Synapse BOV surges when recirculated, ideas and advice please!

[teedoff00]

I installed a fitting on to my accordion hose last night and got everything all plumb, was looking forward to testing it out today. Then woke up to SNOW this morning! Well I guess I will have updates in a few days, hopefully. Anyway, pictures will follow, didn't turn out the exact way I had hoped because I got some hose kinking still, but we will see if eliminating the elbow and putting in a 1" fitting will help the problem.

Thanks for all the help guys!

 

[gottadiesel]

Hey man, seriously don't let my critical attitude towards them throw you off here. Seriously, as I said it may be a great product. But I strongly dislike the way of presenting it when compared to other and their constant misinformation they spread. It may be a great or good product. I seriously meant that part.

If I were in your shoes ATM I would try running the thing. Let us know your unbiased opinion of how you like or dislike it. Not many run them, but this doesn't mean they are totally crap either. I am aiming my harsh attitude at the people and presentation, not nessecarily the product. Your not gonna hurt anything (I don't see how anyways, correct me if I am wrong please someone) by running it and seeing how she performs.

Seriously run it, give us some feedback on your feel of it. I'm willing to bet regardless of your tech knowledge level, you'll be more accurate than their sales team.

Thanks for the clarification - although my response was not just a result of your venting on the advertising lol, but it appears it may not be the right choice as I am not running a MAP but afm with a NEO... but I did buy it opened unused, so paid $50 less than new and have nothing to loose trying it, as I already have it fitted on my piping... I will for sure resurrect this thread when I have it running and can test it... Thanks again

 

[TurboStreetCar]

Yup, BINGO, thats the video I was referring to and I commented about it there too and then a few days later I got this private message from them explaining that the GT4088r is a roots type forced induction.......ummmm noooo, anyways here is the message I got verbatum.


mkrv4jtta

Reply to your comment on: Filtering a Blow-Off Valve (BOV)
Reply to your comment on: Filtering a Blow-Off Valve (BOV)
im not saying its making boost at idle. im saying there is a lot of pressure in the "boost pipes" at idle. the turbos are spinning, pushing air to a closed throttle body, the air cant pass the throttle body nor can it go back to the turbo thats why the bov is open,oh and your gt40,it has boost pipes? right, its a roots blower, and most roots blowers now adays have a "bypass valve" anyways,go check out some vortech and procharged setups or any centrifugal for that matter and see how their dv work


So there ya go, he's not saying that there is boost at idle, but in the video he is saying that the pipes want to explode, and he is not saying its making boost at idle, but he is saying there is alot of pressure in the "boost pipes" at idle........HUH? How does this make any sense at all in anyway shape or form. I've said it before and I'll say it again, it may be a great product, it may not be a great product, but anyone that needs to sell their product by completely misrepresenting other products, spouting completely contradicting and outright wrong info about forced induction of all types, is obviously not letting the product stand on it's own or feel they need to confuse others to buy said product.

Just my opinion though. I've also got some super special snake oil here that when added to your 7m's oil will 100% eliminate the possibility of ever getting a BHG again. How? Well, it's specialized polimer fibro flange electrovibing technology eliminated all possible cylinder pressures normally created and instead cause a vacum to form sucking the headgasket down onto the block hard than any bolt set ever could. The tramorgifying the efficiency of the engine to always be in a vacum state even on the power stroke inversly causing the oil to not-unpressurize and sealing the head to the block. Actually there is no need to even bolt the head down at all anymore with this supra special snake oil. In direct propriatary secret nonidependant testing with leading synthetic cooking oils like pam, it outperformed by a factor of 10 to 1 on the unobtanium flteric idex which we invented to measure just such things so precisly.

Not to defend the product or the company as i also do not like the way the product is represented nor do i like any of the testing BUT, There can be pressure in the intercooler pipes without the engine seeing boost. If the throttle body is closed, or open at a small angle it will cause a restriction to flow. Since there is restriction there is a difference in pressure from one side of the valve to the other. This could mean there is a small amount of pressure in the intercooler pipes but the throttle body isn't open enough for the intake manifold to see boost.

