Building an LS3 engine from scratch?
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Building an LS3 engine from scratch?
If you start with a bare block LS3 and are willing to put around 12,000-14,000 into it, how much reliable (i.e., no boom after 25,000 miles) hp would you expect a reputable engine builder to make with it? 550-600RWhp? more/less?
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I'd rather not do FI.
I realize there are a lot of options, but I'm just trying to get a rough baseline of what range I would be looking at with that much money invested. Obviously different builders will use different parts and different shop rates, but it'd be nice having a rough generalization going into this so I know if I'm getting the bum-end of the stick or not.
Ideally I'd like to make as much power as possible, without needing any major maintenance for like 60k (or flat out going boom sooner
)....so I guess by reliable I mean it isn't going to grenade, and I'm not going to have do stuff like pull off the heads every 5k.
FWIW it's mostly going to be street use, so 95% of it's life will be below 3500RPM (so it won't be spending those 60k miles banging off 6600 all day long)
I realize there are a lot of options, but I'm just trying to get a rough baseline of what range I would be looking at with that much money invested. Obviously different builders will use different parts and different shop rates, but it'd be nice having a rough generalization going into this so I know if I'm getting the bum-end of the stick or not.
Ideally I'd like to make as much power as possible, without needing any major maintenance for like 60k (or flat out going boom sooner
)....so I guess by reliable I mean it isn't going to grenade, and I'm not going to have do stuff like pull off the heads every 5k.FWIW it's mostly going to be street use, so 95% of it's life will be below 3500RPM (so it won't be spending those 60k miles banging off 6600 all day long)
Last edited by Tork Stik; Dec 26, 2009 at 03:29 PM.
Safety Car
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Posts: 4,359
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From: Los Alamitos California
St. Jude Donor '09
San
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From: Clinton Township MI
C7 of Year Finalist (track prepared) 2019
Expect
1.4-1.5 hp/ci for a mild street engine
1.5-1.55 hp/ci for a moderate to aggressive street engine
1.55-1.6 hp/ci for a radical race engine
1.6+ for something very exotic
These are for naturally aspirated LS engines. Anybody who tells you otherwise is dreaming or clueless.
1.4-1.5 hp/ci for a mild street engine
1.5-1.55 hp/ci for a moderate to aggressive street engine
1.55-1.6 hp/ci for a radical race engine
1.6+ for something very exotic
These are for naturally aspirated LS engines. Anybody who tells you otherwise is dreaming or clueless.
Safety Car
Joined: Sep 2007
Posts: 4,359
Likes: 6
From: Los Alamitos California
St. Jude Donor '09
Expect
1.4-1.5 hp/ci for a mild street engine
1.5-1.55 hp/ci for a moderate to aggressive street engine
1.55-1.6 hp/ci for a radical race engine
1.6+ for something very exotic
These are for naturally aspirated LS engines. Anybody who tells you otherwise is dreaming or clueless.
1.4-1.5 hp/ci for a mild street engine
1.5-1.55 hp/ci for a moderate to aggressive street engine
1.55-1.6 hp/ci for a radical race engine
1.6+ for something very exotic
These are for naturally aspirated LS engines. Anybody who tells you otherwise is dreaming or clueless.
San
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Thread Starter
Instructor
Joined: Dec 2009
Posts: 183
Likes: 0
Expect
1.4-1.5 hp/ci for a mild street engine
1.5-1.55 hp/ci for a moderate to aggressive street engine
1.55-1.6 hp/ci for a radical race engine
1.6+ for something very exotic
These are for naturally aspirated LS engines. Anybody who tells you otherwise is dreaming or clueless.
1.4-1.5 hp/ci for a mild street engine
1.5-1.55 hp/ci for a moderate to aggressive street engine
1.55-1.6 hp/ci for a radical race engine
1.6+ for something very exotic
These are for naturally aspirated LS engines. Anybody who tells you otherwise is dreaming or clueless.
- not n/a
- I want to run a really aggressive cam; I love the LOPEY LOPEY. No point buying a crate engine and then tearing into it
- I could probably end up with +100ish hp starting with a bare block, comared to the LSA.
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Le Mans Master
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From: Southeast TX
550 to 600rwhp and you're going to spend 95% of your time under 3500rpm? Any engine capable of 550+rwhp is going to run like $hit on the street. It will be fun for a while, but will get old quick. You need to either rethink your power goals or strongly consider F/I. 550Rwhp won't take anything exotic with 8psi blowing into it. It will live a long time too. That, and still retain perfect street manners.
Thread Starter
Instructor
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550 to 600rwhp and you're going to spend 95% of your time under 3500rpm? Any engine capable of 550+rwhp is going to run like $hit on the street. It will be fun for a while, but will get old quick. You need to either rethink your power goals or strongly consider F/I. 550Rwhp won't take anything exotic with 8psi blowing into it. It will live a long time too. That, and still retain perfect street manners.
Le Mans Master
Joined: Dec 2005
Posts: 6,999
Likes: 1,685
From: Southeast TX
I have to disagree with that. I have a 408 (n/a ford 351w stroker) with a racing-style clutch (off/on quatermaster) that makes 500RWhp and while it certainly doesn't have good street manners compared to a factory z06 or viper or civic or whatever factory car you want to insert here, it definately doesn't run like crap. It's just a different driving style, that's all.
. You sound like you know what you're getting into. At 460rwhp n/a, my LS3 vette had more bad manners than what I'm willing to put up with. Tastes differ. You're wanting 90 more rwhp at a minimum. Now, I'm at 670+ with near perfect street manners. I wish I had gone F/I to start with, but it's kind of a big bite to begin with. Cam and heads sound less expensive....and they are if you stop there. Good luck with your build. It sounds like you'll need more cubes and some really good heads to get where you're wanting to go.
Thread Starter
Instructor
Joined: Dec 2009
Posts: 183
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It's OK to agree to disagree. You sound like you know what you're getting into. At 460rwhp n/a, my LS3 vette had more bad manners than what I'm willing to put up with. Tastes differ. You're wanting 90 more rwhp at a minimum. Now, I'm at 670+ with near perfect street manners. I wish I had gone F/I to start with, but it's kind of a big bite to begin with. Cam and heads sound less expensive....and they are if you stop there. Good luck with your build. It sounds like you'll need more cubes and some really good heads to get where you're wanting to go.
. You sound like you know what you're getting into. At 460rwhp n/a, my LS3 vette had more bad manners than what I'm willing to put up with. Tastes differ. You're wanting 90 more rwhp at a minimum. Now, I'm at 670+ with near perfect street manners. I wish I had gone F/I to start with, but it's kind of a big bite to begin with. Cam and heads sound less expensive....and they are if you stop there. Good luck with your build. It sounds like you'll need more cubes and some really good heads to get where you're wanting to go.Call me crazy, but the aspects of 'radical' engines that most people consider ill-mannered - e.g., MASSIVE come lope - I just loooooooove
