Topgunz ROTREX C38R Supercharger Kit

TopgunZ · 12-17-2021, 03:19 PM

Quote:

Originally Posted by Mr.K

I have been following his channel but it doesn't look like he is getting the kit anytime soon.

That is true, I've noticed after comparing multiple dynos of different kits your new kit has a powerband that is strikingly similar to that of your typical VQ turbo setup with the exception that one is obviously lag free. I would just like to hear feedback on how the new vs. older setups feel in comparison. Would be interesting to see how this kit responds to pulley mods.

When looking at those turbo graphs do you notice how the tq drops off hard up top? I found it interesting to see how the Rotrex holds the TQ.

And in my previous post I was talking about Superchargers when I said "other kits". But comparing it to turbos is fun too.

Mr.K · 12-17-2021, 05:47 PM

Quote:

Originally Posted by TopgunZ

When looking at those turbo graphs do you notice how the tq drops off hard up top? I found it interesting to see how the Rotrex holds the TQ.

And in my previous post I was talking about Superchargers when I said "other kits". But comparing it to turbos is fun too.

Sorry I forgot to mention I was comparing between 3-5k RPMs the way it ramps up but the supercharger having more area under curve around 2K because it doesn't ramp up as harshly as the turbo. Definitely, considering the turbos are appropriately sized the supercharger holds its ground better up top

. Honestly that was the main selling point for me, prior to your kit I was leaning towards a turbo oriented setup but seeing how your kit was the best of both worlds it was clear to me which one was better

.

TopgunZ · 12-17-2021, 08:23 PM

Quote:

Originally Posted by Mr.K

Sorry I forgot to mention I was comparing between 3-5k RPMs the way it ramps up but the supercharger having more area under curve around 2K because it doesn't ramp up as harshly as the turbo. Definitely, considering the turbos are appropriately sized the supercharger holds its ground better up top

. Honestly that was the main selling point for me, prior to your kit I was leaning towards a turbo oriented setup but seeing how your kit was the best of both worlds it was clear to me which one was better

.

This is great to hear. Glad the 100s of hours getting this system dialed in and fitting 10lbs of shiz in a 5lb bucket is worth it. These imports are hell in the bay. My turbo raptor was like working around an empty pool.

Did you guys know I have to remove and machine every Rotrex compressor cover just to get it to fit? That's the kind of spacial constraints I was against here. I also machine/bore out every inlet to make sure the intake is as capable as possible. It's hard to explain but it's the little things that matter.

Mr.K · 12-17-2021, 08:50 PM

Quote:

Originally Posted by TopgunZ

This is great to hear. Glad the 100s of hours getting this system dialed in and fitting 10lbs of shiz in a 5lb bucket is worth it. These imports are hell in the bay. My turbo raptor was like working around an empty pool.

Did you guys know I have to remove and machine every Rotrex compressor cover just to get it to fit? That's the kind of spacial constraints I was against here. I also machine/bore out every inlet to make sure the intake is as capable as possible. It's hard to explain but it's the little things that matter.

Seriously man your kit is living up to the hype

. And that's so true, the engine bays are super cramped, another reason why going TT would've been a nightmare for servicing

. That's the type of dedication and determination that we as a community appreciate

. Would love to hear all the little changes that went into this kit!

TopgunZ · 12-17-2021, 09:02 PM

Quote:

Originally Posted by Mr.K

Seriously man your kit is living up to the hype

. And that's so true, the engine bays are super cramped, another reason why going TT would've been a nightmare for servicing

. That's the type of dedication and determination that we as a community appreciate

. Would love to hear all the little changes that went into this kit!

That's lots of little secrets but can't spill them all.

One I'd like to point out that again people don't consider is we send a brand new machined ribbed idler pulley with the kits where the "other" SC kits require you to reuse pulleys from the car. If you have a high mileage car that bearing set is already stressed. Then there's the belt wrap that eliminated belt slip. Do you know how many anti slip pulleys I sell off my site to stillen and Soho kit owners? Alot. No need to purchase additional add ons to this Rotrex setup. It was designed with 800whp in mind from the beginning.

We are actually creating 3 different pulley setups now. You will be able to select the standard set, race set or Max set. We need to test these still but the max setup will come with Carbonite coated pulleys and cost more but will be reserved for built motors only.

Check out Carbonite coatings if you haven't seen or heard of it. There's also a high grip option called reichard.

We will always strive to improve. Most of the time I'm not even sure what that is until it happens. Lol .

Mr.K · 12-17-2021, 09:55 PM

Quote:

Originally Posted by TopgunZ

That's lots of little secrets but can't spill them all.

One I'd like to point out that again people don't consider is we send a brand new machined ribbed idler pulley with the kits where the "other" SC kits require you to reuse pulleys from the car. If you have a high mileage car that bearing set is already stressed. Then there's the belt wrap that eliminated belt slip. Do you know how many anti slip pulleys I sell off my site to stillen and Soho kit owners? Alot. No need to purchase additional add ons to this Rotrex setup. It was designed with 800whp in mind from the beginning.

