New Vortech Maxflow Blow-Off Valve Upgrade for FT86 Supercharging Systems

[ft86me]

Originally Posted by F1point4

Fun times?

nice vid! for your info, i tightened it down A WHOLE LOT we are talking 6 or 7 full rotations and the discharge of constant air sounds like a little bit of a whistle the whole time and shifting and blowing off sounds like a loud whistle equiv to a hks ssqv. now when you are in the 4k range with barely on the throttle it's a screamer, the whistle is so damn loud it's unbearable. I slowly increased the level of it being tight and did literally about 20 different test drives and could NOT eliminate the whistle. It just progressively get's higher in the RPMS and much louder with it being tighter.

For example, if you are cruising in second around 4k (this is about 3 and a half turns) and try to cruise with some throttle you will hear and EXTREMELY loud whistle. if you give it more gas you will hear it even more and if you slight let off it's back. it sounds like someone is whistling at a cute girl or something. shifting is like a high pitched whistle at first followed by a little pshh. Higher rpms is a solid whistle. Mind you cruising was bearable and pretty quiet but when you apply some throttle that whistle is obnoxious.

Due to my trial and error with all those test drives and putting the car up and adjusting, I can fix the issue. I loosened it back up to where it was when it came out of the box and will be switching back to the old pipe when I have time. Unfortunately, this isn't working for me.

[F1point4]

Interesting. You make me not want to touch it at all.

[ft86me]

Originally Posted by F1point4

Interesting. You make me not want to touch it at all.

I honestly wouldn't. I would wait until vortech figures out a spring solution that'll keep quiet while cruising then open up nice while blowing off. They are working on it now so says rick just no final product yet. I'm sure we will know once it's out.

Tightening a lot = quieter driving conditions and lower rpm shifts like 2k is the louder whoosh like the stock bypass from vortech. The Whistle is not present cruising BUT give it slight gas and around 4k it'll make that super loud, I mean loud whistle like a dude whistling at a chick. Also , when you step on the gas it'll make a title whistle. You can tell when it's closing and opening. Blowing off is a whistle and high rpms is a straight whistle. Actually sounds bad ass. I just cant do this because I cruise on the freeway and giving it some gas initiates the whistle and honestly it's too loud and sounds like my car is broken. Slightly embarrassing.

Loose = well loud discharge and slight whistling with more pshh noise when blowing off. I opted for this solely because of the whistling issue. So it's back to what it was but maybe a little tighter and I don't hear a whistle so far. It's coming off though unless I hear from vortech before I take it off since I need to make time at my shop to do it or figure something out w dj carbine.

All in all I'd leave it alone. It sounds way better untouched to be honest and it's pretty bad ass but just not me.

I'm actually talking to dj carbine since he is interested in mine. I may pick up his setup since it's not loud enough for him.

[86design]

i want so bad.....

[F1point4]

Did some more homework...

Vacuum Studies

My AEM Failsafe gauge shows boost and AFR at the same time. It has two displays, an LED ring and an digital display. Before I had the ring set to show boost and the digital display to show AFR.

Today I reconfigured both to show boost so I can study what the car is doing at different levels of vacuum and what the Vortech Blow-Off Valve is doing.

I recorded a bunch of video using my GoPro but I think its better if I just write it out **This is for my style of driving and my gauge, a different driver/gauge may give different readings**

-20" Hg is full vacuum, you are coasting in gear
-19" Hg is vacuum at idle with no AC
-17"/-18" Hg is vacuum at idle with AC

-18" Hg vacuum is throttle used to maintain speed
>-18" Hg vacuum is acceleration. The greater this number the faster you accelerate

-12" to -15" Hg @Rick@Vortech tells me he thinks the valve is fully on
-10" Hg to me sounds like the Blow-off valve is fully on

-6" Hg the valve starts to open. I can hear air come out. Advertised starting point
-5" Hg the valve is definitely off

The loudness of the whooshing/whistling depends on how fast you are going and on what gear. Vacuum is vacuum and the BOV operates the way it does regardless of how fast the car is going.

If the valve is fully on at -10" Hg that doesn't leave us much room to play with the spring. Logically tightening the spring so it opens at higher levels of vacuum should increase the point where the valve is fully open. Regardless its not that much room.

Regardless of if the BOV is open at -10" or -12" Hg, cruising is -18" Hg so the BOV is fully open anyway. I think I agree with @ft86me that adjusting the valve to get rid of the whistle won't work. I think something in the BOV itself has to change if this is the goal. Many thanks to him for actually getting under the car and adjusting the valve.


I may sound like I'm ragging bad on this kit. I'm studying this because I want to understand what our cars are doing. Yea the BOV whistles loudly but everything else it does is pretty badass. I get lots of kudos on the road. @Brian@Vortech and @Rick@Vortech did a good job designing the thing.






Side note, some people think the Vortech kit makes boost all the time and ramps up boost when Engine RPM goes up. Not entirely true; centrifugal superchargers build boost like on an exponential scale. In low RPM the blower doesn't actually make boost. This is good because its easy to stay out of boost; I find myself never making >0 PSI boost in daily driving unless i'm womping on the car.

Here's fun video of me doing a 3rd gear pull with the gauge set to boost. Looks like I am making 7.6 PSI at 7400ish RPM

[ame="http://www.youtube.com/watch?v=lqSjK9gaAk8"]3rd Gear Pull with Digital Boost Gauge - YouTube[/ame]

[ft86me]

Originally Posted by F1point4

Did some more homework...

Thanks for the kudos in the post!

I would have to agree with you that the blow off valve need some sort of altercation in order for it to eliminate the whistle. As said before, I believe vortech is working on a spring solution.

Don't get me wrong, the idea was an awesome idea and is sounds freakin bad ass! The last three days I've had it were very very fun while taking it up and blowing off and doing massive amounts of adjusting. Trust me, I was breakin necks and getting thumbs up from some boosted heads with subies and evos. So major props to vortech and their engineering and brian and rick!!

Unfortunately, it's not for me. As bad ass as it sounds, my taste is not with this unit. So due to that, I sold my unit to someone here on the forum that wants the pipe and blow off and has traded me his current setup of another blow off/bypass. Win win situation for me and the other guy.

[DJCarbine]

Just installed.... Oh my.

[ft86me]

Originally Posted by DJCarbine

Just installed.... Oh my.

Thanks for helping me out dude !!

[DJCarbine]

2.5K rpm = Flo Rida would be proud

[DJCarbine]

Going to try to run the valve a little loose. Its all fun and games until you scare children on the sidewalk with your screaming bypass valve lol

[DJCarbine]

So loose is a no go, however I tightened it until only 7 threads were showing on top and the whistle is gone

No more whistle at 2.5k rpm, in fact I don't hear any whistle at all unless its a redline shift, and it only lasts for a second

[ft86me]

Hahaa scaring kids lolol. Glad it's working out for you. I'm lovin your old unit !!

[MATTrocity]

how do I order one? I PM'd Brian with no response

[ft86me]

Originally Posted by MATTrocity

how do I order one? I PM'd Brian with no response

They are probably w sema