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Old 03-13-2020, 07:09 PM   #101
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Seems like it should be a lot of fun.

I hope your employer take cares of you until the "social distancing" is over.
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Old 04-02-2020, 09:02 AM   #102
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Got one other idea. I think I figured out how I can get a bigger crank pulley to bring the boost on sooner.

Is there any reason that peak boost at say 6850 would NOT be better than 7200?

For example 22psi at 6850 and stop there vs 22psi at 7200. Again The higher rpm might make more power...
But not sure.
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Old 04-02-2020, 09:17 AM   #103
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Quote:
Originally Posted by Scuby04STi View Post
I highly doubt anyone has with much success, its large and not as efficient as a turbo.

My friend I race with runs one on his 5.0 V8 and my turbo 4 cylender makes more whp/wtq across the board
I've beat 88mm turbo 6L v8s with my little ej257 LoL and little 64mm turbo

Vortech makes good superchargers. If it's done right it'll do well I'm sure. Just need an intercooler and exhaust built properly. Same for turbo. And obviously tune.
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Old 04-02-2020, 09:50 AM   #104
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Quote:
Originally Posted by spoolinsti05 View Post
I've beat 88mm turbo 6L v8s with my little ej257 LoL and little 64mm turbo

Vortech makes good superchargers. If it's done right it'll do well I'm sure. Just need an intercooler and exhaust built properly. Same for turbo. And obviously tune.
Then that guy doesnt know how to set-up a car or drive it, lol. Seriously if you have 6L and an 88mm turbo and aren't tickling the 9's something is very wrong.

They do make a good product, its just a fact that they arent great at generating much for power under the curve as much as simply making peak power. Area under the curve is what makes a car fastest.

Op, typically im an rpm whore but in your specific case it might be worth the bump in boost across the board that helps the most seeing the engine is likely to be most efficient under 7k rather that over.
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Old 04-02-2020, 10:56 AM   #105
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Car made same power as mine around 650whp both street cars daily driven at time.

My car went 136mph on low boost with full exhaust wastegate opens at 20psi

When I turn the boost back up I'll pump my hood dump on and go back to track.
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Old 04-02-2020, 06:44 PM   #106
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Quote:
Originally Posted by spoolinsti05 View Post
Car made same power as mine around 650whp both street cars daily driven at time.

My car went 136mph on low boost with full exhaust wastegate opens at 20psi

When I turn the boost back up I'll pump my hood dump on and go back to track.
Prove it.
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Old 04-02-2020, 11:29 PM   #107
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Prove it.
What's your Instagram
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Old 04-03-2020, 02:02 AM   #108
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What's your Instagram
I don't do instagram. Post up here.
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Old 04-12-2020, 07:32 AM   #109
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Default Vortech supercharger for ~500whp? Si Too big?

Small updates

fluid damper ordered which will give me ~15 psi at 6300 and ~18.5 at 6900rpm. It (5.375Ē) is not as big as the ati (5.5Ē) but people here really seem to like the Fluid and for revving this out I want the improved smoothness of the Fluid.

I finally got my air intake out of the engjne bay and into the fender. Very psyched for 20-30F lower iat.

Also going with a new synapse BPV with 1.25Ē hose (intercooler is already welded for it so I figured why not).

And finally Iwire IAT relocation kit after the Air water intercooler so I can see just how much the SC is heating it up and how well the Air water IC is working.

For the future , I want to figure out what kind of short block to go with.

I think a ďstage 2Ē would do everything Iíd ever need to do. Ie stock case halves, forged pistons and rods. Some different choices like turn in concepts 2+2 with +2mm rods.

IAG is nice but I donít think their warranty is valid if you self install.

Last edited by pcampbell; 04-12-2020 at 09:47 AM.
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Old 04-12-2020, 09:27 AM   #110
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I think of a warranty as a sales pitch more then anything. If an engine is going to fail it's going to fail in the first 300 miles regardless of who installed it.
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Old 04-17-2020, 08:34 AM   #111
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Default Vortech supercharger for ~500whp? Si Too big?

I think itís nice but I canít afford to pay someone to install it anyway. So the warranty is moot or void. IAGs prices a little high to begin with.

Getting ready to spin this up to 6900rpm 100rpm increase at a time. Current redline is 6400. Will be curious to see how much air it flows up there.
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Old 04-19-2020, 10:55 AM   #112
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So I ended up with the Fluidamper, not sure that was the right decision. I thought it was slightly larger than stock diameter but it is stock diameter. The ATI is larger @ 5.5"

To put it in perspective the stock cast wheel on the SC will max out with my pulley combination @7k on the Fluid and @ 6700rpm on the ATI damper, both around 18psi.

With billet impeller , I'd rev the Fluid to 7500 and the ATI would go to 7200rpm, this is all assuming I can get it to not slip at this level of boost. I'd expect some serious rowdy numbers at 60k rpm on billet impeller, at least 23 psi, but maybe 25psi.

