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Running in Hot weather


Artie

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I recently retrofitted my 89 Turbo with a Chargecooler and 2ndary injectors to basically the SE specs. I've gotten it tuned in and is much faster than it obviously was before the chargecooler. My question is do any of you guys notice a lower power output when it is very hot outside. It has been 100 plus degrees(f) the last few days and the car feels strong until about 5500rpm then feels like the ECM is pulling the timing out. I don't have freescan yet to pull the data but just curious to see what you guys see or feel as the temperature outside rises. I'm still running the older non se ECM in the car and relocated my MAT to the chargecooler elbow, I moved it back to the airbox and it seemed to make a difference, I needed to add fuel as if felt like it was running a little lean(more timing). The power keeps climbing now but wasn't sure what you guys see. Thanks for your input.

Art

89 White Esprit SE

...a few little upgrades....

93 RX7.....Silverstone

....slightly modded...Muahaha...

New Addition:

1990 300ZX TT......Hmmm

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Art,

You cannot get the MAT below the ambient outside air temp. That would break the 1st law of thermodynamics. Density of air is inversely related to temp, lower density means a lesser mass of air in the cylinders to burn the fuel. As a rough rule of thumb you lose 0.5hp for every 1 deg C rise in MAT.

You must be very careful mixing chargecooler and no chargecooler codes and MAT sensor position. One expects the MAT sensor after the turbo the other does not.

Dermot

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I recently retrofitted my 89 Turbo with a Chargecooler and 2ndary injectors to basically the SE specs.  I've gotten it tuned in and is much faster than it obviously was before the chargecooler.  My question is do any of you guys notice a lower power output when it is very hot outside.  It has been 100 plus degrees(f) the last few days and the car feels strong until about 5500rpm then feels like the ECM is pulling the timing out.  I don't have freescan yet to pull the data but just curious to see what you guys see or feel as the temperature outside rises.  I'm still running the older non se ECM in the car and relocated my MAT to the chargecooler elbow, I moved it back to the airbox and it seemed to make a difference, I needed to add fuel as if felt like it was running a little lean(more timing).  The power keeps climbing now but wasn't sure what you guys see.  Thanks for your input.

Art

<{POST_SNAPBACK}>

Art,

did you say you relocated the MAT-sensor into the after-c/cooler-elbow and you still run on the stock-non-c/cooler-ECU ????

Please forgive me, but what you did is a complete mix-up ! :lol:

The non-c/cooled engines have their MAT-sensor in the air box and the real-after-turbo-temp is calculated inside the ECU using fixed tables. You see the MAT-sensor only sees ambient temp all the time and the ECU-program is doing the math.

What you did now is relocating this sensor after the c/cooler ! At this location you will allways have a higher than ambient temp present. And your stock ECU is additionally doing the fixed-table-correction. You see the pattern !?

If you really like to do a proper setup there is no way around a complete ECU and all the other stuff upgrade to full SE specs.

BTW how are you driving the secondary injectors ????

The stock non-c/cooled ECU and harness does not feature/support these ????

Marcus

Marcus

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Art,

did you say you relocated the MAT-sensor into the after-c/cooler-elbow and you still run on the stock-non-c/cooler-ECU ????

Please forgive me, but what you did is a complete mix-up !  :lol:

The non-c/cooled engines have their MAT-sensor in the air box and the real-after-turbo-temp is calculated inside the ECU using fixed tables. You see the MAT-sensor only sees ambient temp all the time and the ECU-program is doing the math.

What you did now is relocating this sensor after the c/cooler ! At this location you will allways have a higher than ambient temp present. And your stock ECU is additionally doing the fixed-table-correction. You see the pattern !?

If you really like to do a proper setup there is no way around a complete ECU and all the other stuff upgrade to full SE specs.

BTW how are you driving the secondary injectors ????

The stock non-c/cooled ECU and harness does not feature/support these ????

