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Discussion starter · #362 ·
Heres how my turbos are going to be setup.


Using a ISF 3.8 exhaust manifold





I'm going to need to change the back of the AC compressor to get more room. I think it will work with a differ head.

 
I really like that manifold, but it looks right up against the AC compressor.
 
Pain in the butt to get too. Had to hound Cummins for a few weeks to get it. I guess is there isn't ISF 3.8 engines in the US so why would someone need it. But I don't know, every time they put in my order it got cancelled.

Anyways its like $67 from Cummins.
Will that manifold fit the older 4bt's? If so what PN am I looking for?
 
Darn, I'm surprised Cummins has any exhaust manifold that costs $67. Dieseldude, you could use it but you'd need to reshape the ports. ISBe ports are round and standard 4bt's are rectangular. Same deal as putting a common rail manifold on a 12 valve 6bt. Steed, even with moving the compressor ports to the side that looks to be a tight fit. You might have been better with this manifold which is off a QSB.
 

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Discussion starter · #369 ·
Yeah I was looking at that manifold. I need to change my compressor back head which will give me an inch or so then I think it will fit. I want to try to keep every low as possible.
 
Yeah I was looking at that manifold. I need to change my compressor back head which will give me an inch or so then I think it will fit. I want to try to keep every low as possible.
Have you thought about making a spacer to clear the ac compressor?

-vr4oaks
 
Looks like the real challenge would be getting the pipe from the low pressure turbo out to the intake on the small one. With the tightest radius 3" pipe, you're probably looking at 4 1/2" overall. If you had used the Ford Cummins ac mount it would probably been easier. Although the alternator would have been in the high position, they are thinner than ac compressors. Here's a photo.
 

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Discussion starter · #372 ·
I'm still up in the air on how I'm going to connect everything. The new AC head will give me more clearance and I'm debating on still using a supercharger for a three stage compressor. If I do I'll head a different compressor housing for the HE300VG.
 
Discussion starter · #374 ·
Yeah its going to be unique if I can get it all to work. Im surprised my supercharger hasn't exploded or made any crazy noise's as it is. I can peg my 35PSI gauge on the back of the 0 and I'm not even to 3/4 throttle.

I think with a 3 stage compressor, there would be even less strain on the supercharger then my current setup.

My idea is the supercharger is going to compress the output of the HE300VG, then feed into the HE221W. This will make sure the HE300VG isn't restricted by the supercharger, and since the HE221W will light stupid fast. It should create a pressure ratio drop on the supercharger output. Which intern would put less strain on the rotors. I might be wrong as all hell, but its just a thought. I might have upwards of 80 psi of boost with 30-40psi of drive pressure once its done.

But as of right now I get between 20-22 MPG sometimes 18 if I drive around like a A-Hole and blow a ton of smoke. But my truck drives considerably better then it did with the Supercharger Toyota 5VZ engine.
 
As I have read in the past, most guys seem to have the supercharger feeding the Turbo then the engine, as I read your post, you are doing the Turbo>SC>Turbo>engine? What is the flow rate of the SC VS flow rate of the HE300VG? This is on a 4BT or 4BD1T? Im sure the SC you got will feed enough for a HX35W, or even a HX40, but Im not 100% on the air that he300vg can move. I even had a thought of putting a SC on my engine but a mustang SC will only do about 10lb of air at full tilt, which will probably feed a HX35W fine but wont make enough boost to clean burn till it lights, and Im not feeling okay with dropping 2K on a new 35PSI SC unit. (Side question, what MAX boost have you seen with that SC alone?)
 
Discussion starter · #377 ·
The supercharger I'm using right now is a M122 off a mustang which will flow around 800cfm. Regardless of the supercharger you use, you still need to get it up to RPM to max out the CFM.

That's why Crazy Carl has the supercharger feed the Turbo then use a by pass valve once the Turbo lights. The Turbo will light alot faster and out flow the supercharger. Because you're engine cant max out the CFM of the supercharger at low RPMs.

Another issue with superchargers is rotor flex. However because I under spin my supercharger I don't see that being an issue.
 
The supercharger I'm using right now is a M122 off a mustang which will flow around 800cfm. Regardless of the supercharger you use, you still need to get it up to RPM to max out the CFM.

That's why Crazy Carl has the supercharger feed the Turbo then use a by pass valve once the Turbo lights. The Turbo will light alot faster and out flow the supercharger. Because you're engine cant max out the CFM of the supercharger at low RPMs.

Another issue with superchargers is rotor flex. However because I under spin my supercharger I don't see that being an issue.
I thought you had yours spinning by a smaller pulley? Thought it was overdrivenn, hmm, they suggested running s much larger SC then needed so you could move a lot of air down low, example is running a c-2 procharger, then a hx35 it moves 1200 cfm
 
Discussion starter · #379 ·
I had a 2.6 pulley on it but then I went back to the stock 3" pulley. With the turbo feeding the supercharger there's no need for a smaller pulley.

C-2 procharger may flow 1200CFM but at what RPM will it flow 1200CFM? If your calculating 1200 CRM with 10,000 engine RPMs, then you would only get 480 CFM with a 4,000 RPM governor on a 4BT. With the turbocharger feeding the supercharger you don't need to worry about the CFM of the supercharger. You only need to look at the compression ratio of the charger.
 
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