I just read this this on Icon Motorsports' section on building LO3's. They talked about the stock intake being like a person running a marathon breathing through a straw. I agree with that. But then they recommend the dual snorkle. They say that an open element is worse for making power because all it does is make the motor take in hot air. I am not putting ram air on my RS. What do you all think? I do not want to spend hundreds on a dual snorkle that in my opinion, looks like complete sh*t, when I can have a nice chrome open element. Anyone have dyno's to prove that open elements work?

 

Just take that little rubber strip on the back of your hood loose and that should put in a good bit of cooler air kinda like a cowl hood. Since having the open element on mine I have had nothing but an improvement.

 

I agree for $40 you can buy a variety of different brand open elements and they are great. Honestly I think for a bolt on it is the best bang for the buck. I agree that it sucks in warmer air but I just left the stock intake tube on and it helps fresh air get to the open element.

 

if you remove rubber strip on the back of the hood , don't throw it away . you may want to put it back on . if you do much stop & go in traffic with a/c on you will pull eng fumes into car . good luck .

 

There is no need to remove it and get water and dirt in the engine bay... Just leave the stock intake tube on and it will blow cold air right on the open element.

 

i put a flow through top on it and a taller filter. but i also have a 4 inch cowl and it sucks air through that.

 

I am commuting to Sun Prairie, WI for college starting this Fall five days a week for the next three years, and that's about a 40 minute, 35 mile drive each way. So I take my baby to college and back Spring-Fall. I go right through Madison, and sometimes traffic gets bad... I think I'll keep that seal on there!

Anyone know where I can get one of those stock intake tubes? I bought my car last fall and it didn't have one. Last owner must have removed it.

 

What kind of improvement are we talking about? 5hp? Less? Is there any kind of noticeable change while driving it?

 

It will allow it to breath better so will help you get more Hp out of other mods. Tbi mods + Open Air should get you better throttle response, a mpg or so, and some power, how much ? depends on what mods are done.

 

Look for the tube @ the junk yard. As for the power gains, I have no solid #'s but with a k&n filter, the tube, & the rubber gone from the fire wall you should see at least 15-20 hp. The f/w rubber also helps to get rid of under hood hot air. Dont worry about water or dirt getting in its not that much. Just make sure you seal any holes in the fire wall so water does not get in the car. The dirt is just not going to get in since its on the top of the car unless you drive gravel roads.

 

just for the record, cooler air means less mpg. The hotter the Qh and the lower the Ql, the higher the effeciency.

 

Thats not true. cooler air burns easier and better. so therefore better mpg and more power. but with more power ppl go faster and they take the mpg increase away. but dont drive like a maniac and you'll see an improvement.

 

When I switched to my open element I really can't say how much power was gained but it was enough to feel in the seat. To me it really seemed like the acceleration picked up.

 

You will really feel it, if you mod your TBI unit, and put on a open element.

Only time i take mine off, "cept for repairs" is for smog, put the stocker back on, and you can feel it choke the engine.

 

Okay, next question. I drive my car until the roads get salted. I need it to start everyday. My car is missing that tube from the engine to the intake that helps feed warmer air into the motor. Lol, driving this car when it's under 10 degrees is frustrating, the thing acts like a Camaro with Down's Syndrome, and it is very very sluggish until it's been on the road for about 10 minutes. Is an open element going to make this winter thing worse?

 

I'm going to be very excited, I'm getting the lifter fixed, correct EFI dizzy put on, headers, open element, tbi mods, intake manifold, a 3.73 rear end and a burned chip this year (fingers crossed). My ill-timed 14 second 0-60 Camaro is gonna be haulin' ***!!!

Looking for 200+hp, 300+ft. lbs. torque.

 

actually, theorettically efficiency (which also translates to how much of the stored chemical energy of the gas is actually used) increases as the Q(h) increases and the q(l) decreases. It's also used by GM. They have stock cooling (thermostat, fan, etc) that don't engage by stock until the engine has heated up. They do this for efficiency.

 

Well, hate to brake it to you, but you're wrong.

The Combined gas law is applied here. It is based on Boyles law, Charles law, & Gay-Lussacs law. http://en.wikipedia.org/wiki/Combined_gas_law

It states that the density of air will change directly in relation to air temperature at a given pressure & volume.

When the engine sucks in 1cf of 150F air at 14.7psi, the density of the air will be less than that of 1cf of 80F air at 14.7psi.

Now how does this affect efficiency? If the engine supplies more fuel than the air can burn, it will be rich and you'll be wasting gas. However, if the engine has more air than the fuel can burn, you run lean and lose power. So in order to run the engine at max efficiency you have to have an air charge that is cool enough to supply the required amount of air for combustion, yet warm enough to not run the engine lean. Also, hot air has the distinct disadvantage of causing detonation. Why do you think they run intercoolers on FI? To cool down the air charge so they can get more air in the cylinder and prevent detonation.

