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Weekly episode of rookie maneuvers with Zak! Here's the most recent issue I've completely overlooked on my car.
Long story short, I need to do a better job of checking and understanding what my tuner is doing to my car. For a while, I've been wanting to play around with my VVT table/settings just to get some firsthand information on how it affects the running aspects of my engine. I know how it works in theory (advance in the midrange yields more torque, no advance needed closer to redline, etc.) and have seen plenty of VVT tables on here to know roughly how one should look. However, I just wanted to d*ck around with my advance table and see if I could document and perceive the differences with VVT on and off in different scenarios.
TL;DR: I just wanna play around with something new to me in TS.
Well, I pulled up the VVT angle gauge in TS last night and that's where this week's rabbit hole started. VVT angle showed 15* at idle with no advance commanded. That's gotta be wrong... I put 'er into test mode and couldn't get any less than 15* of advance. I knew my cam timing was on the money but did a quick double check to make sure I wasn't being an idiot. Mechanical timing was good. Went into the VVT settings and found the min and max angles changed from where I had originally set them after building the engine the first time. I start to see what's probably going on here. Checked the trigger wheel decoder and the angle offset was set at zero. I.E. not where I had set it to get correct base ignition timing.
When I built and started this motor the first time, I needed a -5.0* offset in TS to get the ignition timing on the money. I know it's not the same as what a lot of people on here are have run, but that's what my engine wanted. Actually, now that I'm thinking about it, I think it might've been because I had the settings on rising edge instead of falling edge. Regardless, when I got the new engine dyno tuned, my tuner said he was going to change the setting to falling edge and set the base timing again. Again, now that I'm thinking of it, I don't remember seeing him take out a timing light.
Long story short, I think my tuner changed my trigger setting to falling edge, zeroed out the trigger offset without actually checking base timing, then proceeded to punch in a baseline set of numbers into my ignition table. I checked the base timing today and found it to be retarded by 5* compared to what TS was reading. I set the trigger offset to -5* and it went back to reading on the money.
Current ignition table attached. I'm sure this table isn't perfect, but the boosted rows seem to be in line with what most people are running on setups similar to mine (91 oct, Kraken manifold, GT2560, 3" exhaust, 1.9L VVT, 8.7:1 comp ratio, etc.) Based on what I found, I was running only 8-10* of ignition timing at 220kpa (my current max boost setting). That's in the ballpark but it seems on the low end of things. Maybe he was trying to punch in safe numbers but make it look like I was running more timing than I actually was? That's stupid but I can't come up with any other reason to tune the whole table with incorrect base timing.
Anyways, I took the thing for a spin at lunch, subtracted 1* of trigger offset at a time and did a handful of pulls without hearing any knock. I stopped at 4* just to be safe and will probably purchase a pair of detcans to confirm there's no pinging going on that I can't currently hear. This weekend, I'm also going to reset my min/max VVT angles so the VVT advance actually works as it should again. Also, I may start asking around about other good tuners in the area for when I do the e85 conversion as well.
Obligatory shot of the car. She definitely picked up some power but I'm gonna have to make sure the timing is safe before beating on it!
I know how it works in theory (advance in the midrange yields more torque, no advance needed closer to redline, etc.) and have seen plenty of VVT tables on here to know roughly how one should look.
Actually you can run MORE timing with rpm climbing. Less timing with higher pressure.
I think you are running a lot of timing and boost for 91oct without meth injection, if your base timing is spot on right now. I would back that down a few °, especially on a track car.
Thanks for the feedback, guys. I know the VVT theory is a little more complicated than I described it. However, I did previously think that advancing the intake cam past peak torque wasn’t supposed to net any gains. I’ll take a look at some other VVT tables on here.
I decided not to pour all the base timing back into it just to err on the safe side. That being said, I would like my actual timing to be consistent with the numbers in TS. I’ll pull 4* of timing in the boosted rows before setting base timing (which was 5 degrees off) correctly.
Curly, can I trouble you for your input on the non-boosted rows as well? Based on your guys’ responses, I’m assuming they’re alright.
