RH9 R32 GTR Build Thread

[OST Micah]

Been sitting about 3 weeks now. Stinks but customer cars come first. I shined it up a bit though one evening. Really anxious to get it on the dyno.

[OST Micah]

While I'm waiting for a free spot on the dyno I figured I may as well do something productive with the car. Last year fuel pressure was dropping out on ethanol (fine on gas). It wasn't plummeting and still had pressure enough that I could run the car but it wasn't right. The car only has -6/HICAS lines for supply and return so the first test will be replacing the supply line with a -8. Hopefully this takes car of the issue but if not, I made provisions for a third pump to be added.

This is what I started with. Sort of nice, but how the wiring came through the hat was not up to snuff.

 

Milled out the underside to get a nice flat surface for the bulkhead nuts.

 

Drilled out the factory wiring connector and potted it with three sets of pump wires. Currently only have two pumps but just in case. Also filled in the hole where the wires previously exited.

 

What it looks like in the tank. This y-block is much less restrictive than the setup I cobbled together before.

 

Installed. No sheetmetal cut or bent to fit 8an. And the steel cover fits with no spacers or modification.

 

1/2" hardline made up to fit in the HICAS slot. 

 

No pictures of the engine bay lines but nothing looks too different there. We'll see what happens! 

[Duncan]

Nicely executed mods to the factory hat there, they should be nice and reliable. 

You are probably aware, but there are aftermarket hats available these days too for higher flow lines and higher current connectors, eg from https://frenchysperformancegarage.com/collections/fuel-system-kits

[Ben C34]

Fuel will wick up through the wiring * inside the insulation) the way you have done that . It isn't sealed properly. you need bulkhead fittings to allow it to be properly sealed.

[OST Micah]

13 hours ago, Duncan said:

Nicely executed mods to the factory hat there, they should be nice and reliable. 

You are probably aware, but there are aftermarket hats available these days too for higher flow lines and higher current connectors, eg from https://frenchysperformancegarage.com/collections/fuel-system-kits

Thank you! 

Yes, there are a couple really nice hats out there. If this was a customer car I would be purchasing one of those. I'm just too stingy and if I can make a decent version myself I will at least give it a shot. 

Edited May 30, 2023 by OST Micah

[OST Micah]

Well it's been a while since I've updated as it's been a struggle.

Last November the few month old engine was torn down due to a rod bearing noise. The engine never lost oil pressure and on one partial pass on a brutally hot day oil pressure dipped to 58psi. It made no noises after the pass and there was nothing in the oil. Oil pressure Engine Protection was set to trip at 55psi. Later that week I tested a launch out on the street. It was about 38F out and I let the car warm up a bit but maybe not enough. Immediately after the launch I heard a light rod knock. Related to the short time of 58psi at high RPM or the potentially cold oil? 

While the crank was being repaired the head and cams we done as posted on the last page. Got the car on the dyno shortly after the last post. Did some light and medium load driving and all seemed well. Oil pressure was a bit lower than I would have liked to see but I chalked it up to the now larger main bearing clearance as they were the only bearing available at the time. After two partial WOT hits on wastegate pressure the oil was drained and the filter cut open. Nice and clean with no bearing material.

Fresh oil in and two more partial WOT hits just to watch oil pressure and changing gears to see if time, load, or RPM related. Again, a lower than I would like so I got some 40 and 50 weight oil to try - just to troubleshoot and see if it helped. Drained the oil and several large chunks of bearing material came out of the sump. This was seriously disheartening. Really frustrated with the car and myself at that point. Pulled the engine again a few days later to see where I was. 4 of 6 rod bearings were completely squeezed out of the rods like they were made of play-dough. Freshly repaired crank was beat up but likely repairable again. 

Bought a new crank to be safe, two new rods, and new rod bolts for all (old rods and crank are said to be fine by our builder so they will go on a shelf for a rainy day). New oil pump gears, new oil pump housing purchased as well. The old ones were beat up at this point. 

After tearing the engine down and sending it out the our builder I pushed the car into the storage building and took a break from it. Did house projects, built a garden, got chicken coops and chickens - just got my mind off of it. 

