mild 8lb boosted 400 cam reccomendation

[mopardart72]

i am going to be building a 400 big block stock internals and the big 3 upgrades with a 70 trim turbo on 8-10lbs of boost

so what im trying to figure out is. whats my best lift/duration cam choice. want a streetable car, yet lopey idle

 

[txstang84]

Mad Dart ought to be able to help point you in the right direction, but I think he spends most of his time in the SB tech area, or forced induction section. In either case, I'd suggest you call up a custom cam grinder and solicit some opinions from those who routinely run turbos. A 400 ci engine shouldn't have much trouble building exhaust pressure for a correctly sized turbine, but the cam will have a great deal to do with that. I think what you want to avoid though, is too much overlap...too much overlap allows exhaust pressure to bleed at lower rpms and that hurts your spool time. Have you checked out the turbo forums yet?? There are some pretty bright guys in there.

turboforums.com

Also check out forcedinductions.com...call them and speak to a fella named Jose, if he's still there.

I might be stating things you already know, but if you don't buy a correctly spec'd turbo, you'll have something that could either spool up fast and dies quickly on the top end, or takes forever to spool but exceeds your max engine speed efficiency. I'm going to guess by 70 trim you mean a 70mm impeller, but have you figured out what size turbine and A/R housing you want to run?

 

[txstang84]

I just noticed your other post here, just down a couple threads. Are you seriously looking into putting in a turbo, or just looking at options? If you're asking what headers to use with a BB in an A body then within barely 12 hours, switch to what cam would be good for a turbo build...?

I'm sure there are dozens of folks who'd want to offer advice, but just to save yourself some grief, do you know what you want out of the car? What's your hp, or ET expectation? Running a turbo will add significant cost to any project-even if you go with a cheap one off eBay that'll likely die inside of a year. Turbos require a pretty good bit of fabrication, and unless you have friends with those skills, that kind of work usually isn't cheap. You're also going to be looking at cutting holes in places they don't normally belong to route intercooler piping. Then start looking at bigger fuel system parts, and beefing up your trans, brakes, and chassis/suspension. Even a mild 400 with a modest build with 8-10psi will likely make enough power to start bending stuff and running other parts beyond their normal capabilities...

Just food for thought.