RH9 R32 GTR Build Thread

[OST Micah]

Got a bit more done this past week. Added in an exhaust pressure sensor. I had it in the wiring harness in case I felt like adding it one day so just did it now. Never watched this data before on any car so that'll be nice to see and learn from.

 

Next up was a mount for my pressure sensor bank. I found this machined sensor bank online and thought it was a really cool piece. The first few ports are one chamber and then each port after that is a separate chamber. This allows all the pressure sensors to be mounted in one place for easy changing. There are multiple 1/8" npt fittings per chamber. Made a mount for the bank that doubles as a battery tray.

 

Installed my throttlebody and inlet pipe.

 

Next I'll be getting the radiator in and doing some wiring changes for the DBW. All wires were run in the new harness I made earlier, they're just not terminated. 

[OST Micah]

LHD 350Z pedal mounted with a custom bracket. Pretty simple bracket, can't get much easier than this. Still had t tweak the pedal rod a bit to get the pedal to sit in the same spot. GTR pedal swapped over onto the 350Z rod.

[OST Micah]

Pressure sensor bank plumbed in and wired up. Fuel, oil, coolant, and MAP. The MAP section of the bank runs everything. MAP sensor, wastegate/boost controller, fuel reg, factory boost gauge, and BOV. It's supplied by a -6 line from the underside of the intake. This means there are now only two lines to disconnect under the intake; this -6 and another -6 for the brake booster. No IACV, and no vacuum lines. And no more vacuum line tees! Each part has its own line. 

 

Catch can installed. 

 

Picture of the turbo side of the bay. Power steering pump installed with the turbo on! Liking this manifold design a lot so far.

 

All back together. I'll make a turbo inlet that goes to a headlight duct at some point. Really happy with how his turned out though. Wiring is also complete as far as the bay goes. 

 

Close up of the coated covers and painted CAS sensor. Factory CAS has got me this far! 

 

 

[OST Micah]

It runs!

 

[OST Micah]

Outside under its own power in months. Only dove it to move it out of the way for another car to get into the shop but still felt good.

[OST Micah]

Some more progress. Got it on the dyno and tweaked the tune for the new motor and dialed in the idle control with the DBW. Gate pressure (24psi) and pump gas timing only. Going to enjoy it for a bit before going back to the track. A few things to do yet and I'll get it out of the shop. 

Edited July 24, 2022 by OST Micah

[OST Micah]

Drove the car to and from work nearly every day last week. Switched it over to street mode in the evenings. Front half of the cage out, headlight in, other set of wheels on. No issues and just having fun driving it.

[soviet_merlin]

I love how you have the photos from the same angle in the same spot. It is such a big contrast. One looks like serious business and the other is as understated as a GTR can be.

[OST Micah]

On 7/31/2022 at 4:28 AM, soviet_merlin said:

I love how you have the photos from the same angle in the same spot. It is such a big contrast. One looks like serious business and the other is as understated as a GTR can be.

I didn't notice that. Definitely looks that way. I love the sleeper look myself but you gotta do what you gotta do for the track.


Nothing crazy to update. Just been enjoying the car, driving it, cleaning it. Stuff I don't normally get to do. But the other day I decided to start tackling my power steering issue. Ever since I got the car at port the steering has had very minimal power assist. At idle it has none. Around 3000rpm it starts to have a bit. Fine for driving but really annoying when parking. The worst is when staging on the prepped surface of the track and having to shift the car over in the lane.

Two years ago I installed a used pump that was said to be working. There was no change in steering feel. Figured that meant something else was the problem. Played with bleeding, refreshing parts of the pump, etc. Nothing changed. I just lived with it and always worked on it in the back of my mind. Every now and again try something on the car. Always the same result.

Yesterday I thought I had it figured out. A clogged high pressure line. Test fitted another and again no change. Blew the rack, lines, and gear assembly out with compressed air looking for a clog. No change. 

Next I read through the service manual and decided to test this "good" pump. Rigged up my own tester with a nitrous pressure gauge feeding to the Haltech through the EMAP sensor wiring. With the high side open there was 80psi. With the high side blocked only 200psi. FSM says 900psi. So much for "the pump worked great".

Now I know there are a few aftermarket pump kits out there and I have nothing at all against the people that sell them. I just prefer to do my own work and/or spend as little money as possible. Their kits are very nice and well worth it if you cannot make it work on your own or don't want to modify the actual pump.

Online pictures showed that the 2004 Sentra pump looked extremely similar to a cut down single stage RB26 pump. Got one locally to measure and compare. Amazingly, the two pumps are almost identical. Kind of bizarre how close they are. Only a few modifications needed to fit the Sentra pump.

1. Backing plate needs milled down just like it does when converting an R32 GTR dual stage pump to single stage. 
2. Pivot bolt hole needs to be drilled out. GTR pump is .413" ID for the shoulder of the bolt. Sentra pump is threaded for an M8 bolt.
3. The body of the pump is larger. This means the plate that bolts to the front of the pump and grabs the adjuster slide does not fit around the pump body. Nor do the bolt holes line up. Fill the bolt holes (weld), open up the cutout in the bracket to fit around the pump body, and redrill the holes in the new correct location.

Other than the above it's a straight swap. Pulley lines up with the crank drive (R32), pump inlet and outlet are the same as before, pulley splines and fitment on the pump are the same. Really wild.

I now have working power steering at idle! Been years in the making. 

Pump even looks the same.

Backing plate notched like the previous pump.

 

[hattori hanzo]

I had a similar issue with my power steering and it came down to the incorrect dash fitted, it has a speed sensor which talks to the power steering to load up pressure at low speed for parking and the like.

 

 

[OST Micah]

Took the car to a local airport event to shake down the new setup. Just wanted to make sure everything was working as it should.

