Bovs

[Jimlad]

MTTE has this listed, as suitable for all MR2 Turbos..

I want one....

do they do anything apart from make a nice noise ?

[Bibbs]

nope ..

and they causse fueling problems .. Mine doesn't run smooth after gear change ..

Look for my (very) old posts .. this I explained it before the TOC data crash ..

[Jimlad]

I want nice BOV noise....

[Bibbs]

I'll sell you my non SQV BOV (HKS) .. but I'll want your re-circ too.

[Jimlad]

I'll sell you my non SQV BOV (HKS) .. but I'll want your re-circ too.

non sqv ??

whatsa that then ?

Also... y you want my recirc ?? Will I need it ?

[DeusMR2]

rev 1 and rev 2 (i think) had AFMs which didnt compensate for the loss of air into the cylinders when the aftermarket BOV vents the high pressure air to the atmosphere. So the ecu sends extra fuel into the cylinders thinking theres enough air for complete combustion..of course, there isnt and this causes stumbling after the BOV activates. It also causes protective oil to be stripped of the cylinder walls (Called bore wash i think) because of the extra fuel. rev 3 and higher have a MAP sensor instead of an afm and they can properly compensate for air loss, so fitting an aftermarket vent to stmosphere type bov isnt a prob with these revisions and higher.

its all cos the stock bov is a recirculating type and doesnt vent any air to the atmosphere,ive heard that there is a bov by HKS called the HKS SSQV or summin which is a recirculating type but also makes a nice whoosh sound when coming off boost. probably expensive tho cos of the brand name (sicne whens that been a prob for jimlad tho ;) )but i think itd be alright for rev 1 n 2!

[DeusMR2]

doh! jsut checked your pic n obviously you already have the SSQV in which case i dont think you have a prob cos it is recirculating, which is important for rev 1 n 2

[Bibbs]

rev 1 and rev 2 (i think) had AFMs which didnt compensate for the loss of air into the cylinders when the aftermarket BOV vents the high pressure air to the atmosphere. So the ecu sends extra fuel into the cylinders thinking theres enough air for complete combustion..of course, there isnt and this causes stumbling after the BOV activates. It also causes protective oil to be stripped of the cylinder walls (Called bore wash i think) because of the extra fuel. rev 3 and higher have a MAP sensor instead of an afm and they can properly compensate for air loss, so fitting an aftermarket vent to stmosphere type bov isnt a prob with these revisions and higher.

Yup - exactly .. the SQV can be made re-circulating .. but this makes it quiet.

non sqv ??

whatsa that then ?

Also... y you want my recirc ?? Will I need it ?

I've got 2 HKS BOV's and one is an "SQV" the other is a "Super Blow Off Valve" .. I wanna keep the SQV.

I need the re-circ to plug the hole that the SBOV will make when removed ..

[Bibbs]

and HERE is the techie detail as to why not ..

[Jimlad]

so the super sqv is fine for a rev1 ?

[Bibbs]

nope ..

Only a re-circulating BOV is good .. and a re-circ one makes NO NOISE !!

[Jimlad]

so does your one make a noise ?

[Bibbs]

Both do ..

The SBOV makes a "whooommmphsss"

and the SQV makes a "WEEEe, ptisch pistch"

[Jimlad]

I meant If I put the one from yours on mine would it make a noise ??

How would you describe the stock noise ?... lol

[Bibbs]

Yeah .. it would make a "whooommmphsss"

Stock noise .. there isn't one .. " "

[Jimlad]

I want I want I want !!

Got any pics ? In good nick ??

stock makes a funny "Phmpf" noise

[Bibbs]

Looks like this .. Ebay ..

[Bibbs]

[Jimlad]

... so when does it make the noise ??

When you let off the boost ?

Is this the only BOV you can get that's suitable for the rev1 ?

[Bibbs]

NO BOV's ARE SUITABLE FOR A REV1/2.

and it goes off when you lift off the throttle .. changing gears etc ..

[tony4]

will apexi safc cure this problem? they have quote:

"the Deceleration Air Flow Correction function is capable of curing the erratic idle and stall problems associated with open-atmosphere blow-off valves on hot-wire air-flow meter systems"

orelse, how about getting an ECU from rev3??

[Bibbs]

ECU for a rev3 will not work .. you'll need all the other bits (map sensor, injectors, turbo etc).

the safc sound like it does cure the problem .. but I also know that it's a nightmare on MR2's, causes all sorts of other problems ..

[tony4]

is it true that safc causes problem?? I'm planing to get a safc and savc.

what sort of potential problem we are looking at?

[Funkadelic]

You have to watch out for sticky nylon pistons on some BOVs.

Heard a story of a guy who had a few problems with an aftermarket dump valve on an Audi S4 which buggered up one of the turbos. Audi refused to replace the turbo under warantee for obvious reasons (the aftermarket dump valve)... This suited him fine because he just upgraded to larger turbos (although you can bet that wasn't as simple as a straight swap).

Turbos are almost enough trouble in terms of keeping them well oiled and working properly without BOVs too, in my opinion.

But the sound is sexual ;)

[Bibbs]

is it true that safc causes problem?? I'm planing to get a safc and savc.

what sort of potential problem we are looking at?

I think it's due to the learning ecu .. you adjust all the settings, then the ecu changes and the setting are now buggering up the fueling ..

drop a post to IMOC and you'll get more techie details ..