SP Turbo Removal (or replacing the turbo mounting studs)

[CT]

Hi Garry, let me guess, it's one of the rear ones......The solution is twofold; 1) get nissan studs, locknuts and lock down tabs from an S15 - must use OEM Nissan. The stuff from GCG is garbage - don't ask me how I know. 2) Get a flexible joint put into your exhaust just below the dump pipe. The exhaust puts pressure on the turbo via harmonic vibrations and the studs are the only thing supporting the turbo. Eventually, they will fail. At some stage, I will look into another bracket to support the turbo too. Yet another poor design on the SP.

[Blue94t]

Even with Inconel studs on my AVO kitted 1.8 I had trouble keeping the turbo done up tight. I also had a flex joint in the mid pipe where it joined the dump pipe.
The Nissan gear sounds like a top solution, fortuneately my new motor comes equipped with all Nissan OE fasteners

Jake

[bigdog]

As Garry knows mine have been replaced with inconel studs and are all lock wired and have never been a problem since... my problem is the manifold to head studs that weren't replaced at the time so I now have one nut that is stripped from repeated re-tightening, and these are the worst ones to get at to replace. I'm hoping it will last till I need to do the clutch or something more major to justify pulling the motor out.

[SPy vs. SPy]

Garry,

There's a few other things you should check whilst it's in bits, per below.

http://mx5cartalk.com/phpBB-3.0.2/viewtopic.php?f=29&t=27386&start=0&st=0&sk=t&sd=a&hilit=exhaust

not had any problems since I had this done.

further to that problem, I finally chased the last of the fuel consumption issues to a stuffed by pass valve, currently on valve #5 in 6 years. The valve was fluttering at moderate throttle allowing already measured air back to the other side of the AFM where it would promptly get itself measured again end result, computer says air + X air needs fuel + X fuel, regardless of motor getting air + fuel + X fuel.

[Garry]

CT, where were you 2 days ago............ I put everything back together last night.

[bruce]

Touch alloy it will be A-O-K.

[bigdog]

Garry, There's a few other things you should check whilst it's in bits, per below.

Did you pull the manifold off SPy, or did you take the less painful route of paying someone else? I am contemplating doing mine and just wondering if i really want the world of pain that might cause.... what are your thoughts?

Which valve were you referring to - the PCV or the BOV?

[SPy vs. SPy]

Garry, There's a few other things you should check whilst it's in bits, per below.

Did you pull the manifold off SPy, or did you take the less painful route of paying someone else? I am contemplating doing mine and just wondering if i really want the world of pain that might cause.... what are your thoughts?

Which valve were you referring to - the PCV or the BOV?

It was done by a known local turbo guru via a recommendation by ChipTorque. All the parts (nuts, studs etc) came from the local nut & bolt shop, made by a US company with a germanic name Wuxxxxxxxx with dots over the u (umlaut) IIRC.

The biggest problem, as shown in photos, are most of the studs are too short.

You could very easily do it yourself, but make sure Mrs Bigdog isn't in easy listening distance at the time, a fair few loud woofs may be enunciated in The Kennel aka Bigdog's garage.

Per CT's sage advice, get the Nissan gaskets etc, just tell everyone you bought OEM Mazda ones

I'd also recommend getting the manifold machined whilst it's out.

The valve I'm referring to is the BOV. Even the fancy rebuildable Billet Alloy one I bought (for a kings ransom) failed, they just can't handle all the difficult highway miles

[bruce]

'Wurth, Wurth' to Big Dog.

[Garry]

Spy,

I went through 2 Mazda Bosch BOV's then switched to a Porsche version of the Bosch BOV then tried a GFB alloy BOV and went back to the Porsche one because it worked the best. It looks identical to the Mazda one externally but the seal plate inside is metal, not plastic like the OEM one. The spring has a little more force on it as well. It seems to be much more durable than the originals seeing as I've had it for several years now and it's still working fine.

The GFB BOV made the boost seem a bit more crisp but the stumble on throttle lift off was woeful, whereas with the Porsche BOV the stumble is a lot softer, even allowing a little tiny bit of throttle movement sometimes before the stumble. With the GFB BOV I only had to think about lifting off the throttle and the stumble would just about throw me through the windscreen.

I had a chat to the guys at GFB about their BOV and what it was doing to my car and they were very helpful and offered to do some tests and play around with springs to improve its compatability with the SP but I never got around to heading out to see them.

[PASHN8]

I take it this can happen easily to the SE as well?

I have a sound that sounds like an exhaust leak coming from somewhere near the turbo under the heatshield. Symptoms are lazy boostings, seems to have more lag whilst spooling up in 1st/2nd then picks up all of a sudden and exhaust splutters and pops/crackles on overrun when slowing down in gear.

CT, being an SE, can I still use the S15 studs/fasteners/nuts etc if I have to change bolts?

D.

[Hammer]

....then switched to a Porsche version of the Bosch BOV...

Garry,

Where did you get your Porsche Bosch BOV? From a Porsche Service Dealer? Or do you know the part number and ordered it through a Bosch seller? How much are they approximately?

I'll be keen to test one out providing they are not too expensive.

Cheers

[Hammer]

...1) get nissan studs, locknuts and lock down tabs from an S15 - must use OEM Nissan.
2) Get a flexible joint put into your exhaust just below the dump pipe. The exhaust puts pressure on the turbo via harmonic vibrations and the studs are the only thing supporting the turbo...

CT,

Great advise, I too just had to replace my turbo bolts 3 months ago. Told my local Mazda Dealer not to use the OEM for the SP. So he got some studs from a reputable Turbo specialist. So far so good. But don't have absolute faith that they won't come loose again.

So if they do, I'll try your suggestions. I'm guessing you can simply get the S15 bolts & nuts from any Nissan Spareparts department? Do you have any clue of the cost a set of 4 would cost?

And for the flexible joint you suggested? What did you use?

Thanks again.

[SPy vs. SPy]

Spy,

I went through 2 Mazda Bosch BOV's then switched to a Porsche version of the Bosch BOV then tried a GFB alloy BOV and went back to the Porsche one because it worked the best. It looks identical to the Mazda one externally but the seal plate inside is metal, not plastic like the OEM one.

another forum SP owner put me on to these http://www.goapr.com.au/products/apr_r1-diverter-valve.html they work very well, off throttle is very nice and smooth, hold boost very well too.
I'd definitely recommend one, price is a bit ouchy though, then again a Bosch valve is $50+ and is a throwaway part, times that by 4 . . .

[Garry]

Hammer,

I got the Porsche BOV from a dealer. The original one was around $50 but they have since gone up to over $100. I have the Porsche part number at home. I'll look it up for you.

Spy,

The VW/Audi guys replace their Bosch BOV's with the APR ones and seem to like them a lot.