Intake temperature?

[3Sfever]

First off, we probably should agree on "terms", (as mentioned earlier). I would have thought "intake" temps as being at throttle body also.

The temps I will be referring to are the ones reported by ScanMaster, which appears to be at the MAS.

I drove a fairly long circuit this morning. The ambient temps stayed in the low 40's (F) the entire time.

Car was in garage at approx 55 deg when started. Scanmaster reported 55 going out the driveway, so that is encouraging that temp measurement is reasonably accurate. Temps rose to mid-60s and stayed there over the next 10 miles of driving 2-lane highway speeds (and occasional traffic light).

Car sat approx 20 minutes, then was started again. Engine bay was probably more heat soaked now. I forgot to check temps until moving a mile or so, but temps were in mid-80's then, and dropped to low 70's. Stayed there, for 10-15 miles of 2-lane highway driving.

Stopped to get some "fast" food at a drive thru. I did not time it, but seemed like 10 minutes. I remembered to check the temp while waiting for my food at the window, at the end of the wait. --> 103 degrees.

Temps dropped down to mid 80's on rest of trip at highway speeds.

Summary:
K&N filter, no cold wall or hood vent etc.

from cold start:
40 ambient 60s driving = 20 deg diff

after Mild engine bay heat soak:
42 ambient 70s driving = 30 deg diff

Idling for 5-10 minutes:
42 ambient 103 deg = 60 deg diff

after engine bay heat soak:
42 ambient 80's driving = 40 deg diff

[Kibwe Walker]

Originally Posted by 3Sfever

First off, we probably should agree on "terms", (as mentioned earlier). I would have thought "intake" temps as being at throttle body also.

The temps I will be referring to are the ones reported by ScanMaster, which appears to be at the MAS.

I drove a fairly long circuit this morning. The ambient temps stayed in the low 40's (F) the entire time.

Car was in garage at approx 55 deg when started. Scanmaster reported 55 going out the driveway, so that is encouraging that temp measurement is reasonably accurate. Temps rose to mid-60s and stayed there over the next 10 miles of driving 2-lane highway speeds (and occasional traffic light).

Car sat approx 20 minutes, then was started again. Engine bay was probably more heat soaked now. I forgot to check temps until moving a mile or so, but temps were in mid-80's then, and dropped to low 70's. Stayed there, for 10-15 miles of 2-lane highway driving.

Stopped to get some "fast" food at a drive thru. I did not time it, but seemed like 10 minutes. I remembered to check the temp while waiting for my food at the window, at the end of the wait. --> 103 degrees.

Temps dropped down to mid 80's on rest of trip at highway speeds.

Summary:
K&N filter, no cold wall or hood vent etc.

from cold start:
40 ambient 60s driving = 20 deg diff

after Mild engine bay heat soak:
42 ambient 70s driving = 30 deg diff

Idling for 5-10 minutes:
42 ambient 103 deg = 60 deg diff

after engine bay heat soak:
42 ambient 80's driving = 40 deg diff

I see similiar numbers but if you catch a day where it is 70 or more ambient you get 9x on a decent cruise and as high as 13x on slow cruise to stop situations.

[3Sfever]

Originally Posted by Kibwe Walker

I see similiar numbers but if you catch a day where it is 70 or more ambient you get 9x on a decent cruise and as high as 13x on slow cruise to stop situations.

That shows the difference is fairly consistent:
- during cruise --> underhood = 20+ deg higher than ambient
- slow or stopped --> underhood = 60+ deg higher

So when drag racing at track, are we seeing +60 while at the starting line? . . that seems terrible!

Good informational thread.

.

[Kibwe Walker]

Originally Posted by 3Sfever

That shows the difference is fairly consistent:
- during cruise --> underhood = 20+ deg higher than ambient
- slow or stopped --> underhood = 60+ deg higher

So when drag racing at track, are we seeing +60 while at the starting line? . . that seems terrible!

Good informational thread.

.

I am wondering what the summer will reveal since our coolant temps go up with ambient air temp as well.

[3Sfever]

I noticed a couple interesting things on the way home from work.

1) ambient temp was still in 40's, but my MAS temp stayed in the 50's at cruising speeds (instead of 60's and 70's earlier). Change in conditions though -> it was raining. Could rain cause the temperature difference to be in the 10's, instead of 20's or 30's?

2) it is amazing how fast the MAS temp climbs when the car stops. When I got home, I let the car idle a minute or so before shutting off. It was climbing 1 deg every couple seconds. Amazing.

I guess that is understandable, since the underhood temps are naturally going to go up with no fresh air being force in, but it still surprised me how fast.

So where does the cooling flow come from while crusing? Thru cracks around the headlight, up from the bottom?

Wherever it comes from, it is not enough. . . I think I am going to start experimenting with blister mods, and car air walls.

.

[Kibwe Walker]

about the rain yes.

you would be amazed how much whater actually makes its way into the engine bay in the form of mist and we all know about the cooling effects of water as it changes from one form to the next.

2nd part thats it you have a 1st gen rt/tt so your readings should be exactly as mine. Someone with a different front end my have slightly different numbers. Someone with one of these various ram air style or vented hoods should have numbers too and a few of those cold air walls are floating around.

3rd part at idle, the air is coming mainly from the radiator and fans, atleast thats the majority of it. If you cycle through the scanmaster you will see a direct correlation between coolant temp and air temp at idle. At cruise the fans are not on and coolant temp stays 178-182 but at idle you can see 19x's when the fan comes on and the intake temps start going up FAST. One of those vented hoods with a vent right behind the radiator should aleviate that idle temp because the hot air would imediately leave the engine bay and wouldn't make its way over to the MAS.

[Kibwe Walker]

warmed up yesterday

ambient 7x
intake temp in the 10x-12x depending on speed
coolant temp warmer aswell 178-189 depending on how fast I was going

all on a sunny spring day.

[SkortchGT]

I'm pretty sure this is going to be my next hood to replace my stock one:

http://www.aerokits.net/cart/index.p...oducts_id=2447

It's not the best looking, but has enough vents for my liking, and seems like it will get the job done in terms of lowering IAT.

[Kibwe Walker]

Originally Posted by SkortchGT

I'm pretty sure this is going to be my next hood to replace my stock one:

http://www.aerokits.net/cart/index.p...oducts_id=2447

It's not the best looking, but has enough vents for my liking, and seems like it will get the job done in terms of lowering IAT.

The scoote 2 hood looks like it has the most venting available from their list. I wish more people with hoods would post up some numbers because I want to know if venting is as good or better than a 575/stinger/victory/viper which has a scoop to focus outside air over towards the air intake.

With the stock hood on cold to about 50 degrees outside I run 20-30 degrees over ambient, when the ambient temp goes up to about 70 my intake temps go up to about 30-60 over ambient. As it gets warm out it will probably be even worse I suspect.

[jrod]

why dont one of you just take the hood off and drive around? I would but my car is broke.