That's alot of air flow.
Bench racing: Heat Exchanger VS. Pulley/Tune for first mod.
- Thread starter finally03gt
- Start date
That's what I'm saying... and with 2... I'm not even sure the core is efficient enough to make use of that much air, but sure can't hurt. If they'll mount. 99SSls1 said he had one smaller fan and it was a tight fit. If this thing will fit, I believe it would get everything possible out of the stock HE.
I got the first 8 inch fan installed the way I want it but I had to remove the crossbar that the pump mounts on. I left enough for the pump to set on for now and will have to remove it totally to get another fan in there. (Deal with that when the other fan gets here). Took me about an hour to remove the bumper cut the crossbar and install the fan and wiring. Bumper is still in the yard so maybe another 20 mins in it. I took some pics I will upload later for you.
Well get some data with out the fans and some with the one fan. Normal driving iat2 temps.
AWSOME 
op:
oh, and 99 SSls1 and I have also been using this thread, so I'm going to cross post them.
http://www.svtperformance.com/forums/showthread.php?963807-Another-Heat-Exchanger-Question/page2
op:oh, and 99 SSls1 and I have also been using this thread, so I'm going to cross post them.
http://www.svtperformance.com/forums/showthread.php?963807-Another-Heat-Exchanger-Question/page2
Did a log with no bumper in my garage. I let it run with the ac on for 30 mins then I turned the new fan on. Ambient was 84 in the garage with a engine temp of 176 and iat2 of 139 max and it seemed to peak. I ran the fan for 10 mins and it dropped the temp down 127, we are having a party tonight so I had to cut it off. I'll do some more logs tomorrow on the road. More to come.
Still a little warm, but that's idling in a garage and working from already being hot. What I've read, tunes bump the IAT up to 120°-130° before timing starts to pull, so that would lead me to believe that's generally accepted as a safe temp for detonation. Obviously cooler is better (cool air = denser = more fuel = more power) but seems like if it would stay under 120°, that would be a good start.
With the above post in mind, I dug thru the forums to look for real world AIT's. Hard to find. I know ambient temp is hugely variable, and traffice/hwy/hot lap/drag passes plays a big part, but few ppl talking about actual numbers. Just my car ran cooler, or my car pulled timing again. I did find one with guy running a KC bragging about AIT around 100° during mulitple 1/4 passes.
Any HE guru's wanna chime in on what AIT's to shoot for, or what's acceptable?
Any HE guru's wanna chime in on what AIT's to shoot for, or what's acceptable?
I always suggest cooling first. About 20 percent take that advice. There's zero sense in spending money on power that will be zapped by high downstream temps.
Still pretty new here, but I'm picking up on many threads, that if it comes from you, it's probably legit. Thanks for the input
Any ideas on target AIT's?
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I agree cooling is good but half the people don't need the "race car" parts for there car as I don't. My day in day out with many wot runs and just playing, I have never seen a logged temp over 140. That is running with one fan on my he. Sure maybe if I went to the track It may but I haven't been there yet. I did stop start my car after running my test in the garage and temps went up to 151 from having the engine off. After starting it took about 1 min to get back down to the mid 120's. Raining today so a test won't be accurate info. I guess if you want the best of the best the triple sounds like it but do you need if you don't race. For my situation I don't feel the need.
I want to put it to rest and put dual fans on my stock he. I was going to stop with one fan or even just double stack with another stock he b/c they can be had for 100 here local. We will see what the stock he can do here next week.
I want to put it to rest and put dual fans on my stock he. I was going to stop with one fan or even just double stack with another stock he b/c they can be had for 100 here local. We will see what the stock he can do here next week.
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Found a thread that actually talks IAT numbers...
http://www.svtperformance.com/forums/showthread.php?1025643-Normal-IAT2-with-C-amp-R-Hear-X
http://www.svtperformance.com/forums/showthread.php?1025643-Normal-IAT2-with-C-amp-R-Hear-X
I caught that one, good info.
