Comp Turbo CT4RX Hubless Turbos, Anyone?

[Car Cannibal]

CTRX COMPRESSOR WHEEL | Comp turbo

www.compturbotechnology.com

15% more flow by ditching the hub shaft
Water cooled for us street strip guys
No oil needed, their propriety grease every 3k miles

The CT4 has the compressor housing at 4" inlet and 2.5" outlet.

A 58/58 that has a potential for 775hp is on par with Garrett G30-770 so it's a street killer but probably spools faster due to less weight.

CTR4-5858 Turbocharger

Comp Turbo CTR4-5858 Turbocharger

www.compturbotechnology.com

Anyone got info like price, performance, durability?

 

[DSMPT]

CTRX COMPRESSOR WHEEL | Comp turbo

www.compturbotechnology.com

15% more flow by ditching the hub shaft
Water cooled for us street strip guys
No oil needed, their propriety grease every 3k miles

The CT4 has the compressor housing at 4" inlet and 2.5" outlet.

A 58/58 that has a potential for 775hp is on par with Garrett G30-770 so it's a street killer but probably spools faster due to less weight.

CTR4-5858 Turbocharger

Comp Turbo CTR4-5858 Turbocharger

www.compturbotechnology.com

Anyone got info like price, performance, durability?

I am not here to criticize their turbos, just sharing what exactly happened and my honest opinion.

I had a Comp Turbo CT4 6767 triple ball bearing about 10 years ago.
Since it's not the same model and it's older generation, my experience may be outdated.

Here is what happened.

I got the CT4 6767, I was told that the turbo doesn't like high oil pressure and doesn't need much oil, so I fed the oil from the head. It had a slight oil leak from turbine wheel ring seal. (The leak was very little like seeping and the drain was fine) I contacted them and they told me I need a restrictor and I bought one from them. I installed it and run a few miles and only one 40 psi pull. The turbo immediately died as soon as the boost pressure exceeded 40 psi. I sent the turbo to them and I was told "oil starvation". They said that they sent me a wrong restrictor as the feed was from the cylinder head. So they repaired the turbo but I needed to pay shipping (My case, it's international. Not so cheap)

I removed the restrictor and ran the oil feed from the head (Still had the same tiny oil leak from the turbine wheel), and went to drive the car. My EGT sensor got broken and a piece of sensor hit the turbine wheel (That was my fault) but they repaired by using warranty (Of course I needed to pay the round trip shipping). I appreciated.

Then I got the turbo back (I think they sent me a new core) and went to drive (Still had the same tiny oil leak from the turbine wheel). A couple of 30 psi pulls, no problem. The first attempt to 40 psi, the turbo immediately died again as soon as the boost pressure exceeded 40 psi.. I sent the turbo back to them and I was told "oil starvation". Of course I needed to pay the round trip shipping again.

Then I got the turbo back again and I fed the oil from OFH. But still had the same tiny oil leak from the turbine wheel, didn't matter if with or without restrictor, and what size of restrictor. Anyways it kept slightly leaking oil.
The first attempt to 40 psi, the turbo immediately died as soon as the boost pressure exceeded 40 psi... I sent the turbo back to them again and I was told again "oil starvation". But in this time they started to charge to repair. I refused because I was totally sure that the turbo was obviously misdesigned. And what's more they started to say that the turbo needs steady 50 psi oil pressure by using a pressure regulator. As soon as I heard that I gave up with them and I asked them to send the broken turbo back to me, but they refused to pay the return shipping even domestic shipping. So I told them no need to send back and I'm done with their turbo.

I decided to go different brand. Then I got a budget friendly Garrett GTW6765R. The wheel size is identical and I ordered it with the same size/AR turbine housing. Just different manufacturer.

