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I understand this one.
This is something you see and interact with everytime you get in the car.
It always bugged me that my TII door panels that I converted to wind-up for weight savings didnt quite match the rest of the interior.
Because the car was (lightest) S4 TII with Blue interior and the only manual door panels I could find were S5 Blue which looked a "little* brighter Blue and less Gray Blue.
Same as the non-sunroof headliner when I made that weight reduction. Could only find S5 non sunroof headliner.
When I put my momo in my BLUE TII 2001 I was looking for a way to incorporate the stock emblem I took off the old wheel, bit "never got around to it."
Ditto that, lol. Mine is sitting in a box of stuff to eventually do. Right next to the cigarette lighter I forgot to install and haven't for several years...
i was yesterday years old when i learned how a boost gauge works...
btw 80mm IS REALLY BIG
you can see in the pic, there is/was a foam ring in there, and it had come apart. i carefully uncrimped the glass and 2 screws and it was apart
it turns out that the gauge is a bent tube and when you blow it, it gets straighter...
i'm a plank. basically rebuilt the turbo again, back to stock because the stock turbo was really fun. the stock turbo hit 6psi at 2400rpm, and 13psi by 3200, which is quite a ride, and it happens where you drive the car anyways, its a hoot.
the V trim in a stock housing was much more even, it would hold boost up to redline, but for some reason it would only boost ~6psi, and then it was super laggy too, full boost by like 3500?
i put the stock turbo back on, expecting the carnival ride power curve, but instead i get 6psi by 2800rpm, and it just holds that to ~6500. its pretty fun but i was starting to wonder if i am the only person on the planet that cannot get an S4 turbo to boost creep, wtf!
but i'm a plank you see. the FD has an idle air bleed, there is a hose that comes from the lower intake and goes to the y pipe, and it looks weird, because it goes from the intake to the intake, wtf. what it does though is since the Y pipe is not under intake vacuum it feeds air to the primary injectors, and it made a pretty big difference in how my car runs. mileage went from 12 to 17+. the only problem is that since i don't have a y pipe i teed it into the only place i have that is before the throttle, the boost solenoid hose.
so what i think happens is that the boost solenoid can do whatever it wants, but can't bleed off anything because there is a hose from the intake teed into it....
i bought a check valve, so hopefully i can feed the injectors air, but let the solenoid do its thing. if that doesn't work, i'll have to add a fitting somewhere....
so i've just been tuning it. for some reason i'm the only person in the world that has functioning boost control on an S4 turbo, but its been interesting to tune it at 0.5kg/cm and then move it up. its got, like every FD a very definite power peak right at 6500rpm, but this is about 1000rpm higher than i'm used too with an FC engine, it also doesn't drop off after the peak like the FC does, which is neat i guess. at 0.5 the boost arrives around 2800, and it'll keep it all the way to 6500. running 0.6 its starting to have the typical FC bell shape boost curve, it gets 0.6 between 3500-5000rpm. intake temps have been really low, which they should be, i've got the biggest IC you can fit in the car without a sawzall, intake temps are around 35c on a 20c day, which makes the numbers look really good.
i really need to plumb in an exhaust back pressure gauge/sensor, i think that is where the numbers are pointing me....
this is all great but, my tuning problem is kind of a funny one. i only use the car to go get coffee on the weekends, basically. its a short drive to warm the thing up, it gets parked, wait 30-45 minutes, and then a hot restart. for some reason (giant intercooler) my car has a big difference between hot and cold. the PFC bas map idle warmed up is like 11.2:1 AFR, which is stupid rich, but on a hot start it'll be like 12.2:1 or something, which is still rich, but it runs fine. the FC Tweak and i have been fighting over the idle AFR (i think i sometimes hit the idle cells driving...), and i'm surprised at how lean this car can run without misfires, 12.8 is fine, warm. however on a hot start (coolant temp will be like 75c and air temp is like 45c) 12.8 becomes like 14.2 or something which is not fine, so there is ~30 seconds or so of stalling and bad running before the air intake temp sensor is actually reading actual air temps, and this is with the fast reacting one.
the compromise has been to just make the idle richer, 12.5 warm is better, and once the map is tuned i think i need to add some fuel in the 50c intake air temp part. the funny part is, if you just drove the thing like a normal car it runs great
the PFC bas map idle warmed up is like 11.2:1 AFR, which is stupid rich, but on a hot start it'll be like 12.2:1 or something, which is still rich, but it runs fine. the FC Tweak and i have been fighting over the idle AFR (i think i sometimes hit the idle cells driving...), and i'm surprised at how lean this car can run without misfires, 12.8 is fine, warm. however on a hot start (coolant temp will be like 75c and air temp is like 45c) 12.8 becomes like 14.2 or something which is not fine, so there is ~30 seconds or so of stalling and bad running before the air intake temp sensor is actually reading actual air temps, and this is with the fast reacting one.
That is EXACTLY like what's happening to me on my MS3X. I have everything else tuned well so it runs perfectly. But for some reason on a hot start after a few minutes heat soaking, I get these lean spikes at idle for about 15-30 seconds.
I think it's due to the IAT sensor not reacting quick enough. I need to play with the afterstart enrichment or something to try and tune it out, but since the car works fine under all other conditions I haven't gotten around to it yet.
