iron 5.7 or aluminum 5.7?
#21
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I agree with predator on this. An ls1 block will hold power just fine for 90% of builds out there given the tune is good. I myself went with a iron block 347 because i could get it for 75 bucks rather then 300+ for an ls1. if you looking for an affordable block to get you where you want the iron will do great and hold up well.
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It doesn't take much pregnition or detonation to crack the sleeves in an LS1 block. With an iron block, however, you would almost have to try to run 87 octane with 30psi of boost to crack the block.
The iron block is simply more forgiving if you trust your engine to the wrong tuner.
The iron block is simply more forgiving if you trust your engine to the wrong tuner.
Knock will kill any motor period. I'm not even sure what you are implying here.... That the iron block will take more knock before it blows? Your motor is NOT suppose to knock in the first place.
You are going about this the wrong way.
#23
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You will crush/spin your rod bearings with knock. Then the block will crack after your rods go right through it.
Knock will kill any motor period. I'm not even sure what you are implying here.... That the iron block will take more knock before it blows? Your motor is NOT suppose to knock in the first place.
You are going about this the wrong way.
Knock will kill any motor period. I'm not even sure what you are implying here.... That the iron block will take more knock before it blows? Your motor is NOT suppose to knock in the first place.
You are going about this the wrong way.
Am I the only one that read that the OP is worried more about reliability than weight?
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I agree with predator on this. An ls1 block will hold power just fine for 90% of builds out there given the tune is good. I myself went with a iron block 347 because i could get it for 75 bucks rather then 300+ for an ls1. if you looking for an affordable block to get you where you want the iron will do great and hold up well.
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There is no such thing as reliability with a bad tune. If you are breaking your block, you have other issues to deal with. A good tuner is more important then choosing between an iron or aluminum block.
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I have a good tuner down here in phx that knows his lsx motors so I'm good there guys. Lookin for performance but most importantly reliabilty plannin on a big cam and 100 shot of nitrous
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You don't have to stroke an iron block to make it a 347. You just bore the cylinder out to 3.9xx" and use a stock 3.622" crank. That what I'm doing.
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Sure there is. Poor tuning doesn't always destroy an engine, its the REALLY poor tuning that does. Like I said earlier, I have personally seen an engine with detonation issues that cracked the sleeve of the block before the piston gave up. I would consider a block that doesn't break before the OEM piston does to be more reliable than one that does, wouldn't you?
You don't have to stroke an iron block to make it a 347. You just bore the cylinder out to 3.9xx" and use a stock 3.622" crank. That what I'm doing.
You don't have to stroke an iron block to make it a 347. You just bore the cylinder out to 3.9xx" and use a stock 3.622" crank. That what I'm doing.
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Well if the piston in the adjacent cylinder came apart, and the piston in the cylinder that cracked showed damage from detonation, there is no reason to believe aliens did it. That cylinder had detonation issues, no doubt about that, and as destructive as detonation is, there really is no reason to suspect anything else.
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I feel that it depends on the tune. I know a couple of dudes that are making over 1,000whp. with aluminum blocks (however, they are not LS1). It couldn't hurt to go iron if you are shooting for huge power numbers. Iron won't flex as much under extreme heat & pressure like aluminum will.
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No power wit this block is a little over 450rwhp that id like 2 get. I'm goin 2 build a lq9 as well. Once that's done I'm putting this in my fox and lq9 on my nova
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Go ahead and explain how a tune that blows up the engine isn't a poor tune.
Well if the piston in the adjacent cylinder came apart, and the piston in the cylinder that cracked showed damage from detonation, there is no reason to believe aliens did it. That cylinder had detonation issues, no doubt about that, and as destructive as detonation is, there really is no reason to suspect anything else.
Well if the piston in the adjacent cylinder came apart, and the piston in the cylinder that cracked showed damage from detonation, there is no reason to believe aliens did it. That cylinder had detonation issues, no doubt about that, and as destructive as detonation is, there really is no reason to suspect anything else.
I won't bother explaining a poor tune vs. an aggressive tune. Its just plain silly for me to try and explain that especially if you do not tune your own cars.
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The clue to the destroyed block was detonation and yet you blame the aluminum block? Why? How did you reach that conclusion? The suspect was the tune as YOU clearly mentioned yourself.
I won't bother explaining a poor tune vs. an aggressive tune. Its just plain silly for me to try and explain that especially if you do not tune your own cars.
I won't bother explaining a poor tune vs. an aggressive tune. Its just plain silly for me to try and explain that especially if you do not tune your own cars.
Don't try to insult my intelligence to cop out of having to back up your BS. I'm not a tuner, but I've had enough experience in a dyno cell with the likes of Don Bailey and DaVnci to keep up with anything you have to say. So again, go ahead and explain.