redursidae

Ben! Thanks for the words dude. I had a blast hanging out with you too! La Junta is the most fun track I've never been to .

Fireindc

iTrader: (13)

Bwahahahahaha! BenR lives!

redursidae

Apologies for the lack of updates. After spending the better part of a month working on the car I needed a break.

A few things have happened:

1. Traded @Fireindc the old BP-4W for a set of 949 15x9 6ULs which I'm super excited to try next year with some 225 tires. These fit over the LBBK like a glove.









2. Decided to install a new to me Roadstersport 3 muffler. It sounds nice at idle and cruise, but unfortunately I think it's a bit too loud for my taste at full tilt. I can still hear ITB noises with the open air filter, but not with the airbox, and that's a bummer. I want to try using the baffle insert before I throw in the towel, and will grab some sound clips later too. The bigger hole around the tip is because the previous owner cut the bumper to fit the cartoonish tip. Post install, the VE table needed a bit more fuel at full throttle which was interesting.







3. Installed longer trumpets to see how it would change the feel of the car, and they seem to be a success. The aluminum stacks are 35mm tall, while these are 50mm. The BP-4W ran 60mm stacks, but with the airbox's internal filter those didn't fit anymore. I must say that the engine feels more linear and less sluggish under 3800RPM! The VE table also seems to agree with my butt-dyno, needing a 5-7% increase at part and full throttle under 4k RPM, and 2% more at full throttle over 4k RPM. I think the exhaust might be the cause for the high-rpm increase in VE. Does that sound right to the hive-mind?


VE Table at the moment. Not fully finished yet but really close


No finishing done on these. Printer in Prusament Carbonfiber Polycarbonate

After printing these I realized that a bigger bellmouth looks cooler, so I'll redesign them at some point. and if someone is interested in printing the old style themselves, here you go! https://www.thingiverse.com/thing:6649878

4. Before embarking to FMSC I mentioned that I thought the engine had a vacuum leak because the idle valve was closing but RPMs stayed high. Well, no vacuum leak to report. The issue seems to be a combination of the 36-2 trigger and the lightweight flywheel/clutch setup. This combination makes the RPMs jittery and caused the idle control to be hyperactive. By increasing the RPM deadtime, dampening the integral response, and allowing idle ignition to do most of the work it seems the idle is happy. It sometimes droops on return to idle at hot IATs, but not bad. I may need to add a 3D table to increase idle duty for high IATs but we'll see in the upcoming weeks.

I promised to talk about the EVAP more, but the truth is that it has been a pain. I've gotten it to a point where it doesn't affect drivability and appears to relive pressure, but because ITBs are so sensitive at low throttle openings/lower RPM, the damn thing goes super rich and I feel uncomfortable removing so much fuel with the 4D table. I imagine PWMing the solenoid would help, but I can't be bothered anymore and just want to drive the car. Sometime soon, or in winter, I'll gut the EVAP system and vent it all as you all have probably been thinking to tell me haha. However, information out there has been confusing regarding correct venting in NBs, so if someone has a straight answer to the correct way of removing all EVAP and venting to atmosphere, I will greatly appreciate it

This is the tune side of the setup at the moment:



The idea with this has been to let the engine warmup, start a counter when it is "cruising" (in vacuum, RPM > 2500, not in overrun and with a bit of throttle applied), then activate the purge and pull fuel with the 4D table. I had a fun time getting the numbers close enough, and while doing so the cancel condition of Lambda being 10% too lean or too rich allowed me to get to FM and back without drivability issues. Link ECU can also check for "shorts" in an AUX output, so if the purge valve is unplugged or dies, it shows as "fault" and the conditions won't activate.

On to other datapoints, the BP-6D has been kicking butt. The only issue is an oil leak from the intake cam seal, which I replaced during the swap. Aside from that, coolant temps are rock solid, oil temps are normal (YAY), and oil pressure is fantastic. While on the stand, the 6D got a Boundary oil pump and an oil baffle from 949 Racing. These two things seem to be keeping the oil pressure stable at the track, which was not always the case with the stock BP-4W. Here is what I mean:


BP-4W under heavy breaking and turning. Lowest point is around 14psi. This also happened on a spirited drive.


BP-6D under heavy breaking. The lowest point is around 41psi.

So I'm stoked with how well it seems to be going so far. The oil leak is annoying, but meh. It'll get fixed.

I plan to attend the next ABQ Superlap event and really want to see how the extra power feels. I'm also interested in trying an autocross event sometime this year and an HPDE with South West Motorsports.

Until then Scooter shall go to car meets, cars and coffee and mountain drives. Here are some pics of our local car meet this past weekend:

Z_WAAAAAZ

Nice update, man! Glad to hear just about everything is going well with the new motor! That's sick you and Nate were able to barter for the engine and wheels. I suspect you'll be amped on the 225s on 15x9s. Curious what plans @Fireindc has for that motor though...

I agree with you on the exhaust front, not being able to hear your ITB induction noise is a dealbreaker haha.

Those oil pressure drops are mad! I didn't realize a non-baffled oil pan would result in pressure drops like that.

Car's looking good, man. Looking forward to hearing/seeing more about it.

redursidae

Thanks bro! I haven’t forgotten about your tail housings by the way. Gotta go pick them up from the shop and will have those sent your way soon.

I have heard often now that 225 would be faster, so I have high expectations. Nate said he is planning to build a forged motor for ol-da-boost.

