I belive its gonna be alot of work, but i wanna try it,
Mike how much Psi did u get with your twins? askin if would need to o-ring my head or would a cometic head gasket and a good set of studs do it?

 

Don't go with the Cometic, at least not for a while. A majority of trucks running cometic's have lost their head gasket in a relatively short time. Ratsun on here had a fully prepped block and head, and it still failed after a couple months. Personally, I'd run the marine gasket and O-rings. The Cometic gasket I have sitting in the basement will be on its way back whenever I get a chance.

 

The most I've every pulled is around 70 psi. I'm still using the same head gasket since I've put the o-ringed head on with. Looking at the picture is hard to see whats going on but is your primary turbo on top your exhaust manifold and then your secondary turbo? I'm no expert but I think that if that the case you might be a slow spooling set-up. Most set the secondary to get the exhaust first as it will start making boost easier than the primary.

Whats the air tube coming over top the engine from the driver side for? You welds look better than mine and looks like your one good fabricator. I'm scared to post a picture of my hot down tube, it looks scary but its was easy to build. I want to see how if it works/survives before its my final design. Right now my design will work for just about any turbo I want to put under my secondary, of course I just have to slightly rotate my down pipe elbow and adjust the primary turbo flange angle some.

 

Mike.. the pics are not from a 5.9... guessing its a Perkins... intake and exhaust are on the same side.. (right) exhaust manifold is just dropping the small turbo down.. Just looks a little different... Very nice work...
Bryan

 

That set is on my Perkins the Hx35 is of the manifold the HT60 had more clerance the way I have the air cleaner goes on the 60with out any extra pipeing.Hope I will be finding out how the run in a couple weeks.
Dale

 

thats a nice looking set of twins you got there. i didnt know a perkins would withstand twins. lol. if you are going to build twin turbos on a cummins, the first thing to do is flip the manifold upside down. the stock manifold will not allow a hx35 air snail to turn all the way down toward the intercooler like on most twin turbo setups you see. i just had the muffler shop build a pipe up and around everything. probly not the best, but it works.
you can buy an aftermarket manifold with more clearance on the manifold so you can have a short tube going to the intercooler.
i almost bought a set of cometic head gaskets, but after this im glad i didnt.
do you have to buy studs when o-ringing the head? those things are expensive! how much does it cost to just o-ring the head?
where is the best place to get o-ring head gaskets?

 

yeah im having the same question, where is a good place to o-ring the head somewhere not too far away from el paso, Tx and how much would it cost?

 

hey, i have a couple of specs for head o-ringing, how to do it and everything. i also asked a shop in our area, they said they could do it for me... so if i ever need to do that, ill try it.

 

It would be nice to have both one truck designated to building and plenty of cash for it. Heck, if I had that set up my wife and family just might kick me out. No fun there, no place to do the work. I would have to use my money and sell the truck for a new place. So no matter which way we look at it, one step at a time with the cash we can hide away. lol

 

Keep in mind that a small set of twins at 450hp will make as much boost as a large set at 700hp. Boost is an unfortunate byproduct not a goal. I like to keep things at around 65psi max, with 35psi out of the bottom charger.

 

^^ words of wisdom from the voice of experience.

With sufficiently large turbine housings and a larger compressor, 43psi will support 450hp at 2700rpm with EGT room to spare.

Then there are the example of guys running the poor stocker at 43psi and nearing meltdown EGTs at much less than 450hp.