yoshgixxer

i have a procharger p600B on my 87 notch,car also has been converted to carb. my stock diverter valve is going bad i assume becuase it makes a horrible shuttering sound on discharge if its not really spooled up..if i open the valve with my finger and pinch off the vacume line the vavle snaps shut and wont stay open like it wont hold vacume..checking on the price of new deverter valves i can get a nice bov for the same price or cheaper..but question is do they work the same? dosnt the diverter valve need to be open when the car is idleing? will a bov do the same thing or not? only reason i want to run a bov is for the cool *** sound! haha

luckythirteen13

since your carb, it wont make any difference if you run a bov or a bypass valve

yoshgixxer

Awesome cuz I just snagged a turbo xs bov from a buddy!! Thanks !

yoshgixxer

Oh how much spring pressure should I run in the blow off valve..it's a turbo xs RFL valve... Do I measure vacume?

luckythirteen13

see thats the thing, i dont see why it matters because the vacuum line hooked to it is also a boost line. when the motor builds boost, it sends boost pressure into that line and into the top of the bov pushing it shut with equal pressure to the boost pushing it open. so all your really need is just a couple pounds of pressure, just enough to keep the bov shut till the line fills the top of the bov with boost pressure and from there it wont open till after you let off the gas. just be sure the line going to the bov is hooked to the motor in a place that sees vacuum i.e. AFTER the carb.

any pics of your setup? love to see it with the bov installed

yoshgixxer

Yea that's what I figured but was just checkin just incase.. I'll run the bov with no spring shims as a starting point..I want to weld the bung onto the intercooler pipe tommorow so it looks clean then I'll snap a few shots of the set up after it's done( if I can make it out of the house tommorow to get the stuff I need, we got over 18" of snow) I'm hoping the car will make more boost. The stock diverted valve was a horrible butterfly valve design and you could blow air through it with the valve closed.

yoshgixxer

ok got the BOV all installed today..im thinking i reduced the spring pressure to much..the bov dosnt close and shut its loud mouth till the vacume gets too about 9..so its open from 25 to 10 before it shuts,so from 10-0psi its quiet and closed..and jesus christ is it loud just driving around cuz its constantly dumping air till you step on it.. its freezing cold out here so i cant even tell if its making the same amount of boost..as soon as a smash it in 3rd it just blows the tires off and only spikes 5psi..but again its not hookin and im feathering the gas.. soooo..everything seems ok other wise..idle is a little surgey when you let off the gas but again this is probably cuz of the low spring pressure.What do you think?


oh ill get some pics tommorow and it makes the bad *** blow off sound now!

luckythirteen13

are you sure its blowing and not sucking while idling/crusing?

you could try adding a little more spring pressure but if you go too much, the valve wont open when you let off the gas. if its so snowy out you cant test, i would wait for a clear day. you wont get any decent info from it if your peddling the motor and spinning the tires

yoshgixxer

it feals like its blowing?? ill have to hold somthing in front of it to see if its blowing or sucking..which should it be? also whats the big deal if the valve is closed when its idling/crusing as long as it opens when i let off the gass after i run it up a little or at full boost?

only reason i wonder is the stock diverter valve was always open at a idle..

If its sucking at a idle that would suck..that would mean its drawing unfilterd nasty fender well air in my engine!!

yoshgixxer

It's deffinatly blowing air.. I tossed a pinch of snow infront if it when it was ideling and it blew it away! Haha.. By the way I got the bov closed at idle now in the drive way it still opens if you rev it.. Ill take it out and drive it later see if it's opening enough after full boost