Did u install a "pusher"or "puller" fan??
What yr is your car?
What yr is your car?
With a stock heat exchanger, you'll see IAT2's of 160+ on a warm day and beating on it a little. The stock calibration begins pulling timing as low as 110f downstream (think: sitting in your driveway, idling for a minute or so). Take a look at this table. Now, imagine what's happening to your power when you're at 160+!!
I use the AFCO dual pass/dual fan unit and have for a good number of years. I can make a pass at the track, pull into the pits and turn everything off. Within minutes, the IAT2 is at 170+ because it's just sitting there baking in its own heat.
Turn on the pump and fans and it's down to 125 or so in about a minute. 120-125 (ish) is a normal number for a car on a hot day. When you have auxiliary cooling, we can adjust this table so you don't pull ANY timing until later (higher temp than 120 but still retaining the safety factor of pulling it at temps much higher than that).
Our VMP triple pass/11" fan is frankly overkill for me. If I were road racing, I'd use it because of the continuous workload and other cars interrupting airflow. But, for my daily driver/dragstrip car, the AFCO is fine.
BTW, we installed a GEN II TVS for a customer at Mustang Week and he took it to the track that night. When I saw his trap speed (which was off by about 5-6 mph from where he SHOULD have been at that power level) I told him we'd datalog and take a look. Yup, he was 160+ after just driving it to Myrtle Beach (open air, 70mph...should have been fine for cooling, right?)
I showed him the table I'm sharing with you and needless to say, a heat exchanger is now on his hit list.
Let me know if I can help you any further, but when you look at this, you'll see exactly why cooling is critical. Oh...and this shouldn't be an afterthought, but of perhaps even more importance.....heat contributes to detonation. Enough said.
bj
Is the "-150" mean 15deg. Of timing retarded??
No. You need two pieces of information here:
This table, and the Spark Retard ACT multiplier table.
Take the output of both, multiply them, and that gives you the amount of spark...in degrees....that gets pulled at X downstream temp.
For example, let's say that the multiplier at X "load" and X rpm is 0.10 and let's use this 150 degree temp as our downstream. Take the -50 number and multiply it times the "multiplier". -50 times 0.10= -5 (the negative sum here is minus 5 degrees of spark advance)
Let's use 17* of total advance at wot as our baseline. Once your IAT2 reaches 150f, you've now lost 5 degrees of timing and you're ow at 12*; a loss of about 30% of your spark advance. Imagine what that does to power.
Anyone need a nice, shiny new heat exchanger? I have them for sale
vmptuning.com
No. You need two pieces of information here:
This table, and the Spark Retard ACT multiplier table.
Take the output of both, multiply them, and that gives you the amount of spark...in degrees....that gets pulled at X downstream temp.
For example, let's say that the multiplier at X "load" and X rpm is 0.10 and let's use this 150 degree temp as our downstream. Take the -50 number and multiply it times the "multiplier". -50 times 0.10= -5 (the negative sum here is minus 5 degrees of spark advance)
Let's use 17* of total advance at wot as our baseline. Once your IAT2 reaches 150f, you've now lost 5 degrees of timing and you're ow at 12*; a loss of about 30% of your spark advance. Imagine what that does to power.
Anyone need a nice, shiny new heat exchanger? I have them for sale
vmptuning.com
You by far have more say on this then I ever will. Can we compare a stock he 11-12 and 13/14 to a large unit with two honking fans running, hell no. Now with fans installed the gap that I am seeing is not as big as many people would think. Also we are comparing the 23 x 6 x 2 1/16 core from the 11-12 not the 07-10 core which is smaller. Thank you the timing table.
My car is a 11 and I installed one puller right now.
These are the pics of the first fan install. If I went any smaller then a 8" fan the cfm's dropped a ton so i just let it go about an inch over the top and bottom.
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Keep in mind that if you're in traffic (road or track) or standing still, you've got nothing going over the fins/core in a non-fanned unit.
bj
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