408CI boost question
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408CI boost question
hey all,
i am wondering how much boost you could throw at a forged 408. im talkin the right rods, crank, pistons etc...
thanks guys, i appreciate the help
i am wondering how much boost you could throw at a forged 408. im talkin the right rods, crank, pistons etc...
thanks guys, i appreciate the help
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thats another thing, i have no idea what heads i would be running. ive always been an NA guy so this world of boost is all new to me. i guess id throw on sme L92 or afr 225s?? i really dont know. do u have an idea what a good set of heads are for a motor like that?
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that too, but im really asking how much a lq4 408 can handle as far as boost goes. id like to se 800-1000rwhp if i go this route
are u running an aluminum 402? i dident think the aluminum block could handle that much boost
thats another thing, i have no idea what heads i would be running. ive always been an NA guy so this world of boost is all new to me. i guess id throw on sme L92 or afr 225s?? i really dont know. do u have an idea what a good set of heads are for a motor like that?
are u running an aluminum 402? i dident think the aluminum block could handle that much boost
thats another thing, i have no idea what heads i would be running. ive always been an NA guy so this world of boost is all new to me. i guess id throw on sme L92 or afr 225s?? i really dont know. do u have an idea what a good set of heads are for a motor like that?
Stock L92's and AFR's are on different ends of the map as far as heads go.
L92's flow air but they have a thin deck and tend to lift when trying to throw alot of boost at them and when trying to get aggressive on the tune. AFR's flow a ton and have thick deck for boost but the price of them is double that of and L92. If you want a good flowing thick deck stock head it would have to be the LSA head. The aftermarket heads would be AFR, TFS, MAST, PRC, and All-Pro. The one thing about All-Pro, you are going to pay $$$$ but they are the only ones I know of with a 1 inch thick deck on some of their heads.
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An aluminum block can handle 20-22 lbs Its not that much of an issue. You will lift the heads before the block gives you any problems. Mark Koehler of the Ohio Boys ran a stock LS2 block one year to 35 psi before the stock cylinder liner cracked and he ran 7.99 like that.
Stock L92's and AFR's are on different ends of the map as far as heads go.
L92's flow air but they have a thin deck and tend to lift when trying to throw alot of boost at them and when trying to get aggressive on the tune. AFR's flow a ton and have thick deck for boost but the price of them is double that of and L92. If you want a good flowing thick deck stock head it would have to be the LSA head. The aftermarket heads would be AFR, TFS, MAST, PRC, and All-Pro. The one thing about All-Pro, you are going to pay $$$$ but they are the only ones I know of with a 1 inch thick deck on some of their heads.
Stock L92's and AFR's are on different ends of the map as far as heads go.
L92's flow air but they have a thin deck and tend to lift when trying to throw alot of boost at them and when trying to get aggressive on the tune. AFR's flow a ton and have thick deck for boost but the price of them is double that of and L92. If you want a good flowing thick deck stock head it would have to be the LSA head. The aftermarket heads would be AFR, TFS, MAST, PRC, and All-Pro. The one thing about All-Pro, you are going to pay $$$$ but they are the only ones I know of with a 1 inch thick deck on some of their heads.
i wonder if i could have extra holes drilled in the block to accept the 6 bolt heads? do you guys think i could get away with 18-20 PSI on the LQ4/9 or on the aluminum block? id rather put boost to an aluminum block 402 instead of a 408 if i coud still reach my goals
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thanks to everyone for all the info. i know alot more about boosting a motor thanks to you guys.
i wonder if i could have extra holes drilled in the block to accept the 6 bolt heads? do you guys think i could get away with 18-20 PSI on the LQ4/9 or on the aluminum block? id rather put boost to an aluminum block 402 instead of a 408 if i coud still reach my goals
i wonder if i could have extra holes drilled in the block to accept the 6 bolt heads? do you guys think i could get away with 18-20 PSI on the LQ4/9 or on the aluminum block? id rather put boost to an aluminum block 402 instead of a 408 if i coud still reach my goals
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You can't just drill the holes. Material would have to added to the block to make it a 6 bolt setup. ERL does it to stock blocks all the time. I would do an aluminum ls2 block as a 385 setup from AES. It would get you a better piston in the bore and trust me, you won't miss the 17 cubes under boost.
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Just want to give you an idea of price difference of the 6 bolt superdeck and an LSX block. You might find an LSX for around 2200 at the cheapest (that was awhile ago I looked at that so it might be more now)and an ERl superdeck is 3500.
The ERL block comes with ARP main studs and the LSX does not. That's a little over 300 bucks right there. The ERL block is hand honed on the deck surface and the LSX is not. Plus there will be alot more machining than just that on the LSX compared to the ERL. So, now the price gap is a little closer and one more thing, the LSX block is 140 lbs heavier than an ERL block. Reckless, a mod on here weighed all the GM blocks and the 6.0L truck blocks were 110 lbs heavier and the LSX was 140.
The ERL block comes with ARP main studs and the LSX does not. That's a little over 300 bucks right there. The ERL block is hand honed on the deck surface and the LSX is not. Plus there will be alot more machining than just that on the LSX compared to the ERL. So, now the price gap is a little closer and one more thing, the LSX block is 140 lbs heavier than an ERL block. Reckless, a mod on here weighed all the GM blocks and the 6.0L truck blocks were 110 lbs heavier and the LSX was 140.
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You can't just drill the holes. Material would have to added to the block to make it a 6 bolt setup. ERL does it to stock blocks all the time. I would do an aluminum ls2 block as a 385 setup from AES. It would get you a better piston in the bore and trust me, you won't miss the 17 cubes under boost.
IMO I'd prefer to keep nice thick bore walls for a more rigid block, and you simply dont need a 4" crank.
Plus with a shorter stroke, the piston doesnt drop out of the bore as much at BDC.
One of AES 3.825" cranks and an LS2 block would make plenty of power and be a strong affordable platform.
As for the 4 bolt argument. ARP make a much stronger head stud in standard M11 size. or you could go for 1/2" studs.
Both easier and cheaper than 6 bolts, and will be a good improvement over normal ARP studs
That's assuming you might have an issue with them in the first place. Many push very hard with regular ARP stuff and have very few problems.