Well, there is no issue w/ the dash cover hard base itself. The issue lies in the black vinyl covering ...on the base cracking. That's why I'm gong to investigate some other suitable covering to apply over the base that allows airbag deployment, is consistent w/ the cabin surfaces, and won't crack. I believe finding a suitable material w/b the most difficult challenge. May enlist my wife's assistance w/ that. :icon_tup: Attaching it via adhesive or other means s/b simple. At least so says he who hasn't attempted it yet...:yelrotflm

Or....................... don't leave it in the sun all day.

That shouldn't be an issue...as my car h/b garaged at home and work virtually it's entire history.

What do you guys think about these leading plugs I pulled (1L & 2L)?


https://cimg7.ibsrv.net/gimg/www.rx8...6ccd21fa4f.jpg.

Dang, those sure are fouled. I’d imagine the trailing being better but probably not ideal. Which plugs you going with? NGK iridium? Or the race ones?

The colour isn't too bad but the amount of crud for the mileage is a lot . Kinda says to me the the heat range is fine for the high boost runs you are doing but the fouling is from the sedate driving in between..... So colder would help with that.

Spark Plug Config.
 

I'm thinking that my AFRs being rich d/t my contaminated MAF didn't help matters either.

Moving forward I'll run:
- L: 7420-9s (aka NGK 6448)
- T: 7420-10s (aka NGK 5501)

Update:

Installed my NGK 7420-9 plugs and did a few pulls. The below is at ~13 psi: 345 HP / 260 ftlbs. She's a blast to drive. I've a number of To Dos to complete before spring, and will work to sustain torque profile across the rpm range..., but otherwise very pleased w/ the project. Initial objectives h/b met. :)

Team - Are you not entertained? Are you not entertained? ;)
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You Tube

https://cimg9.ibsrv.net/gimg/www.rx8...0ced785960.png
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If the torque kept rising after peak torque then it wouldn't be peak torque :dunno:

Touche' :yelrotflm

Power level is ideal for my objectives, i.e. high enough to h/b worth the investment, ...low enough to hopefully sustain reasonable reliability for a Renesis. :fingersx:

While some of the HP & Trq slope decline post 5k rpm is likely d/t a boost leak and my dynoing process..., I've no doubt there is decline, which I w/b working to minimize. I'm hoping to find untapped power via:
- eliminating boost leak
- EBC optimizing
- freer flowing intake & exhaust
- perhaps tuning (I'll consult w/ /Brett)
- potentially EBC capable of provisioning boost per rpm range

Thoughts? Any other ideas?

To get your boost to hold better it could be as simple as taking the line that goes to the solenoid from just before the throttle instead of from the turbo. What that does is supply air at a slightly lower pressure to the actuator. Be careful of how you route it and ensure it's secure as you don't want that line coming off !
That should give you maybe another 10-15whp at peak rpm.
Past that it's about how efficient your system is ....... I recommend setting up a line to measure EMAP which will tell you exactly that. You will be able to monitor improvements as you make them.
Your exhaust would be the first place to start ...IMO.

While I think of it ...we need to lower your rev cut if you are going to keep pushing limits like this :).

Thanks, Brett.

My solenoid signal line is plumbed to the last charge section (just prior to throttle body). :yesnod:

I agree that an EMAP w/b a useful tool in measuring & monitoring system back-pressure. But atm I believe I m/b able to achieve my goals by simply enacting obvious measures to reduce opposing intake &/or exhaust pressures, e.g. air filter (next week), ...later perhaps a higher flow catback. If that doesn't get me to my objectives... then I'll install the EMAP. :icon_tup:

oh ... didn't realise you had already done that ...lol

:icon_tup: Absolutely, ...don't mind sacrificing a few rpm at the top of my declining torque curve at all. :yelrotflm

it should be flat, like you’re thought process except for torque that’s a good thing :)

So it’s not a curve either Einstein and it wouldn’t make the engine anymore prone to failure once past the peak. Go look at that 719 rwhp graph on RX7Club, that’s so beautiful; flat 500 ft-lbs torque for about 3000 rpm range.

sad sad pandas is crying ...

