Lm7
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Lm7 Alright I'm in the army so I got plenty of time to do research but I know next to nothing about cars but I have plenty of buddies who are mechanic junkies and love working on cars so I have them to help guide me as well. They told me to come onto the forums to look into the build I currently want to do. So I want to do a 700 hp LM7 build I'm aware it is likely going to need to be boosted. To handle 700 hp what would I need to do to the motor. I've found online that the block is normally good for 800+ so what would need to be done with it. If its at all possible I would love to have a choppy cam. I don't really have a budget in mind currently because this project is going to be more along the lines of work on it when I have the chance and the money to buy the parts required I already have a daily driver so I'm not really rushed to get the build done. i want something that can handle 700 reliably. I currently plan on finding a beat up 77 Camaro or something similar to swap the LM7 in to. If i go with something older I plan on swapping drums to rotors but besides that what should I do to make the suspension deal with 700 hp. I would also prefer the transmission be a 6 speed manual
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Get a 2004+ gen 3 engine that will have the stronger rods in it, and you won't have to do anything to it to make it handle 700 reliably. Even the gen 3 engines will handle 700 forever, but the margin for error in the tune will be smaller.
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Well what could I do to extend the margin of error. As I said I want something that will reliably handle 700 if the tune being off a little blows the engine than I'd rather spend a little more time and money to make sure the engine can handle the tune being a bit off.
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I'll talk to my buddy who builds his cars about the suspension and disc do you have any recommendations for a 6 speed manual tranny that can handle 700?
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I've made ~900 wheel on an early gen 3 engine with the weaker rods that ran like that for several years before I pulled out the whole setup and sold it.
I ran it on E85 with a setup focused on top end power at the sacrifice of peak torque. I don't think it would have survived on pump gas.
I made similar power on a gen 4 aluminum block 5.3 with the stronger rods on pump 93 and water/meth, and that setup was all about making as much torque as possible.
It is a lot easier to trust the engines with the stronger rods, but that doesn't mean you should count out the earlier engines.
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Less aggressive tune, better fuel, a good intercooler, water/meth injection, various combinations of each, etc.
I've made ~900 wheel on an early gen 3 engine with the weaker rods that ran like that for several years before I pulled out the whole setup and sold it.
I ran it on E85 with a setup focused on top end power at the sacrifice of peak torque. I don't think it would have survived on pump gas.
I made similar power on a gen 4 aluminum block 5.3 with the stronger rods on pump 93 and water/meth, and that setup was all about making as much torque as possible.
It is a lot easier to trust the engines with the stronger rods, but that doesn't mean you should count out the earlier engines.
I've made ~900 wheel on an early gen 3 engine with the weaker rods that ran like that for several years before I pulled out the whole setup and sold it.
I ran it on E85 with a setup focused on top end power at the sacrifice of peak torque. I don't think it would have survived on pump gas.
I made similar power on a gen 4 aluminum block 5.3 with the stronger rods on pump 93 and water/meth, and that setup was all about making as much torque as possible.
It is a lot easier to trust the engines with the stronger rods, but that doesn't mean you should count out the earlier engines.
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I also couldn't find the drum brake conversion on that site.
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Yeah I've been doing research but apparently not a whole lot of people are laying out their builds of something similar so I'm doing research and asking questions at the same time. I've driven decently fast vehicles I drove my buddies truck for awhile it's pushing 400 and it's a single cab. My other buddy has a speed 3 that he said he's gonna let me drive once he gets the boost leaks figured out and it'll be pushing right around 600. I honestly plan to drive the car pretty tamely until I get used to it but I still want it to have the potential of pushing 700 so I can drive it on reduced boost and gradually work my way up to 700. Since I want it to have the ability to push 700 I want to build it as if it's pushing 700 so that way when I'm comfortable I can push it to 700 and not worry about anything blowing up.
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LISTEN and Watch for KR, Retard spark until the knock is gone.
Yeah I've been doing research but apparently not a whole lot of people are laying out their builds of something similar so I'm doing research and asking questions at the same time. I've driven decently fast vehicles I drove my buddies truck for awhile it's pushing 400 and it's a single cab. My other buddy has a speed 3 that he said he's gonna let me drive once he gets the boost leaks figured out and it'll be pushing right around 600. I honestly plan to drive the car pretty tamely until I get used to it but I still want it to have the potential of pushing 700 so I can drive it on reduced boost and gradually work my way up to 700. Since I want it to have the ability to push 700 I want to build it as if it's pushing 700 so that way when I'm comfortable I can push it to 700 and not worry about anything blowing up.
cars also arent built by a recipe, you still have to know how to do the work and figure things out for yourself
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LM7 doesn't seem to be a very common build from what I've been able to find especially pushing an LM7 for 700 WHP in a 77 Camaro.
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From: Central Cal.
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The LC9 is the most produced LS. And it's the most common swapped. It's as I've stated I posted this because I can't find good information to figure out what I need to do to a LM7 because either people aren't doing it, aren't really explaining what they did to it, or in forums someone posts to ask a question and some guy responds with "you don't need 700" or whatever
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The LC9 is the most produced LS. And it's the most common swapped. It's as I've stated I posted this because I can't find good information to figure out what I need to do to a LM7 because either people aren't doing it, aren't really explaining what they did to it, or in forums someone posts to ask a question and some guy responds with "you don't need 700" or whatever
There are far more cast iron blocks of both the Gen III (LM7 & L59) and Gen IV (LY5, LMG & LMF) persuasions. They all went into light trucks
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Last edited by sbrking; Feb 8, 2025 at 09:36 PM.
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What are your production number sources?
Among GM LS truck engines, iron block engine production is a multiple of aluminum block engine numbers.
You admit not knowing **** about engines. The same could be said about you not knowing where or how to research LS engine info, especially where it pertains to production numbers.
Among GM LS truck engines, iron block engine production is a multiple of aluminum block engine numbers.
You admit not knowing **** about engines. The same could be said about you not knowing where or how to research LS engine info, especially where it pertains to production numbers.