 

I think you have things crossed on this comment. If the coolant is too cold, & the intake air is cold then you have trouble. If you have the right stat in the car per manufacturers specs the motor will be hot enough. The cold intake air will help make power hands down. If not then I feel sorry for all of us that have bought cold air kits for decades.

 

Probably not as warm air rises, so the heat from your engine will float up and go in. When your moving this wont happen, so start up is not affected. Its good practice to allow the vehicle to warm up before you start driving anyways, that way you dont risk metal fractures, dont pollute to bad "emissions wont be up to par yet" , and it will save the life of your tranny by not putting it in D from park when your car is still humming at 1k+ rpm from being in open loop "correct me if im wrong"

 

power<>fuel economy.

 

Colder intake air does help fuel economy in that it allows the engine to burn the fuel more completely therefore requiring less fuel to generate the required amount of power to continually move at said speed.

 

May be posssible on heavy modded engines. On a stock lo3 it will be closer to 2-3hp.

 

Stock LO3 shows a dyno proven 13hp difference with an open element.

 

It is

 

That's closer to what I was thinking. 2-3 hp Seems more like bs. If you read the ultimate tbi mods, the writer said that the open air filter is the best way to go. If your one that does not understand that, then you should read up. Seems like a good source. If not then everyone that has done the mods must have just waised time, & money. I will stick to what makes since.

 

I do agree the open element is the cheepest and easyest way to go.

2-3hp for an open element on a stock lo3 bs?
Thake 2 good running lo3 thirdgens and race togheter to make sure they run the same, then swap the open element on one and race again.

 

I just removed my open element and put the TPI set up back on. Now I'm back to 24 mpg vs. 21 w/open element. That's a 25 mile commute w/the middle 1/3 of the distance on the highway. The rest is local roads.

 

i know this is off-topic but i need to say this:
Aaron, i see you posting about different mods and boltons all the time across this forum, but you never quite fixed your initial problems. you should not modify an engine that doesn't perform right in the first run. my completely bonestock formula takes about 8 sec for 0-60. something is very very wrong with your setup. i would concentrate on fixing that first, then start with mods.
just my opinion

 

2-3 horsepower, going from a 3" diameter suck hole on the stock to a full open air cleaner? Put the drugs down man.

Now If you advance the timing, new plugs, wires, fuel filter, more open exhaust, and clean out the TBI unit, it wakes the motor up, quite alot, too.

 

We figured it out. When we switched the carb for a tb unit, I didn't think to change the dizzy =/ oops lol. All the issues I'm having is timing related, and as a carb'd car, the timing was always spot on. I'll have it all taken care of soon.

 

 

carcraft did a test with an '86 mustang and dual snorkel cold air setup.

They had three setups, the dual snorkel, cowl hood open-no element, and no element-cowl closed.

they lost 4 mph and added .19 sec to et when they had the open carb sucking hot underhood air. on a 69° ambient temperature day, the air temp entering the carb was 26° hotter at the end of 1/4 mile. hot air no good.
http://www.carcraft.com/techarticles...car/index.html

 

You could get way more out of a open element if you have the right hood. Even adjusting the front of the hood up some, removing the rear seal " keep it for wet season" will allow cool air to flow around that element while pushing the heat out the rear.

 

One of my Chilton's manuals describes the operation of the thermac device. This is for carbureted applications. It says that the reason the thermac is needed is because the carburetor's jetting can not regulate the fuel/oxygen ratio beyond certain air temperatures because the density of oxygen atoms in the air varies. The thermac regulates the air temp to be within a certain range by opening and closing the valve between hot and cold air. If this is the purpose of the thermac, and considering that the TBI systems have one, I have to wonder if the TBI is also restricted to a certain range of air temp operation beyond which it can no longer regulate the fuel/oxygen ratio.
Taking into consideration the Carcraft test I linked to; if the under hood air temps rose 26° on a 69° day after 1/4 mile, what would it raise to on a 100° day after an hour on the freeway? Then is the added heat in the combustion chamber pushing the engine over the detonation threshold? Then is the ECM pulling timing out to prevent knock? Just wondering.

 

Guy's, I have played around with the open element vs stock intake with two identical stock lo3 fbodys. To be exact, stock one (had a cheap Fram cotton filter) vs a 3x14" k&n with the standard drop base. At that time we also had 2 "performance chips". Now what I remember wery well is, 1. Open element would not even get over 1/2 car lengt vs the stock air intake on a aprox 1/6 of mile, 2. Driving a long up-hill mountain road with the open element, at certain point my car could just not keep up, not that he was much faster but clearly pulling away. 3. A gray Audi rs station-wagon clearly humiliated both our cars, I did not even have time to read wich one it was exactly he overtock so quick.

