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-   -   Intercooler data logs wanted (https://www.rx7club.com/rotary-car-performance-77/intercooler-data-logs-wanted-1080828/)

diesel dakota 03-26-15 10:33 AM

Intercooler data logs wanted
 
Kind of a long shot as very few people probably have sensors set up for this but its worth asking.

I'm looking for some data logs that include rpm, boost, pre intercooler temp, and post intercooler temp at a minimum. any engine porting would also be useful data to know.

Basically I'm in my last term in chemical engineering and one of my classes has a pretty open ended project. I'm designing a new intercooler type that would operate on some unusual principals. Most likely it either won't work near as good as a traditional intercooler or it will be unreasonably large, either way I need some data from a current system to design and compare against. I would pull some data wit my car but I don't have the time or money to make it happen quickly enough. does anyone have some data lieing around?

evo_koa 03-26-15 10:55 AM

I would contact Howard Coleman, I bet he has that information

diesel dakota 03-28-15 10:53 PM


Originally Posted by evo_koa (Post 11890962)
I would contact Howard Coleman, I bet he has that information

I'll PM him and see if he's got anything

diesel dakota 03-30-15 10:54 AM

Bump

diesel dakota 04-01-15 02:39 PM

Bump again, this project is due in 3 weeks so I'm gonna be hopeful and bump it up a few more times before I move onto another option.

my two other options are find a data log for another vehicle type, which I would rather do my rx7 for as I will find it ore interesting, or to do it for the rx7 theoretically using compressor efficiency's and some correlations to try to estimate what the post turbo/pre intercooler temps would be.

lOOkatme 04-01-15 03:02 PM

Are you sure you can compare data like this?

Heat exhangers are more efficient the lower in elevation and the hotter they run (large delta T). We are up at higher altitudes here and we duct the living hell out of everything and run our intake filters (larger ones at that) and duct nice cold air to the filter, intercooler, radiator, and oil coolers. We have found that the intercooler, size/shape/thickness has less of an impact on air temps than running an air intake to cold air. We run nice large exhausts and intake filters to reduce pressure ratio of the turbo. Outside temps of 20C yield an air temp between 20-25C on the car and sometimes drop below 20C with water/meth (the readings are from two different cars and one is not water injected). Intercooler size on mine is 15 x 10 x 4" thick core, the other is 9" x 7" x 3.5" thick. air temps are the same.


When tuning and railing on the cars the worst we got the air temp was 25C, 5C over ambient. We also noticed during cruise and boost that when we stopped the car and touched the hot side and cold side of the intercooler, both were relatively cool.

diesel dakota 04-01-15 07:28 PM


Originally Posted by lOOkatme (Post 11894541)
Are you sure you can compare data like this?

Heat exhangers are more efficient the lower in elevation and the hotter they run (large delta T). We are up at higher altitudes here and we duct the living hell out of everything and run our intake filters (larger ones at that) and duct nice cold air to the filter, intercooler, radiator, and oil coolers. We have found that the intercooler, size/shape/thickness has less of an impact on air temps than running an air intake to cold air. We run nice large exhausts and intake filters to reduce pressure ratio of the turbo. Outside temps of 20C yield an air temp between 20-25C on the car and sometimes drop below 20C with water/meth (the readings are from two different cars and one is not water injected). Intercooler size on mine is 15 x 10 x 4" thick core, the other is 9" x 7" x 3.5" thick. air temps are the same.


When tuning and railing on the cars the worst we got the air temp was 25C, 5C over ambient. We also noticed during cruise and boost that when we stopped the car and touched the hot side and cold side of the intercooler, both were relatively cool.

If you are running low boost your turbo is generally running at a pretty similar compression ratio as you would at a lower altitude, you will be running at a lower power level though as your engine will see a lower air pressure. As you can see below, 4000ft will result in a 2psia pressure difference to your engine at the same boost level. it does however get worse at higher boost levels.

10psi of boost
at see level atmospheric pressure is 14.7psia, 10 psi of boost would be 24.7psia
lets assume a pressure differential of .5psi across your air filter
your compression ratio is 24.7/14.2 =1.74

lets say your at 4000ft above see level, atmospheric pressure is 12.7psia, 10 psi of boost would be 22.7psia
0.5psi pressure loss
compression ratio is 22.7/12.2=1.86
even at a 0.2 psi pressure loss
22.7/12.5=1.816

high boost
20psi of boost
sea level 14.7psia,-->34.7psia manifold pressure
0.5psi loss
34.7/14.2=2.44

4000ft 12.7psia --> 32.7psia manifold pressure
0.5psi loss
32.7/12.2=2.68

with a higher compression ratio you have a higher temperature increase across the turbo.

it isn't a huge difference but compound that with the fact that the less dense air at high altitudes is also worse at transferring heat across the intercooler and you should need a larger intercooler as compared to a similar situation at lower altitudes.

diesel dakota 04-01-15 07:38 PM


Originally Posted by 427 Doubletree (Post 11894551)
r u serious? he posted up some information where the temperature was totally wrong :blush: i bet the kid would fail his assignment using his supplied information :nod:

I ain't exactly a kid but that's fine I guess I am asking essentially about a homework assignment.
Also I don't get all this Howard hate, you have a person who has put alot of time and thought into trying to help the community and everyone just jumps on small mistakes and tears him apart. I'm sure I haven't agreed with everything he has said but he is trying to contribute to the community. Just the idea of it is ridiculous, "oh look this guy is trying to help advance the community and is generally trying to be nice and helpful, fuck this guy"

I also would be double checking my calculations as this is for a report not an internet forum. if someone gave me data where the intercooler was heating the air or something stupid I would catch it and figure it out. If I was posting info to the forums I wouldn't be checking anything with the same scrutiny and I would be more likely to post something stupid.hopefully if I make a similar mistake hopefully I don't get torn apart in 100's of post across multiple threads.


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