Supercharged 7.3

[TyCorr]

I miss reading your posts regularly.

You have a way of explaining and wording things that make them crystal clear.

 

[superpsd]

I don't see how the turbo is going to come up faster than a positive displacement blower that is directly proportional to the engine speed vs load for the hairdryer. Some of these blower over turbo setups are seeing as high as 10 psi at idle. The commonly used is "snappy" and a snappy responsive engine is what I want. That's my goal as I have a 5 speed truck. I don't care what kind of turbo you have when you let up to shift the turbo always loses some inertia and must respool whereas the blower will be right with the engine. The blower does not care how much fuel you feed the engine it's going to push out the same pressure.

 

[2000wa250]

Snappy responsive engine....

Small exhaust housing, big oil....

Heat drives turbo. Period. Using exhaust gasses doesn't load engine. Blower does. More work to build pressure with blower unless you pulley it way down. Do that and you have no top end. Put charger before blower and blower is taking boost and compressing it further.

Sent from my SCH-I545 using Tapatalk

 

[TyCorr]

Snappy responsive engine....

Small exhaust housing, big oil....

Heat drives turbo. Period. Using exhaust gasses doesn't load engine. Blower does. More work to build pressure with blower unless you pulley it way down. Do that and you have no top end. Put charger before blower and blower is taking boost and compressing it further.

Sent from my SCH-I545 using Tapatalk

He's comparing apples to oranges, no doubt.

One is parasitic the other is synergistic. Its increasing efficiency by converting wasted energy into even more power.

Op, I dont understand how you are having trouble seeing where you cannot compare the two. Think about how much rpm it takes to get each system moving and PRODUCING. The turbo produces easily what that blower wishes it could. In your method of comparing boost as read on a gauge.

We are going in circles here. Put it together and let us know. But measure the output as "it feels really good" is not a measurable result.

 

[2000wa250]

Bud, obviously you are dead set on doing this, were just trying to help so that when you do get it all figured out you haven't wasted a bunch of time and money on something that ends up being a pita to deal with.

We haven't even talked about tuning yet....which BTW will probably be a nightmare to get dialed in with the blower in front of the turbo. Not because of the blower, but because things are going to get really in efficient really fast. That blower simply is not going to be within its efficient pressure map being used as a secondary....

You want throttle response with little to no smoke? Get yourself a set of hybrids and have them detuned for the stock turbo. Most likely won't need oil mods or fuel mods, will have the throttle response you want, and as long as the tuning is dialed should be relatively smoke free. Not to mention it will run 100x cooler than a blower being ran constantly right at its recommended limits, and a turbo that is struggling to get air because it has two giant screws blocking the free flow of air.

You talk about putting a bypass between the blower and turbo...if I understand this correctly you want to have a way of feeding air directly to the turbo? So in other words giving any miniscule boost the blower has or can build a place to exit?

****, if all you're after is faster feeling throttle response, and more usable boost (which remember is a function of restriction, so more doesn't necessarily equate to better) then why don't you throw a set of 4.10's in it and let her tach out!?

Have at it, and do what you will, but I am telling you, not to mention two of the most knowledgeable guys when it comes to 7.3 engines, both tuning and mechanical, HRT and charles, that you are not going to get what you are looking for the way you are planning to do it. Like I said already...hope you have an egt gauge pre turbo so you can do your best not to melt your pistons when that blower is trying to keep up and is feeding extremely hot air to the turbo.

Oh and good luck to the tuner that is going to responsible for tuning this monstrosity and trying to work around a blower.

Smh I still don't get why people think that boost = power... that only holds true if fuel and cfms are there without pushing the pressure ratios so god damn high that metal wants to run and hide. For example, I'm running a 468 with enough fuel for close to 600+... max boost I see? 35psi last time I was on the dyno and she made 557 uncorrected.... that's to the wheels, with 3.73's, a row boat for a transmission, and 6 blown injector o rings... you're trying to push about the same amount of boost, yet you will not make the same power or have the same throttle response because a) you don't have the fuel and b) you will be pushing the blower and turbo so damn hard that all you'll really be doing is generating heat....

Anyways, I'm done trying to give advice. Apparently the laws of math and physics do not govern the area you are located in, so enjoy your set up and good luck getting it all installed. In for pics.

Oh and I have a project name for this... project unicorn

Sent from my SCH-I545 using Tapatalk

 

[superpsd]

Drove it around with the blower on after finishing the alternator relocation. Shredded the first belt waiting on the second to arrive at the parts store. Need to stock up on belts just in case. Walking around Lowe's collecting a few more parts for the build.

I really appreciate all the negative support but I will press on to finish this up. This is not the first time I built a custom one off setup. My first beater diesel truck was a 6.2 idi that I put parallel twins on. Since I got into playing with Detroit two strokes I have a few 4cyl units and a rare V8. I've also worked on other platforms like cat, Cummins, Mack...

 

[Charles]

I don't see how the turbo is going to come up faster than a positive displacement blower that is directly proportional to the engine speed vs load for the hairdryer. Some of these blower over turbo setups are seeing as high as 10 psi at idle. The commonly used is "snappy" and a snappy responsive engine is what I want. That's my goal as I have a 5 speed truck. I don't care what kind of turbo you have when you let up to shift the turbo always loses some inertia and must respool whereas the blower will be right with the engine. The blower does not care how much fuel you feed the engine it's going to push out the same pressure.

The blower can only come up as fast as the crankshaft. A turbo setup can make full boost very soon. My Regular cab would hit regulated boost of 70psi as low as 1700rpm. And still be perfectly efficient at 3000+rpm. My truck gains boost for a second on a shift...

On the other hand a blower must lose boost on a shift, because as you said... it's directly tied to the crank, which slows down! No wastegate to shut and bring turbine speed up, nothing.... just a slower spinning blower, making less boost off the shift, over and over.

