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I am going to do a compound turbo setup with my HX35 as the primary and an S400 on the bottom. My question is do I have enough fuel to light it? My sig has everything that is done to my pickup so far. Before the turbo goes on I will be doing studs, marine gasket, marine pistons for the injectors, 60lb valve springs, 4gsk, dvs, and a full feramic 13in valair clutch. Also how hot do you all think this setup will get? I have pinned my 1600 degree gauge the way it is now.

well if u can pin ur gauge then u should have the fuel to light turbos

it should light just as quick as it does now, you wont have much lag and hold on to your pants when it does:choochoo:

Also right now I'm making 320 horse and 700 torque what ball park will I be in with the turbos, dvs, and marine pistons?

I'd skip the Marine pistons honestly. Just time it a little more, and the fuel should stay in the piston bowl just fine. As for lighting the turbos that should be no problem with the amount of fuel you have. Which s400 are you putting under it? You will want a pretty big external wastegate as well to accommodate all of that fuel, You may also want to switch to a 14 or 16cm exhaust housing as well.
Sean

Well i was thinking the marine pistons because i'm getting a lot of blow by and i figured that i might as well do marine pistons. As far as timing how much should i go for? I'm going to tear the timing cover off soon because it's leaking a good bit of oil and since i'll be in there i was going to bump the timing. I'm not sure exactly what S400 it is but it has a 1.32 A/R and a 75mm compressor wheel. What should i gate it at? thanks for the help.

That would be an s475, and the 1.32 A/R is a good choice. The bigger you can go on the bottom housing the more you will minimize restriction and therefore you will keep better spool up.

How is your stock wastegate mounted? If the controller is mounted on the exhaust housing, you could run a 38mm external gate and run the internal gate a well. If the controller is mounted on the compressor housing, like my 24v is, then I would just weld the internal gate closed and run a 44mm gate for your application. Running a 44mm gate would give you about 6-7% more wastegate surface area than running the 38mm and the internal gate. However the price difference between a 38mm and 44mm is about $150.
Sean

I think it's on the exhaust side but im not 100% sure. what should i set the timing at if i bump it to much before studs will i blow a head gasket?

Have you had the killer dowel pin dealt with?If not you should get it taken care of while you got the timing cover off.

Without studs or O-rings, I wouldn't go much beyond 15.5-16*. We did that on my friend's 96 similarly set up to yours, and it made a huge difference in smoke and EGT's. But his was an auto with the smaller pump too.
Sean