FYI,

If you have a Tial blow off valve on your rx-7 and are receiving compressor surge, send them an email. They will send you the correct .7 bar RX-7 spring for free. I installed mine last night and it fixed the problem.

I believe someone posted about the spring a while back. I just thought I would give you guys a heads up and let everyone know they are available.

tialinc@earthlink.net


Bryan

 

how hard is it to replace the spring? Tial once told me that it was too difficult for most to do and so I would have to send the whole BOV in.

 

Thanks for the info. The person you were referring to was probably me. My original spring combo was a big blue with a small yellow. I change it to a big green but it gave me between 13 and 15 LBS. of boost instead of 11 so I just bought a small blue which should give me around 10 with my setup. ( Pic below ) I will cross my fingers. I will then use a manual high temp air valve to adjust boost pressure. This will be in line with a solenoid. I will run 10LBS in first and second off of wastegate spring pressure so I can get traction and 16 - 17LBS from 3rd up. All I have to do is flip a manual switch. I would like to run an electronic boost control but I am currently POOR. Valve and solenoid = around $40.00. Also a better set up than that brass thing advertized on Boost.com. I also need to upgrade my ignition. I have to do more research though.

It took 2 people to replace the big green spring. I could have done it with c-clamps when the wastegate is installed on the car.

 

are you talking about the wastegate spring, or the BOV spring???

 

RX-007 is referring to the BOV spring, but 80 cu inch is talking about the wastegate spring which has nothing to do with surge..
The tial bov spring has an cracking vacuum of about 19", for the 7, I found that a cracking vaccuum of about 14" is just about right, I get a little surge but not near as much, I think I actually may need another Bov...max

 

Thanks, that's what I thought. So, is the spring hard to replace in the BOV? I agree, the tial may not be the best BOV for our application. Especially considering the cost.

 

This is all news to me.. I thought the everyone loved the Tial? I just got my blue Tial bov two days ago, I haven't installed it yet as I am still installing the turbo kit.. The Tial should be fine for a TO4E application no? The valve on it looks pretty good sized, I will email and get the softer spring though.

Matt

 

The spring is not hard to replace, with the banjo bolt in place on the top, I put in my vice with some cardboard to protect the finish, then undid the head bolts, loosened off the vice and let it seperate, you can also hook up a vaccum gun, take the bolts out, then slowly relieve the vacuum, the spring just falls out once its apart, assembly is the reverse of course..
MJW, the construction is top knotch, the bov makes other valves look like Fisher price made them, and it works pretty good with a light spring, I just get a little surge I think mostly because I like to feather the throttle rather than pull right off the gas pedal..Max

 

The spring is pretty easy to change. Just unclamp the valve and take the top off by backing out all the allen heads bolts. The spring tension isn't too bad, so putting it back together in the referse order was easy. I am not getting any compressor surge, but I'm only on 10psi with my t78.

I'm actually trying to get my greddy wastegate working with my profec b today.

Speaking of which, there are three ports on the waste gate. One on the lower side, one near the top and on the side, and one on the top. What's the one of the side of the top for?

 

AHHHHHH Ya see drinking and a typing after a hard days work isn't a good thing especially when skim reading. Oh well never mind.

 

I don't know if anyone is still reading this... but I just got me new spring from TiAl and it still surges... I let off fast and still get the three stooges (wub, wub, wub, wub pshhhhhhh)

There is no way this is supposed to happen. This is on my factory (2nd gen) turbo but my old turboxs didn't surge. On top of that, the valve flutters at idle with my port? WTF? I dont' know what to do.

 

Umm, are you sure its the wastegate making the noise? If you have an air flow meter, it could be the flap.

 

New spring solved my problems. No more wub wub.

 

Sorry, I'm takling about the BOV, not the wastegate.

Weaklink, do you have a ported motor? Does the valve open at idle? Miny flutters with the engine RPM as it fluctuates. I guess it isn't a huge problem since I have a Haltech but I'm sure it isn't supposed to do that... Where are you pulling the vac line from?

TIA

 

I have noticed that mine is open at idle. I thought it was weird. Doesn't seem to fluctuate much though. I don't have my car with me right now, or I'd track it down. Yes I have a mild street port and single turbo. Functions great. I'm happy with it now.

 

Hmm. I'll give it a while to see how it does. Just don't want to ruin the new turbo that I'll be putting on soon. Doesn't sound like that will be an issue.

 

But correct me if I am wrong , doesn't the engines vacuum drop (go towards atmos.) with a larger port ? , so this would have less of a "pulling" effect on the BOV 's diaphragm and allow it to stay closed at idle , so why would yours be open at idle ? , When my engine was stock the vacuum was about 16"H2O , now with the bridge it is about 5" H2O.

 

i have the same question so let me know when you figure it out.--j

 

My vacuum was about 19 before and is about 15-16 with the port. You must have a huge port to only pull 5.

 

I'll have to double check my Vac reading tomorrow. I do agree that the port should pull less vac, but as long as there is an equal force on each side of the valve it should remain closed. Whether both sides see light or strong vacum, or boost, it should remain closed with the spring.

BUT I think the reason that it fultters is actually since the idle has a bump to it. IE my idle fluctuates ~100 RPM with the port (Not nearly as much as a bridge port) Therefore the vac reading is constantly changing which could cause the pressure on the different sides of the TB to oscillate with RPM. As the RPM drops, the vac increases (away from atmosphere) on the engine side, leaving the higher pressure (or really just less vacume) on the IC piping side, thereby allowing the valve to open. Does all this make sense?

This would imply that a stronger spring is needed to keep the valve closed during idle. Yet the fact that I still have surge says the spring is too heavy.

For What it's worth, my BOV is near the turbo. I read a million and one posts about this and found nearly a 50/50 split between there and after the IC near the TB when I did it origionally. Although I read a pretty compelling argument yesterday for placing it near the TB when considering the pressure drop across the IC. I'll have to dig that post back up.

That's enough for now. Let me know what you think.

 

bump
does anybody have the Tial contact info
i just got a BOV from some BS ebay seller took 4 weeks to ship the BOV to me, and not having the right spring...
plz give me tial's contact someone ....
that earthlink is not working

 

try any of these:

tech@tialsport.com
greggjones@tialsport.com
char@tialsport.com

i actually got the 14lb spring. char was the most helpful for me. they just referred me to a local tial dealer in the end, but you can ship it to them and they'll switch it for ya.

 

I was able to send them my spring in exchange for another. In the mean time a went to a local hardware store and bought a spring that felt softer. It was a little smaller in diameter but It work perfect. I guess I was lucky. It held fine to 17.2 psi (as far as I have gone so far). But I do have the spring from them in now (7psi).. Every car will be a little differant (supra, rx7, etc..) It depends on how much Vac you pull at idle. The valve requires both to work correctly. My car only pulls (12-14) old motor I am sure the compression is getting low.

 

so are you saying the tial is **** for the fd? which is the best for the fd? i was thinking about getting a tial but now i dont know......

 

also how do you know if your getting compressor surges?