Who's done a coolant reroute?
#21
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We have added a much simpler coolant re-route to our systems.
Here is a diagram of the current miata coolant route.
http://www.bellengineering.net/Image...olantflowB.jpg
Here is a good way to fix it.
http://www.bellengineering.net/Image...eoute_flow.jpg
Or you can interrupt the coolant line before the heater and run it to the radiator inlet.
Stephanie
Here is a diagram of the current miata coolant route.
http://www.bellengineering.net/Image...olantflowB.jpg
Here is a good way to fix it.
http://www.bellengineering.net/Image...eoute_flow.jpg
Or you can interrupt the coolant line before the heater and run it to the radiator inlet.
Stephanie
I'm sure BEGI's is better than the OEM and OEM is probably fine for 99% of people out there. I only did mine because I had the engine out and figured what the hell. But I figured the point of a proper coolant reroute is to pump all the coolant across the engine like the FWD cars.
#22
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The original coolant reroute came about to even the cooling of the engine NOT to reduce engine temps. IOW the average temp is the same, but in the OE configuration temps range from cylinder to cylinder with number 1 being the coolest since it receives the greatest flow and number 4 being the hottest because it receives the least flow. With the reroute, coolant flow is encouraged to flow more evenly through all paths to the rear of the head.
Kia addressed this when they used the originally fwd-only FE in their rwd Sportage by changing the coolant passage bores in their head gaskets. By reducing the bores on at the front and enlarging them at the rear cylinder(s), they forced more coolant to the rear even though the FE got a front rad exit- like the Miata's OE configuration. Not the ideal fix, but cheap and effective.
It looks to me as though the point behind the BEGi reroute is reduce overall engine temps by eliminating the return/recirc path of the heater core- albeit at the price of speedy interior heat. IMO I would find other means to reduce engine temps first- but that's because I want my heater to warm up quickly.
Kia addressed this when they used the originally fwd-only FE in their rwd Sportage by changing the coolant passage bores in their head gaskets. By reducing the bores on at the front and enlarging them at the rear cylinder(s), they forced more coolant to the rear even though the FE got a front rad exit- like the Miata's OE configuration. Not the ideal fix, but cheap and effective.
It looks to me as though the point behind the BEGi reroute is reduce overall engine temps by eliminating the return/recirc path of the heater core- albeit at the price of speedy interior heat. IMO I would find other means to reduce engine temps first- but that's because I want my heater to warm up quickly.
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I did the coolant reroute when installing the 1.8 Escort GT engine in my 91. I used the thermo housing top from the 1.6 and ran the large hose around and up front. Instead of using one complete piece of hose I found that chrome finished sink traps made of brass from Lowes is the exact diam. and so I fit them in where needed. Works good and the chrome looks good. This car is not turboed nor raced but it warms up quick and the temp never moves no matter how hot the day or how hard the drive. The escort engine normally has the outlet for heater and rad at the back of the block (front wheel drive) so the only challange was running the hose. The heater hoses run the same as original. FWIW
#24
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I did the coolant reroute when installing the 1.8 Escort GT engine in my 91. I used the thermo housing top from the 1.6 and ran the large hose around and up front. Instead of using one complete piece of hose I found that chrome finished sink traps made of brass from Lowes is the exact diam. and so I fit them in where needed. Works good and the chrome looks good. This car is not turboed nor raced but it warms up quick and the temp never moves no matter how hot the day or how hard the drive. The escort engine normally has the outlet for heater and rad at the back of the block (front wheel drive) so the only challange was running the hose. The heater hoses run the same as original. FWIW
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IMO, unless you're going to pull the core out, I wouldn't bother just not running the lines.
Personally, I'd keep the heater system functional. It's actually a good place to slough heat. Say you're on the highway or track and you see the temp needle climb up where you don't want it to be. If you turn the heater on, it will take some heat energy out of the coolant, and hopefully give you enough time to get off the road before something bad happens.
Personally, I'd keep the heater system functional. It's actually a good place to slough heat. Say you're on the highway or track and you see the temp needle climb up where you don't want it to be. If you turn the heater on, it will take some heat energy out of the coolant, and hopefully give you enough time to get off the road before something bad happens.
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I've read the website. I'm new and did preface my statement with "I may be wrong". The Begi "bypass" fixes the interference but the reroute is also part of that. It would appear that they are simply taking the hot water returning from the heater and running it around the intake side of the engine and t-ing it into the inlet side of the radiator. They don't appear to be rerouting the flow in or to the block. Again, this wouldn't be intended to fix cooling issues. Maybe Steph can clear this up.
#32
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I can't see how that improves coolant flow across the the entire engine when the top radiator connection maintains it's OE position.
The heater core output move will delay the time it takes the heater to warm up since the coolant is no longer bypassing the radiator. Looks like the resolution solves one problem by creating another (slow warm up on the heater). Amount of work is similar since both run a hose from the back side to the front. One eliminates plumbing, while the other swaps to an fwd coolant cap that will move the tStat to the rear and the OE rear cap to the front to feed the heater.
The heater core output move will delay the time it takes the heater to warm up since the coolant is no longer bypassing the radiator. Looks like the resolution solves one problem by creating another (slow warm up on the heater). Amount of work is similar since both run a hose from the back side to the front. One eliminates plumbing, while the other swaps to an fwd coolant cap that will move the tStat to the rear and the OE rear cap to the front to feed the heater.
The heater output re-route will not affect heater function due to the fact that it is still drawing fluid from the back of the cylinder head. We are just cooling the warmer fluid from the heater before it goes into the engine. Thus resulting in lower temps. In reality is this a huge change? No. However every little bit helps, even if it is 2-3%.
The diagram on page one is a good system with one exception. The heater output needs to go to the radiator inlet for cooling prior to entering the engine. Are you proposing moving the front thermostat?
Ben is correct, the by-pass removes the lower radiator hose to make room for turbo parts. The Re-route is to cool the engine - somewhat. Every little bit helps.
We do have a "race" re-route in the works that will run it differently than the one on the website. The "race" re-route is more of what the DIY'ers do. We'll have more info on that in a week or so. There is a big project in the works.
Stephanie
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The heater output re-route will not affect heater function due to the fact that it is still drawing fluid from the back of the cylinder head.
We are just cooling the warmer fluid from the heater before it goes into the engine. Thus resulting in lower temps. In reality is this a huge change? No. However every little bit helps, even if it is 2-3%.
The diagram on page one is a good system with one exception. The heater output needs to go to the radiator inlet for cooling prior to entering the engine. Are you proposing moving the front thermostat?
IMO if one was looking to control elevated coolant temps, the environment should first be identified. Then focus on optimizing the system for that environment by any of the following: filling all the gaps left between OE parts, parallel fan wiring, higher flowing fans, different coolant mix, larger rad, etc. - rob
#36
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Once the car is warm, there is no difference in heater function.
#37
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So basicly to get this to work youll need a 2 way valve that switches just below thermostat opening temp...
On startup the coolent runs oem, when hot trough the radiator.
I don't think the disign of the miata is poorly as the coolent will be extracted at about the same flow on the front and rear of the engine.(hole in thermostat is not that big)
The only thing to worry about is the 'warm' heater return line.
On startup the coolent runs oem, when hot trough the radiator.
I don't think the disign of the miata is poorly as the coolent will be extracted at about the same flow on the front and rear of the engine.(hole in thermostat is not that big)
The only thing to worry about is the 'warm' heater return line.