Billet Aluminum Thermostat Housing for 4.0L 1GR-FE

Our Billet Aluminum Housing!


We are ditching the factory Toyota spring loaded thermostat for a readily available thermostat at any auto parts store with different temperatures available (Toyota stock is 180°, We will also offer a 160° for those who request it that are tuned/performance) Standard we will be including a high flow 180° thermostat. The thermostat we include is superior to a factory Toyota thermostat which relies on a rubber flap style seal. The thermostat included in our kit utilizes a brass seal design. The thermostat application is for GM 8.1L engines. They are readily available at any auto parts store in stock.

We also ditched the leak prone factory flat style Toyota o-ring. Our billet aluminum housing uses a generic thick gauge heavy duty o-ring that provides a stronger seal then the factory Toyota o-ring. The o-ring for our billet housing is readily available at any auto parts or hardware store as well. We will be listing the replacement part numbers for o-ring and thermostat and make the info readily available to everyone should it be needed.

I have changed a couple dozen factory Toyota housings due to failing plastic/leaking, allowing coolant to leak past the factory o-ring! In a couple cases I actually found the fingers broken that have the job of holding the thermostat in place! One instance lead to a blown head gasket due to the thermostat being sideways!

Other benefits. Our housing does not use the factory Toyota alignment pin which requires a “tang”to be molded inside the thermostat housing. Our billet housing does not have this “tang” resulting in a more free flowing housing. Less pressure and strain on the water pump and cooling system. A small increase in flow through the cooling system has multiple advantages. Internal combustion engines have colder and hotter spots naturally inside the motor, an increase in coolant flow reduces the hot spots throughout the motor. Leading to an increase in engine durability; common head gasket failure is due to these hotter spots inside the engine. With a more balanced/cooler engine temperatures come increased performance. Detonation, knocking, and/or pinging are less likely to occur. When this occurs the computer makes an attempt to protect to engine, it will retard timing and increase fueling, leading to a drop in performance/power/mpg. In tuned applications, timing may be able to be advanced more due to this increased cooling system performance.

And lastly we have a spot located for drilling and tapping our billet aluminum housing at request for an additional coolant temperature sender or switch!

You guys need to see it in person to appreciate the quality. All made in the USA, all US materials by a family owned machine shop!

Normal pricing we will be selling these for $150 free shipping plus tax on the store with thermostat of your choice assembled and ready to install.

I have been given permission from the business partners to initiate a Toyota group & forum $10 off presale. We have our first batch of 100 one week away from being ready.

Please send me a message, text or give me a call! 100% a normal car enthusiast stoked to have his part available to the world!

Cody Anderson
(805)432-1454

$140 free shipping & no tax on the presale!


Factory plastic housing


This is the plastic “tang” inside of the factory plastic housing.

For those interested! The housing will not be listed on the website for some time…
https://stores.unleashedcustommachining.com/
It will also be listed on the eBay store here!
https://www.ebay.com/str/reapercustoms805

 

any more pics, with it installed? any data showing the benefits?

 

Of course!!!!


We have completed a free flow test (unpressurized test) and our housing flows substantially better then the factory plastic housing! We are still waiting for the results on the pressurized test!

 

How does this clear with a trd/Magnuson supercharger? Apr had cut a recessed part on the back of the t stat on their thermostat housing. I am interested for sure.

 

I will be replacing my radiator, thermostat and hoses in the near future.

I am interested.

 

They are going quick! We have over 20 presold!

 

When will these be available?

 

We will be shipping out all presale orders no later then 10/31! I am hoping to get them out sooner!

They will not be available on the website or eBay until sometime in November!

 

Do you have any information about coolant temp differences between your setup and the factory setup? With your setup does the engine take longer to warm up? Thanks.

 

Interested also. Hoping it fits supercharged application.

 

It’s a housing, it will have no effect on coolant temps. It’s the thermostat that controls the coolant temperature. The flow rate difference with oem is really the only factor to review. Maybe also the wall thickness. The price is not worth the tradeoff to me as there are no known issues with the oem housing. When I first replaced mine at 100K, it looked in good condition. I replaced with a Motorad model. At 200k I replaced that one with an Aisin model. Again, the Motorad looked in good condition.

 

While running the Hi Flow 180° thermostat we have seen no issues! Vehicle warms up to temperature just as it should (we did time it!) The more free flowing design of our housing comes into play at once at operating temperature or under high load!

 

You are correct with regard to the thermostat regulating the temperature!

But I need to correct you with regard to flow. At operating temperature our housing will allow more coolant flow through the engine. Reducing engine hotspots. I don’t know how technically savvy you are on with tuning, timing, detonation, knocking, or pinging. I can assure you I am an ASE certified master technician with a pretty substantial experience completing general repair and maintenance of vehicles as well as serious performance modifications. Vehicles over 1000 hp. It makes a difference for longevity and performance.

and what does wall thickness have to do with anything?? Here’s a fun one for you, I’ve seen a mechanical fan blade explode and shatter a plastic housing while out off roading. Obviously at the time our billet housing was not available, had our billet housing been installed, his cooling system would have been intact and he would’ve been able to limp out as opposed to being towed.

The thermostat inside of our housing can be replaced for less then $10… How much did you spend on all of those plastic housings?

 

I didn’t say anything negative about the flow rate - I said the flow rate between the two is what you’d want to review, and you addressed that in post #3, albeit without posting any data to review. Wall thickness is important as it pertains to housing strength. The pressurized test results should address any concerns about that. Unless you can duplicate a fan piece hitting your housing, you cant say it would not have broken in the example you provided. My money is on your housing, but, it’s no guarantee.

I paid $27 for the Motorad thermostat, and $29 for the Aisin. I don't expect to replace it again, unless a fan piece hits it, but that’s why I kept the Motorad as a backup.

 

Do you have a pic of your thermostat housing on your supercharged vehicle?

 

plus this install manual
https://cdn.shopify.com/s/files/1/0...-004_RevE_Toyota_Tacoma_4.0L.pdf?v=1614725631

 

if this product works for this^^^ fella ill take one. his question is mine.

 

Make that another one

 

go take a pic of yours man to confirm! ours look close

 

I’m just using a stock Tacoma one at the moment. I have a 160 mishi I was going to use but this is much nicer