I just wanted to see the size(worst case scenario). If i a single 76 could do the job, i will just stay single turbo. Maybe put an 88 on there just to be safe

edit: the mpt70 has served me well so far. maybe i should use two of them on the next build.

i cant decide

 

two of them with the .96 a/rs will take forever to spool on a 350/355.

I know of a guy running two with .81 A/R housings on a 427 or 434 (dont remember) SBC, and hes running 10s in a full weight station wagon making damned good power. Spool time on a small motor is going to SUCK though

 

Engineermike is probably right about a single 76mm, but that turbo will be at its limits. IMO, get a bigger turbo which won't work as hard. An 88mm turbo is a good idea, but a T6 version is even better.

A couple of MP T70's with .68 housings should be nice too. So many options...

 

IMO the .68s would be just about right for a drag car. probably have boost about 3400 or so, maybe alittle over on a 383.

However, i would get a s488 and call it good. 88mm t6.....not really gonna go wrong there

 

The engine will be no smaller then 427(LSx block), i want a 4.125 bore for the heads it will be running. I was thinking a pair of MP T70's on the .68 housing, the idea of using two $500 turbos on a 7k dollar short block with 2k into the heads just seems wrong to me Likewise an 88mm on a T6 flange seems like it would fit the bill aswell. I guess i will have to get the engine in the car and start mocking up somethings before i decide.

But as long as we have the discussion going........ will twins spool faster and have the same top end compared to the comperable single large turbo?

 

I agree that a 76 will be at its limits in the high 8's, but felt obligated to point that out when folks were talking 106 mm turbo's with 5" exhaust, which is completely unnecessary.

The ST80 and PT4788 are both physically small T4 turbo's that are easy to fit, and will both run deep 8's.

 

go to theturboforums.com and talk to this guy
http://www.theturboforums.com/smf/in...?topic=80422.0

i guess its a BBC, not a SBC, but its a 427 i believe. 10.0's in a full weight wagon with twin t70s. hes making 800+ at the wheels IIRC. or check on here, about a month ago i posted a link to a pt88 corvette dyno, 982 at the wheels which would definately get you to your goals