I installed the Apexi Power Intake (NO suction pipe) into my complete stock evo and found out the car run Lower Boost than before.....does anyone have the same problem?

>>>Before the Apexi intake, the boost pressure always spike up to 20psi for about 2 sec, then drop back down to 16.5 and holding though redline.

>>>After the Apexi intake installed, the boost pressure just spike up to 19 psi for 1 sec, then drop back down to 15 and holding

I did tight and check all the connection at the pipes include those at the By-pass-value, and already reset the ECU. I also test the car in the same outside temp.

I did a search and the only post I found was this one.....
https://www.evolutionm.net/forums/sh...t=apexi+intake

I will flash the ecu once I have all the parts but in the meantime, I try to see what cause the boost drop


TIA


btw....I love the intake, great fitment, car run smooth, and nice sound

 

where did you purchase and how much?? i must have one of these sometime soon, hope by this weekend.

 

I have the APEXi intake kit for the evo 8 it came with all the brackets and some install instructions mostly in Japanese. I have not had this problem to the best of my knowledge. Boost goes up to 19/20 and drops back to about 16/17 psi. However I do have the HKS suction pipe and use the safc2 settings that came with the APEXi filter kit.

 

my apexi intake kit is also designed for Evo 8. but I don't have suction pipe and safc.

 

What is the seat of the pants feel? is it slower?

 

Maybe try a mbc that should work. They go for 40-100+ bucks or you could go electronic. I just got a mbc, turbo smart the red anodize coating matches the valve cover. hope to have it in by tuesday. Any one else have better ideas or solutions?

 

i will buy the mbc when I ready to do the dyno flash.

I'm just so surprise to see lower boost when everyone say they gain xx power with intake!!

jemm.....my butt dyno and my boost needle say the car is slower as the car pull a bit weak than before

 

Try resetting your ECU by disconnecting the negative terminal for a few minutes.

 

As EvoJimbo said ... reset the ecu (pressing on the brake pedal to drain all the electricals is a nice tip) and if you don't have it on... put back the intake snorkel! (make sure the 2 black pins are secure).

 

The CT9A chassis cars really don't like when you remove the air snorkel CAI guide... thats why most of the jdm & rally guys either keep it or reuse the stock airbox.

 

did that already......when I did the install, the battery was disconnect for more than 20 minutes.

 

I just had mine install today, I'm 100% sure all the hose are tight, no leak, nothing. also installed hks induction pipe, Samco hoses etc... I took it out for a test drive tonite. Before the car spikes to 20 and tapper to 16 psi in 2nd and 3rd gear, after filter and induction pipe. Still spikes to 20 but tapper down to 15. 4th and 5th gear spikes to 20 and hold 16 to redline but was holding 17 to redline before. So Lose 1psi with the filter. Engine wise everything is stock. Will install my TB Tuesday and see if that will gain back that one PSI that I lost from the intake without the BC. Btw, ecu has been reset.

As for Performance I can't feel any power lose or gain with the filter alone. But sound wise, its loud as hell when the filter team up with the induction pipe. WHOOOSH WHOOOOSH every time you let off the gas, not sure if I like that in a long run or not....

Anyway here is a pic of the Apexi filter.

 

AFAIK lower resistance=higher flow=lower boost needed for same air flow. The less your turbo has to boost to reach the same CFM is good, it means you can push the boost higher if you feel like it

 

According to factory specs, the maximum boost is set at 19psi under full throttle, and decreases to 16.24psi. After installing my A'PEXi power intake, I don't notice any change in boost / vacuum pressure.

Because I already had a catback bolted on before the intake, I can't comment on the power gain with the intake alone. Still, judging by actual seat-of-the-pants feel, the turbo spools much faster, the engine runs smoother across the rev range, redline seems to arrive sooner than before, and the annoying power lose on the top end is gone.

It took at about 10 days for my ECU to adjust to the intake, so perhaps you can wait and see. The boost level shouldn't be affected unless you have a boost controller or other electronic modifications. You may want to check the accuracy of your guage. The stock setting shouldn't be at 20psi anyway...

 

no boost controller here, and my boost guage is new so I think it read the number right.

Anyway, my idle came back down 2 days after I installed the intake, it was idle at 1000rpm soon after I put in the apexi....now it came down to ~850rpm, close to normal at least.

I guess may be the ecu still haven't fully adjust to the new intake as you point out.