HX-35 Compressor surge during boost

[nad1]

Okay, I'm going to write a short book here about my current issue, and my past success with the HX-35 setup. I posted this on 'Talk yesterday, and haven't had any response, so I figured I'd see if anyone here had any insight on the topic.

To start, I had an HX-35 that did not have the provision for an internal wastegate, and had no issues with compressor surge at all. However, I did blow the turbo up due to a oil drain issue. This was using the BEP .55 A/R exhaust housing.

So now I have an HX-35 that came WITH an internal wastegate, but I removed it and set it up for an external gate just like the previous HX-35. This was also using the same BEP .55 A/R exhaust housing.


Since I've had this turbo on, I've been having compressor surge issues, DURING boost, and after letting out. If I hold it at about half throttle, and push about 10-15 PSI for more than a couple seconds, I start getting surge, and it doesn't stop unless I let off, then I hear BOV flutter, which could be surge, or just my crappy GReddy Type S.

I've heard that installing cams would fix this issue, so I've installed 546/547 WebCams, and that did not solve the problem. I've checked for boost leaks numerous times, with no leaks. I do know I have a couple exhaust leaks, but they're very minor, not sure if that could cause it.

So basically, I've had 2 HX-35s, one had no issues, and this one has constant surge issues. NOTHING else had changed between the two, I literally swapped the turbo and changed nothing else.

So is there a difference in the internal gated HX-35 that would cause me to have surge?

And as far as ways to fix this problem, would I be better off just selecting another turbo? Or is there something else I can do to remedy this? If a turbo change is necessary, what Mitsu turbo would be recommended?

Sorry for the longwinded post, but I'm tired of trying to figure this out on my own, and just need some input from some of you guys. Thanks for the help.

 

[livedsm4g63]

You want my TD05-20G or my GT 3582R?

Are you sure your BOV didnt take a crap on you?

 

[nad1]

I originally thought it was the BOV, but it is not a BOV flutter than I'm hearing when it's surging. It sounds more like the wastegate blowing open and closed as I'm boosting. But it's a Tial 38mm MVS, so I don't see that being the issue.

Also, I've tried this with and without my Hallman Pro boost controller, same result either way. At WOT high boost (18-22psi), I have no problems, but when I start to let out of it slowly, right around 15-10 PSI it starts to surge.

 

[livedsm4g63]

What spring are you using in your wastegate? Maybe its to heavy?

 

[JusMX141]

HX35's have an anti-surge feature in the cover....if you're having issues with surge, something's majorly wrong.

 

[nad1]

I honestly don't remember, I got it from STM a few years ago and don't remember what spring I ordered. I wouldn't think that would matter, because I should still be able to adjust with the MBC? And I would think maybe the spring being too light would cause it to open and close constantly?

I would just buy a new wastegate and BOV, and see if that fixes the issue. But who has that kind of money to just throw at a problem hoping it fixes it?

HX35's have an anti-surge feature in the cover....if you're having issues with surge, something's majorly wrong.

See, I keep reading this, and that's why I was thinking that maybe the ones that came internally gated didn't have this feature? Because like I said, with the other HX35 I had, I didn't have a single problem until I cooked it. But ever since I bolted this one up it's been this way.

 

[duckie1098]

See, I keep reading this, and that's why I was thinking that maybe the ones that came internally gated didn't have this feature? Because like I said, with the other HX35 I had, I didn't have a single problem until I cooked it. But ever since I bolted this one up it's been this way.

I have a internally gated HX35 that I welded the flapper shut on, I've not had any issues with surge on mine.

 

[JusMX141]

See, I keep reading this, and that's why I was thinking that maybe the ones that came internally gated didn't have this feature?

Nope, they did.

 

[nad1]

Nope, they did.

Okay, now that I know that's not the case, do you have any other suggestions of what to check on my setup?

http://www.dsmtuners.com/forums/turbo-system-tech/370159-hx35-compressor-surge.html

This is almost an exact description of the issue I'm having, and it doesn't look like the OP ever followed up on what fixed the issue.

 

[nad1]

Just out of curiosity, would the fact that I had a 7 Blade HX-35 before, and now I have a 8 Blade make any difference? No surge with the first, but surge with the current one. Anyone have any insight on this?

 

[JusMX141]

Sure, the 8-blade makes more airflow at lower boost levels. It's what that particular wheel is designed to do.

I've still never personally witnessed a HX35 surging on any application. The older H1C's without the MWE groove liked to surge, but never a HX35.

 

[hayourwifeleftu]

I was about to ask if you are sure it's an hx35 and not an h1c.

 

[nad1]

It's for sure an HX-35. I'm not sure if it's an 8 blade or 7 blade, I'll have to pull my intake pipe and look. Maybe I'll try to sell it and buy a 7 blade to see if that solves my problems.

Also in the process of trying to switch back to a 1G BOV instead of using this stupid adjustable GReddy BOV, as it might be the issue as well...

 

[red_devil]

I would say it's your bov. Does it have both springs in it still? I was constantly having issues with something very similar to you, and installing my TiAl bov fixed it.

 

[nad1]

Yes, my GReddy still has both springs in it. I had one spring in it when I had my 16G because it surged when I let out of the throttle. But now with both springs I'm having surge during boost. Working on getting a 1G bov setup to see if that helps any.

 

[nad1]

I found an old 1G BOV laying around that was already drilled for a GReddy flange. Slapped it on the car (VTA temporarily), and believe it or not, I think that fixed my issue. I still get a very light flutter when adjusting the pedal to decrease speed, but nothing like it was.

Thanks for everyone's help, but I think we can mark this one resolved. Thanks again to everyone for their help.

 

[livedsm4g63]

PLUS 1 FOR ME!

Glad you were able to figure it out.

 

[JusMX141]

Good 'ol Greddy Surgemasters. Why people actually remove the best valve you can use on a 1G and buy those things is beyond me.

 

[nad1]

I've probably had 10 different BOV's on this car. Stock 2G originally, 1G BOV, type S, Synapse Synchronic, type RZ, type S again, 1G, SSQV, type S again, and now I'm back to a 1G. 1G BOVs still have the best sound, and work the best out of all the aftermarket junk I've bought. If I ever switch to Speed Density, I will buy a TiAL and never have to worry again, but until then, I'm gonna stick with a 1G BOV.

 

[Archer Fabrications]

^ I was gonna say... you didn't try a tial yet!? hah good choice. They have a tial with a recirc tube though fyi.

 

[red_devil]

Yeah that's what I just installed. It's almost silent anything under 15psi, so very sleeper. But at 25psi its louder than my type s. Just hope more people see this and not buy the pos Greddy.

 

[donniekak]

It's the bov. The part throttle part is the giveaway.

 

[nad1]

Yeah the only reason I didn't use a Tial was because I didn't want to have to buy a new UICP or try to find someone around here that can weld a flange on for me. I seen that they have a GReddy to Tial flange adapter, but that's gonna look bulky as hell, not sure if it would even clear my hood with as big as a Tial BOV is.

 

[Dert]

I bought the greddy to Tial flange when I got my tial Q, not a chance in hell of closing the hood. When I had my type rs the adjustment screw ground a hole into the underside of my hood as it was rubbing. The flange adds almost another inch to the height. I just went to a welding shop, had them cut the greddy flange off, TIG weld a patch over the hole and put the tial flange down lower on my IC pipe.

 

[nad1]

I've taken the GReddy BOV apart numerous times and can't see what was causing it to do this. The diaphragm looks fine. I was planning on selling this so I can make some of my money back, but I don't want to sell it if there's something internally wrong with it.