Right, thought I'd start this. As some of you may know my cars a bit broken at present and I have a pile of parts ready to fit that gets bigger without it making its way to the car.

 

So lets start with what's up with the engine. Myself and gaz pulled the engine about two winters ago now, as one of the turbo's had failed. Compression was tested at this time with a very even 170psi across the board. Pulling it all apart we found a multitude of issues, egr hanging off causing an exhaust leak old sockets rolling about etc etc. We took that time to replace every damn crusty water and vac pipe and delete just about anything I considered a waste of space.

Water plenum bypass,

EGR,

AIV,

PRV,

Cruise control,

Aircon,

Think that's all. The turbos were rebuild by myself and for the first 50-100 miles things were bob on and I didn't give it too much stick. The first couple of pulls it detonated, new plugs, reduced the issue but it still did it a bit. Changed to a smaller gap and great the det was gone. The car was pulling very well at this point with virtually no lag and was dyno'd at 289hp bone stock, no extra boost no chip. Not bad for an old auto engine. Sadly it had started to smoke on over run, I assumed id cocked up one of the turbos during the rebuild. So I had been putting it off for months, well actually years now to pay out for brand new turbos. Anyways as the tax ran out I thought id do some more inspecting as the symptoms just didn't fit the pattern of failed turbos. The first thing I found was that lovely even compression was no more, cyl had a rather lame 115psi. Cue further inspection to work out exactly what block I had, manual/auto etc I assumed it was auto. That's when I found this...

That head casting reads R-10Y, wtf is that I thought. It's supposed to read 40P this was one of those penny drop moments. The piston crown sealed that moment of realisation and many dots connected.

That's right its an NA, 30p pistons are NA and 30p1 are TT defiantly no 1 on that code. Turns out r-10y is the later spec NA head aswell, so yeas 100% an NA block. Now this engine was fitted by a garage 4 years ago a few months into my ownership and we wont go into that too much but it wasn't a great experience and it transpires it was worse than I first thought. Anyway whilst they refused to reimburse me for that error, a good will gesture was sent out to me in the post of a few quid.

So a replacement engine is going to be sourced and fitted this winter. More of that and what's happening to the current late spec NA block.

 

So now more about that shelf of parts. I purchased last winter a full rear subframe assembly off Jaffa, the one off his time attack car. Loads of goodies already polybushed to death etc. So I stripped it down to bare metal and started painting it all with a few coats of lovely hammerite. This is how it stands at present;

So this winters aims are.

Remove front and rear bumpers, re underseal all of that and rip out and guff.

Delete HICAS system

Reloacte PS reservoir and fusebox

Switch over all suspension to new units from the shelf

Fit 354mm diameter brembos

Change engine out and preform various mods

It sounds like a lot, but hey winter is along time. Don't expect it to be coming through thick and fast. Im lazy haha

15 hours ago, nickz32 said:

Somethings deffo not adding up here, there no mechanical reason why it shouldn’t be revving up to the factory 7200rpm rev limiter. It has to be electronic systems based issue. But for the sake of being thorough, I’d do a compression and leak down test to eliminate any potential issues in the combustion chamber (I’m not suspecting any, but better to be safe than sorry and know for sure!)

the fact the dyno sheets don’t show what happens after 6200 rpm doesn’t really help with being able diagnose the issue.

Did the tuner give a reason as to why he didn’t Rev it all the way out to the limiter?

I don’t think the issue is VTC as I originally thought. The engine would still Rev out but it’s peak power would be made at around 5000 rpm and the torque curve would drop off more dramatically than that.

spark gap shouldn’t have made the slightest bit of difference at 16psi of boost, even at 24psi I ran NGK supplied gaps with no issue at all. Which makes me think ignition system based issue producing a weak spark

Is it still on a S1 PTU? Any sign of any misfire no matter how minor?

