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jcbrx8 01-30-2019 08:06 PM


Originally Posted by RotaryMachineRx (Post 4880078)
No, against all good advice I never did install an inline filter. My theory is...

I'm not saying you need to change where you are feeding your oil (obviously cleaner is better), it will work just fine the way you have it.

Yes, separate topics:
I'll say given the source of your oil feed I agree w/ the "good advice"..., but hey you're doing something right. :icon_tup:

Yes, I understood your suggestion as incorporating the sandwich plate with the reloc kit. Thx.

skc 01-31-2019 06:54 PM

Look up the Hymee remote oil filter. I have it running on my car

jcbrx8 01-31-2019 10:53 PM


Originally Posted by skc (Post 4880147)
Look up the Hymee remote oil filter. I have it running on my car

SKC, Searched, but didn't find anything. Can you post a link?

jcbrx8 02-01-2019 01:03 PM

Progress update: Freeze plug delivered...and installed. Engine s/b going back in over the next few days...


https://cimg6.ibsrv.net/gimg/www.rx8...f01517f3f7.jpg
Old and new freeze plugs...


https://cimg4.ibsrv.net/gimg/www.rx8...e758770ae3.jpg
New freeze plug installed...
.

jcbrx8 02-01-2019 01:16 PM

Given space re: the leaking oil pedestal...plan to take earlier suggestions to replace the reloc head unit inner o-ring and install the sandwich adapter in an effort to improve long-term pedestal oil sealing.


https://cimg8.ibsrv.net/gimg/www.rx8...d16c29d23d.png


.
.

jcbrx8 02-03-2019 12:49 AM

Progress update: The engine's back in. :ylsuper:

Next up dressing the bay...


https://cimg1.ibsrv.net/gimg/www.rx8...0e11beb664.jpg
Engine reinstalled
.

jcbrx8 02-05-2019 11:19 AM

Progress update over the weekend: Installed...
Below:
- DP & WG
- motor mounts
- compressor intake section

Up top:
- oil cooler feed & return lines
- pulleys & belts
- coolant hoses to coolant manifold
- AC compressor
- ignition coils & wires

Pretty mundane stuff...all installed w/ out issue.


https://cimg0.ibsrv.net/gimg/www.rx8...0ded81369e.jpg
Current state of bay...
.

jcbrx8 02-06-2019 11:34 PM

Update: Installed...
- oil pan
- WG boost control hoses
- oil filter sandwich plate
- oil filter reloc head unit
- oil filler reservoir w/ LIM valve solenoids


https://cimg5.ibsrv.net/gimg/www.rx8...ff8382e12e.jpg
oil pan, turbo drain, WG


https://cimg8.ibsrv.net/gimg/www.rx8...c47254c2c8.jpg
oil sandwich adapter and reloc head unit. No issue w/ sufficient space.


https://cimg1.ibsrv.net/gimg/www.rx8...a2aa8b78a1.jpg
.
current state of bay...
.
.

strokercharged95gt 02-07-2019 07:30 AM

Is that your drain line for your turbo on the bottom of the oil pan? If so, is that causing any issues (turbo smoking, etc)? I was always under the assumption that the drain line had to mounted above the oil line to keep oil from backing up into the turbo.... Other than that, I hope this all works out this time.

jcbrx8 02-07-2019 09:55 AM


Originally Posted by strokercharged95gt (Post 4880566)
Is that your drain line for your turbo on the bottom of the oil pan? If so, is that causing any issues (turbo smoking, etc)? I was always under the assumption that the drain line had to mounted above the oil line to keep oil from backing up into the turbo.... Other than that, I hope this all works out this time.

Yes, that's the turbo drain connecting at the rear of the oil pan. I didn't have any issues w/ turbo smoking before..., but you raise a good point. Even if not backing up to the turbo...I'd expect oil w/b standing in the line. I'll add some insulation in the area closest to the runners. Thanks.

