EvolutionM - Mitsubishi Lancer and Lancer Evolution Community

EvolutionM - Mitsubishi Lancer and Lancer Evolution Community (https://www.evolutionm.net/forums/)
-   Evo X Engine / Turbo / Drivetrain (https://www.evolutionm.net/forums/evo-x-engine-turbo-drivetrain-258/)
-   -   acceleration jerking with bov (https://www.evolutionm.net/forums/evo-x-engine-turbo-drivetrain/541655-acceleration-jerking-bov.html)

reggiesd Feb 25, 2011 04:58 AM

acceleration jerking with bov
 
wanted to get some input on this, here's my current mods:

full tbe
nisei intake pipe/k&n filter
nisei 1 pc uicp
ams fmic
3 port bc
synapse bov (non-evo specific, the one with the side port)
custom tune

here's the thing, with the synapse side port hooked up to the 3port (T'd going to the intake), the car jerks on initial acceleration usually on 2nd & 3rd gear...kinda like the bov opens in the middle of acceleration, thus causing the car to jerk. so i decided to plug the side port on the synaypse bov, given my car has no down time since it's a daily driver & i don't have my stock bov anymore so i don't have the luxury of sending it back to synapse and having it retrofitted to be evo specific. after doing this, the car seem to accelerate A LOT smoother, although it seems i don't hit boost as high either. the car doesn't feel slower though...it just doesn't hit boost quicker and higher.

would a re-tune fix my boost issue? it doesn't look like i have any boost leaks...and what are the consequences of me plugging that side port on the synapse bov? any info would be greatly appreciated..thanks! {thumbup}

blk-majik Feb 25, 2011 05:33 AM

give it a couple weeks. sometimes the springs need to get broken in a little before they smooth out

reggiesd Feb 25, 2011 06:21 AM

I've had it for some time now though

KyLe EVOlved Feb 27, 2011 05:38 PM

I am kind of having this same problem, mine is happening when i go full throttle immediately, if you ease into your throttle does it have a nice gradual pull without the jerking?

TruSlide Feb 28, 2011 03:49 PM

i get this too. It ALWAYS happens in 5th gear at 60ish mph @ about 3k RPM coming off the throttle or holding steady at maybe 20%. Happens in other gears with similar ratios (mph/rpm/throttle). I just think it's because the turbo is trying to spool without enough air, right?

Jookies Feb 28, 2011 04:01 PM


Originally Posted by TruSlide (Post 9116141)
i get this too. It ALWAYS happens in 5th gear at 60ish mph @ about 3k RPM coming off the throttle or holding steady at maybe 20%. Happens in other gears with similar ratios (mph/rpm/throttle). I just think it's because the turbo is trying to spool without enough air, right?

I get this too, usually only in 5th, below 3k RPM. I always assumed it was because there isnt enough PSI to open the BOV firmly all the way, so it kinda just sputters a little. Jerks the car around too, kinda annoying lol. Was worried the first time it happened, but it seems lots of people have similar issues.

Edit: And i still have the stock valve, so I assume any aftermarket BOVs will have stiffer springs to handle higher boost, so the problem is probably worse with them...

TruSlide Feb 28, 2011 04:11 PM

Actually... with my BOV set all the way to stiff it seems to be alright. If I don't let off the throttle 100% instead of atmosphere release it just flutters and I get no sputter. But that acceleration jerking is annoying. I'm hoping once I get the parts to let it breath more it will go away or get better.

Jookies Feb 28, 2011 04:41 PM


Originally Posted by TruSlide (Post 9116197)
Actually... with my BOV set all the way to stiff it seems to be alright. If I don't let off the throttle 100% instead of atmosphere release it just flutters and I get no sputter. But that acceleration jerking is annoying. I'm hoping once I get the parts to let it breath more it will go away or get better.

Odd...with the stock BOV?

tephra Feb 28, 2011 08:03 PM

yeh you need to either set to full stiff or full soft...

Jookies Mar 1, 2011 05:29 AM

How does one do that?

nohlan_4 Mar 1, 2011 08:16 AM

My car also started doing this. When under full throttle acceleration it stutters until it's in the higher rpm. I have a crushed stock bov.

spdracerut Mar 1, 2011 08:24 AM


Originally Posted by nohlan_4 (Post 9117953)
My car also started doing this. When under full throttle acceleration it stutters until it's in the higher rpm. I have a crushed stock bov.

It shouldn't do it when you're WOT. It's typically an issue at part throttle where the pressure in the intake manifold is near 0psi boost.

In your case, I'd be more inclined to think it's a boost leak, or maybe worn out spark plugs.

nohlan_4 Mar 1, 2011 08:33 AM

Hmm...never thought of that before. I originally thought it was clutch slippage but they way it's surging it doesn't feel like it. It also doesn't do it if I ease into the throttle.

KyLe EVOlved Mar 1, 2011 03:34 PM

i deffinately think mine is cause of a leaking intercooler, wrecked the car and bent up the intercooler, im running a tial q, car ran perfect before the accident.

TruSlide Mar 3, 2011 06:18 PM

I have a turbosmart dual port BOV. It's not the stock so that's how I was able to set it to hard


All times are GMT -7. The time now is 12:27 PM.


© 2024 MH Sub I, LLC dba Internet Brands