Johnv

Hi all,

About to start building a single turbo manifold for a 346 ls1, what size primary pipes should we go for, want it to spool up pretty quick and have potential for 600hp plus at wheels.
Looking at using MP T70 or MP GT45.

cheers
John

99Zcamaro

iTrader: (1)

im gonna use 2 1/2 with a T76 on 6#

Johnv

Damn thats huge

I was thinking 1 3/4 or 1 7/8 pimarys from ports to twin 2 1/2 merging into T4 flange

dacajun

iTrader: (19)

John,

I'm building a max effort 346 with a 95mm single and will be using 1 7/8 primaries. I see some using smaller, but I feel the 1 7/8 to be the way to go.

-Dave

Ping King

iTrader: (20)

i used 1 3/4 because i had planned on upping to a 408 in teh future. If youre sticking with a t70 id go with 1 5/8's to keep the exhaust velocity up.

Johnv

Will a T70 get me to 600 rwhp ?

so 1 5/8 = higher velocity and quicker spool up, but would maybe limit top end flow ?

ddnspider

iTrader: (26)

1.625 here

RealQuick

iTrader: (14)

You are talking log diameter righ? The thread starter is talking about the primary tubes that come off the head to dump into the log.

1 5/8 is doable, but a T70 is small so I would think you wouldnt need small tubes to help it spool. You can use 1 3/4.

Johnv

Considering useing T70 for street and GT45 for strip on same manifold,
so maybe the 1 3/4 primaries would be the go

Boostaholic

iTrader: (4)

1 3/4 twin t70s