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Discussion Starter #1 (Edited)
Full Disclosure: I purchased the BMR Reservoir at a slight discount ($25 off) with the intent of doing a review of the product and some IAT2 data.

Cliff Notes
Advantages:
* The tank is well made, quality workmanship and fits nicely in the typical location.
* Pre-drilled mounting holes are actually in the right location!
* Similar installation as NorCal tank, so if there are no instructions you can reference the sticky thread to figure it out
* Although slightly smaller than the NorCal tank, it is very large and appears to effectively double the coolant system volume, without creating fitment issues.
* Suggested Routing should provide the coolest temps to your intercooler (aka "Lid") when icing, such as at the drag strip.

Disadvantages:
* The screw-on lid requires their proprietary tool IMHO - I find myself checking coolant volume with the car running and the lid is HARD to get off with a warm engine bay. This is the biggest and most severe drawback - to me it reads like an excuse to charge an extra $25 for a special wrench; but honestly the BMR Reservoir is competitively priced even if you factor in the additional cost.
* Tank design may limit how some prefer to run their lines.
* Tank design may encourage internet nit-picking (ie "risk of cavitation") but I think this is highly unlikely
* Having a propriety tool to tighten the lid really is a pain in the ass. It should be included even if they have to raise the price $20.

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The box:






I had mine powder coated via Calico Coatings due to a shipping error, and they did a nice job. You can see the welded -AN male fittings (bottom is inlet, side is outlet), with the drain hose in NPT thread not yet installed (nor pictured). It's a quality piece and was well-packed for virtually no chance of damage. I purchased the -12 AN fittings direct from BMR and they are competitively priced.

The installation:

My instructions were either not included or misplaced by the coating company, however the installation is very similar to NorCal's posted instructions (CLICK HERE).

It is highly recommended that you remove the dual factory metal hard lines when installing the reservoir. You're going to do it, might as well do it now. You can get to most all the connections by removing the lower center splash tray from under the car to access the pump and heater Hx connections, and from the engine bay disconnect the battery post connection on the passenger side near the exhaust manifold - this allows you to gently feed the metal line assembly up and out (to be replaced by 3/4" rubber line):




You will need to trim several areas to get the box to fit properly, however it does fit very well with no rubbing against the cross member:



BMR suggests a specific routing to create the coldest fluid temps into the Lid when icing for the drag strip (likely the most common situation for CTSVOwners!); however some people such as road racers strongly prefer alternate arrangements for various purposes.

I used the BMR recommended routine in large part because it made it easier to join the heat exchanger to the Varimax pump. You will see in the following photos that it's a tight fit for hoses down there by the pump, so I reused the OEM hose vs risking a crimp in the softer 3/4" hose I bought locally. everything else has plenty of room no matter how you want to do it:

BMR recommended routing:



ETA: I finally settled on this routing*:


* Note: I routed my hoses through BMR tank "backwards," or inlet into the side and outlet to the bottom of the tank, so that the lower fitting drops straight down into my coolant pump for as little resistance to the pump as possible, or to "gravity feed" the pump. Doing this negates the ability to add ice as the coolant is not filtered for ice chunks in this manner. This is specific to the BMR tank design only. If you are going to ice, your "inlet" has to come in from the BOTTOM of the tank, and then flow out the SIDE of the tank so that ice chunks are filtered by the perforated tube.

My installation all finished up:
-removed incorrectly labeled photos-


Summary:
* I like everything about the BMR reservoir EXCEPT the need for their special "lid tool." it would be just as easy to machine a raised bar on the lid for hand-tightening rather than the recessed hard-on-the-fingers way they chose to.
* Some people feel there is a risk of cavitation or pulling air due to the "outlet" being slightly higher than the inlet. IMHO this is a non-issue on a properly topped-off system with minimal air trapped. The outlet is in the bottom 1/4th of the tank and I think it's highly unlikely for an air bubble to make it that far down as long as you are Shiny-Side-Up. If you run the tank less than 2/3 full (or have a leak), then I could see a risk of getting air trapped, but that's a maintenance issue. I personally think it's a non-issue.
* BMR's perforated tube design may potentially flow better than NorCal's mesh-screen design
* -12 AN fittings should equal the 3/4" NPT fittings on NorCal's tank; however material selection (such as brass) may significantly decrease the ID of NorCal's inlet/outlet, depending on what is provided.
* BMR is approximately 1.5 gallons vs NorCal's 1.7 gallons.
* IMHO any Reservoir/expansion tank will provide benefits, the specific tank you choose will be based on reputation, price, features and quality (likely in that order).

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So I looked at the data again to verify accuracy, mostly because some runs ended at 6200 RPM vs 6400 RPM, or had different ambient conditions, etc. So I've updated this post to show three separate, single-run comparisons of my original cooling setup vs the BMR reservoir only:




And the averaged results again:


* All runs were with a Varimax pump, ZL1 lid, and Track Attack; No tank vs the BMR Reservoir tank with 3/4" lines.
* MAX IAT2 was highest value recorded, typically 1-2 seconds after the run
* Additional data points for to illustrate recovery were added.
* Each set of runs (baseline vs BMR Reservoir) were matched to ambient conditions and starting IAT2, then averaged into the final comparison. I tried to make sure ambient conditions did not skew the comparisons either way, as I had 6-7 runs for each version.
* This was a reflection of my experience, your mileage may vary. Although I think we can safely say that the hotter it gets or the longer your pull is, the more benefit the reservoir becomes.
 

