hood popped - Page 3 - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


General Miata Chat A place to talk about anything Miata

Closed Thread
 
 
 
LinkBack Thread Tools
Old 07-17-2010, 11:41 AM   #41
Elite Member
iTrader: (18)
 
Join Date: Dec 2007
Location: oahu
Posts: 1,720
Total Cats: 2
Default

I can't believe you guys! The op has a great idea.

That being said flounder please execute operation "cool my engine via. partly popped hood" and post your findings. Before and after pics would be nice also.
astroboy is offline  
Old 07-17-2010, 11:43 AM   #42
Elite Member
Thread Starter
 
Join Date: Mar 2010
Location: Detroit
Posts: 1,524
Total Cats: 27
Default

Quote:
Originally Posted by leatherface24 View Post
Pop the hood. While youre at it, another trick to lower compression and cool everything down at the same time us jb welding pennies to the top if your pistons. Ask joe perez. He can further edjucate you on this
Your way off man, silver dollars are where it's at. Only douchebags use pennies.
flounder is offline  
Old 07-17-2010, 12:12 PM   #43
Elite Member
iTrader: (2)
 
fooger03's Avatar
 
Join Date: Jan 2009
Location: Columbus, OH
Posts: 4,132
Total Cats: 187
Default

underhood temps != coolant temps

pop your hood and your underhood temps may go down while your engine/coolant temps go up

Better solution - search through build threads for:
1. Heat shielding on the turbo
2. Isolating/sealing the intake filter from the rest of the engine to form a 'cold air intake' of sorts

And unless you want to project the image of civics and integras running around with poorly made bodykits in gray primer that flap like wings where the bumpers form the wheel wells, and the right door smashed in and you can tell hasnt been fixed in years because of the rust, mismatched 'euro' style taillights, running on 19x5" wheels, and with a obnoxiously loud fart can exhaust that goes from 'weed eater' to 'chainsaw' when you step on the gas, all while a massive black sheen covers your rear bumper because you just decided to run super rich instead of tune the car properly....then close your damn hood, riceboy.
fooger03 is offline  
Old 07-17-2010, 12:50 PM   #44
Elite Member
Thread Starter
 
Join Date: Mar 2010
Location: Detroit
Posts: 1,524
Total Cats: 27
Default

Quote:
Originally Posted by fooger03 View Post
underhood temps != coolant temps

pop your hood and your underhood temps may go down while your engine/coolant temps go up

Better solution - search through build threads for:
1. Heat shielding on the turbo
2. Isolating/sealing the intake filter from the rest of the engine to form a 'cold air intake' of sorts

And unless you want to project the image of civics and integras running around with poorly made bodykits in gray primer that flap like wings where the bumpers form the wheel wells, and the right door smashed in and you can tell hasnt been fixed in years because of the rust, mismatched 'euro' style taillights, running on 19x5" wheels, and with a obnoxiously loud fart can exhaust that goes from 'weed eater' to 'chainsaw' when you step on the gas, all while a massive black sheen covers your rear bumper because you just decided to run super rich instead of tune the car properly....then close your damn hood, riceboy.
1 and 2 will definitely be on the way. This was only like the 5th time i've actually driven the car since the kit has been installed, thats why i'm running on the rich side. I'm still seeing 14-15 at idle, I just can't get an accurate tune until the wga gets here.

It doesn't even look that bad with it up. Second pic almost looks like some sort of an angry uni-brow.
Attached Thumbnails
hood popped-p_00146.jpg   hood popped-p_00147.jpg  

Last edited by flounder; 07-17-2010 at 01:05 PM.
flounder is offline  
Old 07-17-2010, 12:52 PM   #45
Elite Member
iTrader: (21)
 
Join Date: Jun 2007
Location: Rochester, NY
Posts: 5,684
Total Cats: 555
Default

Hey, your hood isn't latched.
rleete is offline  
Old 07-17-2010, 02:02 PM   #46
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,860
Total Cats: 1,788
Default

Quote:
Originally Posted by flounder View Post
another hour of comparison-

Took it out today along with my digital pyrometer and did some before/after testing with the same route and time frame. Temp outside is sunny and around 85F and running a rich tune of around 10.5-11.00to1, max boost 3-4psi. Timing retarded by 1-3 degrees from 3k-7k and i'm not hearing any knock either way.

Testing after first run with hood closed-
Temp at filter-131f
temp at last bend before TB-155f
temp at turbine-660f
temp at compressor 138f

Testing after second run with hood popped and safety wired-
at filter 113f
at last bend-134f
at turbine-630f
at compressor-122f

I never went over 60mph and my water temp gauge never went past half.

IDK? It seems to work at least a lower speeds, kinda afraid to go any faster with the hood up.

Are you guys seeing temps in the 750's at the collector on the log manifolds? Not used to that.

Cool, so you just proved exactly what everyone else was saying: that popping your hood allows a **** ton more air overtop of the radiator and not through it.

WHO GIVES A **** IF YOUR TURBINE IS 660F OR 630F?!!!!?

