LM7 vs l33
Thread Starter
Staging Lane
Joined: Oct 2012
Posts: 55
Likes: 1
LM7 vs l33 I have a few spare parts and want to help a
friend with a ls build/swap. I have a lm7 that needs to be rebuilt. I also have an ls1, a ls4 , and an ls2 intake , an ls1 cam, a late ls6 cam. I also found a good deal on a L33. I am just wondering.
1- do I always need to replace pistons due to the piston slap issue on higher mileage engines?
2- Will the L33 make more power? A lot? I am trying to figure out if it would be worth the extra $700.
3- I would assume I should use the ls6 cam
over the ls1 or stock cam?
4-what intake should I use. The truck intake is ugly
5- is torque plate honing all that important or is a standard ball hone ( bore if needed) good.
6- what kind of HP can I expect
thanks
friend with a ls build/swap. I have a lm7 that needs to be rebuilt. I also have an ls1, a ls4 , and an ls2 intake , an ls1 cam, a late ls6 cam. I also found a good deal on a L33. I am just wondering.
1- do I always need to replace pistons due to the piston slap issue on higher mileage engines?
2- Will the L33 make more power? A lot? I am trying to figure out if it would be worth the extra $700.
3- I would assume I should use the ls6 cam
over the ls1 or stock cam?
4-what intake should I use. The truck intake is ugly
5- is torque plate honing all that important or is a standard ball hone ( bore if needed) good.
6- what kind of HP can I expect
thanks
TECH Fanatic
Joined: Dec 2019
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1. Only if they have piston slap...
2. L33 has flat top pistons, a block that is 100 lbs lighter, better heads/cam from the factory, and depending on the year, better rods/timing chain/lifters.
3. Yes.
4. One that you don't think is ugly.
5. I usually just ball hone, but only if it needs it. My last few engines had great crosshatching.
6. Depends on which engine you decide to go with, what intake, what cam, etc.
2. L33 has flat top pistons, a block that is 100 lbs lighter, better heads/cam from the factory, and depending on the year, better rods/timing chain/lifters.
3. Yes.
4. One that you don't think is ugly.
5. I usually just ball hone, but only if it needs it. My last few engines had great crosshatching.
6. Depends on which engine you decide to go with, what intake, what cam, etc.
TECH Senior Member
Joined: Jun 2016
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From: Central Cal.
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TECH Senior Member
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From: Central Cal.
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Verdad Gallardo Who cares what cam it has in it? It’s an alloy block with flat top full floating pistons with the same heads as the LS6. With a big cam, it will easily make 405bhp. The alloy block already has all the provisions for F-body accessories and timing chain dampener, no need for drilling nonsense - assuming there’s even enough material in the iron block. The LM7 is not even in the same league as the L33. You’d be a fool to pass up an L33 for an LM7.
TECH Senior Member
Joined: Jun 2016
Posts: 22,308
Likes: 3,625
From: Central Cal.
Who cares what cam it has in it? It’s an alloy block with flat top full floating pistons with the same heads as the LS6. With a big cam, it will easily make 405bhp. The alloy block already has all the provisions for F-body accessories and timing chain dampener, no need for drilling nonsense - assuming there’s even enough material in the iron block. The LM7 is not even in the same league as the L33. You’d be a fool to pass up an L33 for an LM7.
You made a very general statement that the L33 is a 5.3L LS6. One of the components that defines what an LS6 is, is the cam
And having to drill ONE hole in an LM7 ?? Big deal...