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Thanks Pat, that is pretty much exactly what I need.
It's just shipping it out and the time involved would knock the trackday out the window, but again I really do appreciate the offer there.
I've been in contact with the machine shop and there is maybe a possibility next week, just need to keep the pressure up in the nicest and friendliest way :-) I will put the feelers out at a couple of other shops too.
I've already begun reinforcing the manifold flange and I think its going to work. Ive added extra 5mm plate across the back of the flange in between the ports and tigged the top and bottom, effectively doubling the thickness to about 9-10mm in these weak areas. I will rib the these thicker areas into the ports to triangulate the load paths at the top of the flange. I really don't see it flexing after that. It will be significantly beefier than before I attacked it with my sander. I am also going to rib the lower area of the flange to triangulate at the bottom of the ports to the flange, and this should significantly reduce the amount of pull on the top of the flange the sc can exert also.
I'm being really careful with the extra welding and I haven't pulled it anymore yet. Fingers crossed. With a machined flat surface after all that I think there is a good chance we will be back in business.
This is a snapshot of the boost leak event from the logs. You can see tps and map rise. AFR down around 11.0 as we get into load. MAP peaks at just shy of 200kPa then drops to around 150kPa with TPS still at max (95%). At the same time the MAP drops the AFR increases quickly from 11ish up to around 15.5 then more slowly increases up to 17-18AFR. All with TPS wide open until I realise something is up and come off the throttle, then I give it another little stab but realise something is wrong as I see the boost gauge only make the 6-7psi. Bottom graph is the EGTs as raw ADC. They are increasing slowly through the run, but no sudden jumps, and I checked coolant temps and there wasn't a flicker. Hopefully I've got away with it if I can resolve the issue.
I was thinking about potential causes and I think it must be the flange. If I had popped a seal in the supercharger or chargecooler I would not expect to see the lean event, the ECU would just fuel for the lower MAP and I would just feel a loss in power. I also think I would find a load of oil or coolant in the induction system from when I lifted off and pulled engine fluids in from the other side of the seals, which I haven't. If the bypass hadn't shut properly I would also expect to only see and feel a loss of power due to a lower MAP, not a lean event.. If a vacuum hose had come off, say the hose to the fuel regulator the fuelling in cruise and idle would be all over the place, which it wasn't. Seals on the injectors are all good and they are bolted tightly in place. No sensors popped out. Anything fuel system specific, like a burst fuel line, faulty regulator or pump does not explain a boost leak at exactly the same time. In my mind it has to be a physical air leak, close enough to the injectors to draw a portion of fuel out with it. Suspect number one is the weakened not quite flat flange.
I am not understanding why your AFR goes so lean when you have the boost drop. Is your fuel table not set up at 150kpa and 6000rpm?
Dropping from 15psi to 6psi is not a small leak. Think of more than a 1/2" diameter hole in your manifold. That's what it would take.
If there was a fixed size hole, I would expect the boost would rise slightly with RPM. It is not.
Is your battery voltage constant through this event?
Is there a chance the inlet to the SC is getting blocked?
I am not understanding why your AFR goes so lean when you have the boost drop. Is your fuel table not set up at 150kpa and 6000rpm?
Dropping from 15psi to 6psi is not a small leak. Think of more than a 1/2" diameter hole in your manifold. That's what it would take.
If there was a fixed size hole, I would expect the boost would rise slightly with RPM. It is not.
Is your battery voltage constant through this event?
Is there a chance the inlet to the SC is getting blocked?
I was very surprised when I saw the AFR in the log too, I didn't clock it on the gauge at the time.
Fuel table is all setup for mid throttle all the way up the rev range.
Just checked the voltage - good shout - but it is constant 13.2V all the way up to, through and beyond the event.
I will check the air filter but I would be very surprised if something that big could get in there to actually block the filter to cause something like this, and it wouldn't explain the fuelling issue, again the ECU would just fuel to the new kPa. Its really quite tight for anything sizeable to negotiate through the bell mouth in the cowl (its right under the chassis arm that goes over the top of the arch, round the corner into the airbox.
No damage to the sc, or throttle body, both in working order, no damage etc. Bypass valve, my initial suspicion is also absolutely fine. I thought the return spring might have broken but its all good.