I was curious if the torque decline I'm seeing is EBC settings...or hardware related. So, reduced boost a bit, and experimenting w/ EBC settings to see if I can reduce torque decline. Initial results are positive... as compared to the v-dyno in post #538.


https://cimg2.ibsrv.net/gimg/www.rx8...28eed37d43.png

The issue is you have a turbo capable of 500 whp. It was never my intention to give you grief or goad you into blowing a motor. I had perceived that you chose that turbo for it’s intended purpose, but now realize that’s not the case.

At this power level a BW S257 SX-E or even the S251 would be suitable for your current power level with a notable response benefit. Kind of where you are now is an oversized turbo operating at an undersized output level. It’s just finally starting to get spooled up and then being neutered with a low boost setting. That’s not a criticism; just an honest assessment of what’s going on with it. It could likely be handled better with a boost by rpm setting strategy by incrementally bumping up boost to ramp it off flat and hold it out to redline. I don’t know if that’s possible without changing the pcm, which then you’ll lose emissions compliance capability.

I realize and believe that now. And my response c/h been better. Water under the bridge. All good. :icon_tup:

You're right: I did not realize the potential of the 6266 turbo. Not that I'm displeased w/it, but had I known...I w/h selected a smaller turbo w/ better response for my objectives. That said I'd always planned to increase boost some, but only after transitioning to E30.

Having transitioned to E30 I've increased boost a bit. But thinking thru the torque decline post peak,... that I'd seen at every boost level...on a turbo capable of blowing more air than I'm pushing thru it didn't make sense, and caused me to suspect it was EBC tuning vs. hardware related. :rolleyes: I had provisioned my EBC actively utilizing WARNING & LIMIT to constrain max boost...RATHER than tuning max boost using SET, GAIN, and SET GAIN only. Then using WARNING and LIMIT essentially as a safety net, which should rarely be engaged except in the event of a hardware failure. As seen above...early indications reducing the % LIMIT support my suspicion that the LIMIT features constraint was having the unintended effect on torque as well.

edit: I've considered a progressive controller, but believe I m/b able to achieve my goals w/my existing EBC using better tuning philosophy.

It's been raining lately and I've some loose ends to sort..., but I'll continue retuning my EBC in this way and am interested to see the upper rpm range of the natural HP/torque curves of my 6266 with the LIMITING feature constraint fully lifted. :yesnod:

Ok, well looking forward to seeing you get some positive results. :biggthump

Thinking about the sizing of the 6266 for my set-up a bit more...I believe it is, albeit in the upper range, a good fit for my goals: a reliable DD at ~340HP / 250Trq . :) 2nd gear is spooled by ~3800, and 3rd by ~ 4100 rpm, which means during normal driving I'm typically under full torque, BUT on it's rising edge. So, my system sacrifices the immediate torque / responsiveness of a smaller turbo,...but not by much :nono: ...as even slight tip-in brings full torque nearly instantly. I actually reduced throttle sensitivity to better govern torque onset through this range. And this set-up operates the turbo in its higher efficiency islands, reducing heat and wear, yet doesn't run out of puff ...when pushed.

So, I've no experience DD'ing a car w/ turbo fully spooled during normal driving, but w/b interested to hear perspectives from those who do. I'm sure I'm overlooking some benefits of that system set-up.

