PHR Lower Waterneck Adapter Rotator for 1993-98 Supra
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Select items are stocked in the USA — others ship from the manufacturer. Delivery calculated at checkout.
Problems In Need Of Solutions
Solutions provided by PHR
The 2JZ engine was not designed for single turbo setups, although in todays world, we all know single turbo is the king of the 2JZ world. The return inlet from the radiator was not oriented to accomodate big singe turbo setups, and therefore with it's position, we can have some real problems installing a top notch turbo manifold.
The Powerhouse Racing Lower Waterneck Rotator is a great solution for turning you waterneck away from your turbo and manifold, and down behind the alternator away from problems.
Runner Interference
With the lower waterneck in the factory position, there are two problems. First, the waterneck gets in the way of the runners on many turbo manifolds.
Turbo Interference
Second, the waterneck is blocking the ideal routing for the compressor outlet and intercooler piping.
Solved
The PHR Lower Waterneck Rotator moves the waterneck out of this terrible position, allowing the manifold to fit properly and the compressor outlet to be free of obstruction.
Improvement In Design
New Revision
Cooling system functionality
The thermostat has two functional parts to it: the thermostat valve itself, which opens at a certain temperature, and at the same time, a valve that closes off the radiator bypass hole when the thermostat opens.
Normal operation of the thermostat and waterflow is as follows: when the thermostat is closed, the bypass hole is open. This flows the water directly out of the head and back to the waterpump at low coolant temperatures, like during warmup and no water flows through the radiator. Once the coolant reaches the thermostat opening temperature (usually 180 degrees or 160 degrees), the thermostat opens and the bypass hole is closed off, forcing water through the radiator, and cooling it down.
The Factory Design
Take a look at the following picture to see what hole needs to be blocked off when the valve opens.
With other brand waterneck rotators, and even the earlier version of the PHR lower waterneck rotator, positioning of the thermostat has had to be moved away from it's proper location in the housing.
With these designs, the thermostat is moved away from the bypass hole to accommodate the rotator itself, and the thermostat installs in the lower waterneck boss. This position of the thermostate makes it so the bypass hole can never fully close. Even when the thermostat is open, the bypass hole is not closed and a large amount of the water is not allowed to go through the radiator and be cooled. This reduces the efficiency of the cooling system.
A Fix For The Problem
The NEW Powerhouse Racing Lower Waterneck Rotator solves this problem. The position of the thermostat remains in the factory location, allowing the thermostat to close off the bypass hole like it is supposed to and moving flow of all the water through the radiator, maximizing cooling system efficiency.
Hose Solutions
Once you've installed the waterneck rotator, you now have to address the hose routing. You CAN make the factory hose work, but it doesn't work well. It ends up way too long and routing is terrible and twisted in unapealing ways. You want a hose that is designed for a rotated waterneck, and PHR has produced one specifically for this need.
Specifications
| Vehicle Fitment | |
|---|---|
| Make | Toyota, Lexus |
| Model | Supra, GS300 (Aristo) |
| Chassis Code | A80, S160, S161 |
| Generation | MKIV (Mark 4), 2nd Gen |
- Brand
- PHR
- Platform
- Toyota Supra
- Engine
- 2JZ-GTE
- Category
- Radiators
- SKU
- PHR-01010602
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What customers say
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★★★★★
J-Spec Garage is my first stop for JDM parts now—fast shipping and no surprises.
Alex M.
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★★★★★
They actually took the time to help me choose the right setup for my GT-R. That alone won me over.
Brian S.
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★★★★★
Everything arrived well packed and exactly as described. You can tell car people run this shop.
Chris D.
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★★★★★
I've ordered three times now and it's been consistent every time—accurate, quick, and hassle-free.
Daniel R.
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★★★★★
Customer support answered my fitment questions in detail instead of just sending a link. That meant a lot.
Jason L.
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★★★★★
Parts for my Supra showed up on time and bolted right up. No guessing, no drama.
Kevin P.
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★★★★★
Site is easy to navigate and checkout was simple. Whole experience felt dialed in.
Nate H.
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★★★★★
Communication was excellent from order confirmation to delivery updates. I always knew what was happening.
