Banzai Racing 20B GT42RS 93 FD
06-18-12, 07:03 AM
#277
I have not got around to the undertray yet. I do not have any cooling issues, so it slips down the list of priorities.
I have been concentrating on replacing nearly every interior piece with brand new parts from Mazda, that adds up fast.
I have been concentrating on replacing nearly every interior piece with brand new parts from Mazda, that adds up fast.
06-19-12, 01:49 AM
#280
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That has to pull so hard, my car pulls the same in 4th as it does in 2nd and I only have a 2 rotor with BNR's. I really am lookin forward to getting your transmission brace looks like a nice piece.
06-19-12, 07:28 AM
#282
Unless your FMIC and radiator are setup like mine, the undertray design I come up with probably will not be very helpful to you.
With the front nose you have I would think that you could be able to adapter a stock plastic under tray. I would need to see under the car to be sure.
With the front nose you have I would think that you could be able to adapter a stock plastic under tray. I would need to see under the car to be sure.
06-19-12, 07:55 AM
#283
Was thinking about trying that but I don't know if it would fit with the Pettit subframe. The Mazmart guys don't think it will work but you never know.
My FMIC and radiator stack is similar in position to yours. I think I am going to try to fab one up out of aluminum sheets and see what happens. Want to also ensure good ducting to the radiator. The big issue for me I think is the FMIC blocks a lot of the air flow as the end caps take up the space on the left and right side of the nose opening. Noticed yours is like that too.
Gotta get the car up on a lift to see what is going on. It's too hard with the car jacked up just a little off the ground.
My FMIC and radiator stack is similar in position to yours. I think I am going to try to fab one up out of aluminum sheets and see what happens. Want to also ensure good ducting to the radiator. The big issue for me I think is the FMIC blocks a lot of the air flow as the end caps take up the space on the left and right side of the nose opening. Noticed yours is like that too.
Gotta get the car up on a lift to see what is going on. It's too hard with the car jacked up just a little off the ground.
06-19-12, 09:38 AM
#284
The stock subframe only has the rear-most mounting points, the majority are actually on the front nose, then 2 bolts on either side on the bottom of the frame rail.
The FEED nose sticks out much further than the 99 spec, which creates a huge gap where the stock under tray makes no contact with the nose. However the opening for the IC is much larger.
If I remember correctly you still have A/C which is another hurdle since it is also blocking air to the radiator. When the A/C is on the condenser throws off a lot of heat directly into the coolant system.
Which radiator do you have?
The FEED nose sticks out much further than the 99 spec, which creates a huge gap where the stock under tray makes no contact with the nose. However the opening for the IC is much larger.
If I remember correctly you still have A/C which is another hurdle since it is also blocking air to the radiator. When the A/C is on the condenser throws off a lot of heat directly into the coolant system.
Which radiator do you have?
06-19-12, 11:19 AM
#287
The stock subframe only has the rear-most mounting points, the majority are actually on the front nose, then 2 bolts on either side on the bottom of the frame rail.
The FEED nose sticks out much further than the 99 spec, which creates a huge gap where the stock under tray makes no contact with the nose. However the opening for the IC is much larger.
If I remember correctly you still have A/C which is another hurdle since it is also blocking air to the radiator. When the A/C is on the condenser throws off a lot of heat directly into the coolant system.
Which radiator do you have?
The FEED nose sticks out much further than the 99 spec, which creates a huge gap where the stock under tray makes no contact with the nose. However the opening for the IC is much larger.
If I remember correctly you still have A/C which is another hurdle since it is also blocking air to the radiator. When the A/C is on the condenser throws off a lot of heat directly into the coolant system.
Which radiator do you have?
We had them build the largest one that would fit into the engine bay. Here are a few shots:
These are old pics and things have been slightly changed but not much. Yes, I do have AC and we have installed two push fans to move the air from the AC condenser and this air then goes directly into the radiator.
I posted this in another thread but I had the Shine 3 piece under tray installed on the car. Testing though showed it raised my water temps by around 7C which is not good. This was in back to back testing in Orlando on a 95F day. Tested without the under tray, installed it, and then repeated the process to ensure what we saw was correct. Temps went up unfortunately.
I'm all for using a 99 spec tray if that would fit and I am open to any and all suggestions on improving air flow with the setup I have. My current plan:
1) Install customer under tray or 99 spec unit and take readings.
2) Install RE-MEDY water pump and measure results.
3) Install 160F thermostat and measure.