And you two thinkers instead of having a little fun playn around with air filters, you insult me for giving a honest correct comment? Cant belive it.

 

One thing to remember is when you get headers with an open element, WRAP THE HEADERS! It will definitely help with the whole hot air problem. I actually noticed my hood not being as warm when I had manifolds.

 

Hey now. Lol I was never insulting anyone. Sorry if it seemed that way. Hey we all know what we know, that's it. I have no idea that you know what the real deal is seeing is that you stated numbers that where not even close to what I would have thought. If you know better then me then great. Help me then. What type of set up is the best? Honest this is why I am here. I try to help, & be helped.

I have a slow as s 89 Lo3 TBI. I was thinking about getting a open K&N filter, & open filter lid. Then adding a fiberglass 4" cowl hood. Also I think it would help to keep the stock headlight tube in order to bring in more cold air. May be a good idea to Add the second tube. What do you think? I posted my best idea of a total home made air intake set up, but no one said anything good about it. I will add the link in a few.

 

K so here was my idea. All in all it seemed like a good one. Just an overview in case I loose ya. The system would have more filter area, since the K&N will have to be taller, & the filter lid will also be put on. The air coming in will be from 3 places, with only one of three getting air (MIXED) via the cowl, & under hood. Let me know what you guys think. Tweak my idea or give me a way better one.

Have the 89 rs-lo3 (tbi 305). Been thinking about cold air. Here is what i have come up with. Tell me if you think this could work.

Camaro / firebird dual snorkel air cleaner. Cut it all the way around about one inch lower then the lid. Weld in more metal in the center of the cut to make it taller. Add the second duck work by the right headlight. Add a k&n with the k&n filter/lid. Then put a lid from a 82-84 firebird with the hole in the top. Add a 3" cowl hood. Take the weather striping out from the rear hood seal to help the underhood heat leave.

Just wanted to put this idea out their, and see what you all think? Would the hole on top of the second lid work to pull in cold air with no ducting, doing away with the firebird design, and not just pull in hot air ,even with the weather striping gone? Would the motor some how take in water from rain, or the carwash? Should i keep the idea, and use just a solid outer lid doing away with the one that has a hole on the top? I know now that the screen is a must also with the cowl hood. Thanks for any thoughts. Any other good ideas might help. Maybe my idea is a dumb one? Been reading too much on this to find little info that helps.

 

You won't get a dual snorkel air cleaner to work on an 89 LO3, the heater and AC stuff are in the way of the second snorkel.

You'll gain nothing/very little as far as power goes when putting on an open element on a stock LO3. The engine is still limited by the heads and ECU as to how much power you can generate. If you want to improve the power of the engine without a head change, just upgrade the TBI (injectors, AFPR, ect.), air cleaner, exhaust, and get an EBL and tune your ECU you can add about 35rwhp. Thats according to Fast355.

 

This would explain why despite allowing more air the open element under certain circumstances isent effective.

Ecm adjust/optimizes the air/fuel mixture also taking air themperature in to account, the egr kind of keeps combustion themperature more stable by normal driving.

Knock does increase in hot weater, I endet up doing two different tunes one for cooler weather and one for warm, that has less SA. I have never actually compared the VE tables, will dafenately do it.

 

Wen I bought the headers I chosed ceramic coated ones, after installing them I did notice the hood was on the cooler side vs stock.


https://www.thirdgen.org/forums/tbi/...ir-intake.html

 

Heres my ...

Based on my experience and a lot of testing, with TBI, theres a lot more to the open element/CAI than just air temperature. TBI is a wetflow system. This means that there is live fuel in the intake charge. The gas can influence the temperature of the incoming air a lot. When gas evaporates, it absorbes a lot of heat, which can actually drop the intake charge down to below freezing when its cool/cold out. This is especially true at part throttle when the engien is pulling some vacuum. When the fuel enters into the manifold when its under vacuum, it can actually flash over to a vapor almost instantly like refrigerant in your A/C system.

What does this mean for a stock LO3? Well, the stock system is speed density. That means that the computer uses the manifold kPa, air density, and VE to estimate the mass of air coming into the motor for fueling. But, the stock computer does not have any way of knowing what the actual air desity is. Its assumed to be constant, and rolled into the base BPW calcs. The reason that there is no way implemented to compensate for changes in air temp is that the true air temperature is depenant on the outside air temp as well as how much the air is cooled by the evaporating gasoline. This is very hard to estimate and requires imperical models that take the vacuum, air temperature, and surrounding manfiold temperature into account.

This is the reason that GM gave the LO3 a low rise, fully heated intake manifold and air cleaner equipped with the thermac vavle. The whole goal is to maintain a STEADY intake temperature so the computer can properly fuel the engine.