IMV for all right reasons, e.g. comparing and contrasting across systems, we can become so focused on system metrics that we lose sight of the "point": the desired driving experience, While biased...I'm actually quite pleased w/ mine. :ylsuper:

edit: She's still teaching me how best to tune and drive her. :yesnod:

To what exactly are you disagreeing? :dunno:

First, my turbo current max output is ~52 lb/min. That places me on the ~62% island of the BW S257SX-E w/ little room for growth. :nono:

Using the T66 compressor map, the closest approximation I could find for the 6266 given Precision notoriously holds their maps close to the vest, 52lb/min places it at ~ 74%, w/ growth potential, should i desire, out to ~60 lb/min while remaining at ~70% efficiency. So, admittedly, what is sacrificed in responsiveness is gained in efficient growth potential.

https://cimg3.ibsrv.net/gimg/www.rx8...6666692dbb.png

I am not claiming the 6266 is squarely in my sweet spot...responsiveness vs. top end. I have said I w/h selected a slightly smaller unit. However, my larger point was that it "all" has to do w/ a) individual objectives and b) resulting "driving experience"... to which IMV the 6266, though in the "upper (size) range", fulfills mine.

Aah, you're basing your calculations on the v-dynos *I've posted.* :)

I'm pulling g/sec (lb/min) directly from M/E data logs. :yesnod:

IMV for all right reasons, e.g. comparing and contrasting across systems, we can become so focused on system metrics that we lose sight of the "point": the desired driving experience, While biased...I'm actually quite pleased w/ mine. https://www.rx8club.com/images/smilies/ylsuper.gif

Curtis : a better comparison to your turbo would be a Garrett GTX3582 as Precision and Garrett use very similar design and the T66 is very old tech plus I think that's a bigger compressor .... 66mm inducer wheras yours is a 62mm.

Team : Your matchbot examples are showing a horizontal line for the compressor output which suggests to me that you haven't factored in the increase system backpressures from exhaust,intercooler,intake etc with increased flow. Have a read of the Matchbot notes!
The difference between a 1.00 and a 0.83 isn't going to be anywhere remotely close to 100whp. More like 15-20 at peak power.

Thanks, Brett.

Below is the GTX3582 map.

• ~74% efficiency @ 50 lb/ min :icon_tup:
• supporting growth to upper 50s lb/min airflow still at 70% efficiency. :icon_tup:

I'll take it.

https://cimg8.ibsrv.net/gimg/www.rx8...b5ff23732d.png

That's the gtx gen 11 map .... yours will be closer to the std gtx map .... not far from what you see there though.

I got the 100whp from your comment above.

As far as filling in Matchbot goes ...I have an actual engine with measured parameters to compare actual vs theoretical so have a pretty good handle on how the numbers fall into place .

I still have some issues to sort, a boost leak being one, but w/ rain stopped and dry pavement... I did a 3rd gear pull today @ ~12 psi ensuring my EBC parameters were set to ensure that WARNING / LIMIT would not be engaged.

This should be a better approximation of the torque curve of my setup. Significant improvement: torque climbs smoothly until 6763 rpm. The implication of this result is encouraging...when applied to my previous 13 psi v-dyno in post #538:
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• Nov. 14 pull @ ~ 13 psi (Post #538): 260 ftlb @ 4850 rpm,...235 ftlbs @ 6800 rpm (delta: -25 ftlbs)
• Nov. 25 pull @ ~12 psi: ....................230 ftlb @ 4850 rpm,...246 ftlbs @ 6800 rpm. (delta: +16 ftlbs) :ylsuper:

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https://cimg9.ibsrv.net/gimg/www.rx8...a9089f74e2.png

Taking advantage of some Thanksgiving holiday time off to make progress on my winter 8 To Do list.

- Repaired leak and swapped back in my dual pass rad.
- Fashioned a bead crimping tool...$15.
- Inspected and reformed intake and charge sections, where required.
- Added beads, to supplement the welds, to problematic intake and charge sections

Note: Learned thinner stainless steel clamps are better than the wider t-bolt clamps which disperse clamping force over too great an area for this application.