Honestly I'm not sure. It's obviously much less important than boosted cells, however it can help with cruise efficiency. My rule of thumb is 28* at 100kpa, and drop 1-2 degrees per psi of boost above that. Logic says you can then increase timing below 100kpa, but what the proper amount is, I'm not sure. I've seen anywhere from mid 30s to mid 40s, I usually don't go over 36ish. I've also seen the highest numbers in the cruise area (3000-4000rpm), or like yours, at the lowest kpa/highest RPM, again, not entirely sure which is correct. I tend to make it highest in the cruise area, then taper off a bit above that.
I can only tell you one thing:
My vacuum cells are really close to yours, maybe 1-2° more retarded. Actually, my whole table is really close, but I run 102 octane race gas all the time and don't track my car.
I target 15.5 in cruise and with the amount of timing we both run, I get phenomenal fuel consumption.
No ping at all
Thanks to both of you guys for the feedback. I’m gonna pull timing from the whole map and just go back to where I started, but with the correct trigger offset so TS reads the actual timing now. My takeaway from all this is that everything was running good before and I shouldn’t be pushing it on a track car running 91oct.
I might’ve gotten a little too gung-ho when I saw the trigger offset was incorrect. Thanks for the sanity check and potentially keeping me from burning a hole in a piston
Thanks to both of you guys for the feedback. I’m gonna pull timing from the whole map and just go back to where I started, but with the correct trigger offset so TS reads the actual timing now. My takeaway from all this is that everything was running good before and I shouldn’t be pushing it on a track car running 91oct.
I might’ve gotten a little too gung-ho when I saw the trigger offset was incorrect. Thanks for the sanity check and potentially keeping me from burning a hole in a piston
That's def the right approach. Seen many people blow engines over the years trying to squeeze out more power with timing (people love big dyno numbers). I'll take 5-10% less power if it means the tune is safe.
One shitty tank will blow **** up the first session you are out.
Maybe add some good octane booster (millers turbo) to be a bit safer, when searching more power
Haha, yeah I'm in the same mindset as both of you guys. I'm not gonna search for more power right now. I just got childishly excited when I saw that my timing was 5* retarded and didn't think that my map looked that far off from other pump gas maps. In my stupid excitement, I also forgot that most pump gas maps here are on 93 octane and not our sh*tty 91 Cali octane.
Next up, 1000cc injectors, E85 sensor wiring and setup, and AN fuel lines. I want more power but honestly feel like I should hit each of our local tracks at least once at my current power level to see what sort of times I can pull. I don't absolutely need more power until GTA Finals next year where I'm hoping to break into the midpack in street class.
Mini update on the suspension setup. I took the car out to a secluded mountain pass north of LA yesterday evening to see how the 14k front springs handled compared to the 10k's. I wish I could say otherwise, but I couldn't notice a substantial difference in how the car handled. Maybe I'm just not super perceptive to the intricacies in my car's setup. Maybe the difference won't be noticable until I'm driving at 100% on the track with them. I'm running the same ride heights as before (4 3/4" pinch weld height front and rear) although I didn't adjust my damping settings yet (assuming I should be running more damping overall in the front now, the BC coilovers have a single adjuster for compression/rebound). The good news is that they don't seem to ride any harsher than the previous springs.
Final thoughts to come after this Friday's track day. I'm actually going to experiment with putting my front sway bar in the stiff setting as well if the car's still exhibiting substantial oversteer.
Haha, yeah I'm in the same mindset as both of you guys. I'm not gonna search for more power right now. I just got childishly excited when I saw that my timing was 5* retarded and didn't think that my map looked that far off from other pump gas maps. In my stupid excitement, I also forgot that most pump gas maps here are on 93 octane and not our sh*tty 91 Cali octane.
Ha totally understandable.. you thought you had free powa untapped. I would've been excited too.
Mini update on the suspension setup. I took the car out to a secluded mountain pass north of LA yesterday evening to see how the 14k front springs handled compared to the 10k's. I wish I could say otherwise, but I couldn't notice a substantial difference in how the car handled. Maybe I'm just not super perceptive to the intricacies in my car's setup. Maybe the difference won't be noticable until I'm driving at 100% on the track with them. I'm running the same ride heights as before (4 3/4" pinch weld height front and rear) although I didn't adjust my damping settings yet (assuming I should be running more damping overall in the front now, the BC coilovers have a single adjuster for compression/rebound). The good news is that they don't seem to ride any harsher than the previous springs.