RotaryMachineRx 02-07-2019 11:19 AM


Originally Posted by strokercharged95gt (Post 4880566)
Is that your drain line for your turbo on the bottom of the oil pan? If so, is that causing any issues (turbo smoking, etc)? I was always under the assumption that the drain line had to mounted above the oil line to keep oil from backing up into the turbo.... Other than that, I hope this all works out this time.


Originally Posted by jcbrx8 (Post 4880578)
Yes, that's the turbo drain connecting at the rear of the oil pan. I didn't have any issues w/ turbo smoking before..., but you raise a good point. Even if not backing up to the turbo...I'd expect oil w/b standing in the line. I'll add some insulation in the area closest to the runners. Thanks.

You won't have any issues since the turbo itself is mounted higher than the oil level. I have a similar turbo oil drain set-up.

jcbrx8 02-07-2019 12:40 PM


Originally Posted by RotaryMachineRx (Post 4880580)
You won't have any issues since the turbo itself is mounted higher than the oil level. I have a similar turbo oil drain set-up.

Yeah, I reviewed some of your build pics...very similar turbo drain routing. Thanks...good to know you've had no issue w/ similar set-up long term. :icon_tup:

Brettus 02-07-2019 01:24 PM

Hasn't been an issue for me either . A few people have had issues but I suspect that is due to the drain line being too small or not fitting a restrictor to the oil supply line.

jcbrx8 02-09-2019 03:56 PM

Progress Update:

- Good progress...couple of quick pics :)

https://cimg9.ibsrv.net/gimg/www.rx8...ab417432f4.jpg
Re-install pics...


https://cimg7.ibsrv.net/gimg/www.rx8...1fb6e7cb4d.jpg
...


https://cimg0.ibsrv.net/gimg/www.rx8...d7acb7df8c.jpg
...



jcbrx8 02-09-2019 03:58 PM

And some vids. Put about 40 mi. on her today ...so far. More detail to come...



strokercharged95gt 02-09-2019 06:27 PM

Engine sounds healthy. Good luck

jcbrx8 02-09-2019 08:16 PM

Returned from a second long drive. Currently at a little over 100 mi. and all seems well...

- I've a small coolant leak somewhere beneath my radiator feed or return that I'll have to chase down and resolve.
- No oil leaking anywhere.

:fingersx:

Below is a dash shot and a pair of screen captures from my OBDII phone app.


https://cimg2.ibsrv.net/gimg/www.rx8...97f2b70869.jpg
A little over 100 mi. in now...
.
.

https://cimg9.ibsrv.net/gimg/www.rx8...1d76049e25.png
Ave running coolant temp is 180-185F in 45F ambient temp.
.
.
https://cimg4.ibsrv.net/gimg/www.rx8...846f0bf76e.png
Temp and idle after idling in the garage ~ 5 min.
.

jcbrx8 02-11-2019 12:12 PM

So, a bit more detail surrounding my start-up & beginning engine break-in experience...

I took Fri. afternoon off work and finished the reinstall. Push started her and began driving around the block in my subdivision w/ no or little white smoke. About 7min in my coolant temp alarm goes off so I stop. No low coolant icon...no CELs at all. ??? :scratchhe I wait about 15 min. push start her again to drive home (around the block) and pretty quickly notice a good deal of white smoke!? :( Back at the house I'm perplexed :confused::
  1. Why is she putting out white smoke again... is it remnant assembly lube?,... or a coolant issue?
  2. Why is she overheating?
Honestly, taken together...I'm concerned...but I break for date night. Happy wife...happy life. :)

Sat. morning first thing I research how long should I expect assembly lube white smoke after a rotary rebuild? I find the below site which indicates"...Expect this to get into your exhaust and smoke can remain for up to 8 hours afterwards..."
Link: Start-Up & Break-In

W/ only ~ 30 min run time on my engine, white smoke is still to be expected. Immediately feeling better. So, I presume that assembly lube has vacated the combustion chamber, but is still in the mid-pipe & exhaust, which would explain why I initially saw no smoke, but smoking once the mid-pipe and exhaust heated up. Conversely, an internal coolant leak would emit white smoke immediately and consistently. K, cool.