The drop in kPa was also physically verified with my mechanical boost gauge, its not the MAP sensor having an issue then under fuelling for the real higher kPa.
The 1/2" hole I don't think is unrealistic for the sort of gap that could be opened up with a flexing mounting flange.
1/2" hole is about 113mm2. Say I opened up a 0.5mm gap across the tops of the ports - 0.5mm x 50mm x 4 = 100mm2.
Same ballpark. I batch fuel too, so there is going to be fuel in the port with the intake valves shut, that could possibly be drawn out with a large boost leak.
As the revs increase the power to drive the sc increases, so force on the manifold increases. If the flange is deflecting it will deflect more at higher rpms, creating a larger hole - possibly keeping MAP relatively consistent as air flow increases.
Its all very hard to prove for definite but I can't think of anything else that would give all these symptoms.
Everything when inspected off the car is fine, no popped hoses etc, and fuelling was only effected in positive manifold pressures.
The fueling and boost leak issue are absolutely related, I don't see a simultaneous separate issue on two systems occurring in time with each other like this.
The flange looks thin. There is a lot of force going through it and I know the seal is not robust currently. Perhaps it was borderline strong enough before, and the small amount of material I have removed to try and flat it and the clearance in the lower mount bolt has maybe just weakened the system past a critical point.
Manifold is in the machine shop! Will be done this afternoon.
I tried out spraying water for the first time this weekend and of course it didn't go to plan.
Pump and valve sounded like they were working but minimal water was coming out the nozzles into the bucket I set up.
Quite a bit of headscratching testing things individually and it came back around to the solenoid, of course.
Manually grounding the solenoid and driving the pump resulted in a perfect spray, but with the ECU driving the valve only dribbles.
I am driving it enough to make a noise but not well enough for it to work properly.
I am going to use a gate driver to drive the gate on the transistor. I think it is to do with the size of gate resistor I am using (1kohm), to keep current levels low for the Tiny pins. At this low current the gate cannot charge in time at the 30Hz I am trying to drive the valve at.
Using a gate driver allows me to keep the current draw low on the Tiny, but use it to drive the gate with 12V instead of 5V and a load more current to make sure I really get it working.
The flow sensor also was not reading anything annoyingly. I had a conversation with Richard at Aquamist this morning and I have wired it up right in the car, and that it needs a pullup like I added in my ECU. I also tried manually tapping the signal wire onto a ground, to simulate a hall sensor and it didn't register anything in Tunerstudio. Not really sure where to go with this one as everything looks correct. I might swap pins on the Tiny to see if that makes any difference.
The beefed up manifold is back from the machine shop, nice and flat with a lot more meat on the flange. Hopefully that solves the vacuum leak, possible cause of the massive boost leak.
The MOSFET gate driver arrived, its a TC4427AEPA. I am using it to step up the gate voltage from the 5v 5mA (potential peak) signal the Tiny puts out to 12V and 0.8A (potential peak) to get the MOSFET gate charged nice and quick. It seems to have done the trick. I now have a nice progressive mist dependant on the PWM output duty cycle.
I worked out what was wrong with my PWM flow sensor - a dodgy solder on my input circuit. It all responds in the correct way to water flow now. Calibrating it is going to be a different matter but you can tell when the WI is on, when you've on purpose undone a line and if it isn't spraying. The transient flows between say 50% and 100% valve duty are going to take a bit of work but I have enough info to run the system now.
The issue I now have is when I datalog a lot of my Tinyiox info doesn't show correctly in the logs, it comes out with weird values, despite the gauges of these channels showing good info live on my laptop. I've checked the logging profiles and they all look setup right. I've emailed Jean to see if he can see anything odd. Hopefully he comes back with a fix.
I believe Tinyiox channels need to be mapped to generic sensors or all you get in the logs are raw adc counts.
I think that is an MS3 thing Ted - on my MS2 I don't have the capability to map generic sensors.