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Thanks for starting this thread. Good stuff. How much pressure (if any) does this cooling tank (system) build during normal heat soaked driving conditions? How do you bleed off the pressure before opening the screw off lid?
 

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Discussion Starter #4
Thanks for starting this thread. Good stuff. How much pressure (if any) does this cooling tank (system) build during normal heat soaked driving conditions? How do you bleed off the pressure before opening the screw off lid?
Honestly unless you're boiling coolant, this will be a relatively low pressure system. I personally ran the factory fill cap (5psi relief) for a margin of safety, however I suspect it's really not necessary unless you're going to see 200+ degree intercooler temps! Basically, I don't know enough about the system to tell you one way or another, but "anecdotal" experience here on the board suggests that you can run a closed system without ill effect. The factory filler T is relatively narrow.

Question: Are the -an fittings of choice (I see they offer -10, -12, -14) welded directly to the box?
Yes, the male -AN sized fitting is welded straight to the box, but you have to buy the proper female fittings of course.
 

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Very nice write up. I'm sure this will help tons of people including myself. Looks like you ordered with 12an bungs. Does the 3/4 inch hose fit the stock HX fine? Just curious if I can run 3/4 lines with stock pump and HX.
 

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Well detailed, in for your results. Might change my routing to this as well, but we have already talked this into submission in the other thread.

Looking forward to concrete data, the numbers don't lie. Well unless you want them to ... lol
 

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Discussion Starter #7 (Edited)
Well detailed, in for your results. Might change my routing to this as well, but we have already talked this into submission in the other thread.

Looking forward to concrete data, the numbers don't lie. Well unless you want them to ... lol
:D I will admit that the single greatest modifier in causing me to adopt the BMR routing system was the confined space between the Pump and the Heat Exchanger - the formed OEM hose fits so nicely in that space compared the alternative routing options that I just went with it.

On the off chance I do decide to "ice" at the drag strip some day, I'll be ready to go!

Very nice write up. I'm sure this will help tons of people including myself. Looks like you ordered with 12an bungs. Does the 3/4 inch hose fit the stock HX fine? Just curious if I can run 3/4 lines with stock pump and HX.

The factory filler / T-fitting, metal lines and intercooler lid are all 5/8" if I understand correctly. I am using a Varimax pump, ZL1 lid with modified fittings and the Track Attack aftermarket heat exchanger (which all utilize 3/4" line well), so I can't say for sure.

I think it's worth pulling out the metal lines even in stock form as they are a restriction (narrow, 4-5 unnecessary bends).
 

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Discussion Starter #9
Hmmm... first "after" run only showed a few degrees of lower IAT2 - not the slam dunk I was expecting.

Will get a few more runs in to average out the data....

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Random,I am also going to be installing a BMR tank/Zl1 Lid combo.. Would a 10ft braided hose be the correct size to go with for the BMR tank ? I know you didn't go braided but figured you would know the length.
 

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Is the drilled tube welded to the tank on both ends?
 

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Discussion Starter #14
Random has a way to get by with less length.


Sent from my local E85 station.
My wife disagrees. Apparently "knocking the bottom out of it" isn't good for her. : (

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Discussion Starter #15 (Edited)
Random,I am also going to be installing a BMR tank/Zl1 Lid combo.. Would a 10ft braided hose be the correct size to go with for the BMR tank ? I know you didn't go braided but figured you would know the length.
Hmmm... are you bypassing the metal lines going straight to the pump and hear Ex?

I'd say 4 ft from pump to tank, 4 ft from tank to lid, and 5-6 feet + a 90 degree end from the lid to the heat exchanger - this way you can avoid extra connections.

14 feet total and you should have a little left over; with braided I'd hate for you to come up short. ETA I verified that these lengths are correct, for how I routed things.

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Random has a way to get by with less length.
lol - I would ask how you know that,But i don't want the answer!

Hmmm... are you bypassing the metal lines going straight to the pump and hear Ex?

I'd say 4 ft from pump to tank, 4 ft from tank to lid, and 5 feet + a 90 degree end from the lid to the heat exchanger - this way you can avoid extra connections.

13 feet total and you should have a little left over; with braided I'd hate for you to come up short. I will try to confirm tomorrow though
The braided lines come in 6,10,20 Feet only i believe. I'm going to run -12 lines everywhere if possible.
 

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Discussion Starter #17
lol - I would ask how you know that,But i don't want the answer!



The braided lines come in 6,10,20 Feet only i believe. I'm going to run -12 lines everywhere if possible.
I just checked and my estimations were more or less right on. If anything, you might need 6 feet of line going from the lid to the heat exchanger, depending on how you route things (still 4/4 for the other sections).

You're cutting lines no matter what, so the safe bet is getting 20 feet and trimming to length.
 

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On stock setup I made it work with about 6ft. Think I bought like 8 and had some left over.
 

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Just FYI, I've never needed the tool to take my lid off (when I had the box), you can use your fingers just as easily. It was actually my idea to come up with the handle to allow for me not to have to touch the lid when it's hot when putting ice in at the track.
 

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Discussion Starter #20
Just FYI, I've never needed the tool to take my lid off (when I had the box), you can use your fingers just as easily. It was actually my idea to come up with the handle to allow for me not to have to touch the lid when it's hot when putting ice in at the track.
That is BMR's position as well: "you don't need it."

However, as someone who just installed it, has tried to install and remove the lid multiple times while on the car topping off the system over the past few days... I will disagree. IMHO it's a limiting design relative to a typical user, and limits how firmly I can snug up the lid (and still get it off later).
 
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