Balzdpr

Why does my stock 2002 Civic EX accelerate faster and with noticablely more HP than my slightly modified 2005 Civic EX?

BlueEM2

iTrader: (1)

It shouldn't.. What have you do to the slightly modified one?

gearbox

iTrader: (95)

depends on the condition of the motor, etc. im sure there are many civics newer than mine that would feel slower due to lack of maint. also the stock setup was designed more for lower rpm driving in the city, so the intake/header/exhaust is smaller and keeps the air moving faster than aftermarket parts.

maxtierney

iTrader: (5)

That's because a select few 02 Civics came from the factory secretly modified by Mugen with 230bhp. I happen to have one of those cars. Just kidding.

I am assuming both are the same transmissions. 02s came with steelies vs alloys (not sure of the weight difference). As Gearbox mentioned, what mods do you have on the 05? Bigger wheel/tires? ICE - stereo, subs, etc.? IHE?, these will typically affect low end and free up high end.

05s also have center bigger center consoles and rear headrests. Also, if you have side airbags, rear spoiler,aero kit, all weather mats, OEM MP3 player, etc. You can nickel and dime yourself to 50 lbs+. May not sound like a lot, but it makes a difference.

Kennykid2002

iTrader: (1)

^
The above mentioned

And I'll throw this out there:
Your 05 could have a sticky throttle plate

Balzdpr

The 2002 has roughly 160,000 miles on it and a maintance record that couldn't be gotten by a nascar. The 2005 has roughly 93,000 and has been treated the same. On the 2005 I have an AEM V2 intake with K&N filter and a cat back exhaust, also im running the 2005 with a racing Mishimoto thermostate and universal oil cooler. Both cars are running on thier specific years stock wheels. Both cars are being ran in the DEEP south and in conditions which by rites should never be seen by a car. High humidity and scorching 100 degree or more heat. Im curious about the mention of the throttle plate and all but I am no where inclined to mess with it. Im sure I could have some one check on that. When I make a comment about this issue boggling my mind I mean seriously it crazy. As far as im concerned its like night and day between these two cars. Oh yeah, both are automatics. Any suggestions?

Balzdpr

also I have railed the **** out of both of them on the same streatch of road and for sure no joke that '05 is getting killed by that '02. I can feel a longer boost of horse power when it gets ready to shift gears. and the throttle does appear to be more responsive.

Balzdpr

I have no extra weight in the '05 in fact I have less weight in the '05 than the '02.

maxtierney

iTrader: (5)

Heat soak with your AEM is not helping. I notice it in mild San Diego. 100+ degree temps, for sure. Your computer is leaning out your AF ratio due to high ambient air temp. Performance will drop off noticeably. Low end loss with your exhaust if its a cannister type. Wrap your intake and/or throw on a Injen Heat Shield. Or make your own.

Balzdpr

what can I do to remedy this issue? Should I wrap the intake in thermo wrap? Should I reinvest in a cold air system? Or could I place a aftermarket fan system that runs off of electricity from the battery near the intake filter? Any suggestions?

maxtierney

iTrader: (5)

Wrap will help some. A CAI will get heat soaked, as well. I've seen guys make heatshields, run cool air hoses and keep that tube that comes from the stock intake attached to fender for cooler airflow. Don't waste your time with the fans. Just need to wait for the heat to subside. K&N and Iceman make a plastic SRI.

MindBomber

My understanding is a CAI actually results in warmer air entering the tb, due to the length of the tube increasing heat soak. Wrap will help, as will a few coats of header paint, I'm skeptical of the effectiveness of heat shields because your engine bay is essentially an oven and they don't fully encompass the intake tube. The best performing intakes are definitely the plastic ones and that's been proven with on dynos, the abs plastic diy intakes even work well.

gearbox

iTrader: (95)

i feel a huge difference in the summer when its super hot out and my intake is too hot to touch, let alone the rest of the engine bay and the filter sitting in the middle. hotter air = worse performance. i bet its the mods making the 05 slower.

Balzdpr

I think you are correct but how can I get around this? I thought I might cut a whole in my hood and replace it with a scoop.

lowlife9

i would get hood spacers before i cut into my hood. these http://www.corsportusa.com/store/cat...oducts_id=1986 or take a trip to home depot and get plastic washers and extended bolts for a fraction of that price.

