Been making some changes to my old turbo kit so i thought id start a thread... I originally built this setup 4 years ago, i swapped in the 4l80e and 6l and added rod bolts, a mild cam, pushrods, and springs. I built the whole kit out of mild steel. It is an mpt70 with a 1.32 a/r twin scroll housing from a garret and an air/water intercooler. System worked great but i wanted to upgrade some things as the steel was rusting and i've since aquired a tig welder. Number 1 was to ditch the k+n as i was getting sick of finding dirt in my intake track and i wanted a cold air intake as well. I also installed a proflo xt manifold and 60lb injectors as the old 42's were maxed. I wanted to use a bellmouth on the turbo but could not fit a big enough paper filter so i built an airbox onto the turbo with a 5" pipe over to the main airbox behind the front bumper which holds 2 factory paper filters and gets nice fresh cold air from up front. im gonna run no intercooler and water inj for now to see how it effects response as i usually run lower boost anyways. I also plan on upping the downpipe and tailpipe to 4".

Old setup:


New setup so far:

 

Setup looks pretty clean, but I would reconsider running an intercooler. Even a cheap one will help out a lot.

 

thats pretty crazy looking. i myself have actually been thinking about trying to use stock filters. let us know how it works.

 

i do plan on running an intercooler again, just ran out of money... Plus ive always wanted to try it without to see the difference

 

Got it tuned pretty close today, Boost response is crazy fast! 1/3 throttle and it jumps to about 6psi around 2800 rpm. The intake makes it less jumpy on tip-in but the boost cuts in so quick it feels better when you lay into it. It keeps pulling harder and harder right till shift point though, makes me wish i had a forged bottom end so i could really let it rev! Highest IAT's i got was 68 deg Celsius on 8 psi with a run from 0-120 mph. I am having one problem though, it surges in between 1/4 and 3/4 throttle pretty bad. Im leaning toward BOV but im not sure yet. The BOV actually sounds normal now compared to fluttery on the old setup but it is hanging open at idle and the truck flutters at low throttle/high boost conditions....

 

try just adjusting the preload screw down a little bit. you want it to just close at idle. any more and it won't open on part throttle let off. too little and it will let off too easy.

 

i dont think mine has a preload adjustment, its a JGS, 60mm? i might try shimming it, its open 1/4" at idle...

 

thats what i love about mine. it has a preload setting and has a port for open and one for close. so it works of differential pressure vise vacuum.

 

which one do you have? i have a synapse on my sled and its very good but i dont think they would be big enough for the truck...

 

i have the raptor bov by turbonetics. i don't think i have ever had my turbo flutter. well it did when i first hooked it all up cause i did it wrong. but after i adjusted and hook the lines up correctly it works great. loud as hell though. like disconnecting an airline from a compressor.