Marcus

<{POST_SNAPBACK}>

Thanks for the response guys,

I am quite familiar with these laws, I was just wanting a more "feel" type response. Do you feel that your car is more sluggish in high temps? I'm assuming so as the rules say that you do. Thanks though, I was initially going to set the car up to full SE spec, I have the ECM and connectors but got gun shy when I realized that I would have to depin the old connector and put new pins on the wires, then to find out that Lotus didn't have a very good standardized wiring colorscheme. Anyway this is why I located the MAT in the CCooler. After getting the car running I started to think about the mix up with the ECM having the MAT in the airbox. I kind of left it as it was in the CCooler because the car was running very well, until it got HOT. It still ran well but I could feel the power flatten off as I posted previously. I did put the MAT back in the airbox and adjusted the fuel up a few percent and she pulled much harder than previously.

Marcus,

Thanks also for your input, this is what I suspected. I'm not so concerned about whether the car is an SE or not I wanted more power as the car deserved more than a Mustang! I am controlling the secondary WC injectors with an HKS III additional injector controller. Not sure if you are familiar with them but it is an electonic driver that can control up to 8 additional injectors. It has fine adjustment capabilities and also capable to run with 3,4,6 and 8 cylinder engines. I have used them before on many cars, mostly Japanese tuner type cars(notice my RX7 in my avatar and sig.). I am sending my ECM chip to John at WC engineering next week for a reflash of the memcal since I understand the timing maps are quite conservative. He will also reset the water temp parameters and some other items he feels will help. I have done plenty of research mostly with John at WC about my conversion and I followed his instruction. Although I am thinking that my original plan to put the SE ECM was when I relocated the MAT to the CCooler elbow and just didn't ask if it best to move it back. My assumption when it started to get hot outside was even though my chargecooler was working well, the temps rose faster than the ECM was set for, it would be unusual for ambient temps to rise 20 or 30 degrees F in a few seconds so I started to realize that this must have caused the ECM to pull lots of timing when the temp rose. I put the MAT back by the airbox figuring that the ECM could adjust appropriately considering I now have a chargecooler (denser air) and much more fuel. Also that I would get overboost periodically with the old turbo only setup to 12psi for periods(a few days). Thoughts?

Artie

89 White Esprit SE

...a few little upgrades....

93 RX7.....Silverstone

....slightly modded...Muahaha...

New Addition:

1990 300ZX TT......Hmmm

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Almost all turbocharged cars will feel slower when it is hot outside. Total timing will be lowered, as well as total boost due to the knock sensor. Probably what is happening is the car is knocking and the ECU is pulling timing. (Easily checked with Freescan) Where the MAT sensor is placed probably affects what the location the ECU is getting its data from the fueling tables.

It sounds like a memcal reflash would cure some of these problems.

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Almost all turbocharged cars will feel slower when it is hot outside. Total timing will be lowered, as well as total boost due to the knock sensor. Probably what is happening is the car is knocking and the ECU is pulling timing. (Easily checked with Freescan) Where the MAT sensor is placed probably affects what the location the ECU is getting its data from the fueling tables.

It sounds like a memcal reflash would cure some of these problems.

<{POST_SNAPBACK}>

Paul,

Thanks, I am familiar with turbo'd cars but unfamiliar with liquid intercooling properties and the ecm with these cars. I am very familiar with air/air intercooled setups as my RX7 uses a HUGE front mounted intercooler and yes it is noticably sluggish when it is very hot, but the ecm adds fuel as a chemical cooling adder. I'm considering adding a methanol/water injection system to help in the hotter weather. I also moved the MAT back to the airbox location and fattened up the secondary injector pulsewidth and smoothed the power out. I haven't heard any pinging or abnormal noises under load, but I think the boost is lower due to the heat of the air entering the system at 100 degrees anyway. I am using a LM1 wide band(lamda) logger to tune the car in so I am seeing 10.8/1 AFR's thru the RPM band(I'm using 11.1 as an absolute maximum afr's. Thanks again for all your input.

Artie

89 White Esprit SE

...a few little upgrades....

93 RX7.....Silverstone

....slightly modded...Muahaha...