 

He said there was no point as it was plateaued, that if the power had dropped off there must be an issue as it should pull through the redline. He wasn’t comfortable pushing it past this apparently. Compared to other maps it seems I’ve looked at it seems that that plateau is pretty typical of stock turbo cars. 
 

It is on a series 1 PTU but it’s never caused a problem, especially not the stereotypical issue of hot misfire the issue I had was the opposite. It would misfire unless the engine was hot hot. 

I think a lot of the above highlights the issue. The ability to data collect with the stock ECU is really limited. 

1 hour ago, Stephen said:

I think a lot of the above highlights the issue. The ability to data collect with the stock ECU is really limited. 

That’s exactly why I went to Haltech so long ago! 
 

When my car was virtually stock (Stillen filter and kakimoto cat back) it made peak power at 6850 before tailing off to Rev limit….. and it stock boost made 339bhp at SRR. I’ll see if I can find the dyno print

 

Something I hadn’t noticed before is the fact you low boost makes peak power and revs out cleanly to red line yet your high boost doesn’t is also unusual! I’ll go back through your thread and see if there’s anything I spot that could be a cause, because at lower boost your engine is flowing enough air to breath all the way to red line, yet when you up the boost it appears to choke out

1 hour ago, nickz32 said:

That’s exactly why I went to Haltech so long ago! 
 

When my car was virtually stock (Stillen filter and kakimoto cat back) it made peak power at 6850 before tailing off to Rev limit….. and it stock boost made 339bhp at SRR. I’ll see if I can find the dyno print

 

Something I hadn’t noticed before is the fact you low boost makes peak power and revs out cleanly to red line yet your high boost doesn’t is also unusual! I’ll go back through your thread and see if there’s anything I spot that could be a cause, because at lower boost your engine is flowing enough air to breath all the way to red line, yet when you up the boost it appears to choke out

That choking out observation was one the dyno operator mentioned too, but that it’s cause could be numerous. 

I’ve gone back to 2017 and can’t see a spec sheet of your build bud, mind writing one out?

Engine and Drive train
120k service with belts, cam seals etc performed in 2015. Iirc. Replaced all coolant and oil flexible pipes.
Stock Turbos rebuilt and Balanced by CR Turbos with 360 thrust bearings and step gap seals. 
Stock size Fuel injectors. Chipped and socketed ECU to suit 16psi. Manual boost controller. 
SFS Silicone boost hoses. 
Full delete list, EGR, AIV, Aircon. Underdrive lightweight pulley. 
Aftermarket uprated radiator and oil cooler. 
Cone filter intake. Bailey DV26 dump valves. Godspeed intercoolers, ducts modified to suit.
Japspeed exhaust full system, divorced turbo elbows, decat and 2.25” system. 
Competition Clutch Stage 2 550lb rated, braided clutch with new master. Fluids all changed during conversion in gear box and diff. New seals and gaskets on diff and g box. New shifter bushes. 

Suspension and brakes
Power tricks front and rear camber arms Torsion rods.
Driftworks toe arms rear. 
Energy suspension full poly bush kit.
Driftworks HICAS delete kit.
Solid subframe and diff mounts.
Solid steering rack joint with energy bushes. 
Stillen front and rear anti roll bars. 
Cusco Front coilovers from an R33 and Tien rear from an R32. Solid top mounts with 6k front and 4K rear springs. 
Evo 8 Brembos callipers front and rear with 335mm front and 345mm rear vented and drilled discs. Braided lines, brake master brace, new OEM Master

Interior
Series 2 suede door cards with the electric passenger and driver. Series 2 Leather seats passenger and driver. 
No radio. Boost, oil temp and voltmeter gauges. 
 

Body 

Stripped back and coated in galvanised primer, the majority of the underside. Hammerite and Gravitex stone chip applied. Extensive cavity wax protection. Foam spoiler replaced with OEM copy in fibreglass. Orange indicators switched for white with orange bulbs, crystal rear lights. 9x18 AVS Model 5 fenders rolled F&R. Roof bars wrapped black. 

 

 

That’s a from a draft of the spec for the sales advert. 