Good thing as there was a pretty oddball issue. Truthfully it had been noticed a few weeks prior but was inconclusive on the cause. During tuning I had to add an enormous amount (about 30%) of additional fuel. There were no significant parts changed; just a refreshed motor and new turbo manifold so I knew something was wrong. Replaced the fuel pumps, cleaned the fuel filter. inspected all lines, etc. Nothing made a difference. Took the regulator apart to inspect, used shop air to ensure it was adding pressure 1:1; no issue there. I was stumped but the car ran well so I went racing.

At the event I turned up the boost from gate pressure and fuel pressure was falling out dramatically. Tried to make the car run just to have fun at the event but no dice. Got some decent photos though. 

Got the car back home and starting thinking it over and reviewing logs from last year and this event. I ended up grabbing a large return orifice fuel regulator from another car and adapted it to test on mine. Boom, fantastic fuel pressure. All fuel added had to be removed. Ordered up my own regulator of the same style. I still have no idea why the regulator worked with the same pumps for 3 years and at the same power level for 1-2 years without issue but this season it no longer could flow enough. It must have just been on the edge before and something tipped it over.  

With that problem solved the car went to a track rental to try to dial in the clutch again. Hadn't gotten a handle on it last season. Thankfully, with a new launch and clutch slip strategy, the clutch was sorted in a couple launches. 

Unfortunately, I could not get the car to go into 3rd gear at WOT. Reduced all torque from the motor on the shifts and still nothing. Did manage to get one pass out of the car on lower power (see the low MPH) and the clutch was dialed in so I called it a win for the day and for a new setup. Drained the fluid later and found broken 3/4 shift springs so that'll be corrected this weekend.

Car now does consistent 1.39-1.40 60fts every time the track holds it. And all I have to do is dump the clutch and let the slipper do the work. Super happy about that.
 

Aborted pass due to missing a gear but the 60 was great.


Complete pass

Pass of the slip above

 

[OST Micah]

This winter I took the car apart again. Saw some things I wanted to change. 

First was to get rid of the VCAM and try a set of high lift cams. It'll be a good test to see what a set of big cams will do over a set of drop-in cams. Tomei Japan +1mm buckets and stud kit as well.

 

I also decided that if I was going to add lift it would make sense to do a pocket port on the head. Exhaust side too but hard to get pictures of that since it's all black with carbon.

Then I port matched the head to the intake. Really far off. Had to open it up a lot.

 

Then the valves were unshrouded and the chamber opened up. I was having trouble putting timing into it at 35+psi. Hopefully this is why. We did something similar on one of our Gen3 Hemi motors and it worked very well.

Head is done for my part. Going to the machine shop for cam clearance and valve job.

 

Next I pulled the oil pump apart to inspect and port. The screws had been installed with loc-tite by the machine shop a couple years ago and I had to use the torches to get them out hence the burned oil; not from the motor.

Pump outlet

Pump suction

Backing plate installed with torx-head bolts this time for servicability.

 

Going to be putting it back together as soon as the head is back from the machine shop. Looking forward to testing the head changes and the open chambers.

Edited January 24, 2023 by OST Micah

[OST Micah]

Head is back from the machine shop.

 

Got it assembled and buckets shimmed up. Torqued to the block for shimming as it does make a difference.

 

The rest will be going together ASAP.

[GRKGTR]

Interesting that you got rid of VCam, why was that exactly?

Loving the updates!

[OST Micah]

21 hours ago, GRKGTR said:

Interesting that you got rid of VCam, why was that exactly?

Loving the updates!

Thanks!

Well there's a couple reasons there. First, I wanted to try high lift cams (for power and to remove more on the exhaust stroke). I also wanted to have a fixed cam because at high RPM the cam would move around several degrees. Maybe that was incorrect PID tuning or maybe it was the cam gear not able to properly lock. Either way, I wanted to eliminate that. Cam advance at high boost/RPM can probably really increase cylinder pressure. I'm really just trying to do everything to eliminate detonation. I will miss it though. Definitely made the car more drivable.

Sorry for only a few junk pictures. I was trying to get this thing done.

Added a Supertec billet backing plate. Another effort to increase oil pressure. Maybe the factory ones flex? Who knows. Worth a shot though.

 

Degreeing the JUN cams with a set of vintage JUN cam gears. I like the old school stuff. Got one of these on a motor I bought and another from a friend.

 

Motor complete and ready to go back in the car. Just ran out of time tonight.

 

 

Edited April 20, 2023 by OST Micah

[OST Micah]

All back together after a few days working after hours. Car sounds completely different. Bay and car are dirty but I'll clean them sometime soon. Going on the dyno at some point to do some testing and tuning. Lots of customer cars to do first though so it'll be a bit.

[Duncan]

Great to see it coming along.

It might just be the angle, but with the adapter the unprotected battery+ terminal looks crazy close to the earthed battery hold down bar....I'd hate to see this car burn to the ground....

[OST Micah]

9 hours ago, Duncan said:

Great to see it coming along.

It might just be the angle, but with the adapter the unprotected battery+ terminal looks crazy close to the earthed battery hold down bar....I'd hate to see this car burn to the ground....

Thank you and good looking out. It is indeed the angle. There's a couple inches between them. However I do need to stop being cheap and buy a factory terminal cover. Weird how those non "go-fast" parts seem expensive but "go-fast" parts not so much.

Edited April 27, 2023 by OST Micah

[OST Micah]

Fired it up a few days ago. No issues! A couple things to tidy up and then on to testing.

 

[OST Micah]

No real updates. Just waiting on a free dyno slot and some free time to tune the car/test on the dyno. Tweaking the startup and idle when moving the car around the shop.