Yesterday the shortblock arrived. It was a bit unexciting as I had started to forget about the car which was nice. But back to work we go. 

 

This time I will be blocking off the relief in the oil pump and running an external adjustable relief. I will set the oil pressure to give the engine all the pump needed - looking for 100psi of oil pressure at WOT.

I will also make the sump more easy to remove by modifying the area that covers the rear bolts. This will be to change the oil pump should I need to and to check or replace the rod bearings on a regular basis. I'll also be adding a bung at the front of the sump to be able to access the pump relief should this external relief not work. Lastly, I'm adding a ClearView filter to keep an eye on the oil without having to cut the filter every drive, dyno hit, or pass. 

Sorry for the wall of text! I'll be chipping away at this over the next several weeks.

Marking center of the relief on the sump.

Edited September 16, 2023 by OST Micah

[Duncan]

Ahh that suck to hear, sadly these engines can be difficult for oiling, they don't call RBs Run Bearings for nothing...

What oil pump are you running?

I guess advice should come from your engine builder, but these days we run bigger clearances and heavier oil 20/50, the last engine in the car is the only time I've pulled it out before it broke...got 3 seasons from it

[OST Micah]

12 hours ago, Duncan said:

Ahh that suck to hear, sadly these engines can be difficult for oiling, they don't call RBs Run Bearings for nothing...

What oil pump are you running?

I guess advice should come from your engine builder, but these days we run bigger clearances and heavier oil 20/50, the last engine in the car is the only time I've pulled it out before it broke...got 3 seasons from it

Thanks, Duncan.

Running an N1 pump with Spool spline drive. I'd love a bigger pump but if I put trash through it the cost of another would hurt even more than the cost of the first. If the N1 simply cannot make the pressure (I know it can with slightly less bearing clearance on other builds) then I will bite the bullet and get a Nitto pump. Another reason I'm making sure the sump can be removed in-car.

Thank you for the insight. Yes, we are running larger clearances as the crank was touching the mains with stock clearances (first engine teardown). I think the larger clearance is likely why the bearing issues occurred. The first engine had stock clearances and 80-90psi oil pressure at high rpm and 10-40 oil. The second engine had around .0023" main bearing clearance and 75-80psi oil pressure at high rpm and 20-50 oil. When I rebuilt that engine this Spring it had .0028" main bearing clearance and 65psi oil pressure with 20-50. As the clearance went higher the pressure went much lower. Most of the people involved in this (including myself) are V8 engine guys and 70psi or even 60psi of oil pressure is no problem for those engines even running into the 8s at 4400lbs. But I am guessing that for our little engines and tiny rod bearings it's just not enough. That's why each engine lasted a shorter time with less oil pressure. This new engine has .0022" mains and I will not run it up if I cannot get 90psi+ oil pressure at high RPM.

For oil it was broken in on Lucas 30wt break-in oil. Drained, filter cut, and 20-50 was used. Never got to try the 40 and 50wt. Going to use 10-60 this time after break-in. Maybe 10-60 with some 40 or 50wt to get the cold viscosity up if needed.

Edited September 17, 2023 by OST Micah

[OST Micah]

Oil pump porting. 

 

Spool spline drive gears

 

Backing plate bolted back on with torx-head bolts. These get harvested from Gen3 Hemi oil pumps before throwing them away.

 

Modified for an HKS trigger kit.

 

The threaded relief cap that was used to find center on the oil pan is reused here. Took the spring out of the pump, wound a long bolt into the threaded cap and snugged it up tight. Then welded it in place and cut off the excess. This blocks off the relief entirely so the external relief can do the job instead. In case this doesn't work, I'm adding a 20an bung to the pan just below the cap to access this.

[OST Micah]

Pump relief access bung added. Welding didn't go so hot on this one.

 

Two -10 bungs added to the side: upper for head drain that will be going on, lower for external relief return. This lower bung has a 1/2" tube welded to it prior to being welded to the sump. This tube gets the relief return oil as close to the pickup as possible. Hopefully this replicates the factory relief return well enough.

 

Sump is now completed and the engine can start going together.

Edited September 28, 2023 by OST Micah

[OST Micah]

Here we go again...