Why build a 408 over a LS7?
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Why build a 408 over a LS7?
I was researching building a 408 for my car(if I were to blow it). To do it right it would probably cost me $15,000 +/-(realistically).
Why not just buy a LS7 and put a mild cam in it? I saw in Car Craft a few months back there was an LS7 with a "mild" cam(builder wouldnt release exact cam specs). But the car dyno'd around 700hp on an engine dyno. So figure after all the necessities are bolt on and put in a car it would probably dyno roughly 550whp +/-.
So tell me why I would want to build an Iron(or Aluminum) 408 over a LS7. I would think realistically you could build the LS7 for the same or slightly more than the 408 and have a much better combo.
EDIT: This combo would be all motor no power adders.
Why not just buy a LS7 and put a mild cam in it? I saw in Car Craft a few months back there was an LS7 with a "mild" cam(builder wouldnt release exact cam specs). But the car dyno'd around 700hp on an engine dyno. So figure after all the necessities are bolt on and put in a car it would probably dyno roughly 550whp +/-.
So tell me why I would want to build an Iron(or Aluminum) 408 over a LS7. I would think realistically you could build the LS7 for the same or slightly more than the 408 and have a much better combo.
EDIT: This combo would be all motor no power adders.
Last edited by BLK85; 10-11-2008 at 12:58 AM.
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I've heard the LS7's aren't ideal for boost because of the small cylinder walls, because the bore is big for the block. Not sure what the threshold is, but I hear that's why boost guys go with a ~400 setup.
A dude the other night was talking about how Lingenfelter kept cracking LS7 blocks when they were trying throw twins on it. Also heard that that's why the LS9 is based off the LS3, not the LS7.
I obviously don't know too much on the subject though, so hopefully someone will correct me if I'm mistaken... lol
A dude the other night was talking about how Lingenfelter kept cracking LS7 blocks when they were trying throw twins on it. Also heard that that's why the LS9 is based off the LS3, not the LS7.
I obviously don't know too much on the subject though, so hopefully someone will correct me if I'm mistaken... lol
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700hp at the flywheel without any accessories. Read the rest and I think realistly 550whp would be the outcome(with AC, Alternator, etc.).
Yes Im talking $15k just for the engine. If you dont believe me try building it yourself(just pricing everything) I got around 10k. Then I talked to a friend and he added a few grand to it. Figure 15k(at least) starting form a short block building it with good components(AFR heads, Good Crank, etc.) and thats not installing it. Im talking all motor no power adders.
Yes you could have a lot of power for cheaper but Im thinking reliable HP. How long would a LS1(346ci) last at 700hp(flywheel)? Im not talking RWHP with the 700hp figure.
What I would want from a car would be something I could drive daily. Something with a fair amount of power something with everything working(AC, Radio, etc.). Something I could drive 500 miles and not get a headache from the exhaust note, something I could get 20+ mpg(highway).
What I would want from a car would be something I could drive daily. Something with a fair amount of power something with everything working(AC, Radio, etc.). Something I could drive 500 miles and not get a headache from the exhaust note, something I could get 20+ mpg(highway).
Last edited by BLK85; 10-13-2008 at 08:16 AM.
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I've heard the LS7's aren't ideal for boost because of the small cylinder walls, because the bore is big for the block. Not sure what the threshold is, but I hear that's why boost guys go with a ~400 setup.
A dude the other night was talking about how Lingenfelter kept cracking LS7 blocks when they were trying throw twins on it. Also heard that that's why the LS9 is based off the LS3, not the LS7.
I obviously don't know too much on the subject though, so hopefully someone will correct me if I'm mistaken... lol
A dude the other night was talking about how Lingenfelter kept cracking LS7 blocks when they were trying throw twins on it. Also heard that that's why the LS9 is based off the LS3, not the LS7.
I obviously don't know too much on the subject though, so hopefully someone will correct me if I'm mistaken... lol
Again dont want to boost it. Just all motor.
