swap. Now, these seem to be built for the trucks/suv's so I assume they're heavier in weight, iron over aluminum, but for the prices, I can get a fully assemble 5.3 for $300 plus maybe 80lbs. I think its worth it.
Are the lm7/lq9 based off of the same block as an LS1 is kind of what I'm asking. Cause if so, that should mean I would be able to bolt up most, if not all LS1 items.
Thanks guys!

 

Yes.

Yes, you can.

 

The LQ9 is the way to go. Basically the LQ9 is an iron block LS2. Makes around 400HP/395TQ as I recall. You need to get an LSx intake as the truck intake is too tall to clear the stock hood and the truck accessory setup needs to be changed over to an LS1 style serpentine setup.

 

If you change the heads to #243s, then it's an iron-block LS2. As installed, LQ9s made 345 hp and 380 ft-lbs.
Of the truck versions, the LQ9 is most desirable. Second is an '01-up LQ4, which is the same thing but dished pistons. Avoid '99 and '00 versions.

 

Wow thanks guys, I think this might be what I do seeing I haven't started building my 350 yet, still just a block right now

 

If you stick LM7 heads on an LQ4, the compression is still low enough for pump premium with a stock cam.
LM7 heads are all aluminum, and flow enough air to get you 350 rwhp with an automatic, using nothing more than a TR220 cam, a set of headers, and a tune.
You can't even get aluminum heads for your 350 for what you can get the whole LM7 for. Even with iron Vortec heads on a 350, you're not getting 350 rwhp with an automatic.
The catch of all this is the cost of the harness, and the tune for the engine computer.
The price ends up the same, but with the newer engines, that same money gets you more power, better mileage, cleaner emissions and improved durability and reliability, with a bit less weight.
On the other hand, if you want off-idle torque, the 350 will kill the LM7.