408 tc78 build question
408 tc78 build question I have a new 6.0 iron block untouched, callies crank, callies rods, and wiseco -3cc pistons. I was going to do a 408 with Ls3 heads that I have, but now I want to do a turbo build because I don't feel like doing this all over again when I want more power. Now my problem is that my compression will be way too high with these pistons and ls3 chambers for boost. Ill have all arp hardware with whatever way I decide to go. So my question is what pistons should I go with for a 4.03 bore/4" stroke with these ls3 heads. I have trouble figuring out compression ratio and I would also rather not get rid of these heads if I don't have to (yes I know I have them for sale, if someone wants them ill still sell them). They are untouched so stock chamber size. Im looking into the 700rwhp range with a 6 speed.
Edit: NVM I see you are wanting to get new pistons.
i don't know how to calculate it there are calculators online to plug all your specs into. I'd shoot for around 9.1:1.
Only problem I see is that TC78 being WAY to small for a 408. You need at least a PT88 or a little bigger, a PT78GTS would sneak by, but not past 15-16 psi.
i don't know how to calculate it there are calculators online to plug all your specs into. I'd shoot for around 9.1:1.
Only problem I see is that TC78 being WAY to small for a 408. You need at least a PT88 or a little bigger, a PT78GTS would sneak by, but not past 15-16 psi.
Would it be alright if I stepped up to like a 1.15 ar or 1.32 housing I forgot to mention that. Found these pistons too, probably what Ill need to keep my ls3 heads. Diamond pistons 11576. Also what the hell does -28 cc mean? Does it mean -28 cc of compression or -28 cc from a flat top piston?
TC 78 is too small for that size engine. -28 CC is a dished piston. I have a 402ci lq9 with l92 heads 72 CC chamber and my compression is right around 9.3 with a 21cc dish. I'm also running a pt88 Turbo with a 1.08 a/r housing.
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i too am building the same motor and considering this turbo. unsure of why it is to small as i am not looking for huge horsepower. i have the callies 4.00 crank with rods and i went with diamond -28 ibf pistons and my compression is around 8.5
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408 with a tc is going to destroy your engine. Backpressure will be through the roof causing your exhaust temp to be at dangerous levels. A pt88 would work great with a 408, if your looking for quick spool. If you can fit a T6 S480 that would work best.
It's not about wanting to only make a certain amount of power and matching that with a smaller turbo to get more spool. Your EGT's will be through the roof, you will blow header gaskets, or seals on the turbo if and when you decide to push it.
yes it will work, but you will mark my words be changing it down the road.
A better option would be a turbo from Work turbo's with a 83mm comp side and a 87mm turbine or 93mm turbine side with a 1.10 housing.
yes it will work, but you will mark my words be changing it down the road.
A better option would be a turbo from Work turbo's with a 83mm comp side and a 87mm turbine or 93mm turbine side with a 1.10 housing.
Or the $899 S480 from Forced Inductions with the big turbine wheel and T6 housing would probably be ok. They are about the most reasonably priced bigish turbo I could find. In the end I decided to just go twins.