Id think 10k would be considered stiff at 560 lb/in. I'd guess it might be hard to tell the difference on the street unless you're really pushing things to the limit (which most people don't do). On the other hand I asked a friend of mine who races if he can perceive tiny difference like say 4 psi difference in tire pressure and he says no and believes most people are full of **** who say they can. So don't feel bad.
You’re right, 10k isn’t super soft especially for a street car. However with 200tw 245s, the car generates a decent bit of body roll at the limit haha. Moreover, paired with 8k springs in the rear, the 10k fronts don’t keep much weight off the front and create a decent bit of oversteer at the limit.
You’re completely right though. I’ll rip my car in the canyons but not near as hard as at the track. The difference should be more pronounced there.
I dream of the day I can hop in a car and tell details about the setup like that. Although, like he said, it seems like a lot of people who claim to know what they’re talking about are full of crap haha.
Back when I worked in a bike shop and was racing bikes consistently, I had this buddy who could not be satisfied no matter what he did with his gear/setup. He couldn’t make a jump or drop that day? It was because his shock didn’t have enough air in it. Couldn’t corner well one day? His tire pressures were off. And so on and so forth.
One day he bought a bike and set it up with a 160mm travel fork (a little longer than what most people spec’d on that specific bike). He came over the next day complaining and crying the blues about how the fork caused the bike to climb bad, made flat corners harder, etc. etc. I told him I’d swap the air shaft in the fork to space it down to 150mm and all his problems would go away. I put the bike in the stand in front of him and swapped the 160mm air shaft out with another 160mm. He called me the next day in absolute elation about how the bike handled now and how all of his gripes with it were gone. My buddies and I let him ride it that way for six months without telling him what I actually did to it
One day he bought a bike and set it up with a 160mm fork (a little longer than what most people spec’d on that specific bike). He came over the next day complaining and crying the blues about how the fork caused the bike to climb bad, made flat corners harder, etc. etc. I told him I’d swap the air shaft in the fork to space it down to 150mm and all his problems would go away. I put the bike in the stand in front of him and swapped the 160mm air shaft out with another 160mm. He called me the next day in absolute elation about how the bike handled now and how all of his gripes with it were gone. My buddies and I let him ride it that way for six months without telling him what I actually did to it
As an ex-MTB mechanic this cracked me up. I had a few customers like that as well on the latest greatest carbon 8k+ enduro hardware. Then a few of us shop rats would go ride our AM hardtails on the same trails and hang with them on their hero bikes. That'd usually shut them up.
As for your spring rate changes, I just made almost an identical change last season. Switched from 550/300 to 800/550. On the street it was surprisingly not super different. Even on my dirt road, i mean it was noticeable but not really any more harsh, it just didn't bottom as much.
On the track it was a whole 'nother world. I'd never try to track a high HP on those spring rates again. 550/300 would be perfect for an N/A car on 205's tho.
I put the bike in the stand in front of him and swapped the 160mm air shaft out with another 160mm. He called me the next day in absolute elation about how the bike handled now and how all of his gripes with it were gone. My buddies and I let him ride it that way for six months without telling him what I actually did to it
Lulz, this is hillarious...
My buddies are the exact opposite.
My mate bought a used Last Herb DH 204 v5 this summer and didn't touch a clicker the first time out with it in the bikepark. Told me that thing was super planted and he could rip like hell with it.
Next time I was there with him and checked his setup roughly in the parking lot.
The DHX 5.0 shock had ZERO pressure in the reservoir and rebound was totally ****. The damper even had a dead spot the first few mm of its stroke and was super inconsistend in its damping. Sometimes it kicked, sometimes not, clattering down the hill. I just asked him while laughing how he can ride that thing. He just shrugged his shoulders and said "I just didn't care and had a lot of fun", haha. Legend, still doing all the big jumps with it. I installed a nice Vivid Air and set it up for him, he couldn't believe how great it felt with decent and working suspension
I also ride motocross and people don't even ride their new 10k bikes stock to see how they feel. Instantly "modding" without a base line... I don't understand how so many people are like this and like to burn their hard earned money.
I ride a '08 250 and kick *** with it, if I really want to. Always the driver/rider
Haha, I'm with both of you guys. Mad respect to the dudes out there happily out-ripping people on older/lesser equipment.
SOW recap! On the coattails of our previous setup conversation, the stiffer front springs made a difference... cranking up the damping in the front made a bigger difference.