So, why is she overheating? I theorized here that putzing around my subdivision at 15-20 mph was too slow to achieve effective cooling. I'd need to test at > 40mph. So, I push start her again and drive to a local main road. OEM coolant gauge comes right up to normal operating temp. While I'm waiting for my thermostat to open and my Prosport gauge to read correctly, I pull up my OBDII reader app on my phone to read the actual OEM coolant temp. Soon after...my thermostat opens and my Prosport temp gauge comes up to temp. I'm glancing between them both and discover at that speed & ambient temp, my Prosport gauge consistently reads ~12F +/- higher than my OEM. Aha moment... I realize that b/c of sensor positioning...my Prosport reads coolant temps exiting the engine, while my OEM gauge reads coolant temp entering the engine. So, my Prosport 210F threshold alarm is actually alarming when the coolant entering the engine is ~ 198F +/-. :dunce: :yelrotflm So, I raise my alarm preset to 220F.

By now she's driving nicely... no white smoke, coolant temps are stable at ~180-185F ...w/no CELs. I'm finally able to relax..."a bit", and ...enjoy the drive. :cool:

Drove ~100 mi. total predominantly on a 5 mi loop requiring regular decels., downshifts to 1st, u-turns, & a moderate acceleration running thru the gears back up to ~45 mph. Over the course of the day I could feel engine smoothness, compression, and acceleration out of u-turns increasing.

Currently, she idles at ~925rpm +/- , but won't quite start on her own yet.









strokercharged95gt 02-11-2019 01:23 PM

I have always kept all my compression readings from when the engine was assembled to thousands of miles out.

I just pull a spark plug from each (i do Leading), pull the fuel pump fuse, and check maximum compression in each chamber while listening to the pulses in the other chamber. Its not the proper way to do it, but its better than nothing. Make sure your battery is charged, throttle is open, and engine warm if you can. Depending on many factors, both my chambers fall in the 90-100 psi range which is okay considering I rebuilt a junkyard motor with old housings, plates, and rotors. It also gives me some background readings to compare to in the event if I think I may have hurt the motor.

Given that the MSP motor is 10:1 compression, I would be worried if either chamber was below 100 psi after a few hundred miles. You should be able the start the car by now unless your battery/starter are weak. Good luck.

jcbrx8 02-11-2019 04:15 PM


Originally Posted by strokercharged95gt (Post 4880862)
I have always kept all my compression readings from when the engine was assembled to thousands of miles out.

I just pull a spark plug from each (i do Leading), pull the fuel pump fuse, and check maximum compression in each chamber while listening to the pulses in the other chamber. Its not the proper way to do it, but its better than nothing. Make sure your battery is charged, throttle is open, and engine warm if you can. Depending on many factors, both my chambers fall in the 90-100 psi range which is okay considering I rebuilt a junkyard motor with old housings, plates, and rotors. It also gives me some background readings to compare to in the event if I think I may have hurt the motor.

Given that the MSP motor is 10:1 compression, I would be worried if either chamber was below 100 psi after a few hundred miles. You should be able the start the car by now unless your battery/starter are weak. Good luck.

Stroker, Yeah, was just IM'ing w/ Brettus about comp testing...to get a base line. From what I've read...compression is changing on a rebuild, depending on components changed, for up to 1200 mi. +/- So, at this point... I'm hoping she'll get to starting cold & hot via starter....and I'll plan to perform my baseline comp test at ~1000 mi. +/-. But I will work out doing the testing myself so I can check regularly as you've done.