We are actually creating 3 different pulley setups now. You will be able to select the standard set, race set or Max set. We need to test these still but the max setup will come with Carbonite coated pulleys and cost more but will be reserved for built motors only.

Check out Carbonite coatings if you haven't seen or heard of it. There's also a high grip option called reichard.

We will always strive to improve. Most of the time I'm not even sure what that is until it happens. Lol .

Nice to hear about the attention to detail you put in, about the pulley setups are these going to vary in size? I'm glad that you do, sometimes products are put out and never reach their full potential.

14Q60awdSPORT · 12-18-2021, 12:47 PM

Quote:

Originally Posted by TopgunZ

We are actually creating 3 different pulley setups now. You will be able to select the standard set, race set or Max set.

This is what I'm really interested in.

What would the psi of the "Standard" pulley be?

With my current setup/tune I could keep my map exactly same on a 16psi pulley and not be spinning the SC as much all the time.

Mr.K · 12-18-2021, 02:08 PM

Quote:

Originally Posted by 14Q60awdSPORT

This isn't 100% exact, but still a good illustration of what is happening and comparing the different boost "maps" Also added a typical TT for comparison.

A traditional "normal" centrifugal SC setup will choose a pulley for desired max psi IE 10 psi pulley will make 10 psi at 7500rpm, but only about 4.5psi at 3.5k rpm.

The topgunz kit will make about 23psi at 7500rpm, letting it make 10psi at 3.5k rpm. if you targeted 10psi the entire time you would bleed off through the BOV the excess boost over 10psi, so at 7500rpm you would be bleeding off about 13psi. your boost would follow the orange line until it hit the green line then follow the green line to redline.

at 3.5k rpm you are making 5.5psi more vs a traditional centrifugal SC setup which will result in a lot more torque/power in the mid range.

or compare orange to green following green vs the blue line, all the area in between those lines is the extra boost you are making through the entire curve despite both setups making 10psi peak.

and then you obviously have way more headroom to turn up the topgunz kit if desired without needing pulling changes.

That definitely cleared some things up for me thank you

. I like that you included a graph for comparison!

Quote:

Originally Posted by 14Q60awdSPORT

This is what I'm really interested in.

What would the psi of the "Standard" pulley be?

With my current setup/tune I could keep my map exactly same on a 16psi pulley and not be spinning the SC as much all the time.

I am interested in this as well, will the pulleys vary in size?

osmosizzz · 12-23-2021, 11:48 PM

Quote:

Originally Posted by TopgunZ

That's lots of little secrets but can't spill them all.

We are actually creating 3 different pulley setups now. You will be able to select the standard set, race set or Max set. We need to test these still but the max setup will come with Carbonite coated pulleys and cost more but will be reserved for built motors only.

Check out Carbonite coatings if you haven't seen or heard of it. There's also a high grip option called reichard.

We will always strive to improve. Most of the time I'm not even sure what that is until it happens. Lol .

Have you looked into grip-tec? I had a buddy run Carbonite and he was going through belts often. I went the griptec route and change belts once every 8-10 months. This is a 6 rib powering the rotrex C38R. Currently it holds 17psi with a wastegate duty set at 45

Love what you've done with the C38R on this platform btw. Uploaded is a dynongraph on what the C38R does on a 3.7L Honda single cam V6 for comparison. The C38R is a beast in such a small package

TopgunZ · 12-24-2021, 08:13 AM

Quote:

Originally Posted by osmosizzz

Have you looked into grip-tec? I had a buddy run Carbonite and he was going through belts often. I went the griptec route and change belts once every 8-10 months. This is a 6 rib powering the rotrex C38R. Currently it holds 17psi with a wastegate duty set at 45

Love what you've done with the C38R on this platform btw. Uploaded is a dynongraph on what the C38R does on a 3.7L Honda single cam V6 for comparison. The C38R is a beast in such a small package

That's what I wanted to use but they won't process my custom pulleys. They only sell the application on their pre made pulleys. At least that's the story i got from a guy that works there.

GrayGhost · 12-17-2021, 10:58 PM

Quote:

Originally Posted by Mr.K

Sorry I forgot to mention I was comparing between 3-5k RPMs the way it ramps up but the supercharger having more area under curve around 2K because it doesn't ramp up as harshly as the turbo. Definitely, considering the turbos are appropriately sized the supercharger holds its ground better up top

. Honestly that was the main selling point for me, prior to your kit I was leaning towards a turbo oriented setup but seeing how your kit was the best of both worlds it was clear to me which one was better

.

I think a great thing to emphasize about the topgunz kit as to why you are seeing more area under the curve is because the unique ability to bleed off excess boost especially when the original pulley that comes with the kit is sized to almost max out the blower. If this kit can hit 20psi by redline and you set it to 10psi, then you will hit 10psi by about midrange and theoretically you could keep a flat torque curve to redline. So this kit at 10psi will definitely look different than other kits at 10psi, unless the other kit it also running a 20psi pulley on a blower that could support that amount of flow but its limited to 10psi somehow.