At this point I'm going to move forward on the Fluid, I can always switch later.

Last edited by pcampbell; 04-19-2020 at 06:44 PM.
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Old 04-23-2020, 06:37 AM   #113
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Default Vortech supercharger for ~500whp? Si Too big?



setup for larger BPV (1.25Ē), sticking with $20 Bosch until I have more money.

Huge air filter in fender well now, instead of tiny one in engjne bay


Waiting on devils own water meth nozzle, broke my snow nozzle because the wrench point is less than ideal

IAT relocated post intercooler- still need to order iwire MAF adapter

Fluidamper installed

One of these days I will paint the SC brackets and hack of the extra long threads on the Charge air clamps.

When itís back together Iíll start increasing redline 100 at a time. Might end up needing to do a clutch quickly.

I should have stuck some different valve springs in here when I had the motor out for cams but wasnít thinking about it at the same. Iím still on stock springs for now. AVLS springs are only $85 for a little piece of mind.

Last edited by pcampbell; 04-23-2020 at 06:44 AM.
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Old 04-25-2020, 06:48 PM   #114
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Default Vortech supercharger for ~500whp? Si Too big?

Went for a drive. New BPV return relocation is so much better than right after MAF. No more weird richness at light throttle.


Wondering if I should have gone with the bigger ati pulley ha!!!

Last edited by pcampbell; 04-26-2020 at 08:03 PM.
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Old 05-01-2020, 03:03 PM   #115
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What sort of power do you think you're making with this setup?

For quite a while now, I've been toying with the idea of building a setup with a small supercharger this is force-fed compressed air from a turbo once it spools.
It's not exactly new because a few people have actually done it in the past. In any case, I figure it would be an interesting project.
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Old 05-02-2020, 09:00 AM   #116
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Default Vortech supercharger for ~500whp? Si Too big?

It made 260 at the wheels before cams and the tune is pretty conservative on 14psi @6300rpm. This was on a hub dyno I should note. Also it is a pretty tired ej253.

After delta 1500 cams (current setup) I estimate itís at 285 at 14psi and 6300rpm.

Itís about to go to 16ish psi so I think thatíll easily put it into the low 300s @6300rpm

Then 18ish psi hopefully 340-350 @6700rpm which is what Iím planning to do this spring or summer. This might be the sweet spot (bang for buck) on this setup Iím not yet sure.

The full build would be like 25psi @7200rpm from a billet impeller and rev motor out, and I think it would push it up into the 400s pretty easily but I am going to go up in small stages to see how it does. At some point belt slip may become too big of an issue.

The Vortech is basically boost limited not flow limited. That is at max boost in stock form, around 19psi it will flow anywhere from 500-700 hp.


Does the Sc feed the turbo or vice versa? Sounds wild!

Last edited by pcampbell; 05-02-2020 at 12:20 PM.
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Old 05-04-2020, 05:02 AM   #117
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Always turbo feeding into a supercharger.

The supercharger only moves a certain volume of air, not matter what the incoming pressure of density is. A supercharger feeding into a turbo would never have a differing density of air incoming because it would always be atmospheric. That would simply choke a turbo at higher RPM as it is attempting to recompress the air.

A Turbo feeding into a supercharger means that the the supercharger begins lower RPM fixed compression, but is then "force fed" compressed air from the turbo, which is then recompressed (multiplied) in the supercharger for a much higher density.

The beauty is that supercharges are linear with RPM, which makes tuning similar to simply having a big turbo on a large displacement engine.

I'll post some photos of the others
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Old 05-06-2020, 08:43 AM   #118
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These guys got 500whp out of a Vortech h67b on an fa20. Iím asking for details, I have no idea how youíd get 20 plus psi out of that little SC which is rated for 2.0 pressure ratio.

Anyway I went for bigger crank pulley for more boost and itís slipping. These guys suggested the RPM belt (it doesnít stretch) so Iím waiting on that now.



https://dsportmag.com/the-tech/educa...ent-4902531099
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Old 05-06-2020, 09:18 AM   #119
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Quote:
Originally Posted by pcampbell View Post
These guys got 500whp out of a Vortech h67b on an fa20. Iím asking for details, I have no idea how youíd get 20 plus psi out of that little SC which is rated for 2.0 pressure ratio.

Anyway I went for bigger crank pulley for more boost and itís slipping. These guys suggested the RPM belt (it doesnít stretch) so Iím waiting on that now.



https://dsportmag.com/the-tech/educa...ent-4902531099
To me it sounded like that car can make 500whp and 20psi, but it isn't able to long term from lack of belt life. In their response it appeared they had zero confidence in that combination working with the pulleys that gripped well enough to make that kinda boost/power.
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Old 05-06-2020, 11:24 AM   #120
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Default Vortech supercharger for ~500whp? Si Too big?

