Guess it's not just for oil sheiks anymore:

http://www.autospeed.com/cms/A_1447/article.html

 

First off, I LIKE WHAT YOUR DOING.
I have a simple question though, Why Turbo and then blower?
What is your basic reasoning or what is your planned benefit by stacking them rather than just going with the 35lb turbo?
Keep Up Good work,
Montana

 

Hey 32Krazy,
I have to disagree with you on the rear end failing under that kind of horse power, but time will tell.
I know you said you know very little about turbos but I have to say that it might be a little hard to keep paint on the fender in that small of area. Have you ever seen a turbo glowing red with the lights off?

 

Wow, you did it!
Congrats!
Hopefully you can get the fuel system up to par and get it tuned.
Man I miss that car.

Got a new toy though, not as luxurious but it will hang with most SRT's. The best part is the look on peoples faces when they get out launched by a fwd.

 

Don't quote me, but I believe it's to help illiminate the turbo lag, since your supercharger is always on.

 

In theory this is quite true. With the turbo probably not spooling until 3k RPMs in first gear, you would see the S/C boost from a dig with the turbo boost building as the RPMs increase. Since the turbo builds boost on a mostly linear plane as the RPMs increase, I would bet that he would only realize roughly a 18 or 19psi boost average across all RPMS, but then would be able to spike 28psi once the turbo is fully spooled.

The only other major issue I can see is the ECU throwing some major overboost codes once you hit about about 22-23 psi combined between the two...Though I'm not completely sure if codes would happen since only 14psi would be pushed from the S/C and thus the crank and the other 14psi would be pushed by the turbo, spooled up from the exhuast gases.

 

While I realize if the builder would answer this for us, people could quit speculating his intent but why wouldn't he be running pullies to get his boost from the S/C MUCH higher than the 14lbs you speak of ?

 

that about sums it up....

 

got to start out small and work my way up.. this is just the start.. if i can get it tuned correctly and everythang works out right i can start adding to.. if i go to high to fast ill prob brake something. I had a 178 pulley on it and was making up to 18psi not sure what will happen once i get up to 28psi .. if i wold have cep it and got up to 32psi stacked not sure what all i would need to do to the car.. but there is always more that can be dun

 

As someone who completely worked a 1986 Dodge omni GLH turbo with every mopar performance part available maybe I can offer some help. My car was running about 20 lbs of boost for the 1st 3 seconds then backed down to 15lbs.

I'd have to say make certain that the injectors are high flow & aren't leaned out at those high boosts. Also make sure the waste gate is operating properly.

 

I think the idea is to get high boost levels without spinning the hell out of the SC. You can only spin the SC so fast before it starts pushing super hot air and sucking up tons of power from the crank. Also by going this route he doesn't have to remove the SC and fabricate manifolds and such like with a turbo only setup. Way cool!

 

Interesting stuff..

Do you have a dataloger or any gauges?

 

It's great to see someone actually trying this. I've thought about doing it, but don't have the money right now. Hopefully Eric, you can get this working!

Question for you, though. You mentioned that the car is running a bit sluggish. Could it be from the turbo surging? The reason I ask is, if you are feeding the supercharger from the turbo, do you have any sort of bypass for the air before the turbo spools up? It might not be providing enough air to the supercharger at lower RPMs.

EDIT: Never mind. Surge is not the right word for what I was thinking.

 

Someone correct me if I am wrong but I believe turbo surge is when the turbo is creating more airflow than the engine can take in. If anything the supercharger might be starving for air, but I wouldn't suspect that either

 

Yep, you're right. I was thinking about compressor maps and the surge line is on the left, so I was thinking it meant it was not flowing enough air. Surge is when there is too much pressure on the output of the turbo, forcing air back into it. My bad for mis-thinking I'll go back and edit my post.

So surge isn't the right word, but is the concept correct? In that, there might not be enough air flowing into the supercharger?

 

you are correct. I see no problem with the setup. In the diesel world we are using large turbos that we could not normally run as a single and compounded with another smaller turbo would be laggy. we have started using superchargers to add drive pressure at idle and are able to make huge power increases far down on the powerband.

This is a proven setup and i expect to see good results once tunning is complete, as for the amount of boost, me personally i would run 8-12psi from the turbo, this compounded setup should see high 400's to the ground with enough fuel.

 

This is nothing new guys.
Compound Boost 2003 Mustang Cobra Twin-Turbo - Muscle Mustangs & Fast Fords Magazine

I wanted to do it when the car was mine but I didn't have the money and the tuning capability was not there.
I think that is gonna be your biggest problem. The factory fuel system will not support more than 400hp. You will probally need some sort of piggy back and larger injectors, unless there is something better out now?

You could possibly have the stock crank pulley machined down a bit to reduce your boost on the SC/ decrease parasitic loss and let the turbo do most of the work.
Another idea I had was to put a window switch on the supercharger clutch so it cuts out once the turbo spools. It might have to work a little harder to push air past the idle fins of the charger, but if the car can do it NA while cruising from the factory I'm sure some pressurized are can do the same.
Good luck!

 

6 diffs toasted this yr on cars running 350 rwhp and dr's. why would you think this kind of power (500 to 600) wouldnt kill the already weak diff?

eric i didnt know it was rear mounted!! whats your take on 2 smaller turbos with a full needswings dual exhaust? better or no?

 

from what i understand most ppl that use twin turbo setup is to reduce the lag that might come from just one large turbo. with the twin-charged setup the supercharger takes the place of on of the small turbos and gets you off the line faster without lag then the large turbo gives you a larger range of boost control on the high end. and also I have no idea where i would put another turbo. the one i have is where the resonator was and I barley have room for that one and all the oil pump/adjustable boost controller/ hose's/ wires .. its a mess hehe

 

this is the stuff i have for the fuel upgrades.. once i get this compleated i might move up to larger injectors if need be

Zeitronix Zt-2 Wideband Controller and- zt-2 Zeitronix USB to Serial Adaptor Cable -zt2usb http://www.needswings.com/Mann-Merce...01.aspxhttp://
Walbro 255lph In-Line Fuel Pump + SRT6 Install Kit
NeedsWings SRT6 Adjustable Fuel Pressure Regulator
Zeitronix Boost Sensor Add-on
Zeitronix Fuel/Oil Pressure Sensor Add-On
Fuel pressure Gauge Fittings
Zeitronix Relay