Do you use a tester similar to:

https://autosupplies.co/products/compression-tester-kit?CAWELAID=120005270000089336&gclid=Cj0KCQiA14Tj BRD_ARIsAOCmO9a5tl5yVHTQijvWI1evue8wWtE031dGgzjhO6 A2tIw-YPMbrZ3M4yIaAsRQEALw_wcB

rotarenvy 02-12-2019 12:31 AM

Google instructables and rotary compression tester and you can build a diy compression tester for about $50 that will test individual pulses.

jcbrx8 02-14-2019 09:25 PM

Break-in Progress Update:
For Valentines Day she showed me some love: started via starter for the first time. Moving in the right direction. :ylsuper:

I've decided to go w/ the below break-in process:
- < 100 mi, < 4500rpm (oil changed)
- <160 mi, <5000 rpm
- < 220 mi, <5500 rpm
- <280 mi, <6000 rpm *current mileage
- < 340 mi, <6500 rpm
- <400 mi, <7000 rpm
- < 460 mi, <7500 rpm
- <520 mi, <8000 rpm
- < 580 mi, <8500 rpm (oil change)

Engine break-in impressions to date:
  • The idle note sounds a hair deeper & louder w/ a hint of "wobble" which I believe are a result of the exhaust port work.
  • I'm running a 4# spring w/ my EBC off
  • Driving style is reasonably aggressive w/in the break-in rpm range. No WOT.
  • She's no CELs, and idles ~925rpm.
  • "Feels" a little less responsive down low, ~1k-2k rpm, which I suspect is the result of the street porting. :dunno: We'll see...hoping to experience the opposite in the upper rpm range,>6k & up. :fingersx:
  • Pulls firmly at ~ 65% throttle from 3 - 6k (my current rpm limit). :)
Looking forward to seeing the response as I move above 6k rpm, start tipping in more throttle, and finally start increasing and shaping boost onset via EBC.

strokercharged95gt 02-15-2019 06:25 AM

Great news. You should also be keeping note of your engine vacuum at idle as it also gives you a bit more information on how well everything is sealing.

jcbrx8 02-15-2019 09:01 AM


Originally Posted by strokercharged95gt (Post 4881127)
Great news. You should also be keeping note of your engine vacuum at idle as it also gives you a bit more information on how well everything is sealing.

Stroker - Thanks, will do. I presume the stronger the vacuum the better. What range should I look for, i.e. what's healthy?

jcbrx8 02-15-2019 09:39 AM

Q

Originally Posted by jcbrx8 (Post 4874290)
Hopefully w/ no or minimal damage to housings and plates :fingersx: this is a good opportunity to learn and sufficiently "harden" the engine to handle the power the "Rock's cooking" :cool: Ideally, I intend to rebuild this engine w/ all new seals, a street port, dowells, a stud kit, and likely softer apex seals. THEN, FINALLY get my ex mani sealed. :yelrotflm We'll see how it goes... more to come...


Originally Posted by jcbrx8 (Post 4874290)

Who knows what tomorrow holds..., but at this point pleased with progress toward my objectives back in Nov. '18.
- engine rebuilt w/all new seals
- street exhaust ported
- full length doweled
- precision studded
- OEM apex seals
- ex-manifold FINALLY sealed
- have learned MUCH


All-in cost of engine rebuild to date:
-
$925: Atkins closing kit (w/all seals & springs)
- $475: Turblown stud kit
- $440: 2x new "used" housings from Goopy
-
$129: Pineapple solid dowel kit
- $125: Pineapple HD water seals
- $115: Mazdatrix porting templates
- $70: New turbo thermal cover
- $2,279: TOTAL

Note: Plus ~$400: Shop tools (crane, engine stand, dremel tool, etc.)

:xyxwave: Continued thanks to the entire community, but special mention to Brettus, Stroker, & RotarymachineRx!

strokercharged95gt 02-15-2019 10:06 AM


Originally Posted by jcbrx8 (Post 4881137)
Stroker - Thanks, will do. I presume greater vacuum is better. What range should I look for, i.e. what's healthy?

It all depends on engine speed, porting, and engine health (good compression).

I would say anything above 17 inches of mercury (In HG) is good for you at this time. MSPs don't have overlap so it should be relatively high. You would be doing it more to just track the change. Someone may know better.

When I was REW street-ported I would get 15-17 at 900-1000 idle, which isn't great. When I chipped an apex seal, my car idled at like 10 in HG (lost compression in 2 chambers on the front rotor).