Ryan F.
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★★★★★
These guys are clearly enthusiasts. The brands they stock and how they talk about them says everything.
Tyler N.
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★★★★★
I've dealt with plenty of parts shops—this is one of the few I trust with big-ticket items.
Zach W.
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★★★★★
My 240SX build depends on good vendors. J-Spec Garage has delivered every time so far.
Cody J.
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★★★★★
You can tell they care about the scene, not just sales. That's why I keep going back.
Dylan P.
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★★★★★
I had an issue with a manufacturer drop-ship and J-Spec Garage handled it for me. That's real customer service.
Josh H.
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★★★★★
The coilovers for my S13 came packed perfectly and ride exactly how they advertised. Super happy.
Kyle M.
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★★★★★
Grabbed both parts and merch—quality on both sides. Cool to support a shop that supports the community.
Sean L.
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★★★★★
I recommend J-Spec Garage to anyone building a JDM car. Solid parts and people who know the platforms.
Omar V.
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★★★★★
The RaceOnly parts I grabbed for my RX-7 were top-notch. Fitment was perfect and the car feels night and day better.
Aaron F.
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★★★★★
Finding legit rotary parts is tough, but J-Spec Garage came through with RaceOnly gear that actually delivers.
Blake S.
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★★★★★
Finally found a shop that understands rotary builds. The RaceOnly pieces I ordered have held up great under real abuse.
Jake P.
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★★★★★
Everything for my FD—from RaceOnly parts to small accessories—showed up clean, labeled, and ready to bolt on.
Mason K.
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★★★★★
I've ordered RaceOnly gear from other places before, but the service and communication from J-Spec Garage were on another level.
Noah V.
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★★★★★
The RaceOnly pieces for my RX-7 build fit exactly like they should. No grinding, no modifying, just bolt-on and go.
Owen T.
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★★★★★
It's hard to find a shop that really understands rotary builds, but J-Spec Garage clearly does.
Caleb M.
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★★★★★
Real rotary parts, solid communication, and no nonsense. Exactly what I want from a parts shop.
Isaac R.
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★★★★★
The Supra parts I ordered were clearly not cheap eBay stuff—quality brands and everything matched the listing perfectly.
Adrian C.
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★★★★★
I've been slowly building my MK4 and every order from J-Spec has shown up on time and ready to install.
Carlos N.
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★★★★★
They actually understood what I was trying to do with my Supra build and suggested parts that made sense, not just the priciest options.
Derek W.
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★★★★★
The turbo-related parts for my Supra came exactly as described and have held up great under boost. Zero complaints.
Javier S.
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★★★★★
I appreciate that they stock real-deal brands for Supra builds instead of filling the catalog with questionable stuff.
Miguel R.
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★★★★★
I'm picky about what goes on my MK4. J-Spec Garage earned my trust with accurate listings and solid communication.
Steven D.
-
★★★★★
I've had a great experience ordering Supra parts here—accurate listings, fair pricing, and quick shipping.
Marcus D.
-
★★★★★
It's refreshing to buy Supra parts from a shop that actually knows the platform.
Preston G.
-
★★★★★
The turbo and supporting parts I got for my Supra were exactly what I needed. Everything matched the listing.
Trevor M.
-
★★★★★
If you're building an RX-7 or Supra, this is a shop you want to know. RaceOnly parts for the rotary and quality Supra gear in one place is a win.
Victor H.
-
★★★★★
It didn't feel like I was buying from a generic online store. It felt like a shop built for enthusiasts.
Wyatt N.
-
★★★★★
Good communication, real brands, and parts that showed up when they said they would. Hard to beat that.
Zachary R.
-
★★★★★
J-Spec Garage is my first stop for JDM parts now—fast shipping and no surprises.
Alex M.
-
★★★★★
They actually took the time to help me choose the right setup for my GT-R. That alone won me over.
Brian S.
-
★★★★★
Everything arrived well packed and exactly as described. You can tell car people run this shop.
Chris D.
-
★★★★★
I've ordered three times now and it's been consistent every time—accurate, quick, and hassle-free.
Daniel R.
