Awesome, one of my ideas was to do some graph overlays if there was much difference for people to see. Instead of starring at columns of numbers.

:rock:

a lot of people on this forum are suckers for a sweet graph overlay :yum: :tup:

Yeah, I did it for the boosted finished builds and it really showed who was maximizing their build versus just turning up the boost for higher numbers.

I am very interested to see the results for this, although I use the AMS hood.

I would say most vented hood that look similar to the Seibon TS will have similar results. Some hoods have larger vents, which might help more at idle or speed. If I could get people who had other hoods together for a weekend, I would honestly consider testing them all. Slap on an OEM hood for a baseline and then the aftermarket hood and repeat tests.

infrared thermometer is what you were thinking, i picked up the harbor freight one years ago (yes it still works) and it has a laser pointer that is fun to play with and it reads within about 5 deg depending. IR thermometers don't like shiny or transparent materials tho. tried to measure the temp of a chromed friction roller at work and i know it it was second degree burns hot but gun said it was 81 degrees (the $750 company one said it was 83.6) and it only cost me $35 on sale.

First log done last week, just got around to editing it.
Also, the fat wavy line on the oil temp is because my temps have been 'bouncing' around lately. I originally thought it was the gauge going bad but the OBD2 sensor and uprev both read it this way. I have added a red line above it to show the actual change in oil temp in a more usable readout.

Details
First graph:
-Morning cold start, around 6:00AM
-About a 20 mile drive with little to no traffic, almost all freeway, speed kept above 70MPH
-Ambient temps were between 80-86 degrees
-The point where the rad fans kick on is when I was exiting off a freeway, sat in a right turn lane for 2-3 minutes and then got back onto another freeway

Peak numbers:
-Engine oil 192°F
-Fuel temp 95°F
-Intake temp 95°F
-Coolant temp 210°F

Engine off numbers:
-Engine oil 190°F
-Fuel temp 95°F
-Intake temp 90°F
-Coolant temp 203°F



Second graph:
-This is after a 10 minute idle with the engine shut off from the above drive
-Followed by a short 3-4 minute drive to see how the engine will cool off
-Speed kept under 30mph

Engine on numbers:
-Engine oil 172°F
-Fuel temp 97°F
-Intake temp 120°
-Coolant temp 208°

Lowest numbers:
-Engine oil 160°F
-Fuel temp 97°F
-Intake temp 118°F
-Coolant temp 203°F

This is the stock hood graphs, right?

More data is always useful, but I think the most important differential is going to be coolant temps. If the hood vents are working correctly, airflow through the radiator should increase substantially (both stopped with rad fans on, and especially at cruising speeds) from the pressure relief behind the fans, and that should in turn show up in the coolant temp graphs pretty noticeably.

Knowing how good flow affects everything else related to bay heat and all that would be nice, but if the coolant temp drops you know you're moving things in the right direction and the rest is just details.

Sorry yes, this is all OEM hood for right now. I have the Seibon TS hood, but waiting to paint & install it for now.

My curiosity is pegged on the drive in 95+ degree weather for 20-30 minutes and then shut it down and idle for 10 minutes and then check the temps. This happens to me a lot, drive around, go into a store and come back out, water temps will go from 205 to 225 while just sitting for a bit.

maybe since theres no air moving thru the radiator then the water/antifreeze in it is just soaking up the heat from the radiators metal..... maybe?:confused:

Is this with making no changes at all to fan profile? Just curious.

I'm playing with my fan tables to try and min/max coolant an oil temps. Mostly, I don't want too much fan keeping the oil from coming up to temp (and keeping me in the 'cold' fuel tables) and I don't want too little so that coolant doesn't get enough flow... yeehaw.

That is what I am assuming is happening, my hope is with an open hood design we see the ambient temps are able to drop around the engine allow some air flow even while the car is sitting.
This will allow hotter air to get away from the car and bring fresh/cooler air to the radiator keeping temps down without creating heat soak.

I am not 100% sure on that answer unfortunately, Sam has told me my tables were modified but my tune is from 2010 when my SC was installed and the fan controls were not open until 2011/2012. Also I do not have a copy of my tune to review, so my hope is when I get a retune in early Sept we can review my current tune and see what was done or not done.

The coolant temp sensor isn't in the radiator.

More than likely, it's the block heating the water while it sits.

Matt, when you let it sit like that, try this:

1) Start engine, let it idle for 10 seconds or so (assuming oil is hot)
2) Note water temp
3) Rev the engine freely to 4K 3 or 4 times.
4) Note water temp

You should see a sharp drop in the reported water temp after just revving it a few times (spinning up the water pump).

Seems to me that in the VQ platform (or at least, the HR and VHR versions) they learned their lessons from the older engines (RB, VG and SR) and made the water pump a low-flow per RPM design with only 5 or 6 vanes on the wheel. This means you have to put some revs on the engine to get the water to circulate fast enough to see an accurate water temp, but also means it doesn't cavitate at high RPM.

For example of the design differences I mean:

OEM RB water pump:

N1 RB water pump:


I know this is a bit off topic, but it's something I've done some research in to literally in the last two weeks, so I thought I'd share.