I could see a benefit of the valve being open at low manifold vacuum levels. This "boost leak" that people are making it out to be is releasing the air the turbo is pushing. If that air is released the turbo can spin with less resistance. If the speed of the turbo is high and the air is vented as soon as you put your foot down the valve will close and since the turbo is already spinning, lag could be reduced/eliminated.

If the valve were closed the turbo would not want to spin because doing so would be pressurizing air. When you put your foot down the turbo would have to start from scratch.

This is all theory and the difference it actually makes in the real world could be nothing, but its another way to look at things.

My car is MAP so i have my blow off valve set very loose and open to atmosphere. Its a Greddy type-RS and it is JUST open at idle. I have it set this way because if the manifold vacuum is at that point i dont want any boost in the intercooler pipes anyway. It also goes with the above theory that letting the pipes vent and the turbo spool in part throttle will benefit in spool up time at speed.

Another point about how much air actually moves threw the pipes at low RPM and load. When i first installed the BOV and i was adjusting it, a light quick rev to about 2.5-3krpm resulted in a VERY large and high velocity charge of air from the blow off valve. The thing that makes that interesting is i have a 70mm turbo that doesn't make any real boost until about 3500-4000rpm with anything less then 80% throttle.

 

[IJ.]

<nodding> My T04z is moving a lot of air even at idle being a roller bearing turbo.

Boost pressure = resistance to flow, you won't "see" pressure until the Turbo is moving enough air to exceed what the engine can ingest but that doesn't mean the turbo is moving nothing up to that point.

I know my car even at 1psi is so much more powerful/responsive than if it runs with the charge pipe off.
(MAP based so I've driven it a few times this way)

 

[teedoff00]

Well my set up with the new fitting didn't work, I still saw a significant amount of surging. I have plumbed it up yet again, this time eliminating the pos 22 dollar reducer I bought, and installing a 1.25" hose from the Recirc. fitting to the 1" ID 45 degree fitting I siliconed into my accordion tube. I haven't had a chance to test it yet due to bad weather yet again, but tomorrow hopefully I will be able to report back with no surge and pictures of the setup for reference.

Wish me luck, cuz if this doesn't work, I don't know what I will do...

 

[Flateric]

Sounds to me like you have things under control and will get it figured out though.

Good luck anyways.

 

[IJ.]

Something to keep in mind when plumbing a system is a single 90 degree bend is roughly equal in flow resistance to a 10 foot length of the same diameter straight hose.

 

[TurboStreetCar]

Is there a matter of velocity with that Ian?

 

[IJ.]

Yes it will slow as it hits the bend and depending how prone to surge a particular turbo is it may tip it into surge no matter what you try.

 

[turboguy327]

What about having a large hose as a "tank" of sorts for the boost pressure to fill up as it vents so it has a cushion to overcome the restriction or the 90*??

 

[teedoff00]

So after some testing today... I have decided it is much improved, but I don't think the surge is completely gone, don't get that even pust sound that I did with no recirculation. I don't know whether to leave it as is (is a little compressor surge going to fry my turbo fast? Not sure if it is quantifiable.) or try to go up to a 1.25" 45 degree copper fitting. I really don't wanna cut the other one out, widen the hole and massage the massive 1.25" hydraulic hose onto it, but I guess if the small amount of surge I am getting (will have to post a vid and see what you all think...) will give me wicked shaft play in under 3 years, then I will have to do just that.

Current set up is: 1.25" Synapse BOV Recirculation Fitting --> 1.25" Gates Vulco Hydraulic Hose --> 1" ID 45 degree copper pipe (the flanges are like 1 1/8" so they can be brazed together if that makes sense.)--> straight into the accordion hose.

Here are the pictures, let me know what you think...