twins piping size?

[12VALVEADAM]

I am building up a set of twins 66 over s480, and was wondering what size the hot pipe between turbos should be 3" 3.5" 4'? i was leaning toward 4" just for flow, but will it hinder spoolup? Just cant find a good answer on this. Any help is great!

 

[OrangeNV]

i believe 4" pipe is larger than a t6 flange......so you would have to do some fancy fabrication

 

[gunracer1]

i use 3"

 

[12VALVEADAM]

oh ok thats good to know lol gunracer did you use all 3" for hot and cold piping?

 

[95smokin]

Mine is 3" as well.

 

[Texas Cowboy]

4" here.

 

[shiftycapone]

I used 3". Ht4c primary, 62/71 secondary.

 

[12VALVEADAM]

How does the 4in work cowboy?

 

[Lostnwalmart]

use 3" for the hot pipe it will flow plenty

 

[TRUBBS]

i believe 4" pipe is larger than a t6 flange......so you would have to do some fancy fabrication

I think you can get a "distorted" flange deal from columbia river that would be a close fit to a t6 foot.. Not 100% on that tho

 

[12VALVEADAM]

Ok sounds like 3" will work great, what about the charge pipes?

 

[Lostnwalmart]

4 inch if you can fit it 3 in will work also but I hear 4 in works better.

 

[12VALVEADAM]

Ok yeah the primary is going up on the fender/battery area so I have more then enough room

 

[12VALVEADAM]

oh and should i get just plain jane 3'' exhaust pipe or somthing special?

 

[Triple 7]

oh and should i get just plain jane 3'' exhaust pipe or somthing special?

Schedule 40 3" is what I use. Its really up to you what you want to use for charge piping.

 

[thojer81]

there is a thread awhile back I remember reading about guys discussing about 3 or 4 inch pipe. I believe the census was to use 3'' to keep the expansion of gases to a minimum and maintain better velocity.

 

[gunracer1]

I use 3" sec 4o for the hot side and 4" donuts for the tight piping on the cold side. I get the donuts from the chassis shop dot com.

 

[gwhammy]

Three inch with mandrel bends. A 180 bend makes getting out of the top turbo easy. 3 inch schedule 40 on the hot pipe although the one I'm building right now is 3 inch stainless schedule 10. I build a jig to use in a press to distort one end to a rectangle for the big turbo flange. Works pretty decent. On the schedule 40 I usually cut a three inch hole and then angle cut some slugs out of the plug piece and weld them back to make the transition better. There are some real nice transition flanges out there but I'm to cheap to buy them.

 

[12VALVEADAM]

ok cool so 3'' pipe it is umm gwhammy where could i find those flanges you were talking about? Anybody have a good idea for the mount over the fender?

 

[gunracer1]

I think source automotive has the transition pieces.