346 to 408...what is needed?
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Teching In
Joined: Jun 2005
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From: Wixom, Michigan
346 to 408...what is needed? What parts would be needed to convert a 346 to a 408? What stock parts can remain and what would need to be changed? How much RWHP would a 408 get you N/A and what would be needed to gain as much RWHP out of it?
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Joined: Nov 2004
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From: Tuscaloosa, AL.
Lots of research, lots of cash, and lots of patient..............
However, dont get discouraged,
It is basically a new engine, w/ new everything (pistons crank ect...)
will cost you about 6-8k for the long block depending on internals and heads
will produce anywhere from 480-550 RWHP
supporting mods should include
clutch
rear end
Plus all bolt ons if you wish to maximize your power
I am not an expert by any means, but i do plan to go with that setup
My projected project costs are upward of 20K / nitrous kit, roll bar(not an option if you want to take it to the track).
Read up on it. If it intrests you call someone like TSP or futral(both sponsers ===>
They will hook you up. Dont get concerned w/ cam specs and whatnot. Figure out your goals and have one of those guys give you advice. I assume from your question, no offence intended, that you dont intend to do the work yourself. However if you do there are some good books out there< Chevy ls1/ls6 performance a well as How to build a performance ls1 engine > and there are also some websites that specialize in modification walkthroughs such as installuniversity.com.
The 408 is a great engine! Built right it can make 550RWHP NA, and support and power adder(nitrous, turbo, blower) that can make upwards of 800RWHP. Be smart, and do your research. good starter mods are lt headers, lid cat-back, IM, TB , SFCs, LCA's. most of these are pretty safe and the right combonation can get a fully bolted car to around 350, or maybe a little higher w/ a good tune. Have fun and enjoy your car!
However, dont get discouraged,
It is basically a new engine, w/ new everything (pistons crank ect...)
will cost you about 6-8k for the long block depending on internals and heads
will produce anywhere from 480-550 RWHP
supporting mods should include
clutch
rear end
Plus all bolt ons if you wish to maximize your power
I am not an expert by any means, but i do plan to go with that setup
My projected project costs are upward of 20K / nitrous kit, roll bar(not an option if you want to take it to the track).
Read up on it. If it intrests you call someone like TSP or futral(both sponsers ===>
They will hook you up. Dont get concerned w/ cam specs and whatnot. Figure out your goals and have one of those guys give you advice. I assume from your question, no offence intended, that you dont intend to do the work yourself. However if you do there are some good books out there< Chevy ls1/ls6 performance a well as How to build a performance ls1 engine > and there are also some websites that specialize in modification walkthroughs such as installuniversity.com.
The 408 is a great engine! Built right it can make 550RWHP NA, and support and power adder(nitrous, turbo, blower) that can make upwards of 800RWHP. Be smart, and do your research. good starter mods are lt headers, lid cat-back, IM, TB , SFCs, LCA's. most of these are pretty safe and the right combonation can get a fully bolted car to around 350, or maybe a little higher w/ a good tune. Have fun and enjoy your car!
Originally Posted by ramairstyle00
nothing is the same... its a 6.0 block bored out with a stroker crank
money makes cars go vvvaaaarrrrooooommmmm!
Youll need new block (iron or ls2), new crank, new pistons and rings, new rods, bearings, new heads and gaskets, a monsterous cam, and dont even think about running it on the stock tune 
Originally Posted by ramairstyle00
don't think you can use the ls2 block as its bored and the ls2 block is like the ls1 block..... a 402 would still be sweet though
This is correct. If you need those extra 6 cubic inches, youll need the iron block. I kinda use 402 and 408 interchangibly in my mind. Sorry.
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Originally Posted by GuitsBoy
Youll need new block (iron or ls2), new crank, new pistons and rings, new rods, bearings, new heads and gaskets, a monsterous cam, and dont even think about running it on the stock tune
Or even a base tune
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