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any tips on timing and tuning one of these old turds ?...had to pull the smog pump ...and umm where the hell can u put blow off valve?
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Re: 83 buick riviera t type
Do you really need a blowoff valve at 5 psi, with a draw through on an automatic? I tuned a 3.8 turbo quadrabog back in the 80's by replacing it with a 350... ran great after that. :-XOriginally posted by sureshot customs -
Re: 83 buick riviera t type
For starters, this thread shouldn't be in the "Bangshift Blog" section.
As for the early 3.8 Turbo:
1. A blowoff valve on a draw-through installation is both unnecessary (turbo spins in vacuum after the throttle) and muy-dangerous (air/fuel mixture floating around underhood)
2. Back in the day, these engines responded to:
a. increased boost with water-alcohol injection (e.g. C.J. Baker's "Sunday Driver" in HRM back in the early 1980s).
b. more cam timing (shoot for something ~ 215-220 degrees duration (at .050) . . . up to 230 degrees would be okay with more "gear" in the final drive).
c. The stock heads are restrictive and respond well to porting.
d. And as with all turbo cars, minimizing pre-and post- turbo restrictions pays dividends (e.g. Thunderbolt-style ram-air zip-tube with a low-restriction air filter; big post-turbine exhaust.
e. A small nitrous plate system will also work ok if you don't go nuts on the jetting. (To save a little on the nitrous bill, use a hobbs switch to shut it down at 1-3 psi boost, so nitrous only flows when you're trying to spool the turbo.)
3. If memory serves, the stock turbo is going to be "all in" by ~ 300 h.p., so you'll need to upgrade if you're going crazy (e.g. built long block, huge boost on race gas)
4. Big power builds will follow the well-worn Grand National path (EFI conversion, big turbo, big intercooler, etc) The GN folks have lots of info on this.
5. Before starting any mods, make sure the thing is running correctly (good compression, no vacuum leaks, new ignition cap, rotor, wires, plugs, rebuilt carb).
6. With FWD, a major problem is going to be hooking up to the track. That doesn't mean that you couldn't have a lot of fun with hopping it up.Comment
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Re: 83 buick riviera t type
I forgot to mention that camshaft lobe separation should be greater than 112 (wider is better unless you're running a turbine with a big a/r ratio and have low turbine inlet pressure, which can tolerate more overlap)Comment
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