Upgrades to 5.3 LC9

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TexasLandCruiser

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Currently have a Erod crate motor and ready to put a little ass end under it. A lot of opinions but what I was able to gather is do LSXRT truck manifold, fuels rails and injectors, DOD VVT delete and Holley harness. Ditch my cats and simplify. Goal is to get it up to 400hp. Feedback on 1st, 2nd, 3rd.
Thanks
 
400whp with a 5.3 through an auto? You can pick up some power with E85 and tuning but you’re going to need a lot more then that for those kind of gains. None of the things you listed will make any more power.
skip the intake manifold because that will absolutely be a waste of money.

what torque converter and axle gears do you have currently?
The right converter and a little more gear will make it feel way faster.

What is the fastest vehicle you have driven? 400whp is a lot in any vehicle. Your goal may be a bit lofty
 
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400whp with a 5.3 through an auto? You can pick up some power with E85 and tuning but you’re going to need a lot more then that for those kind of gains. None of the things you listed will make any more power.
skip the intake manifold because that will absolutely be a waste of money.

what torque converter and axle gears do you have currently?
The right converter and a little more gear will make it feel way faster.

What is the fastest vehicle you have driven? 400whp is a lot in any vehicle. Your goal may be a bit lofty
My last 2 track cars were LSA platforms running 1000hp however charged. That was easy. However I understand it’ll be a combo that’ll have to bump the numbers. 75 hp out of a normally aspirated 5.3 shouldn’t be impossible. I do like your though out of converter and gears.
 
My last 2 track cars were LSA platforms running 1000hp however charged. That was easy. However I understand it’ll be a combo that’ll have to bump the numbers. 75 hp out of a normally aspirated 5.3 shouldn’t be impossible. I do like your though out of converter and gears.

picking up 75 should be pretty easy with a $250 cam and a converter. But that won’t put 400 to the ground through a auto, offset T-case and 33” tire.

LSA blower or a 78/75 turbo would be great if you wanted to make some real numbers but probably at the cost of your 4l60
 
picking up 75 should be pretty easy with a $250 cam and a converter. But that won’t put 400 to the ground through a auto, offset T-case and 33” tire.

LSA blower or a 78/75 turbo would be great if you wanted to make some real numbers but probably at the cost of your 4l60
I appreciate the feedback, you always shoot it straight. I saw you turbo’d yours, would you have done anything different?
 
I appreciate the feedback, you always shoot it straight. I saw you turbo’d yours, would you have done anything different?

I haven’t turboed my land cruiser yet, I have a handful of other turbo-LS cars/trucks though
 
picking up 75 should be pretty easy with a $250 cam and a converter. But that won’t put 400 to the ground through a auto, offset T-case and 33” tire.

LSA blower or a 78/75 turbo would be great if you wanted to make some real numbers but probably at the cost of your 4l60
At best I’m 300 to the crank, yeah 400 to the wheels especially all that heavy metal under would be a challenge with entry level stuff. Was talking about crank numbers
 
What size tires do you have? What is your differential gear ratio? The 3.70 gears will make it struggle. What Trans? Looking at your list I see very little in my opinion that will make a big difference. Vvt will help with torque down low, so I wouldn't mess with removing it. A aftermarket truck cam and a dyno tune would be as far as I would go. If you put some valve springs in it with the bigger cam you can Rev it further. I believe they make vvt cams aftermarket. Personally I would not mess around and do forced induction of your choice. You have the bottom end for it. Just need the fuel. The other option is just sell the 5.3 and put a bigger Ls in it.
 
What size tires do you have? What is your differential gear ratio? The 3.70 gears will make it struggle. What Trans? Looking at your list I see very little in my opinion that will make a big difference. Vvt will help with torque down low, so I wouldn't mess with removing it. A aftermarket truck cam and a dyno tune would be as far as I would go. If you put some valve springs in it with the bigger cam you can Rev it further. I believe they make vvt cams aftermarket. Personally I would not mess around and do forced induction of your choice. You have the bottom end for it. Just need the fuel. The other option is just sell the 5.3 and put a bigger Ls in it.
If I recall 4.11 gears. Tires are 33x10 TKO2. I spoke to my LS engine builder who built several for me and he suggested and reminded me about my transmission Compushift and may need to be re-tuned. I’d forgot one of my issues is it short shifts. Also mentioned same as you, the VVT would be a nominal difference being only 10k miles on it and performance numbers as advertised. I think there’s life in it and more I think About it need to focus on shift.
 
If I recall 4.11 gears. Tires are 33x10 TKO2. I spoke to my LS engine builder who built several for me and he suggested and reminded me about my transmission Compushift and may need to be re-tuned. I’d forgot one of my issues is it short shifts. Also mentioned same as you, the VVT would be a nominal difference being only 10k miles on it and performance numbers as advertised. I think there’s life in it and more I think About it need to focus on shift.
What transmission do you have? Do you have tow haul mode wired up? You could have tow haul mode tuned as a performance shift tune and regular mode as a economy smooth shift tune. I don't know what camshaft the LC9 has. But some upgraded valve springs and a tune you could spin it faster which will get you to higher rpm when it grabs the next gear. My redline is set to 6300 which is a tad conservative. It sounds real good at those rpms.
 
What transmission do you have? Do you have tow haul mode wired up? You could have tow haul mode tuned as a performance shift tune and regular mode as a economy smooth shift tune. I don't know what camshaft the LC9 has. But some upgraded valve springs and a tune you could spin it faster which will get you to higher rpm when it grabs the next gear. My redline is set to 6300 which is a tad conservative. It sounds real good at those rpms.
I think I found the issue. I have the Compushift 2 computer and it’s short shifting. The shift points bump pretty hard but rpms in each gear are only getting up to 4500 or so, I hate the way it’s setup but didn’t think about that. It’s the 4l65 trans. I need to find the manual to reset the shift. As for Cadillac mode or tow I’d say it’s set in economy mode as reserved as its acting. 411 gears I read somewhere in the books not sure on cam
 

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