Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   DIY Turbo Discussion (https://www.miataturbo.net/diy-turbo-discussion-14/)
-   -   Kraken 6758 build (https://www.miataturbo.net/diy-turbo-discussion-14/kraken-6758-build-104542/)

Spaceman Spiff 06-07-2021 11:29 AM

Is there an option to limit slew rate in MS/TS?

Dr.Sep 06-08-2021 01:54 PM


Originally Posted by Spaceman Spiff (Post 1601749)
Is there an option to limit slew rate in MS/TS?

not specifically, but my understanding is that D and sensitivity slider can counteract it... messed around for a couple more hours last night and seem to have it a LOT closer now, was still getting a weird fluctuation right around 8psi so I turned off boost control entirely and did a few pulls... turns out wastegate is set at 160kpa, not 198 as I had thought, so I am wondering if this has something to do with that weirdness. Rebinned my bias table with 160 as a starter and will try that as soon as possible; forecast looks dismal the next few days so might have to wait until the weekend.

Figuring out closed-loop boost sucks, hopefully its worth it.

Having some warm idle issues too where it doesnt seem to catch the RPM dip if I put the clutch in too soon or let it return to idle from a rev in neutral, which is getting annoying and wasnt present when it was cooler. Once a project, always a project I guess

fwman1 06-09-2021 06:56 PM

DNMakinson pretty much sorted CLBC on 1.4 and higher. The secret sauce was to set the bias table much lower than the figure your pulls would indicate. Why it works better like this is a mystery to me but it works.
It is almost like it needs to be fed a larger error to predict where you need to end up. The speed of change in boost also impacts being able to plateau just at the right time. I expect that you are really building boost quickly. Version 1.5+ has the ability to log P I D in boost (among other). It is not real time, but it does really help in seeing which element needs to move which way and how your changes take effect. Search the megasquirt forum and you'll probably find the thread. The good stuff is near the end.

Dr.Sep 06-11-2021 07:44 AM


Originally Posted by fwman1 (Post 1601991)
DNMakinson pretty much sorted CLBC on 1.4 and higher. The secret sauce was to set the bias table much lower than the figure your pulls would indicate. Why it works better like this is a mystery to me but it works.
It is almost like it needs to be fed a larger error to predict where you need to end up. The speed of change in boost also impacts being able to plateau just at the right time. I expect that you are really building boost quickly. Version 1.5+ has the ability to log P I D in boost (among other). It is not real time, but it does really help in seeing which element needs to move which way and how your changes take effect. Search the megasquirt forum and you'll probably find the thread. The good stuff is near the end.

So this does seem to be the key, lowered my boost duty table from ~68 peak to 55 and lowered the rest proportionally and am getting much better results, even in just basic mode I am getting a LOT closer without those weird fluctuations; hit overboost at first and lowered the sensitivity and its much better. Drove last night in around 82 ambient air temp and was on target, took it to work this morning and it was about 55 ambient and hit my targets without hitting overboost so I am pretty happy with that -- before a 25deg air swing would either slap me into overboost or I would only be seeing ~15-16psi instead of 18 (I know, not a huge deal... but when I want it all, I want it all; I paid for 18psi and im going to use it)

Dr.Sep 07-13-2021 07:09 PM

It’s a been a bit, time for an update

closed loop EBC seems to be working well — again the key with MS3 seems to be to undershoot your duty targets

1300 miles so far, couple little things came up (listed the car for sale for 8 full hours out of frustration at one point lol)

An oil leak developed right at the corner of the CAS cap and valve cover, so got a new OEM mazda valve cover gasket and used even more of the black rtv and that seems to be good now

but then I realized I was still losing oil… way more than I should have been like 1/2 qt per 300-400 miles and a little smoke on startup and revs. Talked to a friend who had encountered something similar with a broken PCV system and he suggested basically just venting both sides of the valve cover (both to a can with a breather really)

so I figured I’d give it a shot, started it up and saw this
https://cimg5.ibsrv.net/gimg/www.mia...20b9ca909f.png
Puffing out the breather, hmmm — blowby from bad rings or an okay amount of blowby from rings with larger gaps to builders specifications running turbo

So I pulled the plugs, each looked pretty much the same — a little dark from running rich, but all equally so none stood out

So did a compression test with the cheap-o tester I had and gotCyl4 - 90/170

Cyl3 - 90/160

Cyl2 - 90/165

Cyl1 - 90/165

Well within range of each other, and the car runs well

okay so probably not rings (this is when I removed the ad haha)

did a couple more tests, PCV valve is definitely bad — so ordered a GTX one, and added a second catch can on the pre-turbo side of the system. I am also just going to run the intake side as a VTA after the catch can and not connected to the intake vacuum port at all and will keep an eye on my oil level… the puff at startup has gone away so I’m hopeful.
Put a new set of plugs in while I was at it too

https://cimg9.ibsrv.net/gimg/www.mia...5393e001c.jpeg
Intake catch can VTA on the firewall, mini catch can on pre-turbo side mounted to top of radiator for now

