Mikerock

iTrader: (6)

Hey guys i was looking for some help. i Just recently did an intake, bov, turbo back exhaust. got it tuned, and now when im in 3rd or 4th gear at 3k rpm the bov will vent and i will loose boost all the way up to 4k 4.5k unless i put my foot in it. however when i have my foot in it and shift i get flutter.

I was wondering if anyone has any insight or could point me in the right direction to tuning the bov on my own, i originally wanted it tuned on the dyno as well but i guess it wasn't in the cards.

perrin intake, perrin bov, perrin turbo back, 26lbs of boost.

i appreciate any help!

F0RSAKEN

iTrader: (34)

Your HP seems awful low for 26lbs of boost.... How much boost are you running when it flutters, and what kind of boost control are you using?

I have an EBC, and I'm pushing ~20 psi around 3.5k-4k, and if I'm not WOT, mine will flutter too (TiAl BOV). I don't think there is a fix other than factory ECU boost control with an aftermarket (AEM or something similar) setup for load based boost.

Mikerock

iTrader: (6)

boost when its fluttering im not sure, ill keep an eye on it though. Im using the hallman manual boost controller. i understand the flutter could be the bov and not necessarily the turbo, but when it vents at 3k the boost just drops... its like i hit a flat spot.

yahu

iTrader: (55)

I'm not sure I completely understand your problem, but realize when you aren't "committed" to throttle (half-throttle, for example) vacuum will tend to try and take over. A lot of times the flutter you hear is sealed-vent-sealed-vent etc. (or recirc, if you are running that). With some BOVs, like a TiAL, you have a diaphragm that might amplify that sound.

You are saying that when you're at WOT and shift you hear flutter? The stock IX turbo will kind of sound like that when installed backwards.

If the TBE, bov, intake, and mbc are your only mods, that isn't too low a number at 26psi btw, especially if you don't know how many * of timing you're running. Josel just made a similar figure with those mods + intake long-route intake piping on ER's dynojet running pump, and I believe there are similar modded folks out there in that same range. Did you get tuned at ER? Have you asked your tuner about this?

*edit - also, I'm not really sure what you mean by tune the bov, unless that is something specific to the Perrin (not familiar with that one).

F0RSAKEN

iTrader: (34)

I didn't see a fuel pump in there, and without that, his numbers are right where they should be I suppose lol.

The BOV may have a tension spring, where you have to set it to the appropriate pressure depending on the vehicle/boost/etc... it's used on. Some are like that, not TiAls though.

And what I think (i.e. got) from his question is pretty much exactly what my car does: If I'm accelerating normally, or slightly better than a grandma, and I take a gear, say 3rd, past 3500 or 4k, I start building boost WAY too fast and it causes odd turbulance in the IM, creating a on/off of vac/boost which rapidly opens and closes my BOV.

I talked to R/Ternie about it, and he advised I go with an AEM boost solenoid, and have my boost tuned accordingly... or buy a bigger turbo that doesn't spool up as fast. I like option 2.

yahu

iTrader: (55)

LOL - option 2 is good. Good point on the walbro, but I think Josel even had one of those. Did you get tuned before upgraded IC piping? I know those can have an impact, even moreso when you go short route. Realize stock these cars are doing 230 - 240whp on the dyno so a gain of close to 100whp is outstanding for so few mods (really only 2 power mods for the OP, and 2 boost mods, which obviously can also have an effect on power).

BTW - the TiAL 50mm does have tension spring and you can go with softer or harder springs, depending on your vacuum at idle. E.g. - I have a -11psi spring that causes the fluttering in low rpm when I don't go harder throttle, especially in higher gears (5th and 6th). For my vacuum at idle, I should literally be at the -7psi spring. I worry that will be too soft though and cause a boost leak at the BOV. There is a -9psi spring as well but I don't want to drop $30 for each spring! And I'm lazy.

Mikerock

iTrader: (6)

Yes, when half throttle, even less really. the bov will vent and recirculate causing it to loose boost, watching the boost gauge it slowly builds more vacuum. 3/4 throttle or when im in boost and shift between 3rd and 4th it will flutter.

THe hp i think is right about where it should be, i don't have upper or lower pipes, just the stock ones, no fuel pump, just these things. When im in boost and on the throttle it makes the power its supposed to make, but it seems like its all or nothing.

As for the perrin bov, the cap is adjustable for spring tension, and there is a screw inside that is adjustable for flow. It can be adjusted depending on your set up. I just don't want anything to explode or burn up, it being a daily driver ya know.

F0RSAKEN

iTrader: (34)

Yeah, he's where he's supposed to be considering the mods, I read more into it than there was. I have 2 springs for my TiAl, both do the same thing (9lb and 11lb), It's just that the stock IX turbo spools so fast even at part throttle that you can't really control it with an MBC or even an EBC, at least not in a way as to prevent the fluttering.

I've been doing a lot of thinking on it, and eventually I may test some things to try to alleviate it, but short of load based boost control or a slower spooling turbo, I think you're as stuck with it as I am.

I've also wondered a bit if something like Dan's Magnus or an AMS cast mani may help stop the fluttering too, maybe with a larger TB too. The design differences over stock may not cause the fluctuations that the OEM mani sees. Just speculation though.

Ryan.Kauz

iTrader: (11)

I've never heard of installing the turbo backwards.

mikiblueeyes

iTrader: (7)

Stock Fp can support about 350WHP as well as sotck injectors wtih other supporing mods, I had it on my car back in the days. We usually change FP to walbro just to be sure of solid fuel delivery at those power levels.

M8NSTER

^+1

You need to upgrade to a walbro 255lph fp.

$100 and takes 30 mins to install.

More boost requires more fuel!

I'm not sure what's causing your problem, but without a fp upgrade you'll run lean which will cause knocking (bad!!).

RoninVIIIRS

iTrader: (9)

If you are stepping on the gas half-assed. Does it even matter what the boost is doing at 3k? I mean you are just crusing at that point and most likely in vacuum, I don't see it being relevant especially if you say it's ok at WOT. As for flutter, aftermarket blow off valves really do make all sorts of noise. I think if you did your boost leak, and your tuner tuned the car and didn't notice a problem........It doesn't sound like you have issues.

yahu

iTrader: (55)

^maybe that is why I'm having a hard time seeing the issue? There isn't one?

Oooh, TiAL 50mm? If so, are you using the -9psi spring? If not, can I barrow it? If it doesn't fix my problem I'm going with the -7psi spring. At -11psi - -13psi vacuum at idle, or so, the -7psi spring is technically where I should be at.

LOL - meant the stock IX BOV.

jaymzz

iTrader: (4)

I had a Perrin BOV on my Evo and had the same issues. Take it off and throw it away and that will solve your problems. When I first put my Perrin BOV on it ran like that and I took it to Perrin for Jeff to look at and he did some adjusting on it but it didn't help to much so I put a stock BOV back on and all my problems were solved. I did have a few people try to adjust it but never had much luck.

Mikerock

iTrader: (6)

Well i don't drive at WOT everywhere i go, and i know enough about it to know when rpm's go up so should the boost, not down. its about drivability not awesomebility. p.s. if i could drive at WOT all the time i totally would. Im just going to sell it, plus i still have the turboxs VTA one that was on it. the car ran better with that anyways.