Mistakes were made, my R34 Story

[GTSBoy]

6 minutes ago, MBS206 said:

Change the pump... Or you'll likely regreg it in 12 months time if it's clunky...

I see what you did there.

[Kinkstaah]

12 months on the pump would be great!

The pump is really not that old, I have a receipt from when it was purchased new and it's done ~25,000km since then. it really should be okay. And if it it's not, well. I figured I'd at least run it out as it's already tapped for the nissan temp sensor sticking out of it.



Here it was, ready to make it's journey back into the bay, though the balancer had to be tightened/seated more.

And it was very stubborn to sit back. So much so that the crank bolt ended up stripping inside the crank instead of the balancer moving to it's intended location.

 

[GTSBoy]

Can you at least move to a location without so many ladders, black cats and mirrors precariously propped up ready to be knocked down?

Or buy yourself a 1 ton bulker bag of salt to drag around with you. Just, you know, sling it over your shoulder?

[MBS206]

Stroker kit time?

[Kinkstaah]

Some updates.

After a lot of praying and some inspecting of crank threads, we've found that they were both kinda munted but nothing seemed terminal.

The other option was drilling and helicoiling the crank. That is obviously the last option so we decided to at least try to get a OEM GM bolt in to GM Specs.

So after honing/linishing the balancer from it's .002" interference fit to a .0018" to .0015" to .0013" it eventually slotted on to the crank. ATI state the interference is nominally 0.0007-0.0009... so it's still snugger than ATI reckon and explains the issues we had to fit the thing to begin with.

New GM bolt went in at 37 ft/lb then torqued 140 degrees after which was EXTREMELY   but it tightened up to 140 degrees and it was a lot of force. So all things considered, the balancer is secured to the exact specs that GM want with the OEM Stretch bolt, (that ATI say you can use..) and the balancer itself is seated and snug AF.

So WOO.

Engine is now back in the car with lots of swearing.

Bellhousing bolts done up, driver side manifold is on, AC Compressor and hard lines are back on the car.

Next step will be to connect various engine bits/wiring/intake/radiator etc. Then oil and coolant and ... test start it?

And of course, looking into this issue... which actually doesn't look so bad - It looks like it can be twisted back into shape with a set of multigrips.

Anyone wanna buy my bonnet? Boy it looks good over there and sunk cost sucks.

[Kinkstaah]

So, more pain.

The FAST manifold is a little larger than the stocker. This is problematic because there really wasn't much clearance to begin with, so going from 'barely enough' well into 'no' is sad based on the external dimensions of the thing, even though where it bolts to the head is the same.

Result is the fuel rails sit a good 25mm higher, and this is a bit of an issue with the wiring that runs behind the motor, and the fuel lines, and everything else.

When pushing the manifold on, it required a huge amount of force to crush wiring looms to fit it, sensors like the MAP sensor are about 1mm from the firewall, and the FPR just has to bend ABS lines to be forced into place. After some brainstorming and some sad drinking, the loom for some reason ran from the grommet behind the ABS sensor, then to the driver side head, then back to the passenger side head.

So all of this was pulled back and stripped, a few wires cut and rejoined, so that the 'branch' was now on the passenger side's head as below:



Before you basically couldn't see anything behind the driver head. This is much improved!

The MAP sensor is now pointing up (instead of at the firewall)

Brackets have been made up for the rail. The rails are for a LS1, the manifold is designed around a LS2 as it's base. Which of course has slightly different bracketry and water pump clearance, hence the mods people need to do.

Should be hopefully mounted tonight. I spent money on a new FPR that is slightly more compact than my Turbosmart FPR1200.

The gauge has also been moved to the rail. There's also apparently an ORB to AN Union instead of the adapter, because the ~25mm of the current adapter is going to make the difference.

Provided this all goes together and arrives today, it'll be the totally not stressful attempt to start it.

[The Bogan]

Bonnet clearance?

[Kinkstaah]

7 minutes ago, The Bogan said:

Bonnet clearance?

