blow off valve

[GTOjoe]

I heard that on new turbo cars, if you put a custom blow off valve on your car it voids the warranty of the car or the engine. I heard that b/c you may need to cut into things to put it on and if you dont cycle the air back into the engine that is another reason it would void the warranty... Is this true... and is there anyway around this if it is true???

Thanks

[Igovert500]

Well some dealerships will bitch that any aftermarket parts void a warranty. But I would definantly argue it if they tried, becuase the ONLY way a BOV could do any damage at all is if it was overtightened and didn't vent, and caused compressor surge. Other than that, they would be hardpressed to prove a BOV caused any other issues or was related to any damage. I remember a guy on 3si, going through this with a dealership. They were saying something stupid, like a BOV was the reason he spun a bearing or something. Anyway, I think he fought it and won....I know I would. You just have to keep going higher and higher.

Anyway,
1) I don't see how this would be limited to only 'new turbo cars'
2) Not all aftermarket blowoff valves vent to the atmosphere, many do vent back into the engine just like the stock one.
3) I don't know of any where cutting is required. I had to relocate mine, but that was only a matter of adding a 6 inch piece of tubing...didn't cut anything.

[Igovert500]

Well some dealerships will bitch that any aftermarket parts void a warranty. But I would definantly argue it if they tried, becuase the ONLY way a BOV could do any damage at all is if it was overtightened and didn't vent, and caused compressor surge. Other than that, they would be hardpressed to prove a BOV caused any other issues or was related to any damage. I remember a guy on 3si, going through this with a dealership. They were saying something stupid, like a BOV was the reason he spun a bearing or something. Anyway, I think he fought it and won....I know I would. You just have to keep going higher and higher.

Anyway,
1) I don't see how this would be limited to only 'new turbo cars'
2) Not all aftermarket blowoff valves vent to the atmosphere, many do vent back into the engine just like the stock one.
3) I don't know of any where cutting is required. I had to relocate mine, but that was only a matter of adding a 6 inch piece of tubing...didn't cut anything.

[Linebckr49]

Igovert is right.

all turbo cars have a blow-off valve. there are 2 forms, open-atmosphere and closed-loop. the former type is the category into which most aftermarket BOVs fall in. people like the open-atmosphere BOVs because they make a sound when pressure is released into the air. the "whoosh" sound is "cool."

the closed-loop BOV circulates this released pressure back into the engine. i forget entirely why the recirculation is necessary, but it is beneficial to the engine. now some might argue that the lack of this benefit (open-atmosphere BOV vs. closed-loop BOV) might cause engine problems, but not likely.

google search BOVs, or hit up www.howstuffworks.com and find more about the closed-loop BOVs. i'm just too lazy to search right now. i'd be interested to hear what you find.

[Igovert500]

The only benefit is that our cars are MAS-metered. All incoming air is computed for through the MAS and ECU, so when the BOV opens to vent, a recirculating BOV vents the air back into the intake (behind the MAS) so that no previously-accounted-for air escapes.
An open-atmosphere BOV vents it out under hte hood, which makes that noise, but then metered air is lost, and hte car will run rich because the ECU has sent teh correct amount of fuel for the air it thought was going into the engine.
So basically you run rich right after letting off WOT and right after shifting. You can compensate for it with an air/fuel controller, although many run open BOVs without any A/F control and have no problems. So it is really a toss-up that comes down to preference. Again, either way, anybody would have a hard time arguing that a BOV could cause any problems to an engine that would warrant voiding a warranty.