When I fired up my bridgeport I originally had 10-12 in HG at 1,500 idle speed, now its 13-14 in HG at 1,500 idle speed. So over the past thousand or so miles the motor makes better vacuum, which should relate primarily to compression numbers since my porting/engine speed hasn't changed.

I always keep an eye on vacuum, it'll be the first thing that drops if you hurt the motor.

jcbrx8 02-15-2019 11:36 AM

Growling a bit before this mornings run... :cool:


jcbrx8 02-15-2019 01:09 PM


Originally Posted by strokercharged95gt (Post 4881142)
It all depends on engine speed, porting, and engine health (good compression).

I would say anything above 17 inches of mercury (In HG) is good for you at this time. MSPs don't have overlap so it should be relatively high. You would be doing it more to just track the change. Someone may know better.

When I was REW street-ported I would get 15-17 at 900-1000 idle, which isn't great. When I chipped an apex seal, my car idled at like 10 in HG (lost compression in 2 chambers on the front rotor).

When I fired up my bridgeport I originally had 10-12 in HG at 1,500 idle speed, now its 13-14 in HG at 1,500 idle speed. So over the past thousand or so miles the motor makes better vacuum, which should relate primarily to compression numbers since my porting/engine speed hasn't changed.

I always keep an eye on vacuum, it'll be the first thing that drops if you hurt the motor.

Stroker, Good info. Just checked... she idles at ~14-15 inHG @ ~925 rpm. I'll periodically keep an eye & track. Thanks.

jcbrx8 02-19-2019 01:21 AM

[QUOTE=jcbrx8;4880771...
- I've a small coolant leak somewhere beneath my radiator feed or return that I'll have to chase down and resolve.
- No oil leaking anywhere. :fingersx:[/QUOTE]

Sorted my coolant leak. After checking all hoses, which are new, I still had a persistent pesky leak over the last few days. Pulled & pressure tested the rad. tonight. Yep... leaks at corners of both end tanks of my dual pass rad. Smh. Swapped in my spare Koyorad. All good.

Currently at ~500 mi break_in miles. Feel the need for a road trip... ;)


jcbrx8 02-20-2019 06:10 AM

She's nearing the end of my defined break-in period and running well. ;)

Normal running vitals:
- IATs: ~ 10F above ambient
- Coolant temp: 180s
- Oil temp: 170s
- No CELs
- No leaks (coolant, oil)

Replaced coolant, now that leak is repaired, and performed my ~500 mi. oil change today. Have a short road trip planned at the end of the week to stretch her legs a bit. It'll also be a good opportunity to assess fuel economy since the porting & rebuild.

jcbrx8 02-22-2019 01:30 PM

Break-in process update:

Investigated break-in processes and discovered they were … all over the map regarding philosophy, rpm restrictions, & increment ranges, and overall break-in miles. All that aside from any good qualitative discussion I could find re: the break-in process of a rebuild w/ used components. :confused: So, I adopted what I considered to be a moderate process having tried to understand the underlying thinking of the varying processes.

My process:
- < 100 mi, < 4500rpm (oil & filter changed)
- <160 mi, <5000 rpm
- < 220 mi, <5500 rpm
- <280 mi, <6000 rpm *current mileage
- < 340 mi, <6500 rpm
- <400 mi, <7000 rpm
- < 460 mi, <7000 rpm
- <520 mi, <7200rpm
- < 580 mi, <7200rpm (oil & filter changed)
*Note: Revised upper mile rpm restrictions…just because. So, still no WOT, no redline.

After initial starting, and temp issues discussed in earlier posts…as expected I observed …especially early on, but throughout… steady moderate improvement in idle, smoothness, and response under increasingly firm accelerations. I’m seeing reasonably good idle now (hard to compare b/c I expect it w/b “different” d/t porting), and ~ 280 mi mark she began reliably starting cold. :) Other vitals are as listed in the above post.

