TTP Engineering

iTrader: (465)

That rule of thumb looks fine.

WagsEvo

Just installed mine last week after quick shipping from TTP (THANKS!). First impression is that this DV opens a LOT faster than stock. I feel boost response much quicker between shifts. It is a little louder than stock, but I think that's just because it opens and dumps the air much faster.

I also have some driveability issues at part throttle. It seems to open too easily and the Evo bucks after losing boost. I'm on the blue spring now, so I'll switch to the red at 20-21 psi and see what happens. I'll post results.

Thanks again to TTP for a good price and quick shipping .

shivaswrath

iTrader: (9)

Any news on the red spring installation? Want to confirm for those that are getting this DV so that they won't have to worry about part-throttle issues. . .

WagsEvo

Sorry - haven't had time to make the switch yet. I've been adjusting my driving to deal with the part-throttle issues.

I'll try to find time this weekend and post results. It will really only take 20 minutes.

coffeeslug

iTrader: (6)

There's no spring or spring and shim combo that will completely eliminate the flutter.

TTP Engineering

iTrader: (465)

If you want a BOV that doesn't flutter, buy a stock plastic one complete with air leaks.

People just can't understand that the reason stock does not flutter is because it is designed to leak.

If you want to stop leaks, you will face part throttle flutter no matter what the valve.

Flutter means the valve is stiff enough not to leak under boost.

WagsEvo

I understand there will be some flutter. Like it was said, this is the price you pay for holding boost at higher load. The question is what combination of springs/shims will be right for each car to reduce the flutter.

UPDATE: I switched out the blue spring in my Evo15 for the red spring plus a shim and the driveability is MUCH improved. No more opening at 2 psi and jerking the car. The trade-off is a partial boost flutter that sounds a bit strange, but is almost not noticeable during daily driving.

My relative mods: TBE, MBC at 20-21, intake and full IC piping.

On a side note, I've now developed a new boost leak somewhere because this DV holds so well. It's always something...

evoski

iTrader: (2)

I also just switched out the blue spring for the red one, no shims. I am currently running 22-23psi. When the bov releases under partial throttle it sounds like it is laughing at you, a little annoying. It does hold boost better at partial throttle though if you can get past that sound.

yikez

iTrader: (2)

^
you may have the DV backwards then.

Liqquid

Open the hood and kick it's ***!!!!


I just got mine a couple days ago, car hits alot harder than with the plastic, I've got the red spring in there for my race gas map, the only thing so far I've noticed is in 5th on the highway, if I hit the gas into boost then let off quick it bucks the car, but all I have to do is push the cluctch back in for a sec to slow back down and I'm good.

evoski

iTrader: (2)

I did that, its not laughing anymore.

EJEvo

iTrader: (18)

I've got a Forge DV (whatever one LancerShop.com sells) on my '03 Evo VIII. From the springs I have left over, I must have the blue spring in and maybe a shim or 2. I've got a Forge MBC and I'm around 24-25 psi.

I took the Evo to Watkins Glen on Monday and Tuesday, and I had a bear of a time under partial throttle, especially in the Esses (Turns 2 & 3) and Turn 5 (just after The Bus Stop). The car just kicked so much under partial throttle that it was a bit difficult to drive it smoothly, and I'm guessing that bang-bang-bang flutter can't be kind to driveline components.

I'm back there in August and September and will definitely try the red spring. Thanks for the suggestions here.

MitsuJoe

iTrader: (133)

And I was looking at replacing my TurboXS with a forge. If the flutter is meant to be then my recric TurboXS valve fits the bill.

TTP Engineering

iTrader: (465)

TurboXS blow off valve is one of the worst we have ever tested.

EJEvo

iTrader: (18)

I've switched in the red spring (no shims), and so far on the street flutter is non-existent. I'll report back at the end of August after another Watkins Glen encounter.