I wish mine would idle leaner though. Even at 900rpm idle, it gets choppy when leaner than about 12.8. I'm wondering if modern injectors (or even lower mileage ones since mine have almost 400,000km) would help with that.
it does take about ~30 seconds of running before the air temp sensor is reading right, i have logs
once my map is tuned though i will probably add some fuel in the range where the AIT is when i do hot start it, that should help too
i just want to let the autotune get to ~90% before i start changing the air temp map. currently i'm at 66%, and in my day i could have weaseled that into a B+, no problem
Are y'all using open- or closed-element IAT sensors? Closed element sensors react more slowly to changes so that could be causing the discrepancies you're seeing.
Are y'all using open- or closed-element IAT sensors? Closed element sensors react more slowly to changes so that could be causing the discrepancies you're seeing.
i started with the closed FD sensor in the FD location, which basically reads intake manifold temp. then i moved the FD sensor to the elbow, which helped.
then i put the fast reacting sensor in the elbow, and its ~30 seconds of running before its "right" it is way better.
Are y'all using open- or closed-element IAT sensors? Closed element sensors react more slowly to changes so that could be causing the discrepancies you're seeing.
I'm using the stock S4 NA sensor. Which I believe is open-element. It reacts pretty quickly on my logs when driving (if I snap the throttle for example, it starts to cool down quickly), but then I haven't tried logging one of these hot starts yet. I intend to move to the GM open-element sometime in the near future anyways.
in tuning by plonkers, i richened up the cells next to the idle cell and the hot start thing got way better. i have my idle set to 800rpm, and there is an 800rpm cell, which is nice, but idle is ~480mmhg, which is between cells, so it interpolates. also i think when i'm tuning i have actually hit the cell it uses for idle while i'm driving, which is partly why i get mixed results with the autotune. anyways, changing the cells surrounding the idle cells has helped, its like the slope was too steep, or not steep enough
its not 100% there yet, but its better
the plonking part. i went down the turbo rabbit hole, i wanted to know how to read a turbine map, and it turns out you can't, you need to take pressure measurements and EGT and do the math. i built a spreadsheet that does the maths, its interesting if you play around with the numbers it sort of tells you what is wrong with the combination (everything from air cleaner to tail pipe). a few other people have used the ACV and EGR ports to get pre-turbo back pressure, and that sounded like the place to start.
so i bought a Banzai block off plate, and happily its way thickkk, and ends up like this:
which is great, however test has revealed that if you block the EGR port, then the EGR port is blocked.
soooooooo
i decided to try post-turbo pressure, hoping that wasn't also blocked off (at K2RD we made a turbo block off...)
this worked! post turbo back pressure was, 12psi at 7000rpm..... its amazing it ran....
so i pulled the cat, and hollowed it out, and was rewarded with 7psi at 7000rpm.
it boosts a lot faster, boost is up, it hits 10psi in the midrange, and at 6800rpm its 8.4psi....
next step is obviously a bigger cat back. so i've been shopping for a catalytic converter.
i want the SARD sports converter, but it costs money, and isn't legal here, so its hard to justify spending the money. although since its not legal here its reasonably priced
I found downpipe makes the bigges difference in spool 9n my TII.
Probably because the exhaust has the highest temperature and turbulence right out of the turbo.
My Racing Beat 3" downpipe to Racing Beat midpipe had 3 cheated radius cuts if I remember correctly.
Putting in the mandrel bent 3.5" downpipe/midpipe from the JIC Spec 90 even with the 3" Racing Beat cat back as a restriction to prevent boost creep livened the low rpm spool and response substantially.
If you drill and tap the lower intake manifild where it covers the port air passage in the center side housing you can get cooled off preturbo exhaust pressure through the port air passages in the exhaust sleeves.
I found downpipe makes the bigges difference in spool 9n my TII.
Probably because the exhaust has the highest temperature and turbulence right out of the turbo.
My Racing Beat 3" downpipe to Racing Beat midpipe had 3 cheated radius cuts if I remember correctly.
Putting in the mandrel bent 3.5" downpipe/midpipe from the JIC Spec 90 even with the 3" Racing Beat cat back as a restriction to prevent boost creep livened the low rpm spool and response substantially.
yeah i've already got one!
:monty python gif:
ive got some JDM 70mm pipe, which is nice because it actually bolts up to the main cat, because this car needs to pass smog, although i may have to open a smog shop to do it...
so one of the Magazine cars i like is also blue
and its one of the few cars that actually has an actual REW swap in it. its running a hybrid S5 turbo and 90mm exhaust.
the theory is that the stock turbo needs a bigger intercooler and bigger exhaust to compensate for it being kind of small.
its kind of a floor sweepings car like mine, its a Cosmo engine, with FD junk on it, in an FC. stock injectors, ROM tuned ecu and hybrid turbo
they claim 340ps (likely flywheel) at 1 bar.
so yeah a 90mm system crossed my mind, although i'd need to diy it at this point. if anyone actually made one, it would be a billion dollars to ship it
Ive always liked the look of the 13B-RE throttle body elbow on the 13B-REW intake like that RE-A car has.
and it fits better than the REW with FD elbow. it is actually probably easier to swap the Cosmo engine in the car (or just run the Cosmo center iron), and put the FD stuff on it, than it is to go full REW
08-28-22, 03:49 PM
