Is replacing the factory airbox with an open style after market system. I bought my car back in February with a bunch of bolt ons like fabspeed headers, straight pipes, and intake. Since then I have excperienced a choppy throttle particularly on hot days, so I re installed the factory air intake and noticed a huge difference in throttle quality especially on a hot day like today. I personally do not recommend any after market open style intake system as it seems to just suck in all of the engines heat. Im so glad my Turbo as back to normal.

 

I think a lot of people forget that no matter how much extra air gets sucked in through the air filter, the DME controls what is actually usable.


The IPD plenums are good and so is a big 74mm throttle body. Invariably though, every time you change the A/F ratio, the DME needs to be programmed to make proper use of the additional air flow.


Bottom line is we can only go so far before the knock sensor kicks in and begins to retard timing. It takes a careful tune to understand just how much air/fuel/boost can be increased before the DME starts to retard timing due to knock.


When a tuner says their AF adds +25 RWHP, the AF mod on its own isn't enough to feel for most people. I personally think people feel throttle response and believe they are feeling HP when they are not, but that's just my opinion. Tuners also rarely tell you specifics about the test car, it's programming, test conditions, etc. The car will breathe better, you will see a marginal increase in gas mileage and better throttle response, but that's it.


There is zero wrong with the stock air-box other than it doesn't look 'sexy'.

 

I've just ordered the ipd in 68 ( stock mm ) rather than the bigger 74 mm as bigger isn't always better. I decided this after consultation that take into consideration the goals i have for the car as well as the Rev ranges I live in going up/down mtns all day. So im expecting some improved mid range oomph & throttle response in addition to the possibility of a bit more hp/tq. I'm keeping my modded dual cut lol airbox.

 

Well a bigger TB *IS* going to make more power by more air flow. With that said, bigger isn't always better as it definitely augments RESPONSE characteristics.


Just remember, if you're going to get an IPD plenum, it's a PITA to install. Should do it with the engine dropped.


I have an IPD plenum on my CTT, and IT DID make a noticeable difference in response and power.

 

thx for the advice. given this some thought, before deciding to opt for the smaller ( stock ) 68. i think i'll see gains, and the 74 isn't going to help me in the short up/downhill bursts the way the 68 will. at least, that's the thinking. we will see. if it helped your ctt? it'll help mine.

gonna do it in the driveway. piece of cake. but again.. thanks!

 

Was it easy to install the stock air box back in? I thought I read somewhere before that it was tough/near impossible to get the stock air box out?

 

Oh man, it took about 45 minutes of light cursing and head scratching before I got the factory air box back in. It has to go in vertically and then rotated clockwise once squeezed into the boot.

 

Worst mod is to lend your car in a daily swap for a 12C to a mate. He calls you to add fuel cause he has thrashed it for 100 miles. You tell him to put in 5 gallons 93 and 1 gallon E85 and he does reverse, bringing you back an ultra lean, backfiring, needing to be drained of fuel pain in the rump.

Worst mod = Turbo blankets, complete WOFTAM

 

About worst mods; EVOMS V-Flow.

Had so many blown MAFs with that, even with the new dry filter etc...

Back to original and no blown MAF since year 2010 or so.

Before that it was ordinary to go through at least 3 MAF's during every summer.

 

it has to come out to replace the element; a bunch of screws holding the sides together, but not a huge deal to r&r.

 

Thanks for sharing and interesting information about the V-box.

 

why do you feel this way? blankets keep the heat in allowing the turbos to spool faster and also keep the heat away from the coils, wires sensors and every other sensitive electrical part. may not bring out a bunch of hp but they have a place in the turbo world.

 

How does keeping the heat in a turbo help it spool faster? A heat shield would probably be a better way to protect surrounding components.

 

stock air box takes exactly 30 seconds to install once you've done it once. you need to put it in almost past vertical and rotate in to level as you slide it in. Super easy once you do it once.

 

Thanks, I will look for a used one. I haven't been able to find any on ebay or in the classifieds.