Rotrex C38-81 Supercharger??
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Rotrex C38-81 Supercharger?? Does anyone know if this unit flows enough to support a "healthy" low compression 383/396 LT4... say in the neighborhood of 550-600rwhp. W2W Powertrain sells these supercharges, I've e-mailed them about it's maximum potential, but they were very vauge with thier reply.
I know less than nothing about reading turbo/supercharger maps to determine the possible power they can support. I understand that the variables of a motor will affect how much power is made, but lets assume a 383/396 was built specificly to compliment this particular supercharger. I also understand that currently there is no kit being offered to allow this unit to bolt up to a F-body of any year, and that it would have to be custom built.
So... could it feed a 383/396?
And, to what "rough" power level?
Thanks
I know less than nothing about reading turbo/supercharger maps to determine the possible power they can support. I understand that the variables of a motor will affect how much power is made, but lets assume a 383/396 was built specificly to compliment this particular supercharger. I also understand that currently there is no kit being offered to allow this unit to bolt up to a F-body of any year, and that it would have to be custom built.
So... could it feed a 383/396?
And, to what "rough" power level?
Thanks
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As far as duals are concerned, I'd rather stay with the single unit due to space constraints. I would like to achive 550-600rwhp, any less would not be worth time/money/effort...any more would be icing on the cake. Keep in mind, it will be cooled with a front-mount A2A.
I know there are Vortech/ATI bolt-on kits that could easily reach these levels, but I would like as much botom end power as possible, and it appears as though these units perform better on the low-end then the aformentioned brands.
Plus, it's different. If I'm to spend the money, why not stand out in the crowd!
W2W claims 690 horsepower as the upper limit of this supercharger, not 650.
I know there are Vortech/ATI bolt-on kits that could easily reach these levels, but I would like as much botom end power as possible, and it appears as though these units perform better on the low-end then the aformentioned brands.
Plus, it's different. If I'm to spend the money, why not stand out in the crowd!
W2W claims 690 horsepower as the upper limit of this supercharger, not 650.
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To the layman, it would seem so. But I would like the opinions of the pro's regarding this units compressor maps... I think thats the right term. 
I just don't want to pull the trigger on a project like this if it's destined to fail from the start. A single turbo kit would be ideal, but there is not alot of choices to be had for our lowly LT1's.
I just don't want to pull the trigger on a project like this if it's destined to fail from the start. A single turbo kit would be ideal, but there is not alot of choices to be had for our lowly LT1's.
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Rock_Daddy - It's not that I dont value your opinion (quite the opposite), I value any opinion that helps me make a decision on a project of this size... and I assure you, it would be a sizeable project for me! 
I have looked into them to and I believe with out a dought that I could make 550-600 with one of these, but I am not you so take it for what it's worth and sometimes you just have to take a chance. So who knows you could pave the way for others with simular goals Good luck!
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Hey Guys.
The C38-81 unit will support 650 at the flywheel. Deducting 20% from that as a round about drivetrain loss figure could net you around 520 at the wheels as long as everything is up to snuff in regards to the combination and tuning. This would also require some sort of intercooler to obtain the results.
We will be offering a complete drive system which is based off of our Gen3 system.
It will include the blower, brackets, and the drive system and only require plumbing to be fabricated, tuning, and fuel system upgrades. I believe the drive system will be available within a couple months and will cost right around 3k which is inline with the universal Prochager kits.
The C38-81 unit will support 650 at the flywheel. Deducting 20% from that as a round about drivetrain loss figure could net you around 520 at the wheels as long as everything is up to snuff in regards to the combination and tuning. This would also require some sort of intercooler to obtain the results.
We will be offering a complete drive system which is based off of our Gen3 system.
It will include the blower, brackets, and the drive system and only require plumbing to be fabricated, tuning, and fuel system upgrades. I believe the drive system will be available within a couple months and will cost right around 3k which is inline with the universal Prochager kits.
Last edited by Kevin@W2W; Aug 3, 2006 at 09:36 AM.
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Originally Posted by lilbuddy1587
So what makes these units so much more efficient in the lower rpms ?