For my temp sensors the tinyiox passes the raw adc back to the MS2 through CAN. These datastreams are then used by some channels I have setup to convert from ADC into useful values for me. I understand the MS2 does not see these converted values, the conversion is done within Tunerstudio / Megalog viewer. The gauges for these channels work fine with the laptop plugged in while driving, but the logs from the same drive show completely different values. But it isn't consistent either. For instance my EGT logs. All the raw ADC for EGT came across fine and can be viewed in the log correctly. The channel EGT cyl 1 converted this ADC to degC successfully in the log. However EGT cyl 2---> 3 was complete rubbish in the log, despite the raw ADC being ok. I've checked the conversion on my channels and they are all the same. I will get there, these things are secondary at the moment, nice to haves, but I do want to get to the bottom of it.
The issue around the PWM input and PWM out duty cycle not being logged properly is slightly different. Both of these are raw data streams, I'm not trying to apply any conversions. I can see both of these datastreams reacting how they should with the laptop plugged in. The tiny is also triggering my map switch circuit correctly based off the PWM input values. So all appears to be working, then you look in the log and you get this: I'm manually operating the TPS to test the system. On the laptop and visually this test was successful. More TPS, more water, lower count on PWM sensor (more Hz, more water). On the log the valve duty and PWM input values are not what they should be. This is how the PWM output is setup for testing, equal to TPS
I can work around it for now, I just find it odd the info seems to be getting scrambled in the logs, but nowhere else.
I have got the supercharger back on the car, with the WI nozzles installed now. I took it for a brief spin and it seems to function as a car again. I didn't have any whistles or boost leak incidents which is good, hopefully beefing up and skimming the manifold has solved those issues. We will see.
I completed the work in the boot. I filled the tank with the anti surge foam and sealed on the access hatch, then mounted it. Wired up the level sensors and properly wired in the pump. I think it looks pretty neat, I'm quite happy with it.
I also had a conversation with Richard at Aquamist on Friday, namely about greater flow modulation and linearity of the water injection. He said that due to my relatively small flow volumes (approx 500ccmin) I need to use a restrictor before the PWM valve and that this will allow the valve to do a better job at proportioning the water flow.
He recommended 0.5mm / 0.6mm, stainless steel or brass. I can't find any for love nor money online so I have made a temporary restrictor by adapting the an-4 fitting before the valve. drilled the top section of the fitting to a slightly larger size, then filled that wider part with JB weld. When it had set I drilled a 0.6mm hole with a jewelry drill bit. It should be fine with just water, and because it fills a larger diameter than the rest of the pipework around it it can't really go anywhere, even if it comes loose. It should hopefully allow me to get the WI running properly for the trackdays.
So next steps are the first proper road test with the WI.
Still trying to fix the datalog issues with Jean.
Haven't managed to get a non weird dyno pull yet, but I have noticed that there isn't any puffs of smoke on first application of throttle after a period in vacuum, so the new seals in the supercharger seem to be doing their job
So I finally got a dyno run that wasn't odd. Its actually the best quality run I have ever done, no rpm smoothing in megalog and only a smoothing factor of 1 in virtual dyno.
273whp is the number it says. Rough maths from the AFR change info says this feels about right, also you can see that manifold pressure is lower, indicating a gain in VE. Its a bit hard to compare to my previous figures, because the old virtual dyno run was nowhere near as clean as this one, with a lot more smoothing applied, but I have tried below. Not really as clear cut as I expected really. The extra 18 bhp is all right in the top end, using the higher rev limit I have now set. Would have been interesting to compare the old exhaust up to 7400 - 7500 rpm, and see if virtual dyno saw the same torque drop off we saw from the extrapolated hp only dyno figures from when I got it tuned. I think one factor possibly effecting results is where I do the run. For instance I have seen now both times I have done a pull on the same slight incline virtual dyno has shown a reduction of 20whp. I honestly can't remember where I did the old dyno pull, on some back lane somewhere. From now on I am going to standardise this new location that seems to provide a good level surface that gives a run that requires very little smoothing. I will get it on a proper dyno sometime this year to do a proper back to back.
