cone filter vs. gutted airbox (track results)

[THe_DeTAiL3R]

Alright I went to the track last night, and although the track was SHIT (was cold, wasn't sprayed, and was dirty.. everyone was spinning their tires off the line) I have some results!

Stock airbox with new $10 filter (the snorkel part removed) VS. APC cone filter attached to stock airhose, and no IAT attached. 1988 Grand Prix, 2.8L V6 (with 1989 airbox conversion). No other mods.

 

Keep in mind that I was losing on average about 4 tens of a second due to poor traction.. I should be around 18 flat or lower now.

 

 

 

Stock airbox- with just me in the car, I was getting around 18.3. With my gf riding with me I was getting consistant times of 18.6

 

Cone filter attached to stock hose (IAT not attached.. shouldn't really matter though) - 18.6 was about the best I got, some were much higher.

With my gf riding with me I was getting POOR times, again a couple tenths of a second slower vs. stock airbox. At one time I even got 19 seconds with her in the car, a very poor time.

 

And NO my gf is not heavy, my car is slow.

[Brian P]

you should have tried the airbox with the snorkel on to shut up the people that drill a dozen holes in it

[Hippie]

Alright I went to the track last night, and although the track was SHIT (was cold, wasn't sprayed, and was dirty.. everyone was spinning their tires off the line) I have some results!

Stock airbox with new $10 filter (the snorkel part removed) VS. APC cone filter attached to stock airhose, and no IAT attached. 1988 Grand Prix, 2.8L V6 (with 1989 airbox conversion). No other mods.

 

Keep in mind that I was losing on average about 4 tens of a second due to poor traction.. I should be around 18 flat or lower now.

 

 

 

Stock airbox- with just me in the car, I was getting around 18.3. With my gf riding with me I was getting consistant times of 18.6

 

Cone filter attached to stock hose (IAT not attached.. shouldn't really matter though) - 18.6 was about the best I got, some were much higher.

With my gf riding with me I was getting POOR times, again a couple tenths of a second slower vs. stock airbox. At one time I even got 19 seconds with her in the car, a very poor time.

 

And NO my gf is not heavy, my car is slow.

 

What did you expect ? :? You are getting more air with the cone filter but not fuel to go with it. The air/fuel mixture leaned out so performance dropped off. The stock ECM can only compensate within a certain range of air flow and with the cone filter setup you exceeded the ECM's range. Computer management is a great thing but it doesn't alter the basics of the internal combustion engine, to make more power you need more air AND fuel.............. Likewise a major reduction in exhaust back pressure normally requires a recalibration of the fuel system. An internal combustion engine is a system and you can't just change one component and expect results.

 

And drilling a dozen holes in the air box does work IF you make the other mods to go with it. I prefer 15 holes personally. That's an old sleeper trick from WAY back ! We used to take the old single snorkel air cleaners and drill 1" holes around the base just outside the air filter. But you have to richen the air fuel mixture accordingly or it WILL slow you down. Automotive technology is light years ahead of what we were doing when I was your age and I don't profess to know much about the new stuff but the same basic rules still apply............

[Cornerdealy]

I just put in a gutted air box (drilled holes) and i definitely feel a loss of low end torque, but it sounds so cool.

[Brian P]

I had used a gutted airbox for a few months and I know for a fact that the car got slower and it was probably running 18's with a 3.1. The snorkel acts as a venturi and I'll leave it at that. Run down the track with it the next chance you get and you may be surprised

[TeeJay3800]

By norkel you mean the 5-6" long thing that is tapered at one end, and is at the entrance to the airbox, right? Removing that makes the car slower? I know that lack of restriction can cause a loss of low-end torque, but that snorkel seems like such an insignificant thing......

[Brian P]

it makes a stock engine slower....2 ways: by allowing too much air in (re: cone) and the air has less velocity without the snorkel

[TeeJay3800]

I understand that too much air and less velocity cause a loss of power on a stock engine, but does the stock airbox snorkel really make any difference?

[Brian P]

I'm saying from personal experience. The 3.1 was very doggy with the snorkel off. Loss of low end torque is very apparant, it was a chore to accelerate onto the freeway. All the engine would do is make noise and do shit

[TeeJay3800]

lol. I'm trying to decide if I should put it back on. Sounds like maybe I should. :?

[GutlessSupreme]

I'd have to find a new one. I didn't have a long enough socket extender to take the airbox out so I just drilled the shit out of the snorkel and ripped it out. I don't remember how it felt before I did it, but it feels like a fucking bloated whale whenever I drive it. It saddens me that I can only chirp tires while turning from a stop.

