Running Really Hot on the Track, I don't necessarily mean fast |
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Running Really Hot on the Track, I don't necessarily mean fast |
ww914 |
May 10 2014, 03:51 PM
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#41
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914 Convert Group: Members Posts: 435 Joined: 29-September 11 From: Central Coast, CA Member No.: 13,621 Region Association: Central California |
Yesterday at Buttonwillow for our DE, the temperature was not all that hot, but I could only get in 2 laps at race speed before my CHT gauge started hollering at me. Here are the maximum values from yesterday:
Cyl #1 384 degrees Cyl #2 357 degrees Cyl #3 433 degrees Cyl #4 402 degrees I have the alarm set at 400 degrees, so each time it reached that temp, I backed off and let it cool down and finished each session with just a Sunday drive. Here's what I have: My engine is a 2270 built by Original Customs 2 40 DLRAs: 150 main jets 180 air correction jets 34 venturis 9164.2 emulsion tubes 75 idle jets 50 pump jets Both carbs are accurately sync'd and the a/f gauge shows between 13 - 14 all through the progression to WOT The timing is set to about 30 degrees I am running a stock cooling system with the thermostat and flaps working properly. I pulled engine tin to look for obstructions. None. I am running a Sebtrab 8 x 10 oil cooler but my temps are over 220 when pushing it hard. No fans. I am not sure where to go from here: alternate cooling, larger oil cooler, fans? Any suggestions would be appreciated. |
brant |
May 10 2014, 05:23 PM
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#42
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914 Wizard Group: Members Posts: 11,632 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
3 will run hotter.
However I wonder what is going on in that bank. Sometimes you need to adjust the linkage at rpm and not just idle. Fans can be an abstruction at speed. Oil cooler exit is more important than fans on a track car. The timing should be fine but sometimes I've found different readings between different timing guns. So worth double checking as too much timing will create heat Your oil catch tank is also an obstruction to your cooling fan pathway. I like to mount my catch bottle on the rear of the engine bay and put nothing on the front firewall in the path of the air for the fan |
ww914 |
May 10 2014, 07:16 PM
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#43
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914 Convert Group: Members Posts: 435 Joined: 29-September 11 From: Central Coast, CA Member No.: 13,621 Region Association: Central California |
3 will run hotter. However I wonder what is going on in that bank. Sometimes you need to adjust the linkage at rpm and not just idle. Fans can be an abstruction at speed. Oil cooler exit is more important than fans on a track car. The timing should be fine but sometimes I've found different readings between different timing guns. So worth double checking as too much timing will create heat Your oil catch tank is also an obstruction to your cooling fan pathway. I like to mount my catch bottle on the rear of the engine bay and put nothing on the front firewall in the path of the air for the fan My can is right over the fan. Maybe I will move it. |
r_towle |
May 16 2014, 07:19 PM
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#44
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Custom Member Group: Members Posts: 24,585 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
3 will run hotter. However I wonder what is going on in that bank. Sometimes you need to adjust the linkage at rpm and not just idle. Fans can be an abstruction at speed. Oil cooler exit is more important than fans on a track car. The timing should be fine but sometimes I've found different readings between different timing guns. So worth double checking as too much timing will create heat Your oil catch tank is also an obstruction to your cooling fan pathway. I like to mount my catch bottle on the rear of the engine bay and put nothing on the front firewall in the path of the air for the fan My can is right over the fan. Maybe I will move it. Yup, I would move that box to the other side. |
ww914 |
May 18 2014, 02:20 PM
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#45
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914 Convert Group: Members Posts: 435 Joined: 29-September 11 From: Central Coast, CA Member No.: 13,621 Region Association: Central California |
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ww914 |
May 26 2014, 05:24 PM
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#46
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914 Convert Group: Members Posts: 435 Joined: 29-September 11 From: Central Coast, CA Member No.: 13,621 Region Association: Central California |
Update on heating issue. Bottom line, everything was still very hot, even after I installed the NACA duct and hose to the cooler. Hard freeway driving 70 -80 caused the temps to show very hot like before:
#1 max 334 #2 max 307 #3 max 437 #4 max 347 My gauge shows a max temp that can be reset. Oil temp ran between 230 - 250 So, with this I decided to drop the engine and take a look around. First thing I found was an alternator cover inside the impeller. That had to be blocking a lot of needed air. The second thing I found were two broken blades. Probably OK for a stock motor, but not for this one, not the way I drive it. So I have a new impeller coming as well as Chris Foley's external oil cooler setup that eliminates the stock oil cooler and sends all the air to # 3 & 4, none to where the stock cooler was as it will be blocked off. There are a couple others things I will check, valve clearance and timing, but that is it for now. |
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