MazdaSpeed0020

I was reading about BOV and DV in a magazine and I found it interesting that if you have a MAF that it would be better to have a DV because it puts some of the air that would be blown to the sky back in the system. We had MAF in our Protege's dont we? I thought we did, I know I had one in the MX6 I had before, but I see people that are turboing their cars have BOV. And from what I have read, BOV are not the best for MAF. Thanks for any help.

Matt

atila

i have an bov on my gtx set-up and there's no real trouble except at first for the adjustement. The only time the bov open is when you let the gas off when the bov open who care if the mixture become to rich when you release the gas and it's to rich for 2 or 3 second the time you shift (if your really slow shifting) other then. You have to carefully set it to be shure it won't open when full boost come on then it would not be so good has the mixture would go rich and to a certain point to rich makes you loose hp.

P.S. the sound of a bov is so much better then the sound of a recirculation valve.

kagekun

half the fun of having a turbo is hearing that nice psssssssh. The civic board i goto, dont ask me why, they were talking about the same thing. Seems like its more of a do what you like kind of thing, couldnt find advantages or disadvantages

atila

It's not the same thing when you put a turbo on a honda they don't have a vane airflow at the start of the intake system they use a manifold air pressure sensor it calcul the quantity of air that goes in the engine by comparing the first data that the map send which normal atmospheric pressure has the engine is off and compare it with the pressure when the engine run so the air fuel ratio is calulated at the manifold not at the start of the intake so if there's leak in the intake they don't have any trouble try disconnecting the plastic intake on a protege and the motor die because the ecu doesn't know the quantity of air going in. The trouble with a bov is exactly that it's a leak in the intake system that the ecu doesn't know about so the fuel mixture is all wronght but the bov only open when you release the gas so it doesn't really mater except if the bov leaks under boost.

limpgtx

ive got a 1gen eclipse bov (by pass valve actually) and it does recirculate. can you really get away with having one blow in the atmoshpere?

atila

Yes like mine i have an apexi blow off valve the only trick is to adjust it so it doesn't leak on boost and at 0psi that the part i had the most trouble with it until i found the right adjustement

Farsyde

good lord atila throw some periods (.) and other punctuation in your posts. Just somethin to break it up. i have to read your posts like 3 times and fill in the blanks myself.

atila

Sorry, i'm for quebec so i'm not use writing in english, i don't have any trouble speaking it but i was always poor in the grammatical part in school even in french.

Farsyde

it's cool man i just haven't seen a single sentence that spanned 5 lines since i took spanish

MazdaSpeed0020

Thanks for all the help so far, I would like to get a BOV but I really dont know how I would adjust them because I dont know too much about them. How would I go about adjusting it so that it doesnt leak at 0 psi? What did you guys do to tune yours?

Thanks,
Matt

atila

On every after market bov there an adjutement screw to set the pressure at which the valve is going to open. You just release the lock nut and turn it to make it open under more boost or less when you release the gas. It's a trial and error methode, you have to road test the car each time as you adjust it, or go for a dyno run and adjust it when running. By the way if it's for a mazdaspeed be carefull, i think it will kill your warranty.

MazdaSpeed0020

Thanks Atila for the info, I want to do a few things to the car but it is under warranty and I dont want to void that, but who knows, I should figure out if I can do anything at all. Thanks again for everyones help.

Matt

Bruce95fmla

I would rather a blow off valve to ..
here is a photo of turbo1g's (Marcin) motor