Bypass Valve to Blowoff valve...

**PaLiAcH** · 05-03-2003, 02:51 AM

anyone done this??

pro's?

con's?

thanx!

i would like the blowoff valve kind of a sound, if its not too much of a hassle.... anyone know a part #? (i have a P1-SC upgraded to D1-SC)

**po-po 5.0** · 05-03-2003, 11:25 AM

A bypass valve, and a blowoff valve are the same thing. The only difference is that a blowoff vents to atmosphere as opposed to back into the system.

**PaLiAcH** · 05-03-2003, 04:44 PM

okay, so is there a better one to have or is it just personal preference??

**RI lx** · 05-03-2003, 06:53 PM

I have My ATI bypass venting to atmosphere, it doesn't make a turbo like phssssst, it sounds more like big rig air brakes or pulling the airhose on a shop compressor.

Its loud, and it can be heared even at idle or cruise when bypassing air cotinuously.

its probably just a matter of preference more than anything, the ATI valve moves a lot of air.

**Juiced46** · 05-04-2003, 10:44 AM

I ran a Greedy Type S blow off valve. I had a few drivability issues with mine. Bucking/hesitation. My car couldnt prduce enough vacuum to keep it open properly. it sounded just like a turbo car. it was pretty cool, aside from the driveability issues. I was venting to the air with that.

I just put a Vortech Race Bypass on my car a few days ago. Im venting this one to the air as well. it doesnt sound the same as the Greddy obviously. But all of my driveability problems went away :-)

**WA2FAST** · 05-04-2003, 11:22 AM

The only way you can blow air off to atmosphere is by running a blow through setup with the blow off valve before the meter. If you vent to atmostphere and have the meter before the blower, then your car will have major drivability issues. You can run it to vent to atmosphere without a problem if you are running a blow throug setup and have it before the MAF.

**po-po 5.0** · 05-05-2003, 12:16 AM

Originally posted by WA2FAST
The only way you can blow air off to atmosphere is by running a blow through setup with the blow off valve before the meter. If you vent to atmostphere and have the meter before the blower, then your car will have major drivability issues. You can run it to vent to atmosphere without a problem if you are running a blow throug setup and have it before the MAF.

Aren't all the ATI kits blowthru with the bypass before the MAF?

**Four eyed stang** · 05-05-2003, 01:59 AM

My kit came with the hardware to use it as blow or draw through.

So I guess, no, they aren't all blow through.

I know mine likes blow through far better though.

**WA2FAST** · 05-05-2003, 07:56 AM

They are not all blow through kits... a majority of them are, but not all of them.

**Juiced46** · 05-05-2003, 03:46 PM

I am running mine as a blow through with a Univer MAF. The blowoff is mounted right after the blower outlet before the IC

**WA2FAST** · 05-06-2003, 06:10 AM

Juiced46... I'm wondering now why you were having so many dirvability issues, becuase the BOV shouldn't effect your drivability. If you had the BOV anywhere after the meter weather it was a blow through or not, then I can understand, but before... that shouldn't effect it.

**Juiced46** · 05-06-2003, 01:11 PM

Well the only thing i can think of is due to my after market cams. I am only seeing like 9-10 inches of vacuum at idle. When you look at the valve at idle it is closed. So the car would idle funny. Under slight acceleration like 1/4-1/2 throttle the car would hesitate/buck badly. Also say in 1st or 2nd just rolling not on the throttle the car would do the same. I switched to the Vortech Bypass and did not change anyhting else. And it works perfect. The Greddy valve was to stiff for my application. I think it needed 12inches of vacuum to open. I think my driveability problems were due to the valve not opening/closing completely. Since i had it on the softest setting. When it did open it wasnt open all the way. I have heard of a few others that ran the Greddy valves have these same problems as well.

**WA2FAST** · 05-07-2003, 09:39 AM

That makes a lot of sense. Now I am wondering if I am going to have a problem or not. I am pulling 10-12 inches of vacume at idle, so hopefully the ATI BOV doesn't require a lot (the little metal tube with the butterfly plate). Do you think it will be a problem?

**Juiced46** · 05-07-2003, 02:26 PM

I am not sure. You will have to see what the specs are for the ATI valve to see what it needs for vacuum to open up. Is it the stock ATI bypass or the Race bypass? The reason why i went with the Vortech was that it only because you can adjust it to open anywhere between 3-16 inches of vacuum.

Dave