Point being, out of the box it is definitely superior to other out of the box kits. (although with throwing a bunch of additional stuff to other kits, you could see similar graphs) and because of that feature it will look more like a turbo graph, yet be more predictable as you build boost.

Sent from my iPhone using Tapatalk

Mr.K · 12-17-2021, 11:45 PM

Quote:

Originally Posted by GrayGhost

I think a great thing to emphasize about the topgunz kit as to why you are seeing more area under the curve is because the unique ability to bleed off excess boost especially when the original pulley that comes with the kit is sized to almost max out the blower. If this kit can hit 20psi by redline and you set it to 10psi, then you will hit 10psi by about midrange and theoretically you could keep a flat torque curve to redline. So this kit at 10psi will definitely look different than other kits at 10psi, unless the other kit it also running a 20psi pulley on a blower that could support that amount of flow but its limited to 10psi somehow.

Point being, out of the box it is definitely superior to other out of the box kits. (although with throwing a bunch of additional stuff to other kits, you could see similar graphs) and because of that feature it will look more like a turbo graph, yet be more predictable as you build boost.

Sent from my iPhone using Tapatalk

I might be going out on a limb here so Aaron can chime in if I'm wrong but superchargers really only differ in the top half end when raising boost and that goes for all superchargers on this platform. If you look at the graphs on page 20 you can see that up to about 4.5k they are the same despite differing in PSI. This goes for other kits that I've noticed as well including Stillen, SOHO, etc. The biggest difference is really going to come down to the choice and type of blower which was the Rotrex C38R and the way the kit was set up. You won't see anything similar with other kits despite throwing everything at them (pulley mods, impeller mods, A2A conversions, etc.) because the powerband is on a whole different level.

TopgunZ · 12-18-2021, 08:28 AM

Quote:

Originally Posted by Mr.K

I might be going out on a limb here so Aaron can chime in if I'm wrong but superchargers really only differ in the top half end when raising boost and that goes for all superchargers on this platform. If you look at the graphs on page 20 you can see that up to about 4.5k they are the same despite differing in PSI. This goes for other kits that I've noticed as well including Stillen, SOHO, etc. The biggest difference is really going to come down to the choice and type of blower which was the Rotrex C38R and the way the kit was set up. You won't see anything similar with other kits despite throwing everything at them (pulley mods, impeller mods, A2A conversions, etc.) because the powerband is on a whole different level.

Actually the reason all 3 psi levels are equal up to high mid range is solely due to our unique operation of bleeding boost.

The 10psi map would normally not make 10psi until 7500rpm and therefore have lower numbers throughout. Yet here we see that the 10psi hangs with the 17psi power wise until the bov opens at 10psi somewhere around 4.5k where the other higher boost maps starting climbing away.

So 10psi on this kit will always have a better looking graph than another centrifugal charger at 10psi because we see all that boost ramp in the mid range instead of not getting to 10 until 7500.

Mr.K · 12-18-2021, 10:48 AM

Quote:

Originally Posted by TopgunZ

Actually the reason all 3 psi levels are equal up to high mid range is solely due to our unique operation of bleeding boost.

The 10psi map would normally not make 10psi until 7500rpm and therefore have lower numbers throughout. Yet here we see that the 10psi hangs with the 17psi power wise until the bov opens at 10psi somewhere around 4.5k where the other higher boost maps starting climbing away.

So 10psi on this kit will always have a better looking graph than another centrifugal charger at 10psi because we see all that boost ramp in the mid range instead of not getting to 10 until 7500.

So essentially the blowers are pushed hard until the BOV opens at their respective boost levels? Would we be able to play with this further if we wanted to push the graph to the left even further?

14Q60awdSPORT · 12-18-2021, 12:29 PM

Quote:

Originally Posted by Mr.K

So essentially the blowers are pushed hard until the BOV opens at their respective boost levels? Would we be able to play with this further if we wanted to push the graph to the left even further?

This isn't 100% exact, but still a good illustration of what is happening and comparing the different boost "maps" Also added a typical TT for comparison.

A traditional "normal" centrifugal SC setup will choose a pulley for desired max psi IE 10 psi pulley will make 10 psi at 7500rpm, but only about 4.5psi at 3.5k rpm.

The topgunz kit will make about 23psi at 7500rpm, letting it make 10psi at 3.5k rpm. if you targeted 10psi the entire time you would bleed off through the BOV the excess boost over 10psi, so at 7500rpm you would be bleeding off about 13psi. your boost would follow the orange line until it hit the green line then follow the green line to redline.

at 3.5k rpm you are making 5.5psi more vs a traditional centrifugal SC setup which will result in a lot more torque/power in the mid range.

or compare orange to green following green vs the blue line, all the area in between those lines is the extra boost you are making through the entire curve despite both setups making 10psi peak.

and then you obviously have way more headroom to turn up the topgunz kit if desired without needing pulling changes.

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***Topgunz ROTREX C38R Supercharger Kit***

Topgunz ROTREX C38R Supercharger Kit