Anyone running VTA? Anyone advise it?
#1
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Anyone running VTA? Anyone advise it?
Hey guys,
Should be picking up the base Greddy soon.
I am still debating whether to run it stock with no BOV, maybe find a used I/C that has a BOV or try install a BOV on the intake pipe.
Is anyone runnning a BOV that is VTA? Any problems with it?
Thanks
Should be picking up the base Greddy soon.
I am still debating whether to run it stock with no BOV, maybe find a used I/C that has a BOV or try install a BOV on the intake pipe.
Is anyone runnning a BOV that is VTA? Any problems with it?
Thanks
#13
89, most of those guys saying they have no problems are running some sort of aftermarket engine management.
Running VTA on a 1.6 w/stock ECU and no engine management, you will have problems during shifting, or potentially simply during lift throttle situations. At freeway speeds, 70-80mph, you're running in the 3000-3500rpm range, which is where the Greddy turbo starts to spool and make positive pressure.
The problem with VTA is that while cruising at those speeds, with the manifold in vaccum, the slightest breath on the pedal will start to spool the turbo, so you'll lift, and vent, and the car will run crazy rich and buck. With my T25, which starts to spool around 1800rpm, I found it IMPOSSIBLE to drive smoothly on the freeway. I was always in that grey area with the mani in vacuum and the turbo making about .5psi, not enough to close the BOV, and simply VTA'ing the .5psi.
The Greddy spools way later than that, but the potential is still there to have cruising problems, even if you go with a fancy no-leaky BOV. If the cool sound is worth the tradeoff in potential problems, then go for it. But you are pretty much guaranteed no problems if you recirculate.
Running VTA on a 1.6 w/stock ECU and no engine management, you will have problems during shifting, or potentially simply during lift throttle situations. At freeway speeds, 70-80mph, you're running in the 3000-3500rpm range, which is where the Greddy turbo starts to spool and make positive pressure.
The problem with VTA is that while cruising at those speeds, with the manifold in vaccum, the slightest breath on the pedal will start to spool the turbo, so you'll lift, and vent, and the car will run crazy rich and buck. With my T25, which starts to spool around 1800rpm, I found it IMPOSSIBLE to drive smoothly on the freeway. I was always in that grey area with the mani in vacuum and the turbo making about .5psi, not enough to close the BOV, and simply VTA'ing the .5psi.
The Greddy spools way later than that, but the potential is still there to have cruising problems, even if you go with a fancy no-leaky BOV. If the cool sound is worth the tradeoff in potential problems, then go for it. But you are pretty much guaranteed no problems if you recirculate.
#14
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It takes more than breathing on the pedal to get the base greddy to make positive pressure under 85 mph in 5th. May be of concern with a good aftermarket exhaust, but not as a stock-ish greddy system.
Your T25 spools earlier, not to mention your BEGi mani and dp are going to breathe better.
I find the BOV 'wooosh' interesting. It sounds *completely* different with the AFM out of the intake tract, too...
Your T25 spools earlier, not to mention your BEGi mani and dp are going to breathe better.
I find the BOV 'wooosh' interesting. It sounds *completely* different with the AFM out of the intake tract, too...
#17
I had the greddy kit stock with just a bailey VTA BOV for a while with no problems.
The bailey is quick and thats what you want if you still have a MAF.
Also with the bailey you can mount it on the stock crossover pipe so if you got limited funds you can just slap it on there and you'll be good to go.
I have herd good and bad things about all other BOV's especially the Ebay knockoff brands so the bailey is my only recomendation. I should be there spokes person er' somethin?
The bailey is quick and thats what you want if you still have a MAF.
Also with the bailey you can mount it on the stock crossover pipe so if you got limited funds you can just slap it on there and you'll be good to go.
I have herd good and bad things about all other BOV's especially the Ebay knockoff brands so the bailey is my only recomendation. I should be there spokes person er' somethin?
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