Next up:
- install mini 8" tall IC.
- install charge & intake sections
- install new LRB aluminum under tray.

https://cimg6.ibsrv.net/gimg/www.rx8...7972295488.jpg
Bead crimping tool
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https://cimg7.ibsrv.net/gimg/www.rx8...c1b2657cff.jpg
compressor inlet section w/ a knarly end and no welds or bead. (before)
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https://cimg9.ibsrv.net/gimg/www.rx8...b944117dff.jpg
Reworked compressor inlet section (after)
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https://cimg1.ibsrv.net/gimg/www.rx8...667ee6aed2.jpg
Problematic throttle body charge section w/ new bead installed to augment the welds.
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https://cimg8.ibsrv.net/gimg/www.rx8...cab34109ef.jpg
Dual pass radiator leaks repaired and reinstalled
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https://cimg0.ibsrv.net/gimg/www.rx8...4ddee35d03.jpg
Mo'-tor mount rubbers swapped: 3 section rubber on the bottom, 2 section rubber on top.
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Team, Thanks.

I'd been experiencing...
- a boost leak delaying spool (oddly intermittently)
- vacuum leak(s) causing leaner than desired afrs...during initial boost rise, then leveling nicely throughout the rest of the rpm range. The higher the boost...the more concerning

So, I'm hoping to optimize the system by ...among other things...better regulating afrs throughout the rpm range, and improving boost threshold and spool. If successful..., achieving previous boost levels won't be an issue. :yesnod:

Agreed...concerning the v-dynos. They are useful *approximations* of power levels, but generating them via M/E is definitely an art, not a science. And some are simply snippets of spirited driving rather than disciplined WOT pulls.

A little progress this evening after work...
- installed charge section from compressor outlet to my new mini IC.
- spent a good deal of time sorting out... and fabricating installation of the new mini IC.
The new IC looks so small compared to my old IC. Hoping it cools as effectively..

Next up:
- Install charge sections into engine bay, and to the throttle body
- Install LRB under tray

Note: Maxi IC m/b for sale once I confirm mini does the job.
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https://cimg8.ibsrv.net/gimg/www.rx8...13b6b4d7b8.jpg
Mock up of mini IC, and comparison of mini vs. maxi IC
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https://cimg8.ibsrv.net/gimg/www.rx8...37afa808d6.jpg
Glad I didn't toss the RX8Performance IC mount. Works well for the shorter IC.
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https://cimg0.ibsrv.net/gimg/www.rx8...a953e59b49.jpg
Mini IC installed...

Further progress update:

Re-installed...
- CAI and MAF sections
- post IC into eng. bay, and to throttle body charge sections
- vac & charge lines ....(jet air, OMP, oil catch, BOV, charge signal line to WG)
- ECT and IAT sensor wires

Note: The fully rolled / beaded section ends gave confidence to install charge sections w/ only shorter couplers w/ no further reinforcement. :fingersx:

Next up:
- install the LRB aluminum under-tray.
- dbl check everything...

https://cimg4.ibsrv.net/gimg/www.rx8...59d9aa19f9.jpg
Bay (left)
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https://cimg1.ibsrv.net/gimg/www.rx8...c8f9587bd0.jpg
bay (front)
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https://cimg2.ibsrv.net/gimg/www.rx8...b6a922dd84.jpg
bay (right)
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https://cimg7.ibsrv.net/gimg/www.rx8...dba54d7fba.jpg
IC - bay, bay - throttle body charge sections, coupler, and new clamps
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Edit:
Team & Brett were correct...after swapping the passenger motor mount larger rubber to the bottom w/ a large washer on top under the brace arm (see post 566 pic), I was able to reinstall the largest under brace w/ no clearance issues. ;)

Plan to install some heat shielding around the motor mount as well. :icon_tup: Edit: Added.

https://cimg4.ibsrv.net/gimg/www.rx8...f03f4d7efb.jpg
Large under brace installed
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https://cimg2.ibsrv.net/gimg/www.rx8...cc9ea26c41.jpg
Heat shielded motor mount

:suspect:

My bad...I'd forgotten...you and Team both provided guidance on this. Edited

Thank you both. :icon_tup:

Yeah, I understood that..., but the large washer's ID is too small, ~0.5", and the mount stud diameter is 1.5". I just bought the largest new washer I could find with ID >~1.5".