YOU WANNA KNOW WHY YOU'RE SCARED YOUR HOOD IS GOING TO FLY UP>?!?! BECAUSE YOU'RE CREATING POSITIVE PRESSURE BEHIND IT, WHICH MEAN LESS AIRFLOW THROUGH RADIATOR!!!!!!!!!!!!!!!!!!!!!!

Do you want me to do the math to show you how much power you gained from the filter temps of 131F to 113F without an intercooler netted you? cause that's the only place you just benefitted, but at the risk of overheating the motor.
Braineack is offline  
Old 07-17-2010, 02:28 PM   #47
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,915
Default

There is only one appropriate response here.

Joe Perez is offline  
Old 07-17-2010, 02:30 PM   #48
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,860
Total Cats: 1,788
Default

Braineack is offline  
Old 07-17-2010, 02:31 PM   #49
Elite Member
Thread Starter
 
Join Date: Mar 2010
Location: Detroit
Posts: 1,524
Total Cats: 27
Default

[QUOTE=Do you want me to do the math to show you how much power you gained from the filter temps of 131F to 113F without an intercooler netted you? cause that's the only place you just benefitted, but at the risk of overheating the motor.[/QUOTE]

Sure, that would be great. 21 degree difference at the tb is what most impressed me.

I understand the good/bad effects of doing this but at the psi i'm running and the fact that this is a weekend car with minimal stop and go driving I really don't feel like it's that big of a deal. I have a temp gauge and I will most def be monitoring it closely during these tests. The second I see anything over half way up the gauge, i'll shut the hood.

"However, it is always useful to get more air flow under hood. It is the incoming air flow that pushes all the hot air out."-Braineak from sticky in diy turbo.
flounder is offline  
Old 07-17-2010, 02:43 PM   #50
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,860
Total Cats: 1,788
Default

Are you intake temperatures actually 23*F cooler...im going with no.


OKAY, Let boost be at 6 psi. The temp gain with turbo is about 14/15F per psi, or about 90F.

On this 90F ambient day, ambient absolute would be 90 + 460 = 550F.

The charge temp absolute would be about 550 + intake delta (131-90=41) + another 90 from the turbo, which comes out to 681F

Density would degrade by 550/681 = .807

The pressure ratio at 6 psi is 1.41.

With the heat from the turbo, then the 141% more density from compression will be degraded by .80 x 1.41, or to about 1.128.

With the hood popped, you saw intake temps drop 18F.

Therefore, the charge temp absolute in this instance would be about 550 + intake delta (113-90=23) + another 90 from the turbo, which comes out to 663F.

Density would degrade by 550/663 = .83

With the heat from the turbo, then the 141% more density from compression will be degraded by .83 x 1.41, or to about 1.17.

With a 90% efficient IC, .90 of the 90F temp rise will be taken out, or about 81F removed, thus leaving a net gain of 9F. This would leave a density loss of only 2% from the heat, or a net gain of 1.41 x .98 = 1.38

Hood down = overall gain of 12%, or 101rwhp
Hood popped = overall gain of 17% or 105rwhp
Intercooler = overall gain of 38% or 124rwhp
Braineack is offline  
Old 07-17-2010, 04:15 PM   #51
Elite Member
Thread Starter
 
Join Date: Mar 2010
Location: Detroit
Posts: 1,524
Total Cats: 27
Default

Thanks braineak. Thats the kind of info i'm looking for. Although I certainly hope i'm seeing better whp than those numbers with the 1.8l boosted?

So, there is something to be gained by allowing cooler air into the engine compartment, that's a given. But there are better/safer ways to achieve that goal than leaving the hood up a tad. I'm all for intercoolers but when I bought the non ic'd bypass pipes I was under the impression that they could be used in conjuction with an intercooler, I don't think that is the case and I already dropped $135 bucks extra to get it so i'm holding off on the IC probably until next season.

If the only negative effect of doing this besides the hood flying up and sending me blindly into oncoming traffic is higher coolant temps, then whats the harm in some trial and error testing while paying attention to the ect sensor?

Thanks Brain.

Now to thread jack myself... I just got back from my first freeway run, with the hood locked btw and although she pulls awesome in 5th from 80 to 100 the car shakes pretty bad. Is that the sweet unbalanced chinacharger i'm feeling? Never felt it in city driving?

Last edited by flounder; 07-17-2010 at 05:46 PM.
flounder is offline  
Old 07-17-2010, 04:55 PM   #52
Elite Member
iTrader: (18)
 
Join Date: Dec 2007
Location: oahu
Posts: 1,720
Total Cats: 2
Default

If your hood flew up you can see under it so no blind driving needed. I recommend for about $40 you:

-Shut your hood all the way
-Seal around your radiator/make some ducting
-drain your coolant and fill it with distilled water and some antifreeze
-buy some sheet metal and make a heat shield

Or for about $250 you:
-buy an intercooler, piping, and fab up something that doesn't suck...you could even (try to) sell your pipes to cut the price down even more

Or add a 5th injector...I agree your turbo is making your car shake. Better get that **** balanced.
astroboy is offline  
Old 07-17-2010, 05:14 PM   #53
Tour de Franzia
iTrader: (6)
 
hustler's Avatar
 
Join Date: Jun 2006
Location: Republic of Dallas
Posts: 29,114
Total Cats: 351
Default