The step up ratio within the unit allows running rather high impeller speeds compared to other units creating boost quicker and producing more effiecency throughout the rpm range.
Originally Posted by Kevin@W2W
The step up ratio within the unit allows running rather high impeller speeds compared to other units creating boost quicker and producing more effiecency throughout the rpm range.
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Originally Posted by ls1_doc
if your after low end torque and u have to fab stuff anyways to make it fit why not look into a roots type blower?
It is common that roots type blower make good low end but tend to fall off a little upstairs.
With the Rotrex unit you get the benefit of low end operation as well as upstairs. This coupled with being more efficient than the typical 55 percent efficiency range of the roots type blowers makes the Rotrex a viable option for those who like to spin their motors a little higher and still have top end power.
No centrifugal supercharger is going to give you the low end of a Roots or twin-screw. All the centrifugals build boost as a function of rpm: If your max boost at 6000rpm is say 10lbs, then your boost at 3000 is going to be right around 3.1lbs.
After looking at the Rotrex datasheet, I'm thinking that their largest unit, the C38-81, will move less total air than either Procharger's P-1SC or Vortech's S-trim. On an LSx motor, I think a single Rotrex will be a disappointment - they are currently just too small.
Jim
After looking at the Rotrex datasheet, I'm thinking that their largest unit, the C38-81, will move less total air than either Procharger's P-1SC or Vortech's S-trim. On an LSx motor, I think a single Rotrex will be a disappointment - they are currently just too small.
Jim
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Kevin@W2W - The "Drive System" you will be offering sounds perfect for what I want to do, But I'm still a little leary about what a single C38-81 can support. Does the C38-81 fall between say a S-Trim and a T-Trim, or any other comparable units, and what CFM will it move?
Does Rotrex plan on ever building a larger unit?
Does Rotrex plan on ever building a larger unit?
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The Rotrex units do not act just like a roots or twin screw but DO offer similar low end due to it's design with very quick boost response in low rpm ranges as well as building a linear curve throughout the rpm range. It really is its own little animal in regards to efficiency per pound of boost.
As for some examples of the C38-81 unit.
Our concept GTO with a 389 inch LS2 based motor made just over 650 on the engine dyno
I laso have a customer who purchased our first intercooled truck system which uses our A2W intercooler. His combination is
6.0 liter stock short block
Unported LS6 heads
LS6 cam
Air intake
T-56
42.5 injectors
He is still tuning and needs a fuel pump but with just under 7 lbs of boost made 435 / 440 rear wheel numbers.
With some fuel system upgrades and around 10 lbs of boost the tuner is confident they will be able to reach 500 RWHP pretty easy.
Like I've said before with the right combination 650 flywheel horsepower can be obtained pretty easy with the C38-81 staying around the speed limit of the impeller which is 90K and equates to just about 1000 cfm.
At this time I have seen nothing of a larger unit in the words but they might be looking into something.
As for some examples of the C38-81 unit.
Our concept GTO with a 389 inch LS2 based motor made just over 650 on the engine dyno
I laso have a customer who purchased our first intercooled truck system which uses our A2W intercooler. His combination is
6.0 liter stock short block
Unported LS6 heads
LS6 cam
Air intake
T-56
42.5 injectors
He is still tuning and needs a fuel pump but with just under 7 lbs of boost made 435 / 440 rear wheel numbers.
With some fuel system upgrades and around 10 lbs of boost the tuner is confident they will be able to reach 500 RWHP pretty easy.
Like I've said before with the right combination 650 flywheel horsepower can be obtained pretty easy with the C38-81 staying around the speed limit of the impeller which is 90K and equates to just about 1000 cfm.
At this time I have seen nothing of a larger unit in the words but they might be looking into something.
Last edited by Kevin@W2W; Aug 3, 2006 at 09:37 AM.
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Upon further discussion I have found out my information regarding the max hp of the C38-81 is not correct.
The C38-81 will support 600 easy and 650 max hp at the flywheel.... I am sorry for the confusion and I corrected my posts above.
The C38-81 will support 600 easy and 650 max hp at the flywheel.... I am sorry for the confusion and I corrected my posts above.
