Just got the car back last nite with the VodooII installed. Dyno shows 185 hp. Its a different animal now. No longer do I fear minivans.

While under boost, my temp gague rises from just left of the centerline to anywhere between just right of the centerline to as far as 3/4 of the way towards the "H". My undertray broke/cracked apart during the installation. Where is the best place to pick up a replacement. I know this part is critical to cooling based on my reading earlier posts here I am running 70% water with water wetter, about 30% coolant. I don't have a coolant rerooute. My radiator was replaced 3 years ago with a new factory replacement. Thanks

 

I don't think in this instance the undertray is the issue...

 

Brain are you thinking coolant re-route? The swing of the temp gauge 3/4 towards hot was after climbing a mountain in PA under boost. Big hill.

 

You are correct.

You have to consider the path of the coolant relative to the position of the coolant temp sensor. The only coolant that passes the temp sensor goes through the heater core, and then back into the engine. Consider that a large portion of that coolant gets reheated again on its way back through the engine without actually going through the radiator, only to pass the temp sensor again, and then repeat the process. The rear of the engine gets quite a bit warmer than the front under the turbo loading. This is the leading cause of detonation in cylinder 4 in cars before Coolant Reroutes began widespread popularity.

Now consider the Coolant reroute. All coolant that goes into the engine passes by the coolant temp sensor. All of the coolant passes through the complete engine instead of coming in from the front, passing cylinder 1, and exiting out the front. The cooler charge from the radiator passes through and absorbs heat from the entire engine, eliminating temperature variation from front to rear. Since the creation of commercially available kits, the coolant reroute has become one of the most popular upgrades for turbocharged cars; some consider it about as mandatory as a clutch replacement. If you've saved up the money and are considering upgrading your radiator, it's recommeneded that you spend that money on a coolant reroute instead. It's a pain in the *** to install the rear water neck, but it's an extremely effective cooling solution.

Next time, while climbing that hill, turn your heater on full hot. If this solves your problem, then you really need to put some consideration into a coolant reroute.

Also, if you're using a 13psi radiator cap, I would recommend installing a 16psi cap, available on the shelf at most/all major auto parts stores. Boiling coolant creates air pockets which significantly decreases the cooling capacity of your coolant. The higher pressure radiator cap will increase the boiling point of your coolant. If your coolant is boiling at the rear of the block, this $8 upgrade should be the only solution in your consideration set. Install cap, see what happens, then get the coolant reroute.

 

have any pics of the turbo install, engine bay?

 

Thanks. Will get some pics this week or weekend. Turning on the heater did help. I did go with a 16 PSI cap when I had the turbo put on this past week

Looks like I'll go with a reroute instead of a new upgraded radiator. I see FM and BEGI both have one ( a reroute). I ordered a new undertray as well as the old one was basically cracked in 3 places. Thanks for the advise.

 

theres a bunch of pictures on flyin miatas website of this kit

 

I don't think the cooling system is working to par with/without the undertray. I wasn't going as far as suggesting the coolant reroute...as that's the not issue we are trying to solve here. What I was suggesting is that it's probably as simple as the rad cap not sealing or a pinhole leak in the system or air bubbles.

 

That is what I was thinking as well. Since I picked up the car last nite, almost in the dark, and the rain, I did not check the radiator or the overflow tank. I know it can take some time/refills/etc to get all of the air out of there and get the tanks really properly full. That's on my list for tomorrow am when i get home and can take a look at the car in the garage. The above, and the new undertray, will be my first steps. Again, thanks for the input and I will report back by end of week.

 

I generally start the car with cap off, wait until the thermostat opens and coolant level in the radiator will start falling. Begin filling the radiator until it doesn't take any more coolant. Turn off car, replace radiator cap.

 

i also squeeze the upper and lower hoses after the thermostat opens.

 

"burping" the system as these guys have described it, makes a HUUUUUUGE difference if you have air bubbles in teh system.

Happened to me twice already. And I have a coolant reroute and everything working properly. Start the car up, within a few minutes it pegs H and temps are at 120 C. I was
Burped system.
Runs like a champ regardless of outside temps.

 

Indispensable tool: http://www.amazon.com/Lisle-24610-Sp.../dp/B001A4EAV0

You can pick this up at your local autoparts store for $20. The best money I ever spent.

 

Agreed. Those buckets are amazing

 

Definitely burp the system, but don't discount the importance of that undertray like some do. It is absolutely critical to the flow of air through the radiator.

 

Get a real water temp gauge. I haven't cracked over 90* on my turbo car at the track. Mind you our ambients are only 20*-25*

but still.

 

I have a small update that certainly validates everything stated above. Last nite, after getting home from JETS/GIANTS preseason game, I checked the radiator and I could see the fact that coolant level was low. I added at least 18 ounces of water. Driving to work today the temps were much more constant and close to mid level on the factory gauge. I'll do some more burping over the next few days and install the new undertray upon arrival. I'll get pics taken this weekend once I get some time. Thanks again for excellent advise.