Lets talk TURBOS

[fabr]

Actually I think we're all in agreement.

[fastcorvairs]

I agree that is pretty impressive especially given when they were doing that. Any idea on the torque of the same motor? (Also the weight?)

Just for my curiosity I converted the 164CI and that's a 2700cc engine.

My 65 Corsa turbo coup two door tip the scales at 2775.  GM book say that the 180 HP was that @4400 RPM with 265 Feet pounds @3200. 

And I have a 3200 cc corvair on the engine stand in the shop now collecting dust.  Using VW pistons and Cly's.  With type 4 VW rods. 

[trojan]

I also thought that blowoffs help keep the impeller speed high so when you get back in it after backing off right away the impeller does not have to spin up so much.

Or is that what you meant by the minimising cavitation?

It does help keep it spinning a little (gear changes) but without enough exhaust flowing it spins down fairly quickly.

Cavitation is the wierd effect of a fluid in turbulance and it's very abrasive/damaging to the parts.

[fabr]

It does help keep it spinning a little (gear changes) but without enough exhaust flowing it spins down fairly quickly.

Cavitation is the wierd effect of a fluid in turbulance and it's very abrasive/damaging to the parts.

The opposite of that is surge that can break turbine or compressor  blades and such. Don't get me wrong I think using a BO valve is just good practice but not always/totally necessary.

[Enemy]

From what I gathered in my research, high boost spikes in a system slamming the throttle plates shut without a BOV can also make an impeller spin backwards. I believe there is a write-up on Garrett Turbos site.. Not to mention bent throttle plates.. Crazy shit huh!?

[Enemy]

Cavitation is the wierd effect of a fluid in turbulance and it's very abrasive/damaging to the parts.

I never believed that until I tore down a Stator/Pump assembly from a jetski with a cavitation problem a while back. The impeller looked as if it just came out of a blast cabinet, even had some material missing..All from water!?  DAMN... Open my , thats for sure.

[fabr]

I agree,HIGH boost being the key.

[Yoshi]

Talked to scott, he said anything under 10 psi is fine without an intercooler, and over 10 psi for short term runs.  He said i'll get my 300 hp (crank) no problem without one, and out of over 70 turbo busa rail motors he's personally built, only 5 had intercoolers......

[fabr]

I really cannot disagree with that BUT an intercooler is still a good idea since you cannot guarantee that the buyer will not run it for extended periods at full boost.

[Yoshi]

I really cannot disagree with that BUT an intercooler is still a good idea since you cannot guarantee that the buyer will not run it for extended periods at full boost.

He said it wouldn't hurt, which everyone will agree on, but said it's not necessary. He said the motor will be fine no matter what, just that it would run better at high hp for long periods of time with an intercooler.  I told the customer in the beginning the best thing to do is to build it to handle 400+hp, but run it at 300hp.  They just want to run the 400hp every now and then to race, I told them not to dune with it like that if they want the motor to last the longest.

Scott said he's gonna flash the computer/powercommander to retard the timing some more and put some limiters on the motor to make it as dummy proof as possible, I feel confident in what he recommends and what he says I do and do not need. He's built a ton of turbo busa rails and has a great reputation, plus he races turbo hayabusa's, so he's come up with a lot of cool stuff to make them reliable.

My motor builder said this is by far the best turbo kit he's ever installed.  He said it's the first time he every hooked one up and the motor cranked right over ran great the first time.........