4) Modify mesh openings into fender flares per Goodfella thread and take measurements (apparently no one had done this yet).
5) If the above fails, then shell out the bucks to do a v-mount setup. Avoiding this as I don't have the $2,500 needed to make this happen or I might try to use what I have and modify the components to work.
Any thoughts?
06-19-12, 11:34 AM
#288
What water temps are seeing? Also what are your oil temps? When the A/C is on does the water temp ever level out or does it just continue to climb?
If you saw the temps climb with the shine tray, I do not see how installing a different version would yield any different result.
On a side note, I am using the Koyo N-flo which has internal baffles that keep the coolant in the radiator longer allowing the fans to pull more heat out of the water. Forcing the water through the radiator super fast does not give it a chance to cool prior to returning to the engine to be heated again.
If you saw the temps climb with the shine tray, I do not see how installing a different version would yield any different result.
On a side note, I am using the Koyo N-flo which has internal baffles that keep the coolant in the radiator longer allowing the fans to pull more heat out of the water. Forcing the water through the radiator super fast does not give it a chance to cool prior to returning to the engine to be heated again.
06-19-12, 12:20 PM
#289
What water temps are seeing? Also what are your oil temps? When the A/C is on does the water temp ever level out or does it just continue to climb?
If you saw the temps climb with the shine tray, I do not see how installing a different version would yield any different result.
On a side note, I am using the Koyo N-flo which has internal baffles that keep the coolant in the radiator longer allowing the fans to pull more heat out of the water. Forcing the water through the radiator super fast does not give it a chance to cool prior to returning to the engine to be heated again.
If you saw the temps climb with the shine tray, I do not see how installing a different version would yield any different result.
On a side note, I am using the Koyo N-flo which has internal baffles that keep the coolant in the radiator longer allowing the fans to pull more heat out of the water. Forcing the water through the radiator super fast does not give it a chance to cool prior to returning to the engine to be heated again.
Oil temps are usually lower than the water temps by about 5C. I did note recently that they were higher than the water temps but never above 105C. Because this is the first time I noticed them being higher, made a note to check my inline XRP filter (in addition to the normal oil filter) to ensure it's not blocked or in need of cleaning out the filter. My thoughts on this are the temps have gone higher because I[m now in the mountains and doing much more climbing than in flat FL hence the higher oil temps.
I'm with you on the under tray issue but it seems to be counterintuitive to the way things are supposed to work. Had another forum member harp on me for this claiming I can't alter the way aerodynamics work. Yet, the facts are the facts. Thought maybe I could do a better duct and sealing job than what I did with the Shine unit and it would yield better results. Don't really know though.
My radiator is a dual pass unit but I can't remember much more than that. Spec'd it out with Kilo Racing but I need to find the order sheet.
06-19-12, 01:40 PM
#290
Counterintuitive does not make the data wrong. It would take wind tunnel testing to see exactly what is going on. Remember that just because someone is willing to argue does not make them right. I would leave the solid undertray off and just make some sort of mess to protect the radiator. I may test this on our 13b-re Vert which A/C, FMIC, Koyo, OE undertray and typically has 95C water temps.
Honestly, your temps are not far off, maybe a couple degrees up, but nothing to be alarmed by with a car running A/C. We see similar temps on stockish FDs in the summer with A/C engaged. If you were seeing an uncontrolled climb then there would certainly be something wrong. Your water temps are always going to be higher with the A/C on.
Increased load will raise the oil temps. A drastic increase in oil temps will also raise the water temps as the coolant systems tries to compensate.
Honestly, your temps are not far off, maybe a couple degrees up, but nothing to be alarmed by with a car running A/C. We see similar temps on stockish FDs in the summer with A/C engaged. If you were seeing an uncontrolled climb then there would certainly be something wrong. Your water temps are always going to be higher with the A/C on.
Increased load will raise the oil temps. A drastic increase in oil temps will also raise the water temps as the coolant systems tries to compensate.
06-19-12, 02:21 PM
#291
^ Thanks for the input. I appreciate it. What got me on the subject of water temps was my recent track event at VIR where the temps with the AC off got into the 105-108C range before I shut down the runs to prevent anything from happening to the car. This got me worrying enough to try to address lowering the temps.
I concur about the oil temps and believe the increased load of hills has caused the temps to go up. Regarding forum members and their arguments versus the actual testing results, I have learned that facts don't always seem to matter on this forum. To me though, it's all about the results not Wikipedia theory
Thanks again for all the help.