I mean there’s nothing screaming out as a glaring issue.

2.25” exhaust is small and will be causing back pressure issues. That will be a contributing factor…. Be worth checking that none of your silencers/resonators have collapsed internally.

what brand air filter is it?

On 12/07/2024 at 16:07, Stephen said:

As it happens I was passing Horsham Developments so I popped in and had a long chat with Jez about the options they would recommend. I haven’t had anything back from SpecialityZ yet. I may just go Nistune and then the ability is there for future wether that’s me or someone else and the tube will be far better than any generic chip. 

I went the Nistune way and then had my Zed live mapped by Dyna Tune in East Kilbride.

At the first session, he noticed that the car was running out of puff at high revs, he duly connected a fuel pressure gauge and that showed that the in tank fuel pump was unable to provide enough pressure at the top end.

Once I'd fitted a new fuel pump (and new O2 sensors), the car was mapped to a very safe 335 bhp. Yes, I could have had higher power but I'm looking for safe and reliable - not just a high power figure.

So Nistune......a good, speedy service from Horsham Developments and well known to the tuners out there - recommended.

6 hours ago, nickz32 said:

I mean there’s nothing screaming out as a glaring issue.

2.25” exhaust is small and will be causing back pressure issues. That will be a contributing factor…. Be worth checking that none of your silencers/resonators have collapsed internally.

what brand air filter is it?

It’s actually 2.5” according to the blurb, maybe it 2.25” ID. In terms of the exhaust the biggest bottle neck would be the turbo elbows. 

On 12/07/2024 at 16:41, AndrewG said:

What are you running now?

Still running an SZ EPROM, albeit changed for the 740cc injectors etc. Boost pegged to make 480hp currently, as engine is not built. Would like to go Nistune purely for a custom tune, it needs leaning out. Link would be ideal but too expensive for me at the moment. But I have also considered by the time I have got a Nistune + Selin/equivalent + extra MAF, I am butting up against the cost of a Link anyway. 

1 hour ago, Peage said:

Still running an SZ EPROM, albeit changed for the 740cc injectors etc. Boost pegged to make 480hp currently, as engine is not built. Would like to go Nistune purely for a custom tune, it needs leaning out. Link would be ideal but too expensive for me at the moment. But I have also considered by the time I have got a Nistune + Selin/equivalent + extra MAF, I am butting up against the cost of a Link anyway. 

You can run a proper twin intake like with the Selin via Nistune, you need a dummy maf and it’s not quite as accurate but… choices…

Honestly, for you spec, I wouldn’t bother with the selin. Any gains would be marginable. I ran single intake up to 590hp with no problems.

 

Just for clarity, when you raised the boost, did you got from wastegate pressure straight to 16psi, or was it raised incrementally?

12 minutes ago, nickz32 said:

Just for clarity, when you raised the boost, did you got from wastegate pressure straight to 16psi, or was it raised incrementally?

Wastegate to 16. 

13 minutes ago, nickz32 said:

Just for clarity, when you raised the boost, did you got from wastegate pressure straight to 16psi, or was it raised incrementally?

Wastegate to 16.

 

I got a reply from Sebastian at SZ. Basically he encouraged me to go dual maf with a translator and said their version will be ready very soon. Then said that our 99ron is probably equivalent to their 93RON. And that because of the stock ECU it prone to running rich, double check for boost leaks. The dyno print out wasn’t one he is used to seeing so can’t say much. I wouldn’t go as far as to say it was a disappointing reply but it didn’t really help. 
 

14 hours ago, Stephen said:

I wouldn’t go as far as to say it was a disappointing reply but it didn’t really help.

To be fair to SZ I would have thought it rather challenging to diagnose when they are over 5K miles away.

What are your plans for the car Stephen? You still intending to sell it and just need to get it running well enough to do so?

 

1 hour ago, AndrewG said:

To be fair to SZ I would have thought it rather challenging to diagnose when they are over 5K miles away.