Hoping not to have sagging issues down the road with the mount heat shielded. :fingersx:

Just looking at this again ..... I think it will still be hard to seal . You should remove the welds and crimp all the way around. Then smooth the top of the crimped ridge as much as possible so that creates the seal . ATM you have gaps between the crimped parts where air can escape and you rely on the hoseclamp to seal it to the pipe on a section that doesn't line up properly.

If you are having a hard time keeping couplers from bursting, I have found that rubbing the aluminum with a thin layer of hylomar helps. Especially if you twist the coupler back and forth a few times on the pipe until the hylomar tacks up real dry.... Or you could do it the boring professional way :)

You know... I thought about doing that very thing before creating the bead around the welds. :doh:
I'll rework it. Thanks. :icon_tup:

Hmm, interesting....

I've used a small amount of hair spray to install the couplers this time round. I'll try hylomar when I reassemble the charge section to throttle body coupler above. Thanks. :icon_tup:

I've a previous commitment that's going to interrupt progress for a few days...but I'm working on installation of a legit aluminum under tray atm. This puppy w/b tight as a drum. :yesnod:




https://cimg4.ibsrv.net/gimg/www.rx8...fdadc1f03.jpeg
Pre-installation layout...
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https://cimg6.ibsrv.net/gimg/www.rx8...a77f5a082.jpeg
Verticals installed...
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True. I did something similar until now..., but mine was the original under tray and a bit beat up.

Yes, I believe this will seal much better...

https://cimg8.ibsrv.net/gimg/www.rx8...dbeea98997.jpg
Originally beaded only between welds
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https://cimg2.ibsrv.net/gimg/www.rx8...2adb072d7b.jpg
Taped and fully beaded
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https://cimg8.ibsrv.net/gimg/www.rx8...e1a591594e.jpg
JB Weld applied
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https://cimg7.ibsrv.net/gimg/www.rx8...6376e8c478.jpg
....

hmm ...hope that jb weld will hold in there !

Well......me too. Lol. The JB weld specs indicate a tensile strength of ~4000 psi, and withstands ~500 F temps when cured. Additionally, the boost force in the section should force the coupler to wedge the JB weld between the coupler and bead on the aluminum section all around.

Otherwise....
- awaiting delivery of a 90 degree coupler to fit my new IC to exit charge section
- need to customize the aluminum under tray to accommodate my IC inlet and exit charge sections and seal it up
- reinstall the charge to throttle body section and assoc. signal and sensor lines

3" OD. Didn't see your post. Always interested in ideas...

Team - Thanks. That's a good idea. :icon_tup: I did that very thing...i.e. install a 45* elbow on the other end of the same charge section at the FMIC --> eng bay -[coupler]- eng bay --> TB connection ...shown below.

But having fully beaded the section end...I'm going to try the straight coupler...first, and move to an elbow coupler if the connection still doesn't seal.

I've growing confidence that the fully beaded end will seal. To keep this post clean... I'll explain why below.

What Brett said below was a paradigm shift in my thinking regarding "how" to create reliable coupler seals.

My kit came w/ small welds at 3, 6, 9, and 12 o'clock positions, which b/c they did not completely circumference the charge sections caused me to believe these were ONLY for the purpose of creating a mechanical "connection" to keep the section from blowing off under boost, and that the coupler clamping force created the airtight "seal". While this m/b a method of sealing couplers..., I don't believe it's the better method. :nono:

Brett's above comment caused me to consider generating the seal in the same way a cork seals, which relies on a gradually increasing O.D. In this case the more pressure applied..., the tighter the seal.

This is the dynamic I'm trying to create, and am optimistic will work. :fingersx: If it works on this difficult curved section...it w/b effective on ANY charge section...
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https://cimg2.ibsrv.net/gimg/www.rx8...3fc4804b9e.png