Mazda Rotary Club

Cars by Model Type => 3rd generation RX-7's => Topic started by: jord13b on October 22, 2011, 06:50:39 PM

Title: GReddy Type S BOV - Question -You may think im stupid! :(
Post by: jord13b on October 22, 2011, 06:50:39 PM
Hey guys,

this has been bugging me for a while and need a straight answer...

Got my single turbo (greddy td06-25g) which has a screamer and external wastegate.... i dont like the screamer so wanting to plumb it back in, thus getting rid of external wastegate, right? or does it just plumb back into the exhaust with the screamer?? now, i want to use my greddy type s bov which is just sat on my shelf.... could i use it without having to have it remapped? cause i know itll make it run richer, but it runs rich anyway??

im sorry if this makes no sense... im crap with words and explaining stuff so can somebody kind of understand and help my wo\'s?? :(

just cant find anything on the web!

cheers,

Jordan
Title: GReddy Type S BOV - Question -You may think im stupid! :(
Post by: m1tch on October 22, 2011, 06:58:26 PM
The turbo will still need the external wastegate, plumbing it back in basically routes the pipe from atmosphere back into the exhaust further down, so it will be engine, manifold, then turbo/wastegate then wastegate to exhaust rather than wastegate to air.

You don\'t need the engine remapped for a BOV, the BOV will make the whole system momentarily rich when it opens (basically the air it lets out is already metered and so the engine has fueled for that air, but the BOV lets it out of the system) It won\'t run richer all the time, just momentarily when the BOV is opened when you let off the throttle. Which is why when you have it fitted it might pop and bang slightly when the BOV goes off.

Hope that helps
Title: GReddy Type S BOV - Question -You may think im stupid! :(
Post by: jord13b on October 22, 2011, 08:06:38 PM
so i wont hear the wastegate chatter no more as itll be going back into the pipe? also meaning itll be alot quieter coming on boost?

good to hear about the bov, hope it wont cause problems.... anybody know how to fit it?? which vacuum lines do i use??
Title: GReddy Type S BOV - Question -You may think im stupid! :(
Post by: m1tch on October 22, 2011, 09:02:43 PM
The wastegate will make the exhaust sound slightly different, but it won\'t be as deafening as it currently is.

Does anyone have a diagram to show their FD BOVs? I have an FC so its a bit simpler! My BOV is plumbed into one of the vac take offs on the intake manifold.
Title: GReddy Type S BOV - Question -You may think im stupid! :(
Post by: jord13b on October 23, 2011, 12:17:47 AM
yes pics or diagrams are needed!!!
Title: GReddy Type S BOV - Question -You may think im stupid! :(
Post by: philiwily on October 23, 2011, 03:44:03 AM
If its an FD a BOV won\'t make it run richer as it has a map sensor where an FC has an airflow meter.
Any vac line after the throttle body will do for a source.
Title: GReddy Type S BOV - Question -You may think im stupid! :(
Post by: jord13b on October 23, 2011, 10:27:34 AM
Quote from: philiwily;795770If its an FD a BOV won\'t make it run richer as it has a map sensor where an FC has an airflow meter.
Any vac line after the throttle body will do for a source.

well thats interesting to know, why is that? im not an electronic guru ya see! :(

so any vac line.... isnt there also a theory about positioning the dump valve properly to make it more effective? like closer to the turbo or something?
Title: GReddy Type S BOV - Question -You may think im stupid! :(
Post by: philiwily on October 23, 2011, 02:51:32 PM
A MAP sensor measures the pressure/ vacuum in the UIM, anything before the throttle body is irrelevant.
An Air flow meter is usually mounted before the turbo so any change in flow after the meter is relevant.
Any vac line after the throttle body for the vac nipple on top of the BOV, the most effective place to mount it is as close to the throttle body as possible.

Phil