Does anyone with the AST emlimination kit race their car at the track (road course), and if so have you had any problems, issues, concerns? Also I do have the AST elimination kit and does anyone think I will have troubles racing at the track (this would be 2 maybe 3 times a year at a road course going 8-10ths, not ***** to the wall) TIA let me know if I need to refrase anything

 

Yes.

Aside from the initial air purging of the system and poorly routing a hacked overflow line which lead to coolant not being sucked back in, there weren't any adverse affects that I could see.

I did it because I <cough> ended up blowing up my AST right before driving up 6 hrs to Summit Point this past summer </cough>.

I bypassed it in the parking lot where my car lay in a puddle of coolant and used the stock overflow lines joined together to make an overflow line long enough to reach the bottle from the filler neck. FWIW, it was too long and I kept suffering from coolant overflowing because it wouldn't get sucked back in. Car is on jackstands now, and I'm shortening and re-routing the line in hopes of curing that.

While on track, I did have the coolant buzzer go off, but water temp stayed normal. Car behaved better a few months later at another track weekend and I only had to top off the coolant a little bit since I changed the radiator pressure cap and mucked with the aftermarket temp sender.

Nope. Contrary to rumor, there aren't baffles in the AST as previously thought. It is just another failure point (unless it is made of metal and even then, those hoses are just extra coolant hoses under pressure).

If you don't have an aftermarket radiator, you might want to consider doing that when you do the elimination, since you'll end up losing coolant when you undo the lower radiator line connecting to the AST.

Regards,
--Ashraf

 

I've done about 12 hours total hours of racing on various tracks with my FD with the AST Bypass Kit (aka bolting on the filler neck and overflow cap from the 2nd gen RX7 and capping off the lines to the AST) with no adverse problems to the best of my knowledge.

 

Do either of you guys have an aftermarket water temp gauge? By the time the stock gauge starts to move you are well over 210*. FDs are so undercooled as it is, I would say that further compromising the system is not a great idea. I would strongly suggest an aftermarket AST rather than eliminating the feature. Either way, get an aftermarket gauge, and you will see just how high your temps are. I have a road race FC, with a custom AST. The AST was good for ~5-7* of temperature reduction in my system. This is on the track, on the street, with stock motor output it will be O'k, but any increase in temps is shortening the life of your O rings. Carl

 

I am thinking of buying a koyo radiator and running evans coolant in my car before I get on the track with it. Anyone think I will have severe issues with this without an AST

 

Are you at stock output, or have you done some mods? At stock output you s/b fine for an occasional track day. That said the heat problem is one that manifests itself over time, at stock output, if your cooling system is in good order you will not see temps that will warp the housings, but you will be shortening engine life. I would run~15% standard coolant, a bottle of Water Wetter, and the balance distilled water. This should be superior to the Evans from what I have observed at the track( I've never used Evans, but I know some who have). Still, get a water temp gauge, you need to have one anyway, if you are going to track the car, and you might as well track the improvements to your system as you go. What is the resistance to an aftermarket AST? I would also search the forum for "cooling mods" You'll get some more ideas on keeping your carcool. Hope this helps, Carl

 

these are my performance mods to the car as of right now, but the car also has the ast elimination. The car holds temps awesome right now but that has just been on the street

- B&M Short shifter
- ACT street/strip with hd pressure plate & stainless clutch line
- reasonated midpipe
- silicone hose job
- PFS exhaust
- PFS boost gauge
- greddy turbo timer
- greddy SMIC with Pettit intake duct & SPAL fan
- Greddy 2 piece kit & Elbow
- Hard pipes
- Apexi intake
- stillen cadmium cross drilled rotors
- Hawk HPS pads x 4
- downpipe
- Cusco strut tower bar
- Apexi PFC (professionaly tuned for 12.5 psi)
- Efini Y-Pipe
- Walbro fuel pump


do you recomend just buying an aftermarket ast along with a radiator, I think I am going to be buying the koyo, do you think I will be fine with the koyo and my current mods or should I pick up an AST as well?