I think It is just the grip treated pulleys that cause the belt life issues because they have a sandpaper like finish.

yeah the last combination that yielded 23 psi is a bad combo (grip treated pulleys with RPm belt). But the RPM belt only setup (stock pulleys) yielded 22 psi. That is pretty impressive.

Basically youíd either use grip treated pulleys and cheap belts or RPM belts and untreated pulleys. I think they are saying the RPM belts are a better solution because they last and yielded more power than grip Treatment alone.

I have had several grip treated pulleys and they seem to work but are messy (dusty) but This is the first time Iím going above 14psi.

Iím going to try the RPM belt and see what happens.

First will try 5.5Ē and 2.4Ē which is what is currently slipping.

If it doesnít work Iíll try 5.22Ē and 2.4Ē and rev it out and see what happens. The smaller crank pulley allows for a little more belt wrap and in theory is less resistance to the SC as the engine sucks in more air at any given impeller speed.

Last edited by pcampbell; 05-06-2020 at 11:49 AM.
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Old 05-06-2020, 01:51 PM   #121
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Here is how it might look if it grips. I drew a straight line across the peak boost levels. Assuming that is probably where it would be if it were gripping... maybe. ~16 psi is what I was expecting @ 6300rpm so it seems about right. Technically boost gain on centrifugal is not a straight line but close-ish.

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Old 05-06-2020, 02:18 PM   #122
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Quote:
Originally Posted by dahoseman View Post
Always turbo feeding into a supercharger.
I wonder if that's because the turbo is generally the part that's selected for peak power, and the supercharger is generally the part that's selected for performance at the low and middle parts of the RPM range.

In pcampbell's case, it's a centrifugal supercharger, designed for a larger-displacement engine, so it doesn't move a lot of air at low RPM and at high RPM it's capable of moving a lot more air than the engine can ingest. That's the opposite of the strengths and weaknesses of your average Roots or twin-screw setup.

But, if it were to feed into a turbo, it would be able to move a lot more air, more like what it was designed for. I'm thinking a turbo in the 40 lb/min range would be about right.

So in the mid-range, where the supercharger is only contributing a little bit, you'd get the midrange of a medium-size turbo. But instead of tapering at higher RPM like a medium turbo, power would continue increasing due to the supercharger getting into its efficiency range. Kinda like a compound-turbo system with a big turbo blowing into a smaller one, but without the extra exhaust plumbing.

This supercharger makes around 550whp on C5 Corvettes, which make around 350whp stock. A turbocharger that makes 350whp on its own would make this Subaru engine behave more like a C5's V8, putting the supercharger in the boost and flow range that it was designed for. 500-550whp seems reasonable with a suitable intercooler.

It it all works out it will be the coolest thing ever.
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Old 05-06-2020, 05:31 PM   #123
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I am not sure what would happen with a positive displacement supercharger upstream of a turbocharger. Depending on the drive ratio and blower capacity, the two machines could result in a condition where the turbo is sucking on the discharge of the supercharger with the supercharger not producing a whole lot of boost - just moving the flow.

My prior employer had a guideline against putting two centrifugal machines in series. Because they are constant head (delta pressure) machines, funny things can happen to flow through the system depending on the shape of the centrifugal compressor/pump curves. Dynamic operation away from a desired steady state operation can result in surging, etc. I would not try that here.
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Old 05-06-2020, 05:52 PM   #124
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The right way to twincharge is to use a positive displacement supercharger (think roots style) and a turbo feeding it.
The supercharger does not multiply boost but adds to it in all conditions, effectively increasing the engine displacement (thus the name). Basically the supercharger will make say 6psi. This will remain a constant and whatever the turbo makes will be added to the 6psi (the supercharger increases the pressure of any air it sees by the same 6psi in this example)
Because of this you need to spec a larger turbo because your engine acts like a larger one. Your 2.5l will act like, and require a turbo sized for a 3.2l as an example.
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Old 05-07-2020, 10:20 AM   #125
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Quote:
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The right way to twincharge is to use a positive displacement supercharger (think roots style) and a turbo feeding it.
The supercharger does not multiply boost but adds to it in all conditions, effectively increasing the engine displacement (thus the name). Basically the supercharger will make say 6psi. This will remain a constant and whatever the turbo makes will be added to the 6psi (the supercharger increases the pressure of any air it sees by the same 6psi in this example)
Because of this you need to spec a larger turbo because your engine acts like a larger one. Your 2.5l will act like, and require a turbo sized for a 3.2l as an example.
Agree on the turbo feeding a positive displacement supercharger. But can't agree that a supercharger makes a certain amount of boost. What a positive displacement compressor does is generate flow. The discharge pressure (boost) is a resultant of what is required to move the air through the engine.
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