What are your plans for the car Stephen? You still intending to sell it and just need to get it running well enough to do so?

 

Agreed and I don’t wish to be negative in that context, just wanted more information about the options. 
 

If someone came along tomorrow and said il buy it for what I’m after I’d sell. What I do seem to be seeing though is a lot of cars, not just Z32s are not selling particularly quickly. That said I’m also not 100% on what else I’d want. I flip flop between a C6 corvette and a 370z but honestly both have compromises, the LHD thing is a real put off for me and the 370z feels very similar but also slow and making power from it is not cheap.
 

I did start looking into a Maserati Grandturismo but that’s a money pit, bad parts availability, still deprecating etc. The Cayman also appeals but I don’t like the sound or the Boxster association. 

Just to add to that, the car actually runs pretty nicely now. It’s just a case of I know it can do better. It’s kind of like an unticked box. 

On 16/07/2024 at 21:35, Stephen said:

Wastegate to 16.

 

I got a reply from Sebastian at SZ. Basically he encouraged me to go dual maf with a translator and said their version will be ready very soon. Then said that our 99ron is probably equivalent to their 93RON. And that because of the stock ECU it prone to running rich, double check for boost leaks. The dyno print out wasn’t one he is used to seeing so can’t say much. I wouldn’t go as far as to say it was a disappointing reply but it didn’t really help. 
 

Yes, our 99 is the same as their 93.

 

personally, the amount the dual MAF setup costs, you’re 80% there to a Haltech Platinum Pro standalone that absolutely snots a stock ecu and “dual” MAF setup in every measurable way possible…. I know what I’d do out of those two options!

 

This is where I feel whoever did the dyno last time could have spent an extra few minutes to help diagnose. Really, they should have dropped the boost to see if the issue persisted or changed or disappeared. Maybe that was a lack of knowledge of the car on the tuner part and has taken the “engine wants what it wants” a bit too literally. I wouldn’t be using him again.

Again, if it were me, I’d have tried incremental increases from wastegate to 16 psi to establish where the loss of ability to reach full RPM disappeared (Stock 9psi, 12psi, 14psi). That would have shown if it was an airflow problem or something else. I’d suggest it would probably be worth an hours dyno time at Horsham etc just to do some runs on different boost levels, monitor the AFR’s and see what the engine does and where the problem arises. I wouldn’t do it on your own with just boost level changes as you don’t know what the fuelling has been set up like above where the tuner was terminating the dyno runs

Dont give up on the car yet. A bit like my situation, it’s not the cars fault that it’s not running right….. after all it’s an inanimate object! It just needs setting up properly! On a proper tune at 16psi, it should be in the low 400’s and a very very different car to drive.

Looking to sell next month.

The spec is as follows;

Engine

60k service with belts, cam seals etc performed in 2015. Iirc.

Turbos rebuilt and Balanced by CR Turbos with 360 thrust bearings and step gap seals.

Full delete list, EGR, AIV, Aircon. Underdrive lightweight pulley.

Aftermarket uprated radiator and oil cooler.

Cone filter intake. Bailey DV26 dump valves. Godspeed intercoolers.

Japspeed exhaust, divorced turbo elbows, decat and 2.25” system.

Suspension and brakes

Power tricks front and rear camber arms and Torsion rods.

Driftworks toe arms rear.

Energy suspension full poly bush kit.

Driftworks HICAS delete kit.

Solid subframe and diff mounts.

Solid steering rack joint with energy bushes.

Stillen front and rear anti roll bars.

Cusco Front coilovers from an R33 and Tien rear from an R32. Solid top mounts with 6k front and 4K rear springs.

Evo 8 brembos front and rear with 345mm vented and drilled discs.

Interior.

Series 2 suede door cards with the electric passenger and driver. Leather.

No radio. Boost, oil temp and voltmeter gauges.

I think that’s pretty much everything. I never intended to sell it so I’ve never actually written it all down before.

I’m looking for 15k does that seem reasonable?