MindBomber

Just get this.

http://cgi.ebay.com/ebaymotors/K-N-F...-/200464469449

Balzdpr

Mindbomber, I want to keep my cuurent intake configuration if I can. With that said, Lolife9, what kind of issues can I expect if I install these? This is a cool idea and i just might use it- inexpensive- looks pretty cool- allows me to keep my current configuration.

lowlife9

maybe a little water splash mite get through in a torrential downpour but nothing to worry about. i drive around in the rain with a VIS evo style hood and barely any water get through.

Balzdpr

Great I love the way that it looks pretty sick. So ill add them to my list of next pick ups. Is there a DIY here about doing that to your hood or can you talk it out in here?

lowlife9

ehh its pretty self explanatory but ok take out hood bolts ad spacers with new bolts.

iSharix

Soo let me guess, in other words.. a hood tilt ?
My ex got this done on his '95 **** box hatch, I mean Civic , and he said there's not much difference besides making the car look broken ..

lowlife9

beauty is in the eye of the beholder.

Balzdpr

Hmmmm. I wonder how it would look if I doubled the spacers? Hell I took one look at the oicture on the web sale site and was hooked.

pjb3

It would think a CAI would always have cooler air than a short ram intake. Just to use some easy numbers, if the outside air is 100 degrees and the under hood temperature behind the engine is 150 degrees, a SRI will be pulling air that is 150 degrees. A CAI may start with air at 100 degrees and it may warm up as it passes through the area behind the engine but it will never reach the 150 degrees, more like 110 degrees.
I agree that materials such as plastic would minimize heat transfer. My guess is the hard part with a CAI is to actually pull the 100 degree outside air and not pull heated air from a different part of the engine compartment

maxtierney

iTrader: (5)

Air in CAIs have twice the metal tube to flow through with more bends. Temp readings for both have been made at the throttle body, with nearly equal temp readings once heat soak has set in.

gearbox

iTrader: (95)

the laws of thermodynamics apply here, and usually air moving that fast thru a small section of pipe will not heat up much. you have to account for the air speed. if you are pulling 100F air from outside the car and the engine bay and intake pipe is 150F, that air will still be close to 100F by the time it reaches the engine. maybe 10F hotter if that. the air is moving so quickly that there is hardly any time for it to heat up passing thru the pipe. many people over at ecomodder have shown this by measuring intake air temp near the TB with the factory "semi cold air system" and then again with their warm air intakes drawing air near the engine. every time the warm air intake would draw in vastly hotter air, which is what they are going for to get better mpg at the expense of power. usually good mod for 5-10% fuel savings. in the winter, the engine bay is much cooler so you dont see as much of a difference.

Balzdpr

Ok I have read some interesting things in here. So bare with me when I bring this concept to your attention and if you have already heard of this or understand that it may not work let me know and then I can move on to something differant. We could move on to something differant.
When running your air conditioner you have to utilize the belt system of your engine. This robs power.
What if there were a way to run that system for short periods of time via electricity? Not for long periods of time, but in short controled periods where the cold air from the ac unit was compressed into the intake at very precise rates of control. So you would get the normal air and then the cold air in controlled burst.
Now the unit would have to be engaged at specific points in the power band simular to a turbo but with colder more dence air. When I think of it it sounds awsome but it cant be that awsome or someone would have thought of it.

maxtierney

iTrader: (5)

There's a simpler method called *Nitrous Oxide.

Balzdpr

AHH **** just foolin' I didnt think it were to serios anyhow.

maxtierney

iTrader: (5)

I agree with you to a point. At idle (and heatsoak), temperatures are going to be similar at the throttle body, because most of the airspeed generated through the tubing is based on throttle position and to a lesser degree, outside airspeed. Factor in the conduction of heat transferred from the engine to the TB, as well.

At speed, the temps in the engine bay will decrease with movement of the car, and the the amount of the drop being proportional to the ambient temperature outside. However, it is very unlikely that there will be a temperature difference of 50 degrees between the CAI and SRI, unless there is a direct feed of cool air to the filter. In order for this to happen, the filter would have to be placed lower than the front bumper and undercarriage or have a tube feeding the filter from the outside. Most CAIs I've seen are still tucked in the engine bay. We'll call the difference 25 degrees vs 50. Factor in another 10 degrees for heat transfer to the pipe. And were talking a difference of 15 degrees - maybe.

Ahh, I found found one of AEMs intake illustrations. I knew it was somewhere in between.



Some strategies used in designing cold-air intakes are:

- Increasing the diameter of the air intake, allowing increased airflow.

- Smoothing the interior of the intake to reduce air resistance.

- Poviding a more direct route to the air intake.

- Tuning the length of the intake to provide the most airflow at certain RPMs.

- Using a more efficient air filter