The old manifold was quite under the GTR strut brace. 
The new manifold is quite [unknown] the GTR strut brace.
The GTR strut brace was needed to clear the bonnet vents.
The Old strut brace will almost certainly clear the new manifold, but not the bonnet vents.
The old strut brace will almost certainly clear the new manifold, and the new bonnet without vents.

But I am hoping the GTR strut brace clears the new manifold :p

[Milkmun]

Reverse cowl 😂 

[The Bogan]

12 hours ago, Milkmun said:

Reverse cowl 😂 

VN Group A bonnet buldge 🤣🤣🤣🤣🤣

[GTSBoy]

6 minutes ago, The Bogan said:

VN Group A bonnet buldge 🤣🤣🤣🤣🤣

C'mon! At least come kicking and screaming into the 2000s. BA XR8 bulge.

[Kinkstaah]

21 hours ago, Kinkstaah said:

The old manifold was quite under the GTR strut brace. 
The new manifold is quite [unknown] the GTR strut brace.
The GTR strut brace was needed to clear the bonnet vents.
The Old strut brace will almost certainly clear the new manifold, but not the bonnet vents.
The old strut brace will almost certainly clear the new manifold, and the new bonnet without vents.

But I am hoping the GTR strut brace clears the new manifold :p

The GTR strut brace clears the new manifold.. by about 0.5mm.

So this means I need to buy an OEM GTT Strut brace (again), which will clear the new manifold, but not the bonnet vents. I guess I can sell the GTR Strut brace with the bonnet with the vents as a package deal as someone will need this one day.

So my choices are vented bonnet but no strut brace, or GTR Bonnet with OEM brace (which I have to buy) but is bright red instead of the same colour as the rest of the car, which means the entire front end of the car will just be red until it goes back to paint jail.

In other news the engine starts and doesn't leak. Why both O2 narrowband sensors think the tune is rich AF I do not know. The idle is also pretty shitty and my expensive IAT sensor from the USA is dead.

The car sounds awful. But I assume or at least hope this is due to the many exhaust leaks, and the concrete garage it is in, sitting there with 0 intake bolted to it, and no bonnet or panels or anything to stop the induction/intake sound which is about 200db.

[GTSBoy]

7 minutes ago, Kinkstaah said:

Why both O2 narrowband sensors think the tune is rich AF I do not know.

Probably the cam.

[Kinkstaah]

That's the thing. Cam is smaller than before.. though the old cam was +6 degrees advanced. We're talking huge changes here, the narrowbands want to trim out 20% of fuel and pull the (wideband) idle to like 16.0 AFR or such. One side is a little more trimmy than the other. Think along the lines of ~20% to ~15-18%. Unfortunately my scouring of the internet hasn't really found anyone with this issue. People either just disable NB's or have them wildly different, where one is -20% and the other is +20 or 0 (i.e a sensor is just dead/wiring is just busted).

Turning them off and relying on the base map only results in the wideband reporting at about 14.0 with the Varex closed. It'd be a little leaner (closer to 14.7ish) with the Varex open.

I know I can just change the switch points so that the narrowbands agree with the wideband, but it's still odd. Both of them are reading voltage, it's just that they're reading quite high mv, in the ~800 region.

It's just odd. This was with the IAT fudged to report it was about ~22 degrees which is my guesstimation of the temperature in the room. I have an OEM sensor ready to try tonight, which is slow and crap - but .. worked last time I used it.

Sadly I am aware that idle tuning with the big TB is going to be a PITA and I look 'forward' to many hours spent stalling or stumbling idle or delving into drivability things.

[The Bogan]

The larger TB I had on the SS was a pain to get to idle right, but, that was cable

In the end they just raised the idle up a couple of hundred RPM so it was happy idling away either in gear or in park (slush box life)

I'm curious on how my NC will idle with the new intake, larger TB, and cams that are currently going in/on, but I have faith that MX5 Mania will sort this "electronical" "black magic" out the best they can in the tune with a electronic TB

Sometimes I wish I knew more about the intricacies of tuning, but most of the time I don't because I know it would hurt my brain 🤣

[Duncan]

22 minutes ago, The Bogan said:

....Sometimes I wish I knew more about the intricacies of tuning, but most of the time I don't because I know it would hurt my brain 🤣

That's the thing....the basics of fuel and ignition are deceptively simple.....getting it to behave like factory in all conditions after airflow mods is way more complex. Newer cars like the V37 are all about modifying the standard ECU which is about a billion times more complex than they were 20 years ago, with a bunch of parameters affecting others

[MBS206]

Grab a temp probe, and probe each exhaust inlet runner with it sitting idling. Each one should be pretty darn close to the same temp. If you've got some reading higher or lower than the others, it's likely either air flow isn't equal, or your injectors aren't equal to each other.

