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Crazy, isn't it? Most piston damage from cracked ringlands I've seen on the forums are small or pieces come off. Mine cracked and melted.
I wonder what your EGT's would have looked like on that cylinder. I'm going to guess that was a defect in the piston or something, and that exacerbated the issue. It's one for the "trophy" shelf for sure!
 

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Discussion Starter #182
I wonder what your EGT's would have looked like on that cylinder. I'm going to guess that was a defect in the piston or something, and that exacerbated the issue. It's one for the "trophy" shelf for sure!
Some valves got bent. The EGT may be the cause due to the exhaust valves being stuck open causing a lean condition.
 

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Discussion Starter #183 (Edited)
I got my car back! Now for the painfully slow and boring break in for another 1000 miles. Turbo response is a lot better and vacuum is down to around 22-23 inhg. It was sitting around 19-20 inhg prior to short block swap. Off boost response is better and spool is quicker to 8 psi, as in boost spike quick. It will get retuned to take advantage of the increased compression (stock 8.2, now 9.0). I'm so glad she's back home!



The engine and engine bay is cleaned up. It looks like a new car again. Big thanks to Mike and Dylan of Infamous Performance in Escondido, CA for an excellent experience and on-time as promised completion date.

Now for the break-in.
 

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Discussion Starter #186
This break-in is going to take a while. I went through a tank yesterday of my left over ethanol and 91 drove 211 miles down to 1/8 tank. Today I drove for an hour with about 15% ethanol and a full tank and covered 40+miles. I took it to the winding roads up near the mountains. I subjected it to different loads, gears, under 8 psi of boost, and plenty of engine braking as per my engine builders recommendation. It's almost as fun as revving the motor to redline like I normally would driving through the mountains. I guess break-in isn't that bad as I thought it would be.
 

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This break-in is going to take a while. I went through a tank yesterday of my left over ethanol and 91 drove 211 miles down to 1/8 tank. Today I drove for an hour with about 15% ethanol and a full tank and covered 40+miles. I took it to the winding roads up near the mountains. I subjected it to different loads, gears, under 8 psi of boost, and plenty of engine braking as per my engine builders recommendation. It's almost as fun as revving the motor to redline like I normally would driving through the mountains. I guess break-in isn't that bad as I thought it would be.
It'll be over before you know it, I've had to break a couple engines in, and it's always so daunting initially. lol
 

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Discussion Starter #188
The GR stumble is back with a vengeance. I will be experimenting with a fuel line damper with a vacuum/boost port. The Cobb fpr vacuum reference relocation kit didn't do anything. It is getting really annoying to drive my car, especially trying to break-in the motor.
 

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The GR stumble is back with a vengeance. I will be experimenting with a fuel line damper with a vacuum/boost port. The Cobb fpr vacuum reference relocation kit didn't do anything. It is getting really annoying to drive my car, especially trying to break-in the motor.
Wait, so you're running the older version FPR and still having the issue now?

You are pro tuned, right?
 

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Discussion Starter #190
Yup, older fpr and protuned. But it was protuned with a motor on it's way out. It stumbles from 2500-3500 on part throttle from 2nd gear and up. Even more on up hills and very light throttle. Hopefully it goes away after retune on higher compression.
 

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Yup, older fpr and protuned. But it was protuned with a motor on it's way out. It stumbles from 2500-3500 on part throttle from 2nd gear and up. Even more on up hills and very light throttle. Hopefully it goes away after retune on higher compression.
If you're on a Cobb AP, can you open up Access Tuner Race and look at the map values at all? I would take a look at the load compensation tables and see if they are out of whack. Cobb's stage 3 has both TGV open and TGV closed zero'd out on their stage 3 map (with FPR/pump/injectors/relocation of FPR reference line). I was running 20% in my map until I relocated my FPR ref. line and ended up zero'ing all the tables out, haven't had any issues.

Hope you get it sorted out! If not... maybe time for a rail/FPR upgrade :)
 

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You can always take a nice long drive up to Julian. Best path I found for that was up I-15 to I-76. Take I-76 east to I-79 south and then I-79 into Julian.

I believe round trip from San Diego was about 200 miles or so, and perfect stopping point in the middle with some awesome sandwiches in Julian.

Another decent way is taking I-8 east to I-79 north and go backwards.

If you really want to pile on the miles, you can take I-76 all the way to/from I-5.


I would definitely get the stumble sorted before driving this route as there are a lot of tight turns and elevation change which would result in light to no throttle.
 

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Discussion Starter #193
You can always take a nice long drive up to Julian. Best path I found for that was up I-15 to I-76. Take I-76 east to I-79 south and then I-79 into Julian.

I believe round trip from San Diego was about 200 miles or so, and perfect stopping point in the middle with some awesome sandwiches in Julian.

Another decent way is taking I-8 east to I-79 north and go backwards.

If you really want to pile on the miles, you can take I-76 all the way to/from I-5.


I would definitely get the stuble sorted before driving this route as there are a lot of tight turns and elevation change which would result in light to no throttle.
I drove to Julian last weekend. I'm looking to do another drive again off the I-8 with a buddy this time. Thanks for the suggestions! What I really want is to vary the load on the engine keeping it under 8 psi, 4500 rpm, and doing a lot of engine breaking. That drive to Julian was just what I was looking for.
 

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Discussion Starter #197 (Edited)
Break-in complete. Fresh new oil change. She feels powerful again. Now focusing on the stumble and preps for retune. I'm liking the higher compression. The response is phenomenal. I would have loved to drive my car down Hakone Mtn if that were possible. It was a blast in my Hachiroku Levin.

Upon doing some inspection on the undercarriage, I found my AVO endlinks are not cutting it. Front driver side endlinks lower bushing broke in half and the passenger side rear end link sway bar sheared the nut off and stripped the threads one the end links, rendering them useless. I will not buy them again.
 

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Discussion Starter #198 (Edited)
Looks like my old Rallitek end links will go back on. I'm not going back to solid end links anymore. I guess I broke the AVOs while breaking in the engine in the mountains. The stumble seemed to smooth out with the new A/F ratio sensor. I shook the Denso (which was only 3k miles old) and it rattled. It was replaced with an NTK. So far so good.
I'm guessing that the cracked ringland+oil consumption killed the A/F sensor in short time. It was disappointing when I was getting it tuned and was informed by Bill the sensor was bad, and I had just replaced it. The NTK had to be set up to fit for the bracket opposed to the Denso. I'm disappointed in Denso as they were my go to parts for my old Toyotas.
 

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Discussion Starter #199
The stumble is still there, but not as bad as they were. Just waiting for my AN fittings to arrive. I'm experimenting with a fuel pulse damper from Radium Engineering.
 

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Discussion Starter #200
I installed the fuel pulse damper but removed it due to static leaks at the fuel gauge port and the fragola 90 degree swivel. I did notice at idle, the short term fuel trim went more negative, suggesting it was running richer. Just now waiting for more fittings to reconfigure the fuel lines.
 
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