problem with tial BOV/wastegate

[somedude_001]

2 days ago I was driving around and my car was REALLY fast and after a while I looked at my boost gauge and hit it. well lets just say the gauge was way past 8psi, and I noticed when I let off the gas the BOV sounds different. normaly it is just a pop pssssss. well now it flutters. it sounds amazing but I am a bit confused as to why it has changed sound.

let me go back to the over boost which was interesting to drive. at half throttle in second it would build 15psi with the quickness. any more throttle and the gauge would almost instantly peg and would blow out spark. yes i'm still running .035 gap. seems it would blow spark at around 17-18 psi but these were very short burst of throttle. i don't want to run that much boost though because in all serousness the car is scary to drive. first is completely useless second is ok at 1/2-3/4 throttle and i never went past that.

now I instantly though oh i must have a hose problem and the line to my wastegate must have some how come off or have been damaged. so I put the car in storage for the night. I pulled it out last night and the car was completely normal. BOV sounds normal again, and i'm only boosting to 8psi. also the massive low end power was back to normal. the car would almost instantly build boost from a stop and that is back to normal. So that confused me a bit. but the only thing I could think is that line from the wastegate come off (which has is T'd from the BOV line) so I though there might ahve been a disturbance in the line causing the new sound. well to complicate things further the BOV changed sound back to the flutter sound but I only build 8psi like it is soposed to. nothing has changed I'm a bit perplexed as to why the sound would change. personaly i like it but I don't like not knowing what it going on.

so when it warms up i'll be tearing into this thing again to figure it out. maybe we will do the 4" intake at the same time.

 

[1slickRED89]

Sounds like the wastegate line might be acting up. I know on my car I have a direct line with no other interference and it still acts funny. I was going to increase the line size from 1/8 to something bigger to get rid of some goofy harmonics.

also i'm sending out those modified AGSF12FM1 spark plugs this week so you should be good, so long your wires are OK.

 

[somedude_001]

i will try running the WG from the turbo housing rather than my manifold and see if that changes anything that would redice the holse length from 4 feet to about 6 inches. It probably wouldent hurt to upgrade my line size either. There is a lot of hose that has to go from boost to vaccume. from manifold to BOV (LF bumper) T to wastegate (rf bumper)

my plug wires have 30K or so on them. but they are taylors and seem to be doing well.

 

[1slickRED89]

Sounds like it's worth a try. but referencing it at the manifold should work too, so there may just be a physical problem the line.

on page 147-148 (figure 12-16) in maximum boost they talk about the advantages of referencing the WG at different points in the system. might be worth the read if you haven't read it yet.

 

[somedude_001]

i referenced it at the manifold so I could get more boost out of the same spring. I wanted 10 PSI at the manifold with my 10psi spring (which ended up being 8 after a couple of weeks). I never put a huge amount of thought into it.

no I have not had the pleasure of reading that book.

 

[TT SHO PROJECT]

the bov "Flutter" sound..... my bov does this when i up the boost... low boost its a crack Shhhhhhh sound... high boost its a Crack SHHH SH SH SH SH SH SH... its just how the bov is made... bov's for maf cars "ie my Turbo Xs RFL bov" they shutter so it doesnt confuse the computer as much... instead of dumpng everything at once it lets a lil out at a time.. the higher the boost u run the more shutter you will get... so ill say its normal. you Maybe be able to change it by adjusting the spring in the bov IF thats an option for you... mine i just unscrew the top and add a spacer washer or 5 depending on what i want/need.

 

[adidas_kn]

On my turbo car when ever it makes that different sound it is not the BOV. It is the BOV not opening in time(in sync with the throttle blade) and the turbo choping the boost up till it is able to be released. it happens when some BOV's aren't setup for the increased boost. I forgot the name of this though. It is bad for the turbos bearings and compressor wheel. Your wastegate is probably sticking allowing more boost than normal and the BOV is responding accordingly.

 

[somedude_001]

you hit the nail on the head. the BOV was not opening properly. I lubed it up and dissasembled my wastegate today (which for some reason is missing a bolt) and all of my vaccume lines were ful of water? I also moved the wastegate signal to the turbo housing and now it only makes 5psi of boost so i'm going to put that back on the manifold. the car is very boring to drive now with it like this because the boost builds much later and slower.

On my turbo car when ever it makes that different sound it is not the BOV. It is the BOV not opening in time(in sync with the throttle blade) and the turbo choping the boost up till it is able to be released. it happens when some BOV's aren't setup for the increased boost. I forgot the name of this though. It is bad for the turbos bearings and compressor wheel. Your wastegate is probably sticking allowing more boost than normal and the BOV is responding accordingly.

 

[adidas_kn]

Yeah I know. I have owned many a turbo car. Gotta know what your dealing with. Good luck with that. Still tryi to decide if I should go the turbo route or the supercharger route. I don't like the possiblity of a slipping belt but the Rotrex S/C can handle the high power capabilities and builds boost like a turbo. Also it is smaller and easier to package.

 

[somedude_001]

I can tell you before I cracked my exhaust before the turbo the car can be scary to drive. it really makes you prey for AWD.

 

[SHO92]

When I was reading your first post, I was thinking there was a restriction in the line. When you said that you took it apart and found water in the lines, I'd bet they were full of ice when you first drove it. Today was warmer than it has been the past few days, so the ice melted again.

 

[SHOMurph]

I can tell you before I cracked my exhaust before the turbo the car can be scary to drive. it really makes you prey for AWD.

Torque steer is not your friend.

must respect da' pow-wa.

 

[somedude_001]

I don't think it is as much torque steer as it is lack of traction. It only pulls when one tire looses traction and the other holds its ground. I can go WOT with my hands off the wheel and the car will go dead straight as long as I don't start spinning one of my tires... god I wish i had a LSD

 

[SHOMurph]

I don't think it is as much torque steer as it is lack of traction. It only pulls when one tire looses traction and the other holds its ground. I can go WOT with my hands off the wheel and the car will go dead straight as long as I don't start spinning one of my tires... god I wish i had a LSD

get some drag radials at 20-25psi. You'll feel it then but get alot better traction than with any z tire.

You'll have to be careful and learn how to drive it otherwise the torque steer will take you into the ditch.

 

[1slickRED89]

you hit the nail on the head. the BOV was not opening properly. I lubed it up and dissasembled my wastegate today (which for some reason is missing a bolt) and all of my vaccume lines were ful of water? I also moved the wastegate signal to the turbo housing and now it only makes 5psi of boost

the water is probably from condensed exhaust gas. connected to the manifold, the wastegate diaphram will be in vacuum most of the time, sucking in exhaust gas around the plunger stem. exhaust gas is mostly water vapor. I would suggest refrencing the WG at the compressor and just getting a diffrent wastgate spring to get the boost back. universal WG springs are $20 on ebay.

 

[somedude_001]

i did reference at the compressor and lost 3psi but i'll be getting a manual controller to compliment my new toy

i will make a thread about that later though

 

[HotRodKid]

..... to compliment my new toy

i will make a thread about that later though

your new toy is hot ....

now get me the parts i need so i can make your new toy fit

 

[somedude_001]

we need to hit the junkyard for parts :snky:

 

[jayparot]

help me build a turbo on my car please ......

 

[somedude_001]

contact hotrodkid