I have always liked superchargers better than turbochargers because of how simple they were to make work, and because of the ease of adding boost (smaller pulley), and the low end torque, and the fact that we had more cars with superchargers than turbochargers so I just prefered them. Well today, I was messing with my car and realized a very good advantage of a turbocharger. Because the wastegate actuator is vacuum contolled, the more vacuum it has, the sooner the wastegate will open. Well, I was messing with my boost controller and I drilled a small hole (1/6") in the vacuum line that runs to the wastegate actuator and then took the car out for a drive. Theoretically this should not give the wastegate actuator as much vacuum, meaning it won't open as far, and the turbo will produce more boost. Knowing that the computer has a fuel cut-off when it detects too much boost, I wasn't worried about blowing the car up testing this, so I went out and tested it. So I pull out of the subdivision and get on the gas a little, and my boost gauge wasn't working (it cuts in and out, I think it has a loose connection or something) so I didn't know for sure if it was effective, but the car felt much quicker, and it didn't hit a fuel cut. So the boost gauge started working and i got on the gas and went WOT and the boost gauge read 4-5psi more boost (it read 7.5-8psi before, now it is reading 12-13psi), the car seems to have hella low end torque compared to before (it would only chirp the tires from a stop before, now it will chirp them from a 20mph roll), and it pulls like crazy in 1st, 2nd, and 3rd. It feels quicker than the other one we have, and that one has a chip in it, a less restrictive exhaust, a colder t-stat, and a less restrictive air intake. I was getting on the freeway to test out the topend, and while I was checking my blind spot when merging onto the freeway, I almost ran into a van because the car was accelerating much faster than I had anticipated. But while I was making these runs, I was pretty sure the intake hose had fallen off, because all I could hear the whole time was the turbo spooling. So I pulled off to the side of the road, and sure enough, it was still on. So I kept driving, but now the turbo sounds AWESOME, and when you let off the gas it sounds like it has a BOV. It is awesome. I have been trying to think of reasons to run to the store all night long just so I can drive it! As much as I love superchargers, I am beginning to love the turbocharger more because it sounds so awesome, and I added 4-5psi boost for free, whereas on a Supercharged car I would have to buy a $66 pulley, and usually a smaller belt or larger tensioner.

Now my dad is asking me to modify his boost controller for his because of the gains!

Shawn

That sounds great Shawn, sure is cheaper than a pulley swap. The bypass also controls the turbo'* top rpm does it not? I'm only thinking that you dont want the turbo to run away on you and the bearings let go? Do you know what the max rpm you can run the turbo at, just a thought?

You think you'll get a BOV, for quicker shifts? Turbo'* are neat, i've been looking at them a lot. I've got a Hot Rod magazine subscription, and the last issue had pt 2 of a 3 part series on Turbo everything. I know so much now, i could be dangerous!!! I'm thinking a T04 would be sweet on my L27.... I got the badge for it too!

Use a T04E 60 Series would do well on the 3.8L. Just a hint.

60 series? That'* about what i'd use if anything. Sounds right from what Hot Rod said as well. A T03/4 hybrid might work too. Not a T04 88mm inducer?

Oh yeah, the first page of that Hot Rod'* turbo stuff, a nice twin turbo'd 350...

I don't know what all the bypass controls. I also don't know what rpms the turbo is spinning at when it is making that much boost. I don't think it spins much quicker than the one on the other car with a chip, since the other car only makes ~1psi less boost and I think the chip does the same thing, it just drops the vacuum electronically instead of doing it by causing a vacuum leak. Maybe I am wrong though. The turbo seems to be in good shape, and I have been trying to do the proper warm up and cool down on it everytime I drive it to try to keep it alive longer. Since I know a turbo rebuild for that particular turbo is $550, I am trying to not have to do that anytime soon. I am probably going to clean out the oil & coolant lines that run to it to make sure it is getting adequate oil and cooling too.

Shawn

What do you do to warm up and cool down a turbo?

WOT=warm up..
idel=cool down..

i sure hope your kidding about the

WOT=warm up

your probably not....but thats a no no

idle=warm up

idle=cool down

WOT=in between