Quote:
Originally Posted by flounder View Post
Now to thread jack myself... I just got back from my first freeway run, with the hood locked btw and although she pulls awesome in 5th from 80 to 100 the car shakes pretty bad. Is that the sweet unbalanced chinacharger i'm feeling? Never felt it in city driving?
lol, I bet you have severe detonation.
hustler is offline  
Old 07-17-2010, 05:44 PM   #54
Elite Member
Thread Starter
 
Join Date: Mar 2010
Location: Detroit
Posts: 1,524
Total Cats: 27
Default

Quote:
Originally Posted by hustler View Post
lol, I bet you have severe detonation.
Yeah, that's hilarious hustler. AFR was looking good although a tad rich and I can't hear **** for knock even with the windows up. Plus, i have a knock sensor thats hopefully doing it's job.

It is hot as **** out today, i'll wait until it cools down and do another freeway run to compare.
flounder is offline  
Old 07-17-2010, 06:11 PM   #55
Tour de Franzia
iTrader: (6)
 
hustler's Avatar
 
Join Date: Jun 2006
Location: Republic of Dallas
Posts: 29,114
Total Cats: 351
Default

Just because its fat doesn't mean you're free from detonation. That knock sensor doesn't do a god damn thing. Apologize to me for your shitty attitude and I might look at your spark table and tell you what's wrong.
hustler is offline  
Old 07-17-2010, 06:41 PM   #56
Elite Member
iTrader: (1)
 
NA6C-Guy's Avatar
 
Join Date: Feb 2008
Location: Birmingham Alabama
Posts: 8,038
Total Cats: 43
Default

This thread makes me want to club baby seals... with dead babies.
NA6C-Guy is offline  
Old 07-17-2010, 06:43 PM   #57
Elite Member
Thread Starter
 
Join Date: Mar 2010
Location: Detroit
Posts: 1,524
Total Cats: 27
Default

Have at it chief. My attitude isn't shitty, I happen to be a very easy going individual with a great deal of patience for people. If you look at most of my threads, the fireworks are usually coming from others.

background on car. 99 with stock pump and injectors running emb. Seeing around 75-80% DC max with that fuel table and under boost i'm seeing afr's in the mid 10's-mid 11's.
Attached Thumbnails
hood popped-maps.jpg  
flounder is offline  
Old 07-17-2010, 07:15 PM   #58
Tour de Franzia
iTrader: (6)
 
hustler's Avatar
 
Join Date: Jun 2006
Location: Republic of Dallas
Posts: 29,114
Total Cats: 351
Default

No apology, no assistance.
hustler is offline  
Old 07-18-2010, 05:03 PM   #59
Senior Member
iTrader: (9)
 
Join Date: Oct 2006
Location: Lexington SC
Posts: 1,003
Total Cats: 14
Default

Just because you are pushing out all the hot air out of the engine compartment doesn't mean a thing for coolant temps. You need airflow through the radiator. To get that airflow you need a pressure differential. IE High pressure in front of rad and low pressure behind hit (relatively that is). The air in front is at a higher pressure due to being collercted at the pressure center at the front of tha car and the air passing the underside of the engine compartment creates a lower pressure zone (thats why you see a difference with or without the belly pan) that creates your differential pressure accross the rad. Now when you push in the higher pressure air into the engine compartment with propped hoods, scoops, or teh raised rear hinge mods you will move air through the engine compartment and lower temps in there a little but greatly reduce the effeciency of the radiator or intercooler or anything that you are trying to suck air through at the front of the engine compartment.
Simply keep your flow through the radiator.

You are doing the right thing by taking measurements and trying to study stuff. Just make sure you really understand what you are looking for.

On a different note. Don't screw with a hood that is not propperly latched! On my first car I had just spent a load of cash redoing the head gasket when on the first test drive at 30 mph, BOOM! The hood flies up, cracks my windhield in three places, bends up the hood and all kinds of sheetmetal as wheel. It was pushed down and I thought it was latched. So, in short, DON'T screw with it.
Rallas is offline  
Old 07-18-2010, 06:08 PM   #60
Senior Member
iTrader: (14)
 
Join Date: Aug 2008
Location: Tinley Park, IL
Posts: 1,488
Total Cats: 0
Default

Your are a certifiable ******* idiot. If you want lower coolant temps, follow the advice given above. If you want cooler air temps, install a fresh air intake. You wouldn't put a cast on your arm to fix a broken leg would you? You ******* dumbass.

And Christ almighty quit with the popped hood ****.
lordrigamus is offline  
 
 
Closed Thread

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 58 Yesterday 10:04 PM
1991 special edition with hard top full part out JC, NJ russian Miata parts for sale/trade 6 10-08-2015 04:01 PM
Expected intake temps on the track? tazswing Race Prep 20 10-03-2015 12:04 PM
WTB parts for HPDE car Voltwings WTB 5 09-11-2015 09:23 AM


Tags
how do they work

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 12:41 AM.