 

The other things to check, is from the wiring changes that were made, were any earth's or grounds moved/changed.

 

Lastly, for the strut brace issue. It's not perfect, but can you get away with slipping a washer or two under the strut brace to raise it, and it still clean the bonnet? If you can, work out the height you need, that the motor can't torque up into, and get a spacer made for each side.

[MBS206]

5 hours ago, Duncan said:

That's the thing....the basics of fuel and ignition are deceptively simple.....getting it to behave like factory in all conditions after airflow mods is way more complex. Newer cars like the V37 are all about modifying the standard ECU which is about a billion times more complex than they were 20 years ago, with a bunch of parameters affecting others

I was chatting with an ex SAU person who is involved in chooning euros now. He was saying the factory cars like Audi VW etc have something like 2000 tables that the ECU uses for getting everything "just right". Compare that back to any aftermarket ECU, and you'd be hard pressed to surpass 50 lookup tables.

Even the Ford Barra engine has a few hundred lookup tables to run it (and they're still working some tables out too!)

[Kinkstaah]

15 hours ago, MBS206 said:

Grab a temp probe, and probe each exhaust inlet runner with it sitting idling. Each one should be pretty darn close to the same temp. If you've got some reading higher or lower than the others, it's likely either air flow isn't equal, or your injectors aren't equal to each other.

The other things to check, is from the wiring changes that were made, were any earth's or grounds moved/changed.

Lastly, for the strut brace issue. It's not perfect, but can you get away with slipping a washer or two under the strut brace to raise it, and it still clean the bonnet? If you can, work out the height you need, that the motor can't torque up into, and get a spacer made for each side.

Good idea on the temp probe. The mv readings of the O2 sensors are very similar to one another, as is the injector pw. I went through logs in the past to see if there was a discrepancy and there is. Because they alternate up and down as narrowbands do.. they do often 'switch' as to which one is more. They were never 20%+ (more like 1-2%) so it's possible the difference between 20 and 15-17% is a similar discrepancy to 2.0% and 1.7% which I wouldn't have really noticed in the past.

We did think about spacing the strut brace. Unfortunately the ~20mm that the GTR brace is lower than the GTT brace is effectively what you need to clear the vents. Moving it up would make it very uncomfortable, but it's plausible that 10mm is a unhappy medium between both hard places...

The good news is.. using MR HAMMER it was actually pretty easy to bend back the bent bits to make sure the guard and headlight/new headlight tabs line up right. Yes, we used a R34 GTR guard to make sure the bolt holes all lined up with a known straight guard.

As above, you can see the side skirt and the GTR guard are not meant to play together, but everyone seems to think this is a simple fix to the point where nobody who has had these talk to one another mentions how...

...so I'll just assume they know how to fix it when it comes to paint jail time again. Whoever they are. Nobody returns my calls.

There's so much changed with regard to the ECU and the car.. that the next step really is to connect the scanner and attempt to drive the thing. It'll be pretty clear pretty fast how in or out everything actually is...

[GTSBoy]

22 hours ago, Kinkstaah said:

That's the thing. Cam is smaller than before.. though the old cam was +6 degrees advanced.

That's the thing. Especially at idle, changing the cam angle by that much could be spewing more fuel out the exhaust courtesy of everything happening that bit later. More fuel also means more air (if the fuel didn't burn, then neither did the O2) and so the O2 sensors can start to tell interesting but misleading stories.

And the specifics of what is happening could easily be affected by everything else you changed as well. And it could be dynamic, where a few revs more or less could somewhat change how the engine is breathing.