New Addition:

1990 300ZX TT......Hmmm

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We had 34 Deg Celsius in Germanby today, tomorrow 37 !!!! Today she felt somewhat easier, but not slower. Anyhow, as I now have my notebook permanently hooked up, to see how MAT is doing, I will record data for the next few runs. We will see how ambient temperature affects the data.

After tomorrow I probably will have no car to come home in, as it will be stuck in the asphalt at the last set of lights. :)

Olaf S400 project www.esprits4.de

__________________________________

shapeimage_1.jpg

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We had 34 Deg Celsius in Germanby today, tomorrow 37 !!!! Today she felt somewhat easier, but not slower. Anyhow, as I now have my notebook permanently hooked up, to see how MAT is doing, I will record data for the next few runs. We will see how ambient temperature affects the data.

After tomorrow I probably will have no car to come home in, as it will be stuck in the asphalt at the last set of lights. :)

<{POST_SNAPBACK}>

Yeah, tell me about it! Yesterday it was 102F and 94% relative humidity. Heat index was 115F(the air is very wet). I also have trouble gauging what the power should feel like as my RX7 is a rocket and the power feels like electric propulsion, smooth and linear, whereas the power in the Esprit is much more abrupt at 3K rpm and climbs to a seeming peak at 6K rpm then the boost levels off and back down about .1kg from .9 to .8(probably due to the heat and humidity).

Artie

89 White Esprit SE

...a few little upgrades....

93 RX7.....Silverstone

....slightly modded...Muahaha...

New Addition:

1990 300ZX TT......Hmmm

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I tried uploding the files of today and yesterday, but I only have 21K global upload left ??!!??.

Anyway, today we had about 36-38 Deg Celcius, tendency going up, and she felt the same as yesterday. Looking at the data, from what I could tell, only the MAT went way off due to Turbo efficency defficency.

I do not really tghink that the temperature differences ( 0,5hp per 1 Deg Cel. according to Dermot) could really be noticed. I believe that once a temperature sensor, no matter where in the car, goes a little off the ecu misinterprets and gives wrong boos or fueling.

I still believe, as I still have the ABS spirit haunt me, ( My ABS TellTale goes off after the car was started in warmed up condition) that any wrong signal disturbs the ecu and makes the car feel really funny and off line.

I may as well try to exchange all temperature and pressure sensors in the darn system.

:)

Olaf S400 project www.esprits4.de

__________________________________

shapeimage_1.jpg

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I tried uploding the files of today and yesterday, but I only have 21K global upload left ??!!??.

Anyway, today we had about 36-38 Deg Celcius, tendency going up, and she felt the same as yesterday. Looking at the data, from what I could tell, only the MAT went way off due to Turbo efficency defficency.

I do not really tghink that the temperature differences ( 0,5hp per 1 Deg Cel. according to Dermot) could really be noticed. I believe that once a temperature sensor, no matter where in the car, goes a little off the ecu misinterprets and gives wrong boos or fueling.

I still believe, as I still have the ABS spirit haunt me, ( My ABS TellTale goes off after the car was started in warmed up condition) that any wrong signal disturbs the ecu and makes the car feel really funny and off line.

I may as well try to exchange all temperature and pressure sensors in the darn system.

:)

<{POST_SNAPBACK}>

I am assuming the mat in the elbow after the chargecooler was just seeing a rapid rise in temp thus pulling lots of timing. Car feels fine now just waiting for my freescan link cable from WC engineering so I can read the logs.

ARt

89 White Esprit SE

...a few little upgrades....

93 RX7.....Silverstone

....slightly modded...Muahaha...

New Addition:

1990 300ZX TT......Hmmm

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I tried uploding the files of today and yesterday, but I only have 21K global upload left ??!!??.

I'm afriad that there is a limit to how much you can upload on here, internet real estate is very expensive.

Try http://www.putfile.com or http://www.yousendit.com perhaps.

88 Esprit NA, 89 Esprit Turbo SE, Evora, Evora S, Evora IPS, Evora S IPS, Evora S IPS SR, Evora 400, Elise S1, Elise S1 111s, Evora GT410 Sport

Evora NA

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