I got off work early on Thursday, grabbed my rental trailer from Uhaul and proceeded to still get stuck in LA traffic despite leaving before rush hour. The 140 mile drive to Willow Springs took all of five hours. Absolutely lovely.
Slept cozily Friday night in 28-degree weather. Getting up at 6am to meet my friends showing up was tough. So warm under the blankets and so not-warm literally everywhere else. Luckily, the sun came up around 6:30 and brought temps up to a balmy 40* by our first session. Damn, reading all this back, I sound like a weak, bitchy SoCal resident hahaha.
First session the track was still cold and pretty slippery. I haven't run SOW counterclockwise for over a year, much less with anything over 100whp, so I got to work simply familiarizing myself with the track and lines again. There's a line on CCW going through the "bowl" that I always have trouble with, staying as high up/far outside as possible on the banked left corner until the radius decreases sharply at the end. A little too much speed means you're dropping down the embankment on the backside.
I was getting more confident in the line and how my car was running so far when I came out of turn one and hit the gas with no effect. Great, fuel pump ground wire must've pulled itself again, or worse. I coasted into a turnout and began to wait for a tow. Being impatient to begin the diagnosis, I went to cycle the key on and off to listen for the fuel pump. The key only clicked one detent backwards.
I had killed the ignition by hitting the key with my knee. Sure enough, I cranked the motor and it started right up. Crisis averted
Left to right, Turbo 1.9 BP, Built e85 K24 Miata, Kraken low mount/EFR 6758 Miata with 400whp.
I paid close attention to my suspension setup throughout the morning. Even from the first session, I noticed the car was still somewhat easy to oversteer despite upping from 10k's to 14k's in the front. It's worth noting that the average speed at SOW is close to 60mph, not high enough for aero to have a substantial effect in many parts of the track. I had upped the front damping settings from 14 clicks to 17 clicks (out of 30) clockwise, but had made no other changes. After talking to another buddy about it, I figured the rest of the answer was right in front of my face. I cranked the front up to 28 clicks and the rear up to 22. Normally, I advocate for making one adjustment at a time, but whatever. Boom, excessive oversteer basically gone. The car actually had a little less oversteer than I wanted with these settings but I was glad to have found a point where the concern I wanted to change had completely subsided. I'll probably drop the front damping to 24 or 25 for the next track event.
Another fun bit about this track day was that my buddy who put on the event gave me an instructor wristband for the day, allowing me to give and go for ride alongs. I took a few of my buddies out in the car (so satisfying audibly hearing your friends' hootin' and hollerin' while you're wheeling the car around the track). I also rode along with a couple friends and was able to impart what meager knowledge I have to help out their technique/line choice.
There was also a Miata party lap at lunch for promotional photos/videos.
Found this on Saturday morning lol.
I couldn't put a perfect lap together to save my life on Friday, but was able to pull a PB of 1:23.85. Satisfactory, but I know I could easily get into the low-1:23's or 1:22's with a little more time and traffic-less track. I didn't get the line on the bowl down until the second to last session, and pulled my best lap on the final "open" session with the sun in my eyes. Excuses aside, I'm still stoked to have broken into the 1:23s and have something to look forward to for next time.
Next Friday, Buttonwillow CW13 again! All I gotta do this week change the oil, fix a wiring issue that's causing the oil temp gauge to fluctuate wildly, change all four tires, diagnose a minor driveline vibration, do a brake flush, glue the front splitter back together because I banged it on the trailer, and and and and and and...
Looks like it could use some more camber with that outer shoulder wear? Really cool updates, It's always a good feeling to finish up a track day and only have basic maintenance to do before the next one.
Haha, I'm with both of you guys. Mad respect to the dudes out there happily out-ripping people on older/lesser equipment.
Ya ultimately just run whatcha brung and have fun.
SOW recap! On the coattails of our previous setup conversation, the stiffer front springs made a difference... cranking up the damping in the front made a bigger difference.