Other good news is the WI system is working great. I added the home made restrictor to the line pre valve and it gave me far more modulation of flow. I will say though it is not truly as proportional as I would have liked. I get a decent flow reading now for flow ranges between 250ccmin and 400ccmin, the new max flow with the restrictor. This isn't too bad, it pretty much means I can meter at 15-20% from about 4500rpm upwards, so that's ok. I went for a drive with it setup to roughly this mix and there was no hesitation or nastiness as the WI engaged. I could here it working and it switched over to the slightly leaner map. Still needs a bit more leaning out but its a start, and at this point I still did not have my logging properly working. I new the map was changing from my LED setup in front of me. Haven't got any interesting data yet but it works, so that's a start.
This evening I took the car out for another drive and things did not go so well. One good thing is I took my tablet instead of my laptop, and it logged all the fields correctly. There must be a file in my project on my laptop confusing things, I will take a look at that tomorrow, so getting there with that at last. Bad thing is the whistle is back and I had the same boost / fuel issue. I went to get on the throttle and the fuel leans right out and I can't make boost. I don't think the manifold flange is the issue here. It is stronger than it was before I mucked about with it adding the WI nozzles, significantly thicker and totally flat now. I remember when I had ignition issues, from my dodgy loom, that when the car was having an issue manifold pressure was limited / erratic, validated physically from the mechanical boost gauge. I don't know why it couldn't but I distinctly remember this factor. It doesn't feel like ignition again, that was more jerky, and also was not just in boost, but I think tells me that the manifold pressure can be affected by seemingly different issues. This probably sounds a bit mad, if anyone else has seen this effect when having fuelling or ignition issues let me know.
I think there is something up with the fuel system and my first suspect is my fuel pump. Its a few years old and the symptoms fit with a failing pump, inadequate fuelling under load. I have ordered a replacement pump and will order a new relay, and I will go over the grounds to see if that solves the issue.
On the whistle, it is appeared after a little bit of driving. When I got back home after the possible fuel issue, it was whistling away at idle its hard to tell where it is coming from to be honest. It definitely is supercharger side and towards the rear of the engine. I took the belt off and drove the car down the road and it no longer whistled. I'm not sure if it is an air noise, or a bearing noise at this point, but I'm not really convinced the whistle and the lack of boost / fuel issue are related.
Having loads of fun.
So the trackday on Thursday is off the cards at this point but I hope that I can make progress to try and sort the issues out for the two events at Curborough I have at the weekend.
Are you seeing the loss of boost on a mechanical gauge?
At one point I was having a problem where the boost line going into the megasquirt was leaking under full boost.
This would cause a lean condition and reported low boost.
Are you seeing the loss of boost on a mechanical gauge?
At one point I was having a problem where the boost line going into the megasquirt was leaking under full boost.
This would cause a lean condition and reported low boost.
Both ecu and mech gauge, but they share a line into the cabin, and the vac ref on the fpr is on it too. I will check this out this sort of thing could be the cause of the whistle too, thanks 👍
Both ecu and mech gauge, but they share a line into the cabin, and the vac ref on the fpr is on it too. I will check this out this sort of thing could be the cause of the whistle too, thanks 👍
Car is sorted! Oreo, thanks very much mate have a cat. It was the vacuum line where it joins to the hardline across the engine bay. The joint was slightly loose and as I pulled my intake off the rubber hose fell off the hardline. I fixed the connection and it all works again! So thanks for getting me to look at the obvious before I went down a spiralling tangent.
All ready for the trackday tomorrow now and get some good logs with the WI.
It fixed one of them... there are two it turns out.
After my test drive on Wed afternoon it was all working, no whistles. I drove most of the way to the track, and I noticed when I slowed down to stop for lights the whistle was back, and it filled me with dread.
I gave it some hard accelerations to test and I didn't experience the boost leak / fuel issue, so this whistle appears to only be audibly annoying rather than functionally an issue. It also only seems to appear with heat in the engine. Its coming from the back of the manifold / head area. It also sounds different from the original whistle. Anyway I will find it and kill it but it didn't spoil the day luckily, just made me very nervous to start with.
So really the day was a very positive one. The headline is the car was able to go out and lap as fast as I can drive it for as long of a session as I wanted and the car maintained performance for that period, which is ultimately my requirement for it.
It was quite cold (10degC) but coolant and more excitingly oil temps stayed right where I wanted them. Oil was basically 115degC all day and was stable. So the larger oil cooler and the WI look to have stabilised the spiralling oil temps I saw on my last trackday. The last trackday was hotter, but at 115degC I have plenty of room to take up these changes. Really happy.
