NX GTi-R: Version 3

What Happened! And Start Collecting Parts!

by Frank Ewald

There has been silence in my garage for almost a year. The NX GTi-R, when you last saw it, had rod knock and was parked until I had the time to work on it. Life intervened and many things have caused this project to get pushed to the background. Resulting in the car literally being pushed from one resting spot to another. When my NX first appeared on MotoIQ in 2009, it was as an 87 whp weakling. I have showcased the highlights and the challenges that the SR20DET engine swap led to - and not only did this swap highlight the weaknesses of the car but also my weaknesses as an automotive mechanic/engineer. No surprise there, because one thing I know is that I am neither an engineer nor a mechanic. I am simply a guy who bought an odd looking car in 1992 because it looked sporty and it had a T-Roof. And then I got hooked on it as you have been able to see through the articles that I have written over the years. However, rod knock literally knocked the enthusiasm out of me. Pun intended. I knew that it would be rebuilt, but when or how was all gray and foggy.


Do you know why you love your car? I don't. And right now it is very much a love/hate relationship. I do love the way that it looks and sits. However, I am tired of the high level of mechanical work that it requires. Due to life getting in the way, the car has sat unloved for the past year!

Upon tear down, there was more mayhem in the engine than I thought would be found, but there were answers to a lot of questions. First off, why did my engine fail? This was a huge concern not only to me but also to Dave Schlueter, my engine builder. What we found was that this was a problem that started about three years ago. Literally.  Heading up the back straight at Mosport (now CTMP) I did a money shift. For readers not familiar with this term, picture red lined in fourth gear, trying to grab fifth, but finding third instead. That forces the engine well beyond the redline and, I don't care how fast your reflexes are, if the engine is an SR20DET then you are going to pop a rocker. At minimum. That happened to me. AKA the Money Shift - because it is going to cost money! 

Opening the valve cover we found the rocker sitting between the two cams. Hauled the car home and went over everything including removing the lower oil pan, and rejoiced that this was a lucky one. No bent valves. No evidence of damage at all, in fact. After giving the engine a thorough going over, we turned it over by hand, and then finally started it. Oil pressure was very low for 15 seconds, then back to normal. Racing continued. Daily driving continued. The oil pressure continued to be low on start and then be normal. That was three years ago. I did not think there was any connection when the car developed rod knock in the spring of 2015. But there was.


Your eyes are not deceiving you. That is the front cover that contains the oil pump. The oil pick up from the pan bolts to the bolt holes seen on the left side of the picture. And you can see the crack. You can also see in the middle of the picture where a cast guide has been broken off. Based on the discoloration, it would appear that there was a 3/4" crack from the bottom up.
At the top of the picture, on the face of the housing between the two bolts, you can see the marks left by the timing chain. The chain didn't skip - it just jumped and cracked the housing back in 2013. That crack caused low oil pressure for the first few seconds of start up, and then everything was fine and normal. Tells me that the GTi-R oil pump is a pretty good unit. However, that crack, which wasn't visible even when we took the lower oil pan off, broke completely through last May. And that caused my catastrophic engine failure.
Dave and I have accomplished an incredible amount of work in this shop. This year was no exception. As I have moved to British Columbia, I had pressing time committments and so long hours were put in at the shop.

With the engine out of the car and on the engine stand, we pulled the upper oil pan off and we saw that the oil pump - which was installed new in 2012 - was broken. Literally broken. Could not believe this. I have never seen it happen. As we pulled the timing cover off and looked closer Dave saw the tell tale marks of a chain hit, coupled with a missing protective tab, that indicated that during that money shift the timing chain had somehow bounced, hit and cracked part of the oil pump three years ago! The discoloration variations of the cracked aluminum verifying the time difference between the initial crack (thus the low oil pressure on start up) and the complete break and loss of all pressure, resulting in rod knock on the third cylinder. Obviously, three years ago if I had pulled the engine this would have been prevented. But if it was just a keeper blocking the oil pressure sensor, which I wondered if that was happening, then that would have been a lot of work for almost nothing. Regardless, in the future my engines will be pulled.

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Wednesday, May 18, 2016 12:53 AM
I'm loving this!can't wait to see what's next!
Wednesday, May 18, 2016 6:41 AM
What ring gap did you go with for your top ring and middle ring?
Chris "Shaggy" Allenlink
Wednesday, May 18, 2016 8:40 AM
Your correct about the work for putting a VVL Head to a GTiR is the most involved when it comes to VVL head swapping ... The RWD is much more simple... The GTiR needs you to open the had up to fit the larger dowel centering pins.. Though you do not need to open up the bolt holes anymore.. Going M10 to M11(gtir) still fits through the VVL head just fine... External VVL passage is simple to do too... At the end of the day the deal breaker for the GTiR Head is shimming it ... Shims are hard to find so a 5.5mm hallow punch can be used to punch out feeler gauges to set clearances..... My 1st engine build was a GTiR Back in 1998 in my B14 and then was on the cover of SCC in Sep 2001 .. 501WHP 445ft/lb TQ ... It is a awesome motor.. It was my engine that prototype the cams at JWT for the 54C ... Good to see people are using them and they made a good difference !
Wednesday, May 18, 2016 11:11 AM
Thanks for your post Chris! I just went back into my stack of old SCC magazines and reread the article with your car in it. That was an impressive build.
Wednesday, May 18, 2016 2:34 PM
hi Chris...interesting comment regarding punching feeler gauges to set clearances on the 54C...ive tried this a few times and have always found the material completely squashed and destroyed when the engine was reopened for inspection...any thoughts on this?
Thursday, May 19, 2016 3:50 AM
23kid, I'm looking forward to the next step also. Currently the car is getting ready for a train ride west. Then time for the ECU, injectors, and tuning.

