putting a set of twins on my sig truck in a few weeks !

the top turbo is going to be HTT 62/71/13ss

the bottom is going to be either a s400 with a 80 =s480

or s400 with a 75 = s475

I dont want it to lag too much on the bottom end , but I like the idea of growing into the s480 which has unreal top end and is capable of well over 800 hp on #2 in a twin combo.

the standard s400 with a 75 is supposed to be good for low 700 hp on #2
the spool is supposed to be great , but of course the top end pull will be considerably less.

anybody know the drivability and actual differance in performance between these 2 turbos all Other things being equal ?
love to hear feedback from anybody that has taken a drive in a truck ,
with either or both of these this set-ups.

 

Nathan told me that the 62/13 on top of a s-400 80mm would be similar to the spool up of the 64/71/13

 

I run a 64/71/13 and a s480, mpi twins. I ran the 64 for a while as a single and the twins seem to light faster then the 64 did by itself. Its not exactly there lighting faster just moving so much air, feels almost like a stocker on mine. Id say go with the 480.

 

Can MPI make twins with a turbo a guy already has???? I was thinkin about doing twins but i dont want to bite the bullet on BD or ATS and have herd lots of good about MPI's. I have a II 6280 and i think that it would be a good top in towing twins. I do tow a bit with my truck and like the turbo alone, but it is out of its eficency range for what im pushing for power. Any info would be awsome. thanks

 

Yes! That's what Nathan just did for me. I just made sure to try to be very upfront with:

-what turbo I already had
-the configuration of the compressor and turbine outlets/flanges so that he can make the appropriate hot-pipe configuration as well as the correct offset on the pipes so things are perfectly square yet use the underhood space efficiently
-intended usage so that he can make recommendations based on his experience of what does or doesn't work.
-altitude I routinely drive at to ensure that I wouldn't have a laggy, smoke pig

He builds every set in his shop on his own personal truck to ensure things are correct!

 

nathan at mpi can do anything you need with twins including using your existing turbo!

 

cool hes gonna be gettin a call from me soon. thanks for the info