Upon completing my defined break-in period where I’d been on a 1.5# WG spring w/ EBC off, I installed a 6# spring in my WG. It became obvious pretty quickly that wasn’t a good idea :nono:: rougher running, shifted to a deeper “labored” note, unresponsive acceleration, etc. It appeared too heavy a load …especially w/ my turbo spooling earlier. More on that. :) So, back to the house reduced to 4.5# spring w/ EBC off and she’s happy. Engine “note” is normalized, moderate accelerations are responsive. She’s starting cold & hot now. Having experienced this…plan now is to keep this configuration for an extended period, e.g. up to ~2,500 miles.

As mentioned...definitely seeing improved turbo response, haven't quantified it via M/E logs as yet…, but likely at the cost of some fuel economy. More to come on quantifying both of those.

Brettus 02-22-2019 02:06 PM

Rougher running is more likely to be running rich than anything else.

jcbrx8 02-22-2019 02:30 PM


Originally Posted by Brettus (Post 4881684)
I've learned to always compare before and after logs before getting excited about improvements. Rougher running is more likely to be running rich than anything else.

Understood, and agreed. I've been working out a suitable configuration to move forward, and having horrible weather...hard rain everyday, etc. Hoping to get better weather and opportunity to grab some moderate acceleration logs. Hopefully, it is running rich... so it c/b leaned out a bit and recover some fuel economy. :lol:

strokercharged95gt 02-22-2019 02:31 PM

What kind of plugs are you running in that motor? After I completed my first build about 5 years I put brand new $40 NGK plugs in the motor for the break in. They weren't that cold either (9 trailing and 7 leading). After a few hundred miles my car would break up pretty bad if I boosted over 5 psi. After checking everything twice, I decided the plugs were the only thing that were left. Turns out the brand new plugs were fouled, which is very common during the break-in process. The theory is lower compression, lower combustion pressure, and less heat, which tends to never get the plug hot enough to burn off the deposits. I put some $2.99 Autolites in there and the car woke up. Moral of the story, check yo plugs....

RotaryMachineRx 02-22-2019 04:08 PM

I also had spark plug issues when I initially upped by boost pressure from 6psi to 9psi after installing my EBC. Felt like the car would stumble/misfire at certain RPMs with a full load on. Went through a lot of analysis always leading to a dead end until I swapped to these plugs on Brett's recommendation. One log/tune later Brett had me running right as rain. Beware they are pricey though.

Spark Plug - Racing for NGK R6725-10.5 - Racing Beat

jcbrx8 02-22-2019 04:13 PM


Originally Posted by strokercharged95gt (Post 4881689)
What kind of plugs are you running in that motor? After I completed my first build about 5 years I put brand new $40 NGK plugs in the motor for the break in. They weren't that cold either (9 trailing and 7 leading). After a few hundred miles my car would break up pretty bad if I boosted over 5 psi. After checking everything twice, I decided the plugs were the only thing that were left. Turns out the brand new plugs were fouled, which is very common during the break-in process. The theory is lower compression, lower combustion pressure, and less heat, which tends to never get the plug hot enough to burn off the deposits. I put some $2.99 Autolites in there and the car woke up. Moral of the story, check yo plugs....

I've NGK R6725 10.5 plugs installed w/ an extra washer at the trailing positions. Regardless, point taken. :icon_tup: Will do. Thx.

RotaryMachineRx 02-22-2019 04:17 PM

Haha, I guess my comment is moot. If the spark plugs look fine when you check them my guess would be running too rich with the extra load on your current tune.

Brettus 02-22-2019 04:44 PM

I wouldn't run 10.5s in leading ... 9s ideally ...possibly 10s max.

strokercharged95gt 02-22-2019 08:52 PM

I was able to run 9s (leading/trailing) up to about 20 psi started getting knock, moved to 10's (leading/trailing) above 20 psi and knock went away.

I just started running 11s in the trailing position because the plug was light tan color and maybe a tad too hot. Probably would have not been an issue to stay with the 10s in the trailing position, but since my plugs are $2.99 each its good insurance. I change plugs like every 30-90 days so its not a big deal.