I concur about the oil temps and believe the increased load of hills has caused the temps to go up. Regarding forum members and their arguments versus the actual testing results, I have learned that facts don't always seem to matter on this forum. To me though, it's all about the results not Wikipedia theory
Thanks again for all the help.
06-19-12, 02:31 PM
#292
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^ What fans are you running behind the radiator?
Also, I think the main problem you have (as you mentioned) is the fact you have a FMIC that completely covers up the opening of your bumper. I think you need a freash air duct bypassing the FMIC similar to what Chris Carlisi did to his 3 rotor. Once you do that; then install an undertray.
Edit: Can you independently control the condenser fans? How are those setup to turn on? If they only are triggered by the ac it is possible they are hindering flow even more than just the condenser.
Also, I think the main problem you have (as you mentioned) is the fact you have a FMIC that completely covers up the opening of your bumper. I think you need a freash air duct bypassing the FMIC similar to what Chris Carlisi did to his 3 rotor. Once you do that; then install an undertray.
Edit: Can you independently control the condenser fans? How are those setup to turn on? If they only are triggered by the ac it is possible they are hindering flow even more than just the condenser.
06-19-12, 04:41 PM
#293
Running dual 2750 Cfm fans that come as one unit and in a shroud. Basically covers the radiator opening.
I forgot about Chris and what he did and will go back to look It's been a long time since Chris and bitched about our builds
The ac fans currently are triggered with the ac on switch. Maybe I should wire them up to also come on with the radiator fans. Interesting thought.
I forgot about Chris and what he did and will go back to look It's been a long time since Chris and bitched about our builds
The ac fans currently are triggered with the ac on switch. Maybe I should wire them up to also come on with the radiator fans. Interesting thought.
06-19-12, 04:43 PM
#294
David, depending on what the ambient air temps in VA were that day, those temps may have been normal. We have N/A ITS race cars that constantly see 225F (107C) in summer racing, this is just the normal running temp when the car is spending most of it's time at 9K+ rpm, then once they are off the track the temps come right down to 87C
The A/C condenser is always going to restrict your radiator airflow, and the fact that both of them are behind the FMIC only adds to that. If you plan to compete with a what was obviously built as a street/touring car then I would say set a limit of say 110C and anything over that call it quits until the car cools down. No sense in risking a motor for racing where nothing is to be won besides a cheap trophy.
There is nothing that says you can't build another purpose built race car without A/C
The A/C condenser is always going to restrict your radiator airflow, and the fact that both of them are behind the FMIC only adds to that. If you plan to compete with a what was obviously built as a street/touring car then I would say set a limit of say 110C and anything over that call it quits until the car cools down. No sense in risking a motor for racing where nothing is to be won besides a cheap trophy.
There is nothing that says you can't build another purpose built race car without A/C
06-19-12, 05:01 PM
#295
Chris thanks for all to the assistance and I will stop taking over your thread. I really do appreciate it though. Temps at VIR were below 80 for the morning sessions and in the low mid 80s for the afternoons.
I'd like to drive temps down if I reasonably can so we will see what happens. I hear ya on the track car. I like Fritz Flynn's approach of doing a track specific car versus possibly screwing up an expensive street car. For a newbie track guy like me it was enough to drive, watch the other cars and the flag guys let alone worry about water temps.
I'd like to drive temps down if I reasonably can so we will see what happens. I hear ya on the track car. I like Fritz Flynn's approach of doing a track specific car versus possibly screwing up an expensive street car. For a newbie track guy like me it was enough to drive, watch the other cars and the flag guys let alone worry about water temps.
06-19-12, 11:44 PM
#296
David, judging just by glancing at the above pics it seems that the only fans you have are attached to the a/c condenser. I am willing to bet that if you placed those fans on the other side of the radiator so that they are in direct contact with the radiator, your temps will drop.
Also, sealing the shroud to the radiator should def help as well. If you are worried about the a/c not getting enough air you should seal that to the radiator as well with foam. The stock FD fans shroud completely seal the radiator so ALL the moving air comes through the radiator.
For comparison, my FD w/ a vmount (koyo rad, stock FD fans) NEVER went above 96c in 105+degree weather. This is at a local race track where i was beating the hell out of it. stock r1 oil coolers also.
Also, sealing the shroud to the radiator should def help as well. If you are worried about the a/c not getting enough air you should seal that to the radiator as well with foam. The stock FD fans shroud completely seal the radiator so ALL the moving air comes through the radiator.