 

I would use an aftermarket AST, there are many out there, but they are way over priced. Here is a link to a more resonably priced one. http://www.secureperformanceorder.co...ProductID=2522
I'd use the Koyo with the coolant as I suggested. Why do you think your temps are OK? If you are only relying on the stock gauge, you do not know what your temps are. I have a stocker, and an Autometer, at ~120* my stocker reads 1/2, at 215, it still reads 1/2, at 220-230 it reads 2/3(this is a dangerous temp IMHO), by full hot on the stocker you are doing signifigant damage(235-240+). Hit that two or three times, and kiss your motor goodbye. The stocker stays stable by design so that the average owner does not become alarmed by fluctuations. Buy a good mechanical gauge for water, and preferably oil temps(~45.00 each), and you will see what I mean. Also, you will be able to see if you need additional oil cooler capacity. If the temps are equal, your system is balanced, and is the best that it can be, if one is signifigantly hotter than the other, then you know where to focus your efforts. If it were my car I would add a second oil cooler as well. You can buy an R1 second cooler, or you can buy an inexpensive one from Summit. No need IMHO to buy a 300.00+ cooler. Do not skimp on lines though, as your engine is depending on these. Also you could use a TII oil cooler as your Aux. they are very high quality and can be had for ~50.00.
The point of all this is that your engine will last longer. There are alot of guys running inferior cooling systems, and saying they work fine. I'll bet you none of them have an aftermarket temp gauge, or they'd think different. Regards, Carl

 

the reason I said my temps are fine on the street is because I am reading them off of the PFC commander, right now I don't even boost if I see anything above 92-95 celcius, I am pretty conservative when it comes to driving the car on the street, but when I get it to the track I want to be able to run it without having to worry too much. Thank you for your responses, any other advice is more than welcome

 

I don't understand why the AST would help you cool any better.

 

John, think of it like this, when you boil water, you create air bubbles, every where there is an air bubble, there is no coolant, less coolant volume= less cooling potential. To take it a step further, everywhere an air bubble is touching the engines cooling passages, (imagine the bottom of a pan with boiling water in it) there is far less cooling effect. This is where the Water Wetter comes in. What Water Wetter does is prevent those air bubbles from adhering to the metal surfaces, thereby increasing the cooled surface area. If you think this is no big deal, put a frying pan on the stove, put an inch of water in it, and bring it to just below a boil. What you will see is alot of bubbles, if you add up that surface area, you will find that it is a signifigant percentage of the total surface area. Hope that explains it, feel free to ask for clarification if something I posted did not make sense to you. Regards, Carl

 

Yes, I have an aftermarket gauge.
I essentially have a stock car and (downpipe and catback) and run stock boost.
The temps I run are satisfactory to me.

I have seen 226-230 at most on really hot days in North Carolina. I've been known to fire up the heater and run it to the windshield to help cool things down, as well as run the fans full time, and that keeps things in check.

Yes, I realize that those temperatures are not ideal, but it isn't overheating, and that's with an Autometer gauge, which I don't consider very accurate.

At some point, I'll redo the cooling system, and will consider an AST again, when I can make the links between the radiator and AST "reliable".

For now, I'll run what I've got...and it's not like I spent thousands of dollars on a brand new engine. I'm pushing 90k on the stock engine/turbos. I know the dangers and am willing to deal with the consequences. I do agree that extra cooling capacity for both coolant and oil is a good thing, but it is less of an issue with a stock car.

 

Have I run without an AST at the track?

Well, I actually lost the AST while *at* the track!

This was at VIR year before last - I had just come of the track, drove the FD around the pit for a while to let her cool down, parked it and put the hood up and went to get lunch. Things heat soaked and there was just enough increase in pressure to crack the seam on the AST.

Luckily, a friend had a spare FC filler neck and we did the bypass in the pits. I was back on the track that afternoon.

The only issues I have had since then is that the system takes a little longer to burp the air out when I drain/change the coolant. Once it is properly burped, I have no problems.

Car is tracked about twice a year, plus an auto-x or two.