Setting Up The Turbosmart Dual Port BOV

[RichB]

See my other thread, I'm in the same boat. When I got my turbosmart, SU had already set it to the right tension for our cars. It worked great. I ran for two or three moths without issue. Recently I have occasionally heard the *pop* of a very small backfire. Quite infrequent, maybe once a week and usually with colder weather. I have tightened my cap a quarter turn, and hopefully that will fix it.

I have always had smooth, even, pssssshhhhh release in every gear, with no flutters or pinging.

I am considering recirc, but some folks at work confirmed that the hybrid sound is badass, and it performs very well at holding boost; quick to spool and hit 16 and hold it at 15 psi while you're mashing it, in all gears.

Glad I went with this valve, it's def. mad science.

Yea I was like you. It was set perfectly from SU but when I got a turbo inlet everything changed. It took me like a week to come up with a good method to adjust this thing. The turbosmart directions were useless to me. I turned the valve to the loosest setting and didn't notice stalling or a rough idle. Now that I found a method that works I figured I'd post it since it applies to any added mods.

Since I got this valve I been breaking my tires loose a lot easier. The sound is awsome but it did get quieter with the turbo inlet.

With all the configuration possabilities and how well this valve works, I feel that it is money well spent.

 

[ElSpeedDiablo]

Well I bought my used from the forums, the guy says he has the trumpet off, it's set on full recirc. So I thought I would just have to take off my forge and bolt, so are you guys saying I will have to still mess around with it to set it right? I have a Cobb SRI and Turbo Inlet. Thanks!

 

[RichB]

You might have to. I have noticed that the turbo inlet drasticly changes the settings.

 

[hugador]

Got mines today. SU black out compact dual port bov. Intall it on a stock 2009 MS3 and definitely notice an improvement.

One of the questions people have is does it work, does it hold boost longer and answer is a big loud YES!!. Your not spending money on this thing just for the psshh sound - which is comfortable loud - but for performance.

Out of the box (which is set 50/50, SU recommends) with out adjusting it, it sounded fine. I did a quick rev and car din't stall or any backfires, it did its psshh sound so I went out for a drive. Notice that there was no psshh sound in first gear, little bit in second and getting louder in third and up. Maybe set too hard so I soften it a bit in quarter turn increment like RichB said and that did the trick. I get the psshh sound on all gears and car is moving faster than when it had the stock bpv. I soften it just a little bit more like 75% from a half turn to where it was set out of the box. Went for another spin, cops all over the place, wich is okay they are my compadres lol, car keeps getting faster with no backfires or stalling, so I kept it there for now. I think I can go softer but i'll wait until I break it in a little bit. Like RichB said it's gonna take a little while to fine tune it. So far so good.

 

[hugador]

Okay, so I played with it a little more today and could not adjusted it any better. It's kinda hard doing this by feel than with a boost gauge or DashHawk. But definitely an improvement. I replace the factory hose clamp that secure the vacuum hose onto vacuum nipple with one of those that you tighten it up with a screw driver or socket for maximum grip. Because I notice that with the factory clamp will leak if you put your finger on top of it and gave it some pressure while the engine idles(duh).

 

[RichB]

Ok I tried something today and I thought I should share my results.

This morning I reconfigured my valve from 50/50 to 100% recirculation. I didn't adjust the spring at all and just drove it as is. My butt dyno noticed a lot less lag especially between gears. Throttle response was much crisper.

Anyone else want to try this and confirm my suspicion?

 

[MSMS3]

I think you are right.

This is not a track slip. But this attachment is from the data print outs of a tool that has typically been within one tenth of a second of the track timers on several different vehicles.

I think it is a bit better than a butt dyno. So, 13.5's at 107 on the stock BPV. This is on stock tires. Launch is still a bear to get right. The 107 will seem to be about one mph high, because this accelerometer measures absolute speed at the end of the quarter mile, while the timing lights on the strip measure trap speed as a average over the last 66 feet

I was running 14.0 to 14.1 at 103 on the same instrumentation before installing the catless DP/RP.

Runs were made by feathering first gear and the transition to second, and then flat shifting 2-3, 3-4 and 4-5.

I don't think I would get any benefit from any BOV or from a new BPV, especially not one that is not full recirc.

I want people to see my tail lights and don't care what they hear -- the less the better, as far as I am concerned, but that's just my personal preference.

 

[RichB]

I definitely felt a difference after taking out the stock BPV. I started out with a Forge and I noticed almost no lag. I press the gas and the turbo responded. Same thing with the Turbosmart.

In between the Forge and Turbosmart I had the stock one back on for about a week and I definitely noticed a difference in Turbo lag / throttle response. my turbo simply spooled faster with an aftermarket valve, which I confirmed with my boost gauge.

In recirc mode the Forge and Turbosmart perform the same. The only difference ofcourse was the sound.

 

[MSMS3]

I'm confused, RichB. Your two most recent posts seem to contradict each other in some ways. Maybe it's just me, I apologize. It seems like you were saying that switching back to full recirc with your Forge produces a much more responsive turbo with less lag than running it 50-50. With that observation, I think you are right.

But you are saying that the Forge running recirc is more responsive than the original BPV with less spool up time. How do you reach that conclusion? Are you talking about part throttle response at low rpm, or at WOT, or when?

I posted the G-Tech Pro chart (not to be taken literally as the equivalent of a drag strip run, but a useful tuning tool that is eerily close to strip slips), to point out that there is absolutly no discernable turbo lag with a properly functioning stock BPV.

Here's another of the data charts compiled from that run. This one shows maximum g forces versus time. Note that there is an instantaneous .5 g's at launch, during constant wheelspin leading up to the .6 maximum g's in first gear, reached in .9 seconds.