-
★★★★★
Customer support answered my fitment questions in detail instead of just sending a link. That meant a lot.
Jason L.
-
★★★★★
Parts for my Supra showed up on time and bolted right up. No guessing, no drama.
Kevin P.
-
★★★★★
Site is easy to navigate and checkout was simple. Whole experience felt dialed in.
Nate H.
-
★★★★★
Communication was excellent from order confirmation to delivery updates. I always knew what was happening.
Ryan F.
-
★★★★★
These guys are clearly enthusiasts. The brands they stock and how they talk about them says everything.
Tyler N.
-
★★★★★
I've dealt with plenty of parts shops—this is one of the few I trust with big-ticket items.
Zach W.
-
★★★★★
My 240SX build depends on good vendors. J-Spec Garage has delivered every time so far.
Cody J.
-
★★★★★
You can tell they care about the scene, not just sales. That's why I keep going back.
Dylan P.
-
★★★★★
I had an issue with a manufacturer drop-ship and J-Spec Garage handled it for me. That's real customer service.
Josh H.
-
★★★★★
The coilovers for my S13 came packed perfectly and ride exactly how they advertised. Super happy.
Kyle M.
-
★★★★★
Grabbed both parts and merch—quality on both sides. Cool to support a shop that supports the community.
Sean L.
-
★★★★★
I recommend J-Spec Garage to anyone building a JDM car. Solid parts and people who know the platforms.
Omar V.
-
★★★★★
The RaceOnly parts I grabbed for my RX-7 were top-notch. Fitment was perfect and the car feels night and day better.
Aaron F.
-
★★★★★
Finding legit rotary parts is tough, but J-Spec Garage came through with RaceOnly gear that actually delivers.
Blake S.
-
★★★★★
Finally found a shop that understands rotary builds. The RaceOnly pieces I ordered have held up great under real abuse.
Jake P.
-
★★★★★
Everything for my FD—from RaceOnly parts to small accessories—showed up clean, labeled, and ready to bolt on.
Mason K.
-
★★★★★
I've ordered RaceOnly gear from other places before, but the service and communication from J-Spec Garage were on another level.
Noah V.
-
★★★★★
The RaceOnly pieces for my RX-7 build fit exactly like they should. No grinding, no modifying, just bolt-on and go.
Owen T.
-
★★★★★
It's hard to find a shop that really understands rotary builds, but J-Spec Garage clearly does.
Caleb M.
-
★★★★★
Real rotary parts, solid communication, and no nonsense. Exactly what I want from a parts shop.
Isaac R.
-
★★★★★
The Supra parts I ordered were clearly not cheap eBay stuff—quality brands and everything matched the listing perfectly.
Adrian C.
-
★★★★★
I've been slowly building my MK4 and every order from J-Spec has shown up on time and ready to install.
Carlos N.
-
★★★★★
They actually understood what I was trying to do with my Supra build and suggested parts that made sense, not just the priciest options.
Derek W.
-
★★★★★
The turbo-related parts for my Supra came exactly as described and have held up great under boost. Zero complaints.
Javier S.
-
★★★★★
I appreciate that they stock real-deal brands for Supra builds instead of filling the catalog with questionable stuff.
Miguel R.
-
★★★★★
I'm picky about what goes on my MK4. J-Spec Garage earned my trust with accurate listings and solid communication.
Steven D.
-
★★★★★
I've had a great experience ordering Supra parts here—accurate listings, fair pricing, and quick shipping.
Marcus D.
-
★★★★★
It's refreshing to buy Supra parts from a shop that actually knows the platform.
Preston G.
-
★★★★★
The turbo and supporting parts I got for my Supra were exactly what I needed. Everything matched the listing.
Trevor M.
-
★★★★★
If you're building an RX-7 or Supra, this is a shop you want to know. RaceOnly parts for the rotary and quality Supra gear in one place is a win.
Victor H.
-
★★★★★
It didn't feel like I was buying from a generic online store. It felt like a shop built for enthusiasts.
Wyatt N.
-
★★★★★
Good communication, real brands, and parts that showed up when they said they would. Hard to beat that.
Zachary R.