The WI worked all day flawlessly, switching in and out when it should. Water usage if fine too, I could have easily gone the whole day on a single tank of water. For reasons that I am absolutely fuming about I don't have any data, but the car didn't feel like it was dropping power and I could put my hand on the supercharger after a run (it was warm / hot, but I could put my hand on it without pain). The straight line performance was pretty incredible if I'm honest, and this was maintained through the runs. This track has a couple of decent length straights. The longer of the two I was well into 6th gear after changing at the limiter in 5th, which is well over 130mph, and the other straight I was easily able to achieve the limiter in 5th. This was consistent over the duration of the sessions, and is a big step up in straight line performance from my M45 setup. There was a couple of Ford Fiesta Sts there which I used to be pretty on par with down a straight. Now there is a significant speed difference in my favour.
The exhaust sounded great, although I did have to adjust the hangars a bit due to one of them falling out under thermal expansion, but I fixed it and it wasn't a problem again. No other issues with it which is good. Various people told me it was very spectacular being come past on the straight as every gear change it would spit flames and coming into braking zones was almost a continuous fireworks show. I toned it down a bit on the tune after that, the old exhaust was a lot tamer and didn't really spit or flame, this one appears to do it at every excuse. Its cool to spit a bit of fire but I don't want it to be too ridiculous and set my bumper on fire.
Brakes, tyres and new coilovers worked well all day. Brakes where very confidence inspiring actually, I didn't lock once and was having great fun in the big braking zones coming down 3 gears heel and toeing. I am running slightly less camber than before (2deg down from 2.5-3deg) so I wonder if that has helped out avoid front lockups I struggled with last time on the same pad setup. Also this gearbox worked well, didn't miss any shifts all day, unlike last time when it was virtually impossible to select 4th. The box is better certainly, but also the new engine mount setup holding everything in place has really helped. The mount also seems to have bedded in now. More vibration than the old setup certainly but perfectly acceptable for the use of the car.
Coilovers felt like they offered more body control than before and where better on the curbs. They have the new valving that Meister use for high speed damping and I was very impressed. The car is more balanced than before, it was quite twitchy at the rear. The significant increase in front spring rate particularly has delivered a car with a more balanced feel, which is good as there is more than enough power to adjust the balance at any point during a corner.
The tyres are the new AD08RS. I had the old R and then went to a stickier MRF ZTR. I enjoyed driving on the new RS. They are softer sidewalled than my ZTRs and the car moved around a little more. Hard to compare to the old R because that was 3 years ago now. But the RS stayed together without starting to feel like they are overheating, and certainly inspection after each session showed no signs of degradation. I do prefer the track driving on the ZTRs they are a more precise weapon, but they are also £50 more a corner. The RS did exactly what was asked of it so I cannot complain really.
There was a turbo mx5 there, 250crankhp but on stickier tyres than me. We had a great tussle for several laps. He was slightly faster in the corners but down the straight and in the brakes I would reel right back to him. It was fantastic fun and we had a great chat afterwards. I didn't get this session on video which I am gutted about but there we go, it was very entertaining.
Really the only proper kick in the nuts came when I got back home and discovered non of my datalogs had saved properly on my tablet. Absolutely fuming about it. I tested it on the wed afternoon and it all worked perfectly. I think it was because I was turning the car off before turning the log off. So I won't be able to get the MAT and EGT data when properly in it for a long session until start of July now.
I think I would be even more annoyed if the car was having issues, but as it worked all day driving as fast as I could overall I am very happy with the car and feel a lot more confident in it now. Just need to find this whistle which I hope doesn't take too long.
I only took one video which I was stuck behind a Caterham on, and you can't really hear the exhaust properly but it does give an idea of speed in a few places, so I will upload that soon. I've got Curborough on Saturday so I will ask my mates to get some outside vids down the straight to let you all hear it.
3 events and 4 days and it is still in one piece (sort of, the engine is anyway ) . I had two events at Curborough over the Easter weekend, one was a small private trackday and the other was my first Autosolo competition with a car club I recently joined. Both days were a lot of fun and I am very happy to say I didn't have any drivability issues at all. The car took me bouncing it off the limiter, hard launch control use and general abuse in its stride.
