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BOV position

mattysaidso

By mattysaidso,
in Engines & Forced Induction

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R33vit Experienced

R33vit

Posted
Posted

Roy is correct.

A Pop off valve is fitted by the governing body in motor sports and is compulsory, where a BOV valve is not.

Two totally different operations.

POV's are to stop race teams running more than a pre-set amount of boost as defined by the governing body.

A BOV is fitted to help reduce turbo spool up time after a throttle close.

pnblight Mentor

pnblight

Posted
Posted

yes i know and they are all bov and proform the same task .whether a car use a vacuvm operated or spring set pressure unit. I personal know of no performance car that didnt run one or the other the WINFIELD GTR ran at 1.5bar bov and FORLUMA 1 IN 1988 were resisted to 2.3bar from memory they blow off valve service the same role as the vacuvm operate and you would gain no advanage to run both thats why you dont see this style on some race car but so say races dont use bov could be a bigger crock of shit

R33vit Experienced

R33vit

Posted
Posted

A POV will not vent on throttle liftoff. A BOV will.

They’re not the same thing.

As for racecars not using BOV may be correct. If you think about it, a champ car uses SWOL (Shift With Out Lift) so a BOV is not really needed here, but if the driver tries to turn up the boost to far in a race the POV will stop him exceeding the regulation limits.

As for a road car with the constant lifting of the throttle in everyday driving conditions a BOV will assist in a quicker spool up of the turbo.

doridori32 Rising Star

doridori32

Posted
Posted
A POV will not vent on throttle liftoff. A BOV will.  

They’re not the same thing.

As for racecars not using BOV may be correct. If you think about it, a champ car uses SWOL (Shift With Out Lift) so a BOV is not really needed here, but if the driver tries to turn up the boost to far in a race the POV will stop him exceeding the regulation limits.

As for a road car with the constant lifting of the throttle in everyday driving conditions a BOV will assist in a quicker spool up of the turbo.

It will not give you faster throttle response(boost response)in between gears... if it does on your car then your car is setup very shocking.

Doesnt help me spool up quicker in between shifts.. your wrong .. show me some proof it does.

pnblight Mentor

pnblight

Posted
Posted
A POV will not vent on throttle liftoff. A BOV will.  

They’re not the same thing.

As for racecars not using BOV may be correct. If you think about it, a champ car uses SWOL (Shift With Out Lift) so a BOV is not really needed here, but if the driver tries to turn up the boost to far in a race the POV will stop him exceeding the regulation limits.

As for a road car with the constant lifting of the throttle in everyday driving conditions a BOV will assist in a quicker spool up of the turbo.

i didnt say they were the same thing but they perform the same task and champ had blow off valve not pop off valve i can quote published documentation but for any interested parties have a read off FORCED INDUCTION PERFORMANCE TUNING by Graham Bell .This guy is a legend and has lived and breathed race all his life and it is well worth the read.

And someone tell me how a bov is for emissions is has no benefits for emission at all

R33vit Experienced

R33vit

Posted
Posted
i didnt say they were the same thing but they perform the same task and champ had blow off valve not pop off valve i can quote published documentation but for any interested parties have a read off FORCED INDUCTION PERFORMANCE TUNING by Graham Bell .This guy is a legend and has lived and breathed race all his life and it is well worth the read.

And someone tell me how a bov is for emissions is has no benefits for emission at all

I will give it a read, thanX for that.

As for now Im off to bed

Sydneykid Grand Master

Sydneykid

Posted
Posted
Sydneykid i would like to tell you your wrong.... very very wrong.

My Engineer told me to tell you that you don't know nothing and suck balls.

If you want his email let me know!

Im not being a smart ass but just giving you some real fact's. Stating BOV"s are useless pieces of shit.

HANG ON, have you got the posters wrong? All of my cars, race and road have BOV's?

Imagine your average joe driving this brand new series 6 RX-7 off the factory floor with the flutter noise every gear change. He would be straight back to the Mazda dealership asking if he has piston slip or has done a head gasket. Laughing

Just in case you are picking on the right poster, since when have rotary engines had pistons or heads? Headgasket? What's a "slip"?

:cheers:

Oosh Veteran

Oosh

Posted
Posted

I've read bits and pieces of Graham Bells FIPT, this isn't exactly on topic (and could start another sh!t fight), and i seem to remember it mentioning a race team who set their engines up to run no wastegates and instead use pop-off valves to regulate boost...

...i guess my point is (if i have one): just because race team X swears by method Y, it might'd be the greatest thing out there, and it sure as hell doesn't mean it translates well to the street.

Porsche make some awesome machines but you can't hold up what they do (or did years ago) and preach it to be gospel.

I think it's safe to say F1 is the pinnacle of N/A engine development and if only they'd bring back the turbos we could add those teams to the discussion. Which leaves WRC and Indy at the top of the current Turbo field (shame there's no more Pikes Peak or Group N) so i'd be interested to hear what those RACE teams run BOV-wise. Please, and i'm sure someone will, correct me if there are higher level race categories out there... we've already discussed LeMans 24Hr and to be fair that's a single race not a category IMHO.

Edit: Shows how much i follow Indy, looks like they run N/A V8's now, when did that happen?

doridori32 Rising Star

doridori32

Posted
Posted
I've read bits and pieces of Graham Bells FIPT, this isn't exactly on topic (and could start another sh!t fight), and i seem to remember it mentioning a race team who set their engines up to run no wastegates and instead use pop-off valves to regulate boost...

...i guess my point is (if i have one): just because race team X swears by method Y, it might'd be the greatest thing out there, and it sure as hell doesn't mean it translates well to the street.

Porsche make some awesome machines but you can't hold up what they do (or did years ago) and preach it to be gospel.  

I think it's safe to say F1 is the pinnacle of N/A engine development and if only they'd bring back the turbos we could add those teams to the discussion. Which  leaves WRC and Indy at the top of the current Turbo field (shame there's no more Pikes Peak or Group N) so i'd be interested to hear what those RACE teams run BOV-wise. Please, and i'm sure someone will, correct me if there are higher level race categories out there... we've already discussed LeMans 24Hr and to be fair that's a single race not a category IMHO.

Edit: Shows how much i follow Indy, looks like they run N/A V8's now, when did that happen?

F1 car's didnt have BOV's. Because they dont help your car in ANY WAY. Not even throttle off and on boost repsonse, and especially not turbo life.

WRC's car's dont run BOV's they run pop-off valves, just to regulate them in boost.. nothing else.

BOV"s are JIBBERISH!

doridori32 Rising Star

doridori32

Posted
Posted
point of thread: doridori32 doesnt like BOVs, so neither should you

Thread close

No, many people dont use BOV. Spend the money on something that is going to give you performance for your dollar.

with the 500$ or so you spend on a BOV you could buy yourself sticky tyre's or something else!!

Oosh Veteran

Oosh

Posted
Posted
F1 car's didnt have BOV's. Because they dont help your car in ANY WAY. Not even throttle off and on boost repsonse, and especially not turbo life.

WRC's car's dont run BOV's they run pop-off valves, just to regulate them in boost.. nothing else.

I've done a fair bit of searching on WRC cars and found very little info. on their engines, care to point me in the direction of some info. sources to back your claims?

Roy Grand Master

Roy

Posted
Posted

I have some articles on rally cars, they never mention specifics of ancillaries though...manily drivetrain and aero changes etc etc. Plenty of pics of engines though, and i have found it tough to find what may look lik e a BOV...i know the Grp N rally cars do.

LOL...someone will freak when i install a 2nd BOV on my car:)

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