I will make those a little prettier, but for now I’m just hoping it works. Otherwise, car is running great


Dr.Sep 07-22-2021 06:14 PM

not super scientific, I know, but some small changes *feel* better!

https://cimg9.ibsrv.net/gimg/www.mia...68fab9f3d.jpeg
High boost canister, straight wastegate
https://cimg3.ibsrv.net/gimg/www.mia...639f1a5be.jpeg
Old log of medium canister (8.8psi max straight wastegate)
https://cimg6.ibsrv.net/gimg/www.mia...d08cbeb2e.jpeg
PTP blanket and fresh FM air filter
https://cimg7.ibsrv.net/gimg/www.mia...c6f3e0ae3.jpeg
With blanket, high boost canister, and fresh filter

Boost really does seem to come on sooner, I attribute this more to having an appropriate spring weight for the wastegate, but did notice temps were cooler with the blanket (oil and water)

still burning a little oil, thinking it’s valve stem seals on cyl2 possibly but going to run it until winter and then tear down. Smoke and oil loss is minimal after fixing pcv, car runs strong so sending it!

andyfloyd 07-22-2021 09:24 PM

FWIW I only see smoke out the breather on a dyno run at full throttle. I dont ever see anything at idle or cruise speeds/low boost part throttle. Your compression seems good so I would just send it and enjoy it. I too am ---- and OCD and let that kinda stuff bother me so I know how you feel.

curly 07-22-2021 10:30 PM

You can send in oil samples to Blackstone. So far I’ve pulled my motor twice because of them. Might be cheaper to ignore their results I guess.

andyfloyd 07-23-2021 01:04 PM


Originally Posted by curly (Post 1605020)
You can send in oil samples to Blackstone. So far I’ve pulled my motor twice because of them. Might be cheaper to ignore their results I guess.

When you pulled the motor did you find issues that the oil analysis found?

Dr.Sep 07-24-2021 11:41 AM

^^ I am curious about this too -- what would their analysis be able to tell me? I took a look around their website, peeked at the sample report, but can you tell me a little more about what it told you about the engines you pulled? $30 is entirely reasonable at this point if it can help me narrow down why I am still puffing some smoke after idle/vacuum when I get hard on the gas... turbo seals because of inadequate drain or excessive crank pressure (or is that fine with my ring gap) or both, valve stem seals, or is there an issue with ring gap (I feel like I'm going in circles) so if an analysis could actually help narrow that down I am in

curly 07-25-2021 09:49 PM

It's best if you send in a sample every oil change, or when you're concerned about something. If your bearing materials like lead, copper, and tin are extremely high like mine, it's usually obvious you've got issues with them.

I had bearing noise and sent off a sample, although already pulled the engine and inspected bearings before I received the results. Did it again to verify the levels were going down, but they had instead gone up. Kept an eye on knock levels for ~500 miles, sent in another sample, levels were down but not amazing. Inspected the bearings again, and they were starting to show wear again. I'm done with race bearings, trying OE rod/mains now with a fresh non-ground crank.


Dr.Sep 12-13-2021 09:21 AM

Some updates

car made it through the Rochester car season, never got around to e85 this year but did take some andyfloyd sauce (octane boost) and was seeing 22psi, but don't love the guesstimate of 1 octane bottle per tank. After talking with my builder and fixing a non-functioning PCV valve my oil consumption issue is under control. They hooked ya boy up with big ol ring gaps, so I do have to keep an eye on oil level but it isnt coming out the tailpipe any more so I am good with that. The (working) GTX valve helped considerably, I found that it just seems to work better with my system to keep the PCV with a catch can, and a second catch can off the other side drawing vac from pre turbo -- car is happier that way rather than venting both to atmosphere through catch cans.
Car is currently on the lift for the winter with a few things on the list:
  • 3.6 Torsen is a must refreshed with new bushings, will be selling the 35k mile 4.1 torsen that is in there (axle nuts are being difficult) but no rush because I haven't sourced a 3.6 yet
  • Supermiata radiator to fix the coolant reroute routing, it sneaks under the intake right now and I want to move that
  • Skunk2 throttle body round 2, we shall see...
  • Intercooler piping, Napp Motorsports owes me a little work for storing a car through the winter and wants to make my charge pipes nice (no complaints there)
  • Couple little wiring things, redoing low/high boost switch to just be a simple on/off switch so that I don't have to power cycle to go from wastegate to more-than-wastegate, and clutch switch for 2-step
  • Bash bar? Took of my bumper and noticed my drivers side crash bar looks like it kissed something before my ownership so just want to go through and make sure all that is good
Still would like to see what it will do on e85, my tuner seems to think my 1000cc's and DW300 won't actually net me much going to e85 and that I would need much larger to keep up with the flow of e85 but Greg Peters seemed to be able to take his further -- who knows

The Australian 12-14-2021 04:20 AM

Mine is making 460+ with ID1050x and a w460 on e85 and a 6758.