I've got a couple of bits to repair, I had a bit of an excursion off onto the grass after trying to channel my inner rally driver, backing it into a tight left hander that opens out on the brakes before 3rd gear powersliding it out as it opened up. Just ran out of road on the exit and went on the grass a little (only dropped 0.5sec on the lap though ). This caught my oil cooler scoop and bent my undertray a little, but I adjusted it back with a hammer and off we went. The other bit of damage was to the front bumper when I lost one of the indicator housings after coming in a bit hot into some cones. This is more annoying to repair as the indicators I used don't seem to be available anymore and I need to make another housing with fibreglass.
I did pretty well in the Autotest, I'm quite happy. I was 3rd in class (out of 5) and 21st overall (out of 60+cars). I was third fastest overall on one of the tests, and would have placed a lot higher if I hadn't got a dropped test when I hit the cones that damaged the bumper. You do 3 tests, 4 times each, no drop scores so a drop test really hurts, and in my case was equivalent to a 20 -25 second penalty. I clipped a cone on another test too which I think is a 5s penalty. So there's promise there, particularly on the faster tests that I can use the power on. Anyway it was a huge amount of fun with great people and a driving style I haven't done before.
I seem to have found the whistle! It was the throttle body gasket / bolts. I applied a smear of sealant to the gasket and in the threads of the bolts and it has gone away. The amount of land inside the bolt holes is small, as I made the sc inlet a slightly larger diameter than the tb to avoid an inwards step for the air charge. This limits the sealing area for the gasket, and so I think that the bolts can end up needing to be sealed if the tb position is slightly different and I think the threads in the ali plate are becoming weaker as I remove and replace the tb. I've already had to helicoil one of the threads. The sealant is a short term fix, I'll do something better next time the sc is off.
Also since fixing the vacuum line manifold pressure without WI has returned to around 14psi, but AFR has remained at 12. So the exhaust has leaned the fuel slightly, but it was not responsible for a drop in manifold pressure that I initially perceived as an increase in VE. Personally I don't think the exhaust is doing a huge amount over what the old one did, certainly not 'uncorking' the system like I had hoped. I think the increase in rev limit is more responsible for the peak power increase. I guess the question is would the old exhaust have allowed the same high rpm gains or is this the benefit of the new exhaust system (high rpm power support). I guess you could question what the point is if all the gains are say above 6500rpm? How much benefit is that? For me there is benefit. I track the car, I enjoy driving it up in that rpm range and I use those revs. To me it feels like it pulls like a freight train up there and it is exciting and sounds great. So knowing the power isn't rolling over and using these rpms has a point is all the better.
I've got some interesting starter data from the first trackday, I'm going to try and order it sensibly because there is a lot to show and discuss.
WI and effect on manifold pressure - spraying into the back of the sc has realised a gain of about 0.5-1psi in manifold pressure. On a two gear pull without WI I see around 14psi in the first gear, 14.5psi in the second (I think due to the increase in heat during the acceleration). With WI I see around 15psi, interestingly stable across both gears - maybe a clue there that the WI is helping stabilise temps during extended throttle applications.
WI and effect on MAT - errrrrrr..... Well I think it is safe to say that I don't see a step reduction in temps with the WI on, but I think there are a few things at play here. I guess you could look at this from a couple of different angles. Top graph is WI off, bottom graph is WI on which also shows EGT temps, WI flow rate and fuel injector pulse width
Angle 1 - After a two gear pull of practically equal length in the same ambient conditions MAT was roughly 6 degC lower with WI spraying, despite a small increase in manifold pressure from better rotor sealing / sc efficiency.