Point being, a turbo is more efficient and will make boost faster than you want it anyway. Which is why I don't see Cat, Cummins, Deere, International, Yanmar, Mack or any other company of that level running blowers and turbos.

You can have snappy and responsive with no forced induction at all. Just run a nice set of nozzles and bring ICP in quick.


If you're going to do something that makes little sense, I would suggest doing it before talking about it if you don't like to hear the responses.

Sounds like you've got it about done. Lets focus on that.

 

[superpsd]

Well got my new belt and found the issue. I had lined the alternator up the best i could but it didn't like the alignment. It was pulling the belt over the lip of the PS pump pulley. Luckily I had two ribs still hanging on to make it over to Autozone. Installed the new belt and realigned the alternator in their parking lot. The belt is now happy and I drove around town with no other issuez. I did find what I have been looking for. Still had been struggling with how I wanted to build the blower discharge as there is only 2" clearance between the 4" discharge hole on the bottom of the mounting plate and the valve cover. I bought a 1" thick 4x4" Carb spacer that is perfect with a little milling and welding. Need to get the bottle filled Monday and start mounting the Intercooler. Just waiting on my silicone couplers to arrive and need to order smaller blower pulleys.

Quicky video
http://www.youtube.com/watch?v=WVo3BlIQNMw

 

[TyCorr]

It runs. What else were we seeing there?

Why didnt you floorboard it?

 

[superpsd]

Blower was just free spinning. I was just making sure the belt worked. After realigning the alternator the belt is happy. There is less wrap on the AC compressor but it's still enough to blow ice cold. If it becomes and issue I will add an idler to increase wrap but so far it dosent seem to be a problem. Just need to finish building the discharge elbow for the charger and mount the 6.0 intercooler. After the intercooler is installed I will drive it to the local header shop to bend some tubing for the charge pipes.

 

[Charles]

Blower was just free spinning. I was just making sure the belt worked. After realigning the alternator the belt is happy. There is less wrap on the AC compressor but it's still enough to blow ice cold. If it becomes and issue I will add an idler to increase wrap but so far it dosent seem to be a problem. Just need to finish building the discharge elbow for the charger and mount the 6.0 intercooler. After the intercooler is installed I will drive it to the local header shop to bend some tubing for the charge pipes.

Just get some donuts and a straight stick in whatever size you plan to use. It will be much simpler, look nicer and flow better. Muffler shop benders are crap compared to a donut.

If your header shop has a mandrel bender then I don't know what you've done to the owner to have him tie it up on something like that. There would be a lot of waste on a mandrel machine anyway.

Donuts and straight sticks, one afternoon and done. I hope that thing quiets down some when hooked up... sounds like the crappy point when the fan clutch locks up every now and then and you just have to deal with it until it goes away again. Hopefully it doesn't stay that obnoxious all the time. Another problem with a crank driven unit.... it doesn't know when to stfu because you're just cruising.

I remember a cobra with an obnoxious blower making noise from hell one time. It was super annoying at full power as I pulled past until my rear bumper was out in front of his front bumper and the racket finally drowned out behind me.

He thought his blower motor was da bomb... Traction was my only issue off the start. His too. So go figure, the blower was no good down low and got walked up top.

Other than Mad max and the last of the V8's, I've got no love for blowers. When he layed it down on a 1000cc bike that thought he was the sh*t that did plant a seed in my head though. Outrunning a streetbike with a car.... almost as fun as outrunning a sports car with a lifted diesel....

But seriously, get you some donuts and a straight stick and rock out, Tig or Mig. Done.

Is a superduty CAC tube setup not even close enough to start with?

 

[superpsd]

Well I don't mind the noise but it could get annoying. If so I will ditch the cone filter and build an enclosed airbox. Some length of pipe between the inlet on filter should also help to a small degree.

 

[backwoodsboy]

If you ever find your way North to the Bellingham area I'd like to check this thing out in person.

 

[superpsd]

I have never been that far north on this side of the mountains but if I do I'll let you know. Today I removed the blower after a few test drives to continue building the discharge plenum. Still had been struggling until I came across a timing chain cover that fits and clears perfectly.

 

[superpsd]

So I had calculated the blower drive ratio before hand. I got a 2.33:1 drive ratio on the blower which put it at roughly 8000 rpm @ 3500. I am not seeing boost at idle. I am seeing 4 psi at 2000rpm. The blower is much quieter with all the plumbing hooked up. It will likely get louder once I pulley it to increase blower speed. The maximum recommended speed is 14000 so I have a lot of room to overdrive the blower. I will tinker with it tommorrow.

 

[superpsd]

 

[backwoodsboy]

4psi between stages, or 4psi total??
If the first option, what is your overall boost?

 

[superpsd]

That was in neutral. I only took it around the block once in the stock tune. I will be playing with it tommorroe. Will need to order a 2.5 pulley. You can even go smaller than a 2.5 but milling of the snout is required at a high cost. That would be pointless as I plan on a whipple 2.9 upgrade.

 

[Charles]

Be aware that even if you make more boost in neutral that may still go to vacuum as you go under load and the turbo tries to inhale the blower. If it's 4psi in neutral I'm sure it sucked your vacuum gauge hard when you stabbed it the first time.

Fwiw.... even at only 4psi, that would still be worth 4psi if the blower was after the turbo.

 

[TyCorr]

Be aware that even if you make more boost in neutral that may still go to vacuum as you go under load and the turbo tries to inhale the blower. If it's 4psi in neutral I'm sure it sucked your vacuum gauge hard when you stabbed it the first time.

Fwiw.... even at only 4psi, that would still be worth 4psi if the blower was after the turbo.

Ha ha...persistent.