Turbo build

[Jaredpear]

Okay so bare with me here. I have a k2500 with a mpfi 454 and I'm wanting to Turbo it. I've been really obsessed with a sequential setup where there's a small and a bug turbo and the small turbo turns off when the big turbo comes on. The whole engine will be getting rebuilt with forged internals and running on corn with a mega squirt ecu. I've already picked out the small turbo which is a borgwarner s400sx-e 72mm and I'm trying to pick out a big one, anyone have any ideas? Also, I'm trying to possible find a better way to control them. As of now I found some vacuum actuated exhaust cut outs that I'll be using with some boost controllers to control them. I plan on revving it from 6500-7000rpm with the first turbo steaming out at about 4500-5000 rpm at 17 pounds based on my calculations and the borg warner match bot

 

[skylark]

A 400 series borg warner is a substantial turbo on its own. A 475 will accommodate 800+ hp.

 

[Jaredpear]

The sx400sx-e I picked out is good for 1200, the horsepower isn't the concern, the sizing that I have picked out makes it start building boost at 1500 and finish at about 4500, which is why I want a bigger turbo, to accommodate the high rpm rev range.

 

[90halfton]

7000 rpm big block and 1200 hp. Umm. Awesome lol.

 

[Jaredpear]

Hehe I'm not actually shooting for 1200 hp that's just what the turbo is good for lol. I'm actually building it more towards torque with a goal of 800-1000 ft/lbs to the wheels

 

[Christian Steffen]

I don't have any useful turbo advice, but all i can say is I'm very interested to see how this goes. This will be a badass project.

 

[Tom P]

I don't have any useful turbo advice, but all i can say is I'm very interested to see how this goes. This will be a badass project.

Same here... Very interested in this build. I'll be following this with earnest. I would think Borg could tell you what size would match up?

 

[Christian Steffen]

What do you have planned for the transmission? What compression ratio are you going to run? I've spent some time cruising around theturboforums.com, turbo 454s can be mean as hell. haha

 

[Jaredpear]

I haven't gotten ahold of borg warner yet to see what they think but I should get to that soon, and for my transmission, either a built full manual valve body 4l80e or I'll swap the nv4500 into here. I haven't decided yet. And my goal cr is 9.5

 

[Jaredpear]

But does anyone have info on a good turbo for say 3500-7000 rpm for a BBC?