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if you taked to a builder that you "trust" and he told you 15K for a 408, you need to go somewhere else, 12k max when your talking all motor, thats with tfs or afr heads, jessel rockers callies internals, fast intake, kooks headers, and tuned. and all installed
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TSP 402(LS1)/408 LQ9 Long block " Has been tested to make over 800rwhp on nitrous & up to 550rwhp N/A!" - $6,475.00 http://texas-speed.com/shop/item.asp?itemid=45
TSP ported oil pump- $139.99
F.A.S.T 92mm intake & TB combo Add - $1,099.00 (or the L76 intake w/39lb injectors for the exact same price)
NGK TR55-IX Iridium Spark Plugs -$7.99.00 (x8)
*RAM Powergrip HD clutch -$419.99 (Only if needed).*
Turn old flywheel -$25.00 ????
Recharge A/C system- $65.00???? (Got mine for free)
Slap all your old **** on there, put the damn thing in yourself. Another $500.00 or so for a good tune! I come up with aprx. $8,727.90. For under 10 grand you can have one badass street motor IMHO!!
Even if you PAY someone to put the **** in, you're still coming out WAY on top compared to doing an LS7 swap ($9,850.00 just for the LS7 "long block"). You can also argue about the heads not being good enough or other "hidden costs" (which I am very well aware that there WILL BE, but not $6,273 worth) or whatever you want. Bottom line, if you spend 15 grand on a 402/408 N/A street motor....I feel you got ripped. You give me 15 G's and I'll get you one hellofa motor (then pocket the other 5-6 thou)!!!
My .02
TSP ported oil pump- $139.99
F.A.S.T 92mm intake & TB combo Add - $1,099.00 (or the L76 intake w/39lb injectors for the exact same price)
NGK TR55-IX Iridium Spark Plugs -$7.99.00 (x8)
*RAM Powergrip HD clutch -$419.99 (Only if needed).*
Turn old flywheel -$25.00 ????
Recharge A/C system- $65.00???? (Got mine for free)
Slap all your old **** on there, put the damn thing in yourself. Another $500.00 or so for a good tune! I come up with aprx. $8,727.90. For under 10 grand you can have one badass street motor IMHO!!
Even if you PAY someone to put the **** in, you're still coming out WAY on top compared to doing an LS7 swap ($9,850.00 just for the LS7 "long block"). You can also argue about the heads not being good enough or other "hidden costs" (which I am very well aware that there WILL BE, but not $6,273 worth) or whatever you want. Bottom line, if you spend 15 grand on a 402/408 N/A street motor....I feel you got ripped. You give me 15 G's and I'll get you one hellofa motor (then pocket the other 5-6 thou)!!!
My .02
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In the latest issue of GMHTP they have a multi-page write-up on different priced stroker short-blocks. For reference, there's a 408ci (LQ9) shortblock in the article for $4,800 using Callies and Wiseco rotating components, good hardware and has a 90 day warranty.
So, $4,800 for a shortblock. Maybe spend $1,500 on some budget cylinder heads with decent dual valve springs then add a stout custom camshaft (~$425) and FAST 92/92 setup ($1,200-1,300). Add a fuel pump for $250 and some larger fuel injectors. Even with the cost of coolant, gaskets and miscellaneous other items, you'd be WELL under $10k. You should have more than enough left over to buy a decent clutch.
Just a thought.
- Dustin
So, $4,800 for a shortblock. Maybe spend $1,500 on some budget cylinder heads with decent dual valve springs then add a stout custom camshaft (~$425) and FAST 92/92 setup ($1,200-1,300). Add a fuel pump for $250 and some larger fuel injectors. Even with the cost of coolant, gaskets and miscellaneous other items, you'd be WELL under $10k. You should have more than enough left over to buy a decent clutch.
Just a thought.
- Dustin
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