When you add an open element, ram air, or a CAI, you can throw the fueling way off if you live somewhere where it gets cold. This can have a dramatic effect on how the engine runs. For this reason, its preferable to run a dual snorkel with functioning thermac valves. This keeps the air temps coming into the motor more constant. Warm in the winter, but not too hot in the summer. The downside is that the dual snorkel is $$$, and hard to come by. As far as the open element vs. stock intake, its almost impossible to do back to back comparisons on how one will perform overall compared to the other. If you live somewhere nice like san francisco where its cool year around, than the open element may offer some gains if the stock air cleaner is restricting the motor. If you live somewhere like colorado where its HOT in the summer and COLD in the winter, the open element may hurt a lot due to the fueling going all over the place.

I have done actual testing of an open K&N vs. a TPI box that takes in cool air on my TBI system. But, this was my custom system that used an LS1 mass airflow sensor as well as an unheated intake manifold with dedicated temperature sensors for the manifold temperature and incoming air temperature. This system could fully compensate for all the changes in air temp from the gas evaporating in the manifold, so it gave consistent results. IIRC, with a k&n cone element taking in hot air off the radiator, my 0-60 time in the winter was about 5.7 seconds. With a stock unmodded TPI airbox, which was more restrictive but took in cold air, that time came down to around 5.1 seconds. One drawback to the cold air, though, is that when its real cold, the manifold would ice up on occasion. Also, on start-up with a completly cold motor and air temps well below freezing, if I revved the engine or floored it, it would actually shoot jet black smoke and raw fuel out the exhaust. This was because the fuel and air where so cold that it simply wouldnt evaporate and mix in with the air. This resulted in a heterogenious mixture in the cylinder. Not good for drivability.

The cold air definitely can make the engine faster, but only if it can compensate for the change in air temperature, which the stock speed density system can't. Cold air may actually SLOW the engine down with a stock TBI system. If you tune for the cold air temps, then the opposite can happen in the summer when it gets hot, the engine will go way rich and run even slower than it would have originally. Its not a clear cut answer to whether one is better than the other. But, on modded motors, you almost always have to use something other than the stock single snorkel since its so restrictive.

If you do use an open element, its best to steer clear of the cowl induction if it gets cold out. In cold temps, it helps to have the air pass through the radiator to pre-warm it first before entering the engine. This means running the stock hood, or blocking off the cowl.

 

Well regardless if you think about it the open element is better than the stock air induction system. I'd rather have alot of hot air than insignificant amounts of cooler air.

 

I put the stock filter housing and snorkel back on my car about a month ago when I took it to get it inspected. The inspection place is about 10 miles from my house. I noticed a HUGE loss of acceleration with the stock setup compared to my open element. After I got my new inspection sticker I couldn't get the car home quick enough to get that garbage off and put the open element back on.

I run an open element in central Texas where it's HOT pretty much all year (hell, it was 85+ today). I pulled the rubber seal on the rear of the hood over 2 years ago and trashed it. My little bone stock LO3 has 210K miles on it. It leaks a little oil, but with the open element, 3.27 gears, and the T-5 swap it still gets 25-26 MPG regularly.

How much HP do you get swapping the stock setup for the open element? Nobody has a factual answer....and to be honest, who cares? If you cared about HP you wouldn't still be running the LO3. But, in my experience the open element puts up big numbers on the butt dyno.

 

EXACTLY!!! WHO CARES!!! If someone said the open element would give you 100hp would that make your car any faster, NO! Just do it because it is a great starting point. 8 years ago when I first got my 90 RS (replaced with an 02 Z28) I knew absolutely nothing about cars, I started with changing the oil and said, that wasn't too bad. After doing a **** load of research on this very board during my first year of college I said, hmmmm, maybe i'll install an open element, did it and said, that wasn't too bad either, maybe I should install some headers, and so on. By the time I was done I had install a bunch of bolts on, full suspension, a new transmission and torque converter and had new gears installed in the rear end. I got the car running 14.7s without the torque converter and new transmission and that was with stock heads, tbi, and intake manifold. Have fun with the car, use it to learn how to work on cars, don't get too caught up in the HP numbers. The funnest thing to do is get a quarter mile baseline, add new mods, go to the track and really see what kind of gains you made. No one can argue with track times.
Another thing to try to keep from doing is horsepower stacking or assuming you are going to get a certain amount of HP without any real knowledge, that just leads to arguments on here and gets everyone off topic.

 

i have open element on my car as well, not sure if i am gaining alot of hp even with the ra II hood, but it looks way better than stock thats one thing for sure.

 

what exactly are you referring to when you say "open element?" it may be i just know it by a different term, or maybe i just dont know it at all, which is just as possible.

so anyone got a pic?

 

http://store.summitracing.com/partde...5&autoview=sku

People call it an open element because the air filter is open to air all the way around.

 

check my signature link at the bottom here, there is a pic of it in the car.