So I agree with Brett, 10.5 leading is very cold to be running in the leading position at very conservative driving conditions. Its just begging to foul. I bet you could go with 9s and stay with 9s even with a decent amount of boost. They would probably outlast those 10.5s by a factor of 10 or more.

jcbrx8 02-26-2019 09:38 PM


Originally Posted by Brettus (Post 4881697)
I wouldn't run 10.5s in leading ... 9s ideally ...possibly 10s max.


Originally Posted by strokercharged95gt (Post 4881712)
...So I agree with Brett, 10.5 leading is very cold to be running in the leading position at very conservative driving conditions. Its just begging to foul. I bet you could go with 9s and stay with 9s even with a decent amount of boost. They would probably outlast those 10.5s by a factor of 10 or more.

Thanks, guys. I swapped in 4x BUR9EQs today. We'll see how they do. She's currently just shy of 1000 break-in mi.

Some of the removed R6725 105s did show signs of being too cool, e.g. tan color, carbon/oil build-up.

edit: Pic of R6725 10.5 plugs removed.

https://cimg0.ibsrv.net/gimg/www.rx8...c22aee978f.jpg

jcbrx8 02-27-2019 02:00 PM

Quick feedback:
I'd been experiencing some repeatable engine "stumbling / hesitation" only in the rpm range consistent w/ the onset of boost since my rebuild. I was unsure of it's root cause, e.g. rebuild components, assembly, normal break-in, etc. Determined that if not resolved during the break-in (which is what I expected) I'd trouble shoot & resolve it. I never considered the plugs (R6725 105s) b/c they're the same as I ran prior to the re-build. However, after swapping plugs, 4x R6725 105s for 4x BUR9EQs, during today's drive under similar driving circumstances and style; I experienced no stumbling / hesitation at any point. Smooth as butter again. :)

I think I may h/b on the ragged heat range edge before my rebuild, but not experiencing any issues. But m/h sufficiently increased flow d/t the exhaust porting and finally sealing my ex-mani.; that I was experiencing the fouling / spark blow-out issue now . :dunno:

I'll continue to monitor as I increase rpm and load thru break-in.

strokercharged95gt 02-27-2019 02:46 PM

Those spark plugs look nasty for only 1000 miles. I have had issues with plugs that look half that bad.

Glad you got it all sorted out.

RotaryMachineRx 02-27-2019 04:19 PM


Originally Posted by jcbrx8 (Post 4882006)
Quick feedback:
I'd been experiencing some repeatable engine "stumbling / hesitation" only in the rpm range consistent w/ the onset of boost since my rebuild. I was unsure of it's root cause, e.g. rebuild components, assembly, normal break-in, etc. Determined that if not resolved during the break-in (which is what I expected) I'd trouble shoot & resolve it. I never considered the plugs (R6725 105s) b/c they're the same as I ran prior to the re-build. However, after swapping plugs, 4x R6725 105s for 4x BU9EQs, during today's drive under similar driving circumstances and style; I experienced no stumbling / hesitation at any point. Smooth as butter again. :)

I think I may h/b on the ragged heat range edge before my rebuild, but not experiencing any issues. But m/h sufficiently increased flow d/t the exhaust porting and finally sealing my ex-mani.; that I was experiencing the fouling / spark blow-out issue now . :dunno:

I'll continue to monitor as I increase rpm and load thru break-in.

I had this exact same issue after installing my EBC and upping my boost; except I was the opposite (stumbled/hesitated on the BU9's but the R6725's resolved the issue). Was happening just as the turbo was reaching full spool (peak engine load) and only when the EBC was on. Would get a half second of stumble/hesitation then it would pull strong all the way to redline. Found that it was not related to RPM but rather to peak load.

When I take my car out of winter storage I'm going to pull the plugs to examine and maybe try the BU9EQ's (much less costly plug). My theory is that because I am pushing 9psi on the stock GReddy I am essentially pushing it to it's max meaning charge air is hotter and the cooler plugs help to counter this.

