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Lucky escape on that one mate! But would certainly explain a dip in power.
Have you tried it out now the timing is corrected? Remember to reset your spark timing too because it will shift when you correct the cam if you are running the exhaust cam driven CAS
Lucky escape on that one mate! But would certainly explain a dip in power.
Have you tried it out now the timing is corrected? Remember to reset your spark timing too because it will shift when you correct the cam if you are running the exhaust cam driven CAS
I have not started it yet and was unsure of what adjusting the cams would do. This is all a first for me.
Slowly but surely putting things back together and making changes with things I wasn't happy with.
I finalized the 2nd spring for the 70mm throttle body. The original one didn't have what it took to return fully closed and I'm very happy with how this turned out. I lucked out the throttle wheel had this location to mount the 2nd spring and the SC had the perfect spot to mount the spring to it. Found a local engine machine shop and had them shorten this throttle body (by 13mm) to give me extra clearance for the intake. I also had them resurface and true up my blower outlet manifold flange to make sure I had a good sealing surface between it and the blower, apparently it needed it.
Originally when I used my 62.5mm nose pulley from TDR it sat closer to the blower than the stock pulley. I was unable to move the blower forward enough to line it up with the crank pulley and the belt would come off. I ordered some 16.5mm washers and used my Dremel to notch it to to go over the locating (?) spline for the nose pulley. The washer is copper because this was what was available in that size, I think copper will work fine although you don't often see it used.
I would have everything back together already but got sidetracked yesterday installing these AWR front sway bar chassis mounts. What a PITA especially if you have power steering as the lines have to be disconnected and run through the driver side one of these. I also managed to snap 3 bolts and after I got them installed I realized I had installed them backwards. Yesterday was a struggle but tomorrow I'll get everything back together and get the engine timed in MegaSquirt which should be easy but it's a first for me.
Back on the dyno this Friday and I just now have everything back together.
Originally my m45 kit had a dual throttle body setup which is what I've been trying to make work with this new kit. The ratio between the the pulley's was off and the TB at the blower was only at 80% WOT when the intake was at WOT. On a hunch I bought a cheap ebay throttle wheel for a Silvia/240sx and it looks like the perfect size to solve the issue.
A quick trip to Amazon Motor Sports and I had everything I need to build this new intake. It's not ideal especially with the 3x 90's I had to use coming off the TB but it's solid and I'm guessing it will flow better that the "flex tube" you see so often with these mp62 kits.
Amazingly when I went to set he base timing in MegaSquirt it was right on already and didn't have to make any adjustments in the "trigger wizard." It has a bad idle surge and idles high after the retiming but I imagine those are all tuning issues. It ran and drove great so I'm hopeful my next trip to the dyno will be a success.
Hard to say if it was stronger as I never went into boost during the drive. If I had to say if it felt the same or stronger than before the timing correction I would say stronger but again not going past 3k rpm it's subtle.
Eventually the intake is going straight from the TB through the hood, promise. This will do for now.
Got back on the dyno yesterday and the car made what I thought it was supposed to with the given mods. Made 213 whp @6,500rpm and 178 ft/lbs. The graph shows a Dynojet correction number as 242 whp and I'm sure if I had them rev it to 7k it would have been in the 250's. This run was done on my 140/62.5mm pulley setup, with 93 octane and saw 13lbs @6500.
So far I have driven the car twice, from the dyno home and from home to work. I'm underwhelmed with the torque and the way it's delivered. The torque is much smoother and more progressive and lacks the punch my m45 seemed to have. Again I've only driven it twice and I'm currently having some cooling issues that are keeping my from really beating on it. I'm hopeful once I figure out why I'm running hotter than I was I can drive the car the way I want to and the power will be more apparent. If this setup is at 242 hp on a Dynojet my torque should be in the 200's at least but it doesn't feel like it. I still have not done a boost leak check yet but have everything I need to do so, maybe that will shed some light on things.
I am happy to be driving it again and the horsepower is pretty satisfying.
Yeah, that dyno doesn't look right. You say you hit 13psi, but you don't say where. Post a screen-shot of a pull from 1500 rpm or lower with AFR, MAP, RPM, and spark advance, cursor at 2500 RPM.
Also post screen shots ot your timing and AFR target tables.
Yeah, that dyno doesn't look right. You say you hit 13psi, but you don't say where. Post a screen-shot of a pull from 1500 rpm or lower with AFR, MAP, RPM, and spark advance, cursor at 2500 RPM.
