kevincnc

Hey guys,
I'm not looking to start a vendor war here, I'm pretty fully vested in my setup and not really considering anything other than an upgrade.

I'd be interested in hearing FIRST HAND feedback on performance improvements going from the older standard MAF setup to V-Flex/V-MAF+. I understand the safety aspects, but am interested in any differences in lower end torque, spool-up, etc.

Thanks in advance for any informed feedback.

Adonay

I would also like to know that...

Techno Duck

I have been running it since June, have about 2k miles or so with it. I have not been able to really best its full potential yet due to sorting out some issues with the car (not related to the MAF setup). I finally figured everything out and hope to finish tuning the car this weekend, will be doing an auto-x this weekend and a few driving events before winter hits.. so should be able to give better feedback in a few weeks.

I can say that the low end spool is better thanks the timing control. I cant put a number on it, but it is noticeable. The tuning with the new SMT8 based software i think is also much improved over the SMT6, the ability to adjust fuel based on boost i think is a big plus. Another big plus is it is USB 2.0. I never liked the SMT6 because it was always very sensitive to drivers due to the serial connection. This was mostly an issue using it on newer laptops that do not have serial ports.

If you have any more specific questions i can try and answer them.

marcoturbo

I can't tell the difference between the "standard" MAF and the v-flex (other upgrades have been installed with the v flex) but I know it has prevented my engine from blowing (thanks to overboost protection) when the wastegate has been lined up backwards...

kevincnc

Thanks guys, anyone else? I don't see how the SMT6 would be able to control fuel based on boost. I guess that's a question for John. Techno Duck- did you have to alter the timing through the PB or was the control from the new software good enough to be noticeable? I don't have easy access to a dyno, and not sure I would be qualified to mess with the timing myself anyway..

Bri Bro

Like Jon stated, I notice a difference in low end response. I changed too much to tell anything about boost response in a before/after the software change test but I am spinning the tires all the time trying to tune the GD thing. I also go to the track in a week, more to come.

Richgreenster

I use the smt-6 with V-Flex with an electronic boost control selenoid to control my wastegate. If you are using another means to control your wastegate then I really do not think that V-Felx will give you any noticable improvements on the lower end. John can correct me if I am wrong but his non V-Flex is almost spot on. In fact, I ran Vitesse without V-Flex for a long time and did not switch over until about 3 months ago. The car ran so good that I really did not see a need until I started to turn up my boost. I really like Johns set up with V-Flex for the safety factor and I love how the smt-6 controls my boost. Totally hidden and very easy to change.

I plan on getting my car on a dyno this spring and switch over to a different map on John's chip. One labled "Only try on a dyno /less agressive timing". I assume that this would be the biggest factor to what you and I am after.

kevincnc

I have a Profec B for boost control, but would let the PB control it if I upgrade. The non V-flex is doing fine, I just would like to have better low end power and quicker spool. From what you guys are (mostly) saying, it sounds like it could do that for me. The SMT8 has a lot of nice features, I just don't know if it's worth the extra money since I already have the 6. Maybe a 3" exhaust would do more good, I don't know.

Richgreenster

The 3" would help out big time. If you want less turbo lag and faster spool up, I would get a different turbo, have some head work done and try a different cam. Also the exhaust system would help a bunch as well. 3L motor is also a fix for low end torque.

I know a few on here have used a duel system to create boost without any load. You could go to that.

Just courious as to why you want faster spool? Auto-Xing?

kevincnc

Doesn't everyone want faster spool? I live at 7000+ feet so I'm sure that makes it worse. I don't know of a turbo that will spool significantly faster and give me as much power- maybe a gt3076R but that would be a last resort as would be head work or 3L. How does a dual system work?

Adonay

I use the vflex with the boost control option on my car . I had a Profec type S but sold it. Adjusting boost and spoolup with the Profec is way easier. But when you get the piggiback correctly set you wont ever have to touch it. but if you have to change something other than the 2 maps you have its a PITA as you need a laptop. Sometimes when i was trying to get better spoolup i wished i had kept the Profec.

If you want faster spool make sure you exhaust is a 100% leak free before the turbo . I thought my manifold was in great shape turned out it was not. Same goes for Crossover .

Thom

Whether the engine will necessarily turn earlier turbo spool into torque is not a given.
It all depends on how exhaust+turbo+IC+intake are balanced together, big can of worms...

slivel

My setup is an 89 with stock displacement and cam, 3" exhaust, manual boost control, dual port waste gate, SFR stage 1 headers, turbonetics 61 BB turbo, Vitesse stealth MAF and PB, WB O2 sensor. I had run the Vitesse MAF and PB for about a year before upgrading to the V-FLEX. No other mods were done at the time - just the upgrade to V-FLEX. My impression is that spool is slightly faster with the regulated ignition. A previous poster mentioned that he didn't see how the SMT6 could control the fuel based on boost. John should chime in here, but my understanding is that it does not control fuel based on boost, it controls the fuel based on load (volume of air from MAF output voltage, rpm, engine temp, throttle position). The addition of the MAP sensor in the V-FLEX upgrade is used to control the ignition timing. If my understanding is flawed, someone please correct me - I'm always looking to improve my understanding of these devices.
Two thumbs up for Vitesse products and service.

jasonlp

It's not worth the money for your setup

Try cleaning out your IC and ditching the bottleneck rubber hose from the IC to turbo

kevincnc

I think you're right, but the SMT8 allows you to control fuel based on boost also, which I think would be useful since load varies from gear to gear.

You think my I/C needs cleaning after 40k miles? I suppose it could. I'm sure it would help most to just ditch the whole "stealth" setup, but I'm not ready to do that.