The pressure drops were wild! Of course I don’t know whether this the case for all BPs, but I’ve read around here that there are drops. Clearly not an issue? You don’t hear of these guys throwing rods or starving of oil often. I did see it in the low single digits a few times when the oil level was getting low, and set the oil pressure safety accordingly. Kind of like a “hey dummy, you didn’t check the oil the last 80 miles….braaaap, fuel cut”

SimBa

One strategy I came across for RPM droop when returning to idle is to set the IACV to idle a bit above your target and use advance to pull the idle down to the target RPM. If you fiddle with the idle advance activation delay/settings a bit you can get a pretty smooth transition.

Not sure if that'll help, but I thought it made sense when I first heard it and have been keeping that in mind during my tuning. Something you might keep in mind.

redursidae

Thanks for that! Yep, that is what I do. The IACV duty is set 1-2% higher across the board, plus a little dashpot adder on return. The idle ignition loop is left to do the majority of the control. So far it is really good with the deadtime and base duty cycle increased a tad

Z_WAAAAAZ

Ah yes! No sweat, I'll take the housings back whenever you get a chance, but no biggie. I put both my dead 6 speeds up for sale but for some reason there hasn't been much interest in a pair of halfway-torn-apart transmissions

You'll be amped on the 225s for sure. My first track day on 225s after coming off of 205s, I thought I was gonna tip out of my seat lol. Very perceivable difference right off the bat (as expected I guess).

Roda

That's some pretty interesting info. AiM allows logging of info imported from the ECU over CAN, so oil pressure from the ECU can be plotted with lateral and longitudinal G from the AiM logger to get some actual numbers under quantifiable conditions. Gives me some more good ideas for after action data gazing.

redursidae

HA! That's exciting. I do wonder if it'll make me slower on the straights, but time will tell.

It was eye opening, but I doubt you'll find the same in the K motor. Those oil pumps are quite trick! But I'm interested to know your findings. Just FYI that your ECU also has a G sensor built in. You'll need to calibrate it, but it's there.

redursidae

Yesterday was ABQ Super Lap Round 4! For once I didn't have to do an oil change pre and post trackday, with no refilling either. Feels good. I also spent the week getting psyched with GLTC with the builds around here and also Kutil's Civic. That thing is sick!

It was a hot day, with ambient temps around ~100F, maybe a bit higher during the time attack. All through the sessions the car had some serious understeer, but almost everyone else was experiencing the same. I also think something is wrong with my front sway bar, but I'll investigate later. I got some coaching by 3 young drivers that race Formula 2000 and Spec Miata which certainly helped remove some of the doubts I've had regarding lines and braking zones. Now I need to practice their teachings. One of them, Isaac, is one of those that runs 1:32.xx during Spec races. Wild and impressive.



Fastest lap was a 1:35.888, 3 tenths off my PB with one major mistake and other smaller ones. Really happy with that outcome. And that was also good for 1st place in my class! All the temperatures were perfect, with a max of 97C (206F) for coolant and oil, and 51C (123F) for intake temps while moving (before it would be around 74C on a day like that!).



One of my cooling fans started rattling a bit, and the oil leak seems to be getting worse. I'll have to dig into that soon. Otherwise, I want to get the car on a dyno to maximize the VVT and ignition timing. Virtual dyno claims it should be around 135whp adjusted for altitude, which sounds somewhat believable?

I also put a baffle in the Roadstersport 3 muffler, and quite like it. It balances the sound much better and still does a pop here and there. I've also purchased a header heat shield to attempt to insulate the engine bay some. I'm just realizing that some gold foil might also help to insulate the backplate of the ITBs a bit. Anyways, it seems only minor details are left, except for the 6-speed swap. Scooter keeps on scooting!

Roda

Congrats! That's an awesome result.

FWIW, my VVT BP with flattop, skunk2 TB and RB header put 135 to the wheels, so you're in the ballpark.

redursidae

Thank you!

And that's good to know. Assuming it is somewhat correct, it puts it around 20whp more than the BP-4W, which virtual dynoed at ~115whp.

I hope your weekend went well. Did you get to look at the oil pressure data?

Gee Emm

Good result! Always nice to pick up the odd bit of silverware, it may be just a trinket for the shelf but it is something of a measure of progress, a mechanical and personal achievement. Having basically retired from (semi-)serious competition, I still look at mine and smile - I did that!!

Stock

I buy it. I had dyno'd 137whp on my fist VVT engine, swapped in another yonke-yard VVT and used the same tune and ran a ~1:34.7 up there with more tire (albeit cycled out) and aero.

Congrats on the win!

Fireindc

iTrader: (13)

Nice work Ricardo! You earned the P1, keep it up and you'll be dipping into 34's in no time.

Z_WAAAAAZ

Heck yeah dude, congrats on the W! I know it was expected but that's a killer drop in IATs vs your previous setup.

Glad the car's kicking *** after all the recent work you've put into it.

SimBa

Good work out there! Always nice to have the data confirm that a modification made a difference.

redursidae

Thank you! It is nice to get a piece of metal for the efforts haha. My first win, hopefully not last.

Thank you on both accounts! Good to know the engine is in the ballpark. I haven't forgotten about getting in touch whenever I go to ASR. The local group here is planning an ASR trip latter in the year and I'll reach out when we have a date.

WootWoot! It may have been different if the Brian's had been there, but I'll take it! I hope to hit a 34 sometime this year if I can string it all together.

Thank you both! And yes, it feels very nice to make progress. I miss having the intake noise from the open filter, but I know the engine is happier with lower temps the airbox provides.