The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Register Log in
Please Support ExtremePSI
Please Support ExtremePSI

bcs restrictor questions

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

dj99877

dj99877

15+ Year Contributor
87
1
Sep 24, 2007
LaCrescent, Minnesota
Ok, I have a completely stock 96 eagle talon tsi awd, I decided to do the bcs restrictor removal and everything came apart smoothly and went back together alright. Once i decided to take it for a spin at full throttle i noticed about a 1lb gain from my stock 14lbs to about 15, (not as much as I was hoping but hey, id take it) one thing i did noticed was that once i was going close to wide open there would be a slight hesitation and kind of like a very low popping noise, I was wondering if this was maybe like some weird early detonation or something i should be concerned with. If so I would put the bcs restrictrr back in. or my other question is I am currently looking into a 1g bov with a upic with the 1g flange to put on. would this help at all, and if so would that be just bolt on and go? thanks for all your comments. :)
 
Sort by date Sort by votes
You were making 14 psi with the BCS restrictor in? Seems high. Are you asking if an upper intercooler pipe and bov would help if in fact you are getting detonation at full boost? No, it wouldn't help that. The 1G bov would hold boost better and the upper pipe would allow a little bit better airflow. But the difference would be almost negligible from your stock upper pipe, especially with the rest of the pipes staying stock. But if you were to do that, yes, it would be a bolt on and go situation. As far as that hesitation goes, it's really hard to say, you're probably going to need some sort of engine management to pinpoint it. Have you checked for boost leaks at all? I doubt it was fuel cut at 15 psi. Do you have your car well maintained, good spark plugs with correct gap, etc?
 
Upvote0
It is pretty unlikely that you would be getting audible detonation from boost that low unless the engine/fuel system/air metering are very unhealthy.

You could be hearing the stock bov cracking open, or you could have something else entirely going on and you're only imagining the hesitation.

That said I wouldn't have bothered to try and raise the boost in any fashion without replacing the stock bov.
 
Upvote0
the_mork said:
It is pretty unlikely that you would be getting audible detonation from boost that low unless the engine/fuel system/air metering are very unhealthy.

You could be hearing the stock bov cracking open, or you could have something else entirely going on and you're only imagining the hesitation.

That said I wouldn't have bothered to try and raise the boost in any fashion without replacing the stock bov.
Click to expand...

I guess it isnt so much of a noise im hearing as much as a feeling a slight hesitation. I could be just imagining all of this i guess. I get parenoid about my car sometimes if something sounds or feels funny. and yes My car is well maintained, always check oil, Only have used mobile one. 90,000 miles on it. I am probably going to buy a 1g bov along with the IC pipe, considering I will probably be upgrading to a big evo III 16g once i have some more $$$ saved up.
 
Upvote0
TSiTuner23 recently swapped from the 2G factory BOV to a 1G valve on his '97 TSi FWD.....no other mods were done, and the car went from making no more than 14psi to making 21-22psi trailing off to around 16psi by redline on the factory T25.

Moral of this story....do what you want to the boost control system, the plastic 2G BOV becomes a wastegate at 14psi.
 
Upvote0
jusmx141 said:
TSiTuner23 recently swapped from the 2G factory BOV to a 1G valve on his '97 TSi FWD.....no other mods were done, and the car went from making no more than 14psi to making 21-22psi trailing off to around 16psi by redline on the factory T25.

Moral of this story....do what you want to the boost control system, the plastic 2G BOV becomes a wastegate at 14psi.
Click to expand...

Not only that but then it also hurts performance once you pass the point where the bov cracks open because you're basically never opening the actual wastegate causing the turbo to work harder than necessary increasing the heat of the outgoing air and reducing the outlet area of your exhaust. Simply put every 2g owner with a stock bov should perform a blt and then not increase boost past about 1-2psi below where the bov starts to leak.
 
Upvote0
Also I put the BCS restrictor back in but it still seems to sputter at full boost. Not quite sure why, im wondering if the BOV is wrecked now or something, does anyone have any ideas?
 
Upvote0
You must log in or register to reply here.

Similar threads

Ozone302
  • Question
BCS restrictor
Replies
9
Views
1K
Ozone302
Ozone302
Alex Bland
  • Question
BCS Restrictor 1991 talon
Replies
8
Views
568
Rob10_99
Rob10_99
coloradotuner
  • Question
why remove a bcs restrictor?
Replies
7
Views
4K
undefined0000
undefined0000
psychbiker1966
  • Question
BCS Restrictor Removal vs MBC
Replies
15
Views
7K
LiquidX
LiquidX
  • Question
BCS Mod / Restrictor removal [merged]
3 4 5 6 7
Replies
163
Views
35K
Rick_4g63
Rick_4g63
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top