Angle 2 - With WI off MAT only increased by about 5degC over the pull whereas with WI on MAT increased by about 7degC. I think this has more to do with the starting temperature of the pull. The system is sensitive to heat soak from the engine, the charge cooler is bolted to the cylinder head, and at Curborough only one person is allowed on track at once so you can be waiting in line for a while sometimes. The effect this seems to have is that at lower air flows during the runs, off throttle, low throttle etc air temps are higher because the smaller amount of air is heated more by the heat soaked components. At high air flow rates there is more air so the heating effect is proportionally less and a temperature nearer the 'true' MAT is seen. This closes the temp gap to a run without a heat soaked system, by way of a smaller increase of temp in comparison when on throttle. That is my take on it anyway. You can see in the MAT max and min values that the WI off run min and max values of MAT are 7-8degC higher than the WI on run so as an average the system was hotter for the WI off run. The WI is only on for short periods of WOT, it isn't reponsible for the lower average temps. The system is actually at its hottest when idling at standstill and when off the throttle coasting down after a pull.
This is really why I wanted the data from Cadwell to show temp info over the course of a track with far longer periods of WOT that I think would be more telling.
WI and effect on power: So far this seems to be positive, certainly not negative. The PWM valve is doing a good job of proportioning flow, see graph above, and I haven't come across any stumbling etc with WI on, even though I am still a bit rich up to 6.5krpm. My WI map is still very tame, only a very small lean out over the non WI map but I think we are seeing results already. See graph below.. Red trace is WI on, blue is off. Please bare a couple of things in mind - blue run was done before I fixed the vacuum pipe so shows the lower 13.5psi pressure that should be 14psi. Also the rpm range 5-6krpm torque gain on the red WI run I think is to do with a bit of wheel slip as I was just exiting a corner. The straight at Curborough out of that corner is nice and flat so should be a good comparison otherwise. Also the wheel height is slightly taller on the red run as I swapped to my track tyres, the AD08RS that are a slightly bigger size 205 50 r15 vs 195 50 r15.
With that out the way you can see that in the upper rpms there is a small but clear increase in power and torque with the WI on. This is with a very small lean out and no ignition advance change between WI on and off. The extra 0.5psi is probably helping as well as the supposed increase in sc efficiency. Looking good and I will continue to have a play. I spoke to Dale my tuner and he recommended not pushing AFR to much, keep it at about 12 - 12.2AFR with WI on, and then use the ignition timing advance more as this will have a greater effect on power and also do a better job of keeping exhaust valves cooler, so that is the direction I will go down.
I see your Max TPS is 103.6% in post #135. Are you concerned in any way? I'm running a Rotrex and the OEM throttle body, and I was seeing 101.4% Max on the TPS. Turned out the mechanical stop on the throttle body lever had dug/smashed a groove in the aluminum boss at the bottom passenger side of the TB. I propped the throttle all the way open and measured using two small straight edges and sure enough, the butterfly was opening past 90 degrees. It's hard to tell with the naked eye. I filled the groove with JB Weld, but have not yet had her back out on the road.
I see your Max TPS is 103.6% in post #135. Are you concerned in any way? I'm running a Rotrex and the OEM throttle body, and I was seeing 101.4% Max on the TPS. Turned out the mechanical stop on the throttle body lever had dug/smashed a groove in the aluminum boss at the bottom passenger side of the TB. I propped the throttle all the way open and measured using two small straight edges and sure enough, the butterfly was opening past 90 degrees. It's hard to tell with the naked eye. I filled the groove with JB Weld, but have not yet had her back out on the road.
The TPS going above 100% was actually because I had the tps off the tb when looking for the whistle and I did a rubbish job resetting the values in tunerstudio. I noticed about halfway through the Saturday the car wasn't going into idle mode properly because min TPS was above the idle advance threshold, and I reset it again.
I don't think the stops have moved in anyway but I will take a look next time I'm in the area. I actually struggle to get the TPS to get to 100% when 0% is idle stop 100% is full open stop. Normally I only get about 97% with the available pedal travel.
03-20-2021, 07:10 AM
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) . I had two events at Curborough over the Easter weekend, one was a small private trackday and the other was my first Autosolo competition with a car club I recently joined. Both days were a lot of fun and I am very happy to say I didn't have any drivability issues at all. The car took me bouncing it off the limiter, hard launch control use and general abuse in its stride.
). This caught my oil cooler scoop and bent my undertray a little, but I adjusted it back with a hammer and off we went. The other bit of damage was to the front bumper when I lost one of the indicator housings after coming in a bit hot into some cones. This is more annoying to repair as the indicators I used don't seem to be available anymore and I need to make another housing with fibreglass.