I paid close attention to my suspension setup throughout the morning. Even from the first session, I noticed the car was still somewhat easy to oversteer despite upping from 10k's to 14k's in the front. It's worth noting that the average speed at SOW is close to 60mph, not high enough for aero to have a substantial effect in many parts of the track. I had upped the front damping settings from 14 clicks to 17 clicks (out of 30) clockwise, but had made no other changes. After talking to another buddy about it, I figured the rest of the answer was right in front of my face. I cranked the front up to 28 clicks and the rear up to 22. Normally, I advocate for making one adjustment at a time, but whatever. Boom, excessive oversteer basically gone. The car actually had a little less oversteer than I wanted with these settings but I was glad to have found a point where the concern I wanted to change had completely subsided. I'll probably drop the front damping to 24 or 25 for the next track event.
Good to hear it worked out. This makes sense on paper as the shocks probably need the rebound dampening cranked up (close) to max since you're running a much higher spring rate on the BC shocks. With those spring rates and aero I'd think you could dial out the oversteer. I tried to lookup some info on the BC's but didn't have any luck. I'm guessing the adjusters adjust both compression and rebound stiffness..? Looks like a fun weekend!
^As he said.. ya looks like you could use a little more negative camber.
The tire wear situation is due to a number of factors. The tires currently on my car were brand new then subjected to two track days in a row on a clockwise course, wearing the left sides of each tire more than the right. I took the two right tires and flipped them on the wheels a few weeks ago so I would wear the less worn edges more while driving them around town until the next track day. Hence why the tire pictured is oriented in the wrong direction. I then forgot that we were running counterclockwise this weekend and never flipped them back, making the worn edge taking the brunt of the wear for three track days in a row haha. I probably could up the camber in the front now though, especially with the 245s and current aero. I'm running 3.3 degrees up front and 2.8 in the back. Tires don't seem to be riding the sidewall at 28psi cold, but I haven't used a pyrometer to measure outer/inner temperatures yet.
Teg: Yeah, the adjusters increase or decrease compression and rebound at the same time. Guess the additional rebound damping works well in conjunction with the increased spring rate up front. Although, on the coattails of my previous posts, I couldn't perceive the front end bouncing around at all before really cranking the damping up haha.
Might swap my 8k rear springs for 10k's on Wednesday if time allows. That's a long shot though, I have so much to do this week before leaving for the track again Thursday lol.
Teg: Yeah, the adjusters increase or decrease compression and rebound at the same time. Guess the additional rebound damping works well in conjunction with the increased spring rate up front. Although, on the coattails of my previous posts, I couldn't perceive the front end bouncing around at all before really cranking the damping up haha.
The difference is very slight/subtle and probably hard to really feel it on the street imo. I crank up the rebound stiffness on my kwv3's for track days and turn them down when on the street. It makes a noticeable improvement on track for sure but on the street it just adds a lot of harshness for little/no benefit (you just don't push the limits on the street really). Another consideration is how rough/bumpy the track is. Here at the local track too much rebound stiffness definitely unsettles the car over rough surfaces compared to a softer shock setting. Sometimes you need to find that balance and the softer setting that allows the tire to maintain contact works better.
That's exactly what I've been noticing with the spring rate/damping changes. The front spring rate increase didn't increase harshness nearly as much as the damping did, and yes, I noticed the bounce from insufficient rebound much less than the harshness from adding compression haha. Luckily, it's still not excessively jarring on the street IMO.
Like you said about finding the sweet spot regarding stiffness/compliance on track, I'm interested to start playing with my settings for different courses. My car's always been soft enough that I haven't had to worry about compliance on any track. Streets of Willow just had a repave recently and is super smooth with no curbs, so the added firmness wasn't any issue last Friday. Buttonwillow, however, has tons of curbs that you need to hit and a couple pretty solid bumps in the track. I'm interested to see if I need to back off on the damping this weekend to keep the car from deflecting on the rougher parts of the track.
To add to this discussion, I swapped in the 10k springs on the rear yesterday. The difference in ride quality was immediately more noticeable to me than the front springs. Interested to see how the setup performs on track. I also increased front camber from 3.3* to 3.6* this morning. I'll play around with the damping settings this weekend and see how she goes.
Ideally, I'd like to tune out most of the oversteer the car exhibits, then put a 1/4" of rake back in the car. I'm currently running 4.75" pinch weld heights all around and previously the car was outrageously oversteery running even 1/4" lower in the front. As I understand it, if I can tune out the excess oversteer and still run 1/4" rake, the steering should gain some responsiveness without wanting to kick the rear end out wildly around every corner...
12-08-2023, 06:54 PM
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So don't feel bad.