For comparison, my FD w/ a vmount (koyo rad, stock FD fans) NEVER went above 96c in 105+degree weather. This is at a local race track where i was beating the hell out of it. stock r1 oil coolers also.
06-20-12, 05:37 AM
#297
Thanks for the advice. I do have another set of fans on the radiator as well. They are 2750 Cfm units and come with a shroud.
I am going to seal everything up better and try to do some ducting as well you have the ultimate setup in a vmoiunt and that might be my best solution here.
I am going to seal everything up better and try to do some ducting as well you have the ultimate setup in a vmoiunt and that might be my best solution here.
06-20-12, 09:26 AM
#298
Are you still running without an undertray / ducting? Also it's my understanding that 105c isn't dangerous or abnormal for a car on the track. 
There is no reason why a properly designed / installed undertray would cause harm cooling. Do you see any other cars running around the track with no undertray? Doubt it. Do you see any of the Rolex GT class cars racing without an undertray? Definitely not. There are multiple reasons for having an undertray, not just cooling (e.g. protecting underside of motor from debris, minimizing drag, aiding in stability at higher speeds).
Without any modification / added ducting to the 3-piece undertray, you'll have two gaping holes on either side of the radiator (depending on where your rad sits) where most of the air will escape (instead of going though your radiator). If you look into the mouth of your bumper and you can see pavement, tires, etc., then your car is not ducted properly.
Below is a photo of the outer pieces from the Shine 3-piece. I don't have a completed photo (and I later revised this setup), but notice how I attached side ducting to the undertray. The center part also has a "lip" attached to it, for where it meets the lower side of the radiator. When all 3 pieces are installed, all of the air entering the main opening of the front bumper is forced though the radiator (with the exception of the scoop for the SMIC). Example (not complete in this photo, just mocking up): http://gallery.tfrascone.net/var/alb...5/DSC_3684.jpg
The goal is to have as much air as possible forced though the radiator. If there are holes anywhere, the air will take the path of least resistance which is around the rad instead of though it. I understand you have an FMIC - you need to have ducting between the FMIC and the rad. The concept is still the same. If you don't have ducting/undertray after the FMIC, all the air going though the FMIC will just go around the rad instead of though it.
What happens to airflow without vs. with an undetray/ducting:
06-20-12, 02:40 PM
#299
That's funny, I recall giving you the same advice recently, and I was told my suggestions were "unwanted". Well, I'm glad you're open to suggestions when other people give you the exact same advice. Hope your cooling issues get sorted out. Not trying to pick fights or say, "I told ya so," but maybe in the future you'll be more open to my suggestions. Good luck w/ the ducting, let us know if it helps.
After finishing the first session when this happened (Friday's afternoon session) I talked it over with Fritz and then called Steve Osley, my mechanic here in Asheville, to discuss. Both agreed that 105C is not ideal and I should get this resolved before beating up the car. Fritz was kind enough to discuss better ducting on the car as well as replacing the front end with something that has larger air intake sections. Steve Osley wants to drill out the thermostat. Dan suggested Evans coolant so I've got a bunch of stuff to think about. I should mention on the way home from the event and with the AC on, we hit around 100C at 80 MPH but when going 60, temps were around 96C so there is definitely opportunity for improvement with high speed air flow.
Guys, don't want to turn this into a undertray thread. Thanks for all of the helpful advice and I will look into fixing the issue. I've never (Theorie) said my car defies the law of aerodynamics so please stop with those remarks as they are unwanted.
As for the constructive advice, very good ideas. As I recall (and it's been a few years) one of my issues with a stock under tray is the Pettit subframe on the car interferes with installing a 99 spec unit. I don't have the time to deal with the issue this week but will get the car over to Steve Osley's so we can jack it up and assess how to fix the problem. I've got some dedicated ducting under there now but clearly not enough and it's not correct. I'll fix this and see what's up then with temps. Now back to the VIR thread.
As for the constructive advice, very good ideas. As I recall (and it's been a few years) one of my issues with a stock under tray is the Pettit subframe on the car interferes with installing a 99 spec unit. I don't have the time to deal with the issue this week but will get the car over to Steve Osley's so we can jack it up and assess how to fix the problem. I've got some dedicated ducting under there now but clearly not enough and it's not correct. I'll fix this and see what's up then with temps. Now back to the VIR thread.
I'm on it and will post up the results soon, just not in this thread as it's Banzai's. Sorry for the continued jack of the thread Chris.