I wonder what style of sensor it is. I would consider it if it would spit out a 0 - 5v signal... and if I had money

 

Ref the nut holding the comp wheel coming off- Arent these cars running left hand threaded shafts? Thought that was a given on performance turbos, and would solve the nut loosening issue?

 

From what I can tell, it's optical, might need to put a dab of paint on one of the turbine blades.

http://www.dwperformance.com/kommerc...GAR781328-0002

http://www.turbobygarrett.com/turbob...d_sensor.html#

They offer a kit without a sensor for datalogging only, so I'd guess datalogging is also an option with the sensor. If they put out 0-1v for some reason (I don't see why they would), you could always build a stepper circuit to get it up to 0-5v.

 

I have a turbo tach on my car.


PEOPLE ARE JUST SO THICK AND NARROW MINDED.

BOV is a waste of money. DONT WASTE YOUR MONEY.

If your front nut on your turbo came loose, it was built by an idiot. Seen it happen many times.

 

What's your current turbo spooling to? And how does shifting gears affect the rpms of the compressor w/o a BOV? Please give solid numbers, preferably a specific log showing the values or a graph showing compressor RPM's from WOT/full boost to 0 Throttle back to WOT/Full Boost.

 

Are you logging it at all or is it just a gauge of some sort? Do you have any information you can share about blowoff vs no blowoff?

 

Consider me ruffled.

 

The holset speed sensors are magnetic.

 

I'm glad someone else is doing this and not me.lol.It always fun to what if...lol.U should start a fund for a replacement turbo.I'd donate.lol

 

proof or fail

 

turbo hasn't exploded yet. i've been driving it all weekend

 

i want to resurrect this thread. i have facts, so its not hearsay :-D

1) i bought a used single turbo gt35r ~9k miles on it. (previous owner had BOV)
2) got turbo and no play in shaft any direction
3) installed and idled - no shaft play
4) put 4 hours into street tuning - no shaft play
5) drove to DGRR and around the hilly streets up to 10 psi (1300 miles total trip)

i did steps 2-5 without a BOV. lol partly lazy, and part courage from this very thread.

Im working on installing my WI and get my elbow welded for my BOV and i noticed: i have ridiculous shaft play. if i spin it by hand, i can hear the bearings make a lub dub sound.

Deals Gap obviously caused A LOT of compressor surge. the most i think a car can be subjected to.

I dont know if shaft play and bearing sounds equals bad things. all i know is that the turbo is not the same lol. something's different. not performance wise, just spun by hand.

Of course, these facts dont say jack squat, but its interesting at least. the turbo could have bad bearings, 1300 miles on it could be bad either way. idk. just sharing my findings

 

I have been driving my lotus almost daily lately,

since january I added 3k more so total 35k hard miles on stock
10yrs old t25's, no bov and they still have lightning responce

 

So here's the first and most important question: are you sure there's something wrong with your turbo?

I can't say I've ever run a ball bearing turbo without a blowoff valve. They could be more sensitive to this and maybe the lack of a blowoff caused a problem. Or you could have an oiling issue, or you could have just gotten a bad one, or there's nothing wrong at all. Now let me ask you this: is there axial shaft play? Can you push and pull the shaft in and out? You would think running no blowoff valve would cause that kind of play if any. And axial shaft play is the worst kind.

Also, a lot of the larger (and ball bearing) turbos do seem to have a little bit of radial shaft play (as you have been now noticing) even when new or almost new. Is the shaft play so bad that your compressor wheel contacts the outside of the housing? It seems strange to me that you had zero shaft play when brand new, when a lot of people have a little bit of play out of the box. Maybe you should keep driving it and see what's up. It's kind of hard for anyone else to offer definite opinions without seeing the turbo firsthand. I wish I could have made it to DGRR this year. I went in 2006 and since I am in NC it's just an afternoon trip. With the economy though the budget just won't allow it.

btw, still no problems with my turbo.

 

If anything the BB units should take the punishment more then the journal bearings.

thewird

 

That is the question. :-) i dont have any problems. the only reason i played with it was i took the air filter off to mount the water injection.

shaft play is NOT far enough to touch housing
shaft play is a little axial as well.
I didnt text axial shaft play before hand

the oil feed is an excellent question, i can verify that my oil feed was operational since the first moment because i didnt have my return line completely tight and it leaked oil onto the mani.

the only concern i have is the sound of the bearings. they sound like bearings that are worn down a little. like one ball is sub par. i think you know roughly what i mean.

ill gladly run the beast for a while more. im installing WI, so thats only one more thing to complicate the situation lol

 

i don't know, my turbo makes a little bit of a sound when I spin it by hand. I wouldn't write it off as a damaged/blown turbo when it doesn't have any symptoms. There is usually an acceptable tolerance for shaft play on a turbo, although I can't say what that would be on your specific unit. Check out this shaft play inspection procedure on a Porsche 944 turbo (which are externally wastegated from the factory, interestingly enough):

 

It's a cryin' shame there aren't more "8 months and counting with a blow off valve" threads. Wonder why that is...

 

I would also like to try this setup with my new single turbo swap. It saves weight and simplifies. Also, the single kit I got came with a Turbo XS RFL (Really ******* Loud) bov which I have no interest in running.

My question is, are there any additional concerns running bov-less on a road course or under race conditions?

 

hm... not really.

if you wanna be an individual, put the TB before the compressor.

 

Some people argue that running without a blowoff valve will result in less response as you change gears. Based on firsthand experience I don't think it matters either way.

 

Some people also argue that running without one increases response between shifts since you don't have to re-pressurize the intercooler pipes etc.

Anyways, because of this thread I decided to not upgrade my little Greddy BOV so I'll keep having my butterfly noise from my turbo

thewird

 

http://www.youtube.com/watch?v=9DR5pPwGOkk

1st gear (1/2 throttle) and 2nd gear (WOT) pull without a BOV. 16.5psi

 

1st gear (1/2 throttle) and 2nd gear (WOT) pull without a BOV. 16.5psi[/QUOTE]

how much power does your car put down? do you have big *** wide wheels and very good tires?

 

I haven't dyno'd the car on this engine and turbo, I don't have wide wheels, I don't have good tires, and I don't have money for any of that right now due to the economy.