JR, I'm sorry. The amateur mechanic in me heard Dave tell me that, but I didn't record it.

Chris, that's fantastic to know the history behind the JWT cams. I cannot even imagine how many times you had them in and out of the car. That must've been both exciting and frustrating at the same time. I'll be touching base with Fly'n to see if I can get a scan of that article! With the shims, not sure if this will help you Winston, I had one engine apart that had very large shims. Saved them all. In 2012 I couldn't find an ideal one for the build. Took a die grinder and a steady hand to shave one a bit. Held up well. This build had to do the same to a couple. So ...
Thursday, May 19, 2016 12:28 PM
Forgive me if it's been mentioned (it probably has and I most likely forgot), where in BC are you moving to? I am assuming somewhere in the Okanagan such as Kelowna or Kamloops?
Thursday, May 19, 2016 8:08 PM
Leon, I'm in the Fraser Valley - Close to family.
Friday, May 20, 2016 7:42 PM
The 54c's a great engine, its a shame they mated it to such a average gearbox in the RNN14. Forgive me if I have missed an explanation in the article, but why is the CHRA oil return at 90 degree's and not a straight shot to the return. As for the shim discussion, certain Harley Davidson engine ones interchange and can be used.
Chris "Shaggy" Allenlink
Saturday, May 21, 2016 11:04 AM
About the punching of the gauges ... My buddy did the same not long ago and he said he had the same problem... Though I had put over 100k mi on mine and had no problem .. I suspect the quality and hardness of the feelers have been changed.. We both used the same craftsman part numbers too... It was odd now that you say you had the same problem... FRSport shows they now have the shims but who knows how long that will last ... Its just best to switch to a VVL head as its more maintenance friendly and does not ping as easy once the cam is on the high side .. Though T2 Turbos need to have big external gates and a good exhaust manifold for them to even start to work as expected .. I was just out in AZ tuning my buddys VE+T with a GT29 on external gate on a heavy P11 chassis and at 12PSI i ran away from my other buddys P11 on a GT28RS at 18psi .. Both cars I tuned on MegaSquirt ECUs that I build ... VVL Heads and boost are amazing..
Thursday, May 26, 2016 12:46 AM
Loagz, good catch on the oil return. That photo shows poor placement, it should be at the bottom, and will be evident in the next article.
Thursday, May 26, 2016 12:00 PM
--For 54C shims, if you want to pay the premium.

I am planning a 54C build, in N/A flavor, and I cannot re-use my old stuff since valves will be replaced. New guides, new everything in the valvetrain. I want to do +1mm Intake and Exhaust valves, high compression 12.5:1, 88mm bore build. I found a machinist with a proper rockwell hardness tester, used a few of my old shims as an example and found a matching material to use to make my own shims. I saw Chris Allens video about how to shim the 54C head, and wanted to keep the OEM shims. Or I may convert to DET valvetrain equipment if I am not satisfied with the shim ordeal.

The 54C rocker arms, water pump and oil pump and lower oil pan can still be ordered through Nissan Competition as well. I just ordered some recently.

Thank you for posting and hosting a 54C build as this engine is by far the most neglected engine in the SR20-family.
Chris "Shaggy" Allenlink
Friday, May 27, 2016 7:21 AM
Why would you use a 54C when you can use a VVL head .. It will make way more power then a 54C and it's simpler to work on ... Also 12.5:1 is hard to tune on DE heads and not even a problem on a VE on 91oct ... I have tuned VEs at 13.1:1 on pump gas ... The Orange Dataun roadster with the VE and ITBs is at 13.1:1 CR and works fine on pump gas
Friday, May 27, 2016 7:52 AM
54C uniqueness. (as Frank has mentioned in his lovely article)

Question, how easy is it running 13.0mm lift camshafts in a VE?

Chris "Shaggy" Allenlink
Friday, May 27, 2016 8:31 AM
Hmmm ... Maybe it's just me .. I have been dealing with 54C stuff in my car for so long it's kind of like whatever ... I don't think you can work any DET head enough to flow what a stock VVL head flows ...

13mm cams for VE is an off the shelf cam from Kelford ... There more to cams then just lift ... For example how long you can leave a valve Open for after BDC on compression stroke before you equalize flow of scavenging vs compression ... That's just one example of many. It seems like to make more power you need to run a lot more overlap. So much so when we tested the VVL down at JWT we made the most power at .040 piston to valve clearance .. This was around 105° of overlap ... I don't think you would have a chance in hell of an engine of a four-cylinder even starting with that much overlap ... That's why it has 2 profiles ... It's a no brainier best of both worlds ... Though I've never tried so who knows maybe it will ...
Friday, May 27, 2016 8:49 AM
The only issue with that is the ports are made to run on high lobe all the time...

Like how the VE valves are undersized -1.0mm intake and exhaust from stock SR20DE/T because those giant ports cause disruption and are not ideal for cylinder fill... But the 54C is more ideal for cylinder fill since the air is no longer bending so harshly on the radius to get into the combustion chamber. Lots of difference in all the engines. Sometimes one powerband is (insert adjective here) than two powerbands ...

With the VE, from what I gather, you need to start modifying the rockers to get big boy lift cams...

54C uniqueness is fun. Thanks for the brainstorming in this article.
Sunday, June 12, 2016 4:16 PM
Awesome article & good read.
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