Also post screen shots ot your timing and AFR target tables.
Are you asking for a data log from a street pull?
The person tuning the car said he saw 13 at the end (6,500.)
I feel like there should be more area under the torque curve before the peak and that's what driving it feels like. Is that what you're referring to when you say it "doesn't look right?"
TQ on a 62.5/140 MP62 should look like a stock curve moved up (vertically) from about 2000 to redline. Yours looks like a rotrex. First inclination is that you still don't have your cam timing set correctly. Second is that the car is very poorly tuned.
Yes a street pull. You should request that your tuner capture logs on pulls as well.
TQ on a 62.5/140 MP62 should look like a stock curve moved up (vertically) from about 2000 to redline. Yours looks like a rotrex. First inclination is that you still don't have your cam timing set correctly. Second is that the car is very poorly tuned.
Yes a street pull. You should request that your tuner capture logs on pulls as well.
These are two separate logs one is of the "defualt" option and the other of the "tuning" window in MegaLogViewer. It was pretty busy out and tough to do a clean pull. Please let me know if these show what you needed to see. I'm new to this program and your patience is appreciated.
See, isn't that fun? Remember to post both the tune and the log files for those who will look at them. For logging in tunerstudio, you don't have to try to start and stop the logs at the perfect time. Make sure you have it set to max reads per second, and that you are logging all of the available fields in the logging profile menu. You can grab logs that are minutes or even hours long if you want. Start the log before the pull when convenient and safe, don't worry about a delay between log start and the pull. When posting screen shots, try to zoom into the area of interest as best you can to maximize the screen width.
You posted the injection timing table, which has some questionable settings depending on how you have your injection timing setup, but what we want to see is your spark timing, or ignition timing.
Now, you should be able to see that your fuel is not well controlled right now. You are targeting high 11s at that 150kpa 2500 point and are getting high 10s low 11s. That is a pretty strong initial sign that the tune needs work.
You will want to go full 100% tps when doing pulls.
This looks like a 2nd gear pull, 3rd is better, but even this pull makes me question the dyno results. The slope of the RPM line is really pretty constant, which is indicative of a constant torque, but the dyno plot doesn't support that.
For the G4 MP62, SC VE is really kinda ~there by about 4krpm at the SC, which nominally equates to something around 2krpm on setups with the 62.5 snout. I can't really take any data directly from my application because the SC has bee transitioned out of the picture by 4krpm, and I start compounding at 2k or lower, but I can say that with a 62.5/140 on my car I have a full 24psi by 2800 and am at 15psi by 2100. At 2100, I am probably only getting about 1-2 psi of compound from the turbo.
Here we have ~ 7psi at ~2500, which doesn't sound right to me. Now that can be a function of belt slip, but it can also be indicative of excessive valve overlap, boost leaks, bypass problems, leaky BOV, leaky ISC, supercharger case porting ....
Look at the TDR dynos, they start their pulls too late, which results in what looks like spool-up (for lack of other comparisons), but they all start to conform to the stock TQ curve shape by ~3krpm. This implies that the SC is delivering the target pressure ratio at this RPM.
This is a snap of a typical data log on my setup, boost being the red line.
It makes 183kPa by 3.5krpm, ramping up to the full 200kPa by 5krpm then basically flat until redline.
I tried digging out log from my M45 but I couldn't find one that illustrated anything particularly useful. I do remember the pressure used to build to maximum lower in the rev range than my Autorotor, but again would hold this peak pressure across a wide portion of the rev range.
This being in comparison to your trace Cincykemo, which looks to be a pretty steady upwards climb. Odd for a positive displacement charger.
I think all Ted's suggestions for the cause are good ones. If you find an issue that is causing the lack of low end boost you should find your lacking low / midrange comes up nicely.
Bearing in mind the cam issue you found maybe cam timing deserves another in depth look, is the cam dowel still holding up or has it sheared a bit / slipped etc.
See, isn't that fun? Remember to post both the tune and the log files for those who will look at them. For logging in tunerstudio, you don't have to try to start and stop the logs at the perfect time. Make sure you have it set to max reads per second, and that you are logging all of the available fields in the logging profile menu. You can grab logs that are minutes or even hours long if you want. Start the log before the pull when convenient and safe, don't worry about a delay between log start and the pull. When posting screen shots, try to zoom into the area of interest as best you can to maximize the screen width.
You posted the injection timing table, which has some questionable settings depending on how you have your injection timing setup, but what we want to see is your spark timing, or ignition timing.