The next logical step for me is to try and get some analytical data on whether the car performs better with more boost and cooler plugs or slightly less boost and hotter plugs.

jcbrx8 02-27-2019 04:30 PM


Originally Posted by RotaryMachineRx (Post 4882024)
I had this exact same issue after installing my EBC and upping my boost; except I was the opposite (stumbled on the BU9's but the R6725's resolved the issue). Was happening just as the turbo was reaching full spool and only when the EBC was on (aka higher boost/higher engine load).

When I take my car out of winter storage I'm going to pull the plugs to examine and maybe try the BU9EQ's again to see if I can replicate.

hmm...I wonder how the balance of our set-ups m/h contributed, e.g. turbine / compressor size, manifold design, piping dia., IC, etc. all which would impact flow & heat. :dunno: Hurts my brain to consider. :yelrotflm

Perhaps some of the SMEs will chime in...

jcbrx8 02-28-2019 11:12 AM

Well, ...during my drive last night... i experienced significant rough running & stumbling. Grabbed the below screenshot of CEL codes. Did the brake stomp reset this morning followed by a short drive, but still not right.

P2070 is d/t a failing SSV valve bump switch (but SSV is working), but the P0335, P0172, & P2097 are new.... Will do some t-shooting today... beginning w/ inspecting the Eccentric shaft sensor, connector and wiring.

https://cimg2.ibsrv.net/gimg/www.rx8...4967cb5b66.png

jcbrx8 03-01-2019 05:09 PM

Walked thru the DTC P0335 t-shooting process. My e-shaft pos. sensor is / was clean and registers 1080 ohms resistance. No opens or shorts to ground or power found on A or B sensor terminals, PCM connector wires and pins look fine. :icon_tup:

Reassembled everything and whala... the worst kind of fix IMO - having no idea what resolved it; but the CEL is gone and she's purring like a cat. I'll take it... :rolleyes:, but don't trust it. :suspect:

Just returned from ~ 40 mi drive. Idle & smoothness are fine and the CEL has not returned. :fingersx: On w/ it...

edit: the P0335 DTC for reference: http://www.rx8ownersclub.co.uk/faq/m...200300W05.html

TomD_Cincy 03-02-2019 06:10 AM


Originally Posted by jcbrx8 (Post 4882177)
Walked thru the DTC P0335 t-shooting process. My e-shaft pos. sensor is / was clean and registers 1080 ohms resistance. No opens or shorts to ground or power found on A or B sensor terminals, PCM connector wires and pins look fine. :icon_tup:

Reassembled everything and whala... the worst kind of fix IMO - having no idea what resolved it; but the CEL is gone and she's purring like a cat. I'll take it... :rolleyes:, but don't trust it. :suspect:

Just returned from ~ 40 mi drive. Idle & smoothness are fine and the CEL has not returned. :fingersx: On w/ it...

edit: the P0335 DTC for reference: DTC P0335



Ahh, the intermittent electrical gremlin. Those are always so much fun to track down.

Brettus 03-02-2019 11:24 AM

It seems to me that these cars offer up phantom faults on a regular basis . I often have to just shake my head and put this kind of fault behind me ...never having found the problem (if there even was one).

swoope 03-02-2019 11:27 PM

i blame lucas.

beers :beer:

jcbrx8 03-03-2019 11:23 AM


Originally Posted by TomD_Cincy (Post 4882196)
Ahh, the intermittent electrical gremlin. Those are always so much fun to track down.


Originally Posted by Brettus (Post 4882205)
It seems to me that these cars offer up phantom faults on a regular basis . I often have to just shake my head and put this kind of fault behind me ...never having found the problem (if there even was one).


Originally Posted by swoope (Post 4882250)
i blame lucas. beers :beer:

Glad its resolved, and hope it doesn't reappear. :fingersx:

Shudder to think what the dealership w/h charged to t-shoot & resolve:... new ECU, harness, e-shaft sensor..."cha-ching, ching, ching...." Smh


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