Dr.Sep 12-19-2021 08:03 PM

https://cimg6.ibsrv.net/gimg/www.mia...794d0e9f0.jpeg
Cat and goodies

also snagged a 3.6 from a forum member, waiting for it to ship out 👌🏼

Lokiel 12-20-2021 01:01 AM

^
Wrapped perfectly!

Janky 12-20-2021 10:44 AM

I'd be happy to buy your 4.1 torsen if you could hold it for me. I'm usually in Rochester every month or so

Dr.Sep 12-20-2021 11:30 AM

Sure, DM me and we can work on a price etc -- not looking to get rich, but offsetting my 3.6 cost would be awesome

95RedM 12-22-2021 12:47 AM


Originally Posted by The Australian (Post 1614046)
Mine is making 460+ with ID1050x and a w460 on e85 and a 6758.

what fuel pressure you running ?

95RedM 12-22-2021 12:52 AM


Originally Posted by Dr.Sep (Post 1613995)
Some updates

car made it through the Rochester car season, never got around to e85 this year but did take some andyfloyd sauce (octane boost) and was seeing 22psi, but don't love the guesstimate of 1 octane bottle per tank. After talking with my builder and fixing a non-functioning PCV valve my oil consumption issue is under control. They hooked ya boy up with big ol ring gaps, so I do have to keep an eye on oil level but it isnt coming out the tailpipe any more so I am good with that. The (working) GTX valve helped considerably, I found that it just seems to work better with my system to keep the PCV with a catch can, and a second catch can off the other side drawing vac from pre turbo -- car is happier that way rather than venting both to atmosphere through catch cans.
Car is currently on the lift for the winter with a few things on the list:
  • 3.6 Torsen is a must refreshed with new bushings, will be selling the 35k mile 4.1 torsen that is in there (axle nuts are being difficult) but no rush because I haven't sourced a 3.6 yet
  • Supermiata radiator to fix the coolant reroute routing, it sneaks under the intake right now and I want to move that
  • Skunk2 throttle body round 2, we shall see...
  • Intercooler piping, Napp Motorsports owes me a little work for storing a car through the winter and wants to make my charge pipes nice (no complaints there)
  • Couple little wiring things, redoing low/high boost switch to just be a simple on/off switch so that I don't have to power cycle to go from wastegate to more-than-wastegate, and clutch switch for 2-step
  • Bash bar? Took of my bumper and noticed my drivers side crash bar looks like it kissed something before my ownership so just want to go through and make sure all that is good
Still would like to see what it will do on e85, my tuner seems to think my 1000cc's and DW300 won't actually net me much going to e85 and that I would need much larger to keep up with the flow of e85 but Greg Peters seemed to be able to take his further -- who knows

you can get 400whp on stock fuel pressure with those 1000cc injectors. Maybe a tad under. Bump it up to 60psi and you’ll hit 450. That’s so crazy that your car likes that PCV setup, my car HATED that PCV setup, and even at this point with both sides vented it still burns a bit of oil, but not as bad as before and I’ve got my leaks under control. When I hooked the hotside to the turbo intake it would almost fill that catch can within like 3 days. It was insane. I hope you get e85 worked out, this is why I taught myself how to tune so I could make whatever changes I want and didn’t have to be held up by a tuner.

Dr.Sep 01-02-2022 05:03 PM

Just some progress updates made over break, back to work tomorrow though


https://cimg6.ibsrv.net/gimg/www.mia...8406893a5.jpeg
Room for activities
https://cimg9.ibsrv.net/gimg/www.mia...887491880.jpeg
Got the 4.1 out, still waiting for the 3.6 supposed to be here tomorrow but the tracking doesn’t seem to be updating so I really don’t know. Got new competition bushings coming and the diff braces to be welded to whatever housing is nicer

https://cimg1.ibsrv.net/gimg/www.mia...6646dfa90.jpeg
Got the new skunk2 TB on there. Went together MUCH better than the eBay one I junked. Don’t expect big gains here, but I like nice things 🤷🏽‍♂️

Also wired up launch off the top clutch switch (will run spark and fuel cut)

and rewired the High/Low boost switch to be a simple on/off with the wastegate. Tried to have it boost table-switch last year to have actual low and high boost, but didn’t realize you have to “power cycle for changes to take effect” so this is on-the-fly and will run wastegate 16psi most of the time

Really hoping my 3.6 comes soon (or comes at all?????)


All times are GMT -4. The time now is 09:56 AM.


© 2024 MH Sub I, LLC dba Internet Brands