[Hippie]

I'm saying from personal experience. The 3.1 was very doggy with the snorkel off. Loss of low end torque is very apparant, it was a chore to accelerate onto the freeway. All the engine would do is make noise and do shit

 

Pulled the snorkel off my 3.8 and it didn't make one bit of difference except make it louder. :?

[Nick1234]

ok so i have my airbox cut in the front, and while i noticed a slight loss of low end torque, i think i got it back in the higher rpms. Throttle response is much better, and it doesn't gasp for air AS much as it used to prior to the romoval of the snorkle and the rest of the front of the box. I also am running a glasspack muffler, and i was wondering, is there anyway we can get more fuel without a different chip?

 

Nick

[Nick1234]

one more thing, doesn't the computer adjust to the differen't amounts of air and exhaust leaving the engine?!?!?!? With all the sensors, doesn't it tell the computer there is more air coming in, and add more fuel?

 

nick

[Cornerdealy]

I'm gonna test how my car feels tommorow, 1st with the swiss cheese gutted air box, 2nd with the regular airbox without the snorkle, and 3rd with the snorkle.

 

I'll post what I find.

[TeeJay3800]

I'm gonna test how my car feels tommorow, 1st with the swiss cheese gutted air box, 2nd with the regular airbox without the snorkle, and 3rd with the snorkle.

 

I'll post what I find.

Cool. Pay real close attention and be very observant please! I'm interested in knowing what you find.

[Baddflash]

I agree with Nick1234, After gutting out the side of airbox and adding k&n filter the engine definately breathes better in the top end, although I really didn't notice a torque loss. Add to that the excellent sound from under the hood and the price $0.00. If it wasn't an improvment I wouldn't have done it to my 2nd Lum as soon as I got it.

[THe_DeTAiL3R]

I didn't have the snorkle on because when I had it I couldn't get it to fit into the back of the lights properly. Keep in mind the '88s had the crappy ROUND airbox, so a box from a 1990 might not fit correctly. I just got the box with the IAT in it, no brackets or anything. The box is just kinda "sitting there".

Wish I had a 97+ ... the headlights can pop right out, so you can easily make a nice ram air setup with the stock box good for the track.

 

I only made this post to prove to those that didn't believe that cone filters (by themselves anyways) suck on these engines.

[Hippie]

one more thing, doesn't the computer adjust to the differen't amounts of air and exhaust leaving the engine?!?!?!? With all the sensors, doesn't it tell the computer there is more air coming in, and add more fuel?

 

nick

 

Only within a certain range, it's capabilities are not infinite, it is programmed for a compromise of emissions, mileage and performance. Once you have altered the operating parameters beyond it's range you need to reprogram. Some ECM's are apparently more flexible than others or in this case it may be that some airboxes are far more restrictive than others. An ECM that is calibrated for an air intake that isn't overly restrictive has a much better chance of compensating for a cone filter or altered air box than one calibrated for a restrictive system. "One size fits all" does not apply............

[Hippie]

Just for grins I went out at lunch time and popped my snorkle back on. We'll see if there's any difference on the way home.

[99RegalGS]

Wish I had a 97+ ... the headlights can pop right out, so you can easily make a nice ram air setup with the stock box good for the track.

Get a Regal. 2 bolts and they're out.

[THe_DeTAiL3R]

I'm wondering if the ECM/PCMs on the 3.4 DOHC cars can compensate good with a cone filter? I've heard of people with gutted airboxes getting good results.

[Hippie]

Just for grins I went out at lunch time and popped my snorkle back on. We'll see if there's any difference on the way home.

 

30 miles later city and highway and I can't tell any difference............ :| It's a little quieter and that's it.

 

I'm wondering if the ECM/PCMs on the 3.4 DOHC cars can compensate good with a cone filter? I've heard of people with gutted airboxes getting good results.

 

Since the 3.4 DOHCs were more performance oriented they may have wider parameters than other ECMs. :? ????

[jmacks92ste]

i have a 3.4 92 GP STE, and what I did was gut the airbox and modify the it to fit a 7' K&N cone filter directly into the box. This way the box works as a heatshield, instead of the typical warm air intake. In addition I have piping from underneath the car leading to the bottom of the gutted airbox, thus cooling the air into the cone filter even more than just the snorkel (which i also modded to be an even bigger snorkel). As for the ECM, I have the FFP chip. All in all, I noticed a very noticeable result with no torque loss.

[Nick1234]

pictures? sounds pretty nice