At that point traction decreased a bit due to continued feathering of the throttle to regain maximum traction before the shift to second gear. Then, you'll see that wheelspin again entered the picture in second gear, requiring more feathering of the throttle. All of this happens in 1.8 seconds.

In 3rd-5th gears, g's naturally decrease due to the decrease in gearing ratio with each change and the increasing effect of external ballistics - aerodynamic drag goes up as the speed increases and it gets increasingly more difficult to punch through the airstream.

 

[RichB]

No I just reconfigured my Turbosmart from 50 / 50 to full recirc. When I did that I noticed quicker throttle response from a rolling start.

I also said that my Forge had a quicker response from the same rolling start than the OEM valve. I felt the same phenomenon when I went from the OEM valve to the Turbosmart in 50 / 50 mode.

Does that clarify things?

 

[MSMS3]

Does that clarify things?

Sort of. Thanks for the explanation.

By rolling start are you saying first gear at 5 mph, like Car and Driver uses for their 5-60 mph test, or are you at some higher speed when you start the roll?

And do you go WOT from this rolling start?

Did you measure the time for spool up with each?

This is going to be happening very quickly, either way, would it not?

I can do the accelertion runs and data log from the accelerometer from a roll and give you a base line for the stock BPV from any speed you want to start the roll, if you are interested in being objective, but I can't tell you how much quicker or slower your BOV would be.

All I can say is that from a dig, where I'd think any boost lag would be the worst, the g force rise is damn instantaneous.

The problem does not seem to be boost lag -- it is poor traction from our setup with fwd and the unloading of the front suspension with weight transfer to the rear on launch, away from where the weight is needed. And you can't get full power in the first two gears anyway because of the torque control built into our ECU.

 

[hugador]

I definitely felt a difference after taking out the stock BPV. I started out with a Forge and I noticed almost no lag. I press the gas and the turbo responded. Same thing with the Turbosmart.

In between the Forge and Turbosmart I had the stock one back on for about a week and I definitely noticed a difference in Turbo lag / throttle response. my turbo simply spooled faster with an aftermarket valve, which I confirmed with my boost gauge.

In recirc mode the Forge and Turbosmart perform the same. The only difference ofcourse was the sound.

Yep, aftermarket is the way to go. I'm glad I went with dual port. Car perform better than stock bpv. I have it set to 50/50 with no problems. And the sound is awesome but thats least important. I'll probably try recirc mode but why fix something thats not broken. lol

 

[RichB]

Yes I was talking about a 5 MPH start MSMS3. It might not be turbo spool because it is fast anyway like you say but there is definitely something different that I can't put my finger on. I am sucked into my seat a little more. I wish there were an easy way to confirm this other than my Butt dyno

 

[MSMS3]

Understood, RichB.

Some things we can measure, some things we cannot. The "joy factor," or "fun factor" can't be measured. These are great little cars. Modding and personalizing the cars for our own individual taste makes it even more fun.

I guess there's just too much "prove it by numbers" in me. I'm an old (literally) drag racer, whose been racing NA and turbo cars for many, many years, and who grew up in a family business (still going) that builds racing engines. Now, I'm a lawyer for my day job, but I still have grease under my nails from grinding crankshafts, boring engine blocks, line boring main bearing saddles, milling cylinder heads and all of that when I was younger and active in the family business.

But the thrill of putting a light small engined basically stock car easily in the 13's on the strip and maybe the 12's with few mods, but with attention to detail, is still in my blood.

BTW: lets all keep our racing on the strip and our performance testing on private road courses, and play safe. The life you save might be . . . . mine!

 

[RichB]

I bet if torque were plotted out, you would get the same peak with a slightly different slope. That is what it feels like anyway

 

[SubieKiller3]

ok so i just got my turbosmart dual port today from SU. i hear it is suppose to come already setup for my car, but lets say i wanna fine tune it. what exactly should i be monitoring on the dashawk other than the boost psi?

 

[RichB]

AFRs would be good to look at if you have it set up in either 50/50 or VTA. If the values dip too low for your comfort in between shifts, just tighten up the setting until it is where you like it.

 

[SubieKiller3]

sweet baby! just put this thing on today and i love it. holds boost like a champ and sounds great. curious to see the difference it makes in full recirc. might play around with it and see but i will prob leave the horn fitting on anyway because it sounds so good. can always just swap it out when i go to the track.

 

[macdaspid3]

Ts Bov

I've seen a lot of questions about how to properly set-up the Turbosmart Dual Port Blow Off Valve so I thought I would post how I did it. It will take a few trips down the street but I feel that my method to be pretty effective.

I started out with the hardness right in the middle. To set this, you tighten the knob all the way to full hard then loosen it three full turns. With this setting, go for a test drive and listen to the valves operation. You should be getting a nice even release of air with a 2nd gear WOT pull (pick a good road for this and watch the speed limit). If you are getting a fluttered release, loosen the valve in quarter turn increments until you hear the right valve release. When you are satisfied, take it out on the highway and go through the gears and listen to the valve (again watch your speed). This is a good time to take note of your max boost pressure if you have a gauge. If everything is set right, all gears should have a nice even release and your max boost pressure should be normal and holding. At this point, you can make minor adjustments to dial it in right where you want it.

Note 1: You only have six full turns of the knob from extreme tight until you see the red indicator mark for max softness.

Note 2: You should get some valve flutter with partial throttle releases.

Note 3: After I installed my Turbo Inlet I had to loosen my valve setting at least two full turns for proper operation.

Hope this helps people out.

Did you set it at recir mode (by replacing the horn with the blanking nut)? I think mine running really rich with the horn, black residue coming out of my exhaust when revving.

Thanks,

 

[RichB]

Thats just a typical MS3. You're fine if there's no backfire or popping