When I received the Garrett turbo, I replaced only the turbo. Absolutely no change in anything, the same tuning, the same oil feed, the same oil drain etc etc. (Sure it had no oil leak at all) And I went to drive the car. I was like wow. It reaches to 40 psi about 800rpm sooner than the Comp CT4. I pulled the car with 50+ psi several times and I even blew the intercooler tank, but of course the turbo didn't die. I have had zero issue and I still have the same turbo since that day.

I just felt, there is a certain reason why many people don't use it.

 

[bastarddsm]

Oh man if you guys only knew the backstory on some of all this. Comp is like 5 years late to this party. There was/is a big patent lawsuit on the hubless technology. I'm guessing by how many places have it, the lawsuit went poorly for the patent holder. The hubless shit works though, did comp get the rest of the stuff right? who knows.

 

[Car Cannibal]

Oh boy, that sounds horrible for the patent holder, smells of unethical BS to not pay someone a small % of the future profits.

Racers are seeing a difference, dudes are keeping it on the DL in race classes to your say 67mm turbo is a 67 that flows like a 72 for to hubless area.

 

[bastarddsm]

Oh boy, that sounds horrible for the patent holder, smells of unethical BS to not pay someone a small % of the future profits.

Racers are seeing a difference, dudes are keeping it on the DL in race classes to your say 67mm turbo is a 67 that flows like a 72 for to hubless area.

There is more to it than that...

 

[Car Cannibal]

U.S. Patent for Hub-less and nut-less turbine wheel and compressor wheel design for turbochargers Patent (Patent # 10,914,231 issued February 9, 2021) - Justia Patents Search

A turbocharger for an internal combustion engine is provided, where the turbocharger includes a housing, a shaft, a turbine wheel, and a compressor wheel. The shaft is rotatable with respect to the housing and defines a centerline. The turbine wheel is mounted to the shaft and is disposed within...

patents.justia.com

Says Ryan Salenbien is the inventor
Filed: May 16, 2019
Date of Patent: Feb 9, 2021

Then looks like he assigned it to Apex

US Patent for Hub-less and nut-less turbine wheel and compressor wheel designs and installation/removal tool Patent (Patent # 11,598,294 issued March 7, 2023) - Justia Patents Search

A forced induction device for an internal combustion engine is provided, which includes a shaft, and a compressor wheel that is threadably mounted to the shaft, and a tool that is configured to engage one or more through bores in the compressor wheel to thread and unthread the compressor wheel...

patents.justia.com

Filed: Mar 1, 2021
Date of Patent: Mar 7, 2023

 

[Car Cannibal]

Does Suge Knight work for Apex?

 

[Car Cannibal]

Looks like these Hubless turbos will be available late Winter 2024. CT4RX 5858 seems like a killer street turbo at a possible 775hp. Similar to Garrett G30-770 (5855) but possible better spool due to lower weight and friction.

Hiroshi, sucks to hear that, you guys that push things to the edge always find the systems worst aspects. In a weird way you all help these companies find flaws that weren't on paper and then they upgrade pushing every company to compete at the highest standards so in a non disrespectful way, thanks.

The newer Triple X Ceramic bearing system has gotten better results from users, it didn't sound like you were running the newer system (which you could've literally helped them upgrade too). Sucks because I'm sure after your experience you're not looking to jump back on board Comp after Garrett, the most proven tech over time.

I guess we'll have to see if the Hubless with the increased flow will spool and perform better, then the most important, it survives.

 

[Car Cannibal]

So these Comp turbos use a different patented hubless tech vs Apex which is how they're able to offer this. I talked with a rep and these in the Triple BB are spooling even faster and making more power than the most recent turbos. The guys that got to test these out are ripping it and seeing great data. Pricing sounds like it's gonna be actually around Garrett G Series but I've yet to get an exact number.

No twin scroll T4 for CTR4X though, odd.

My next question would be...

Garrett and Borg Warner are giants in this industry, they've gotta be working on their version of this correct?

Is there a chance that Apex and Comp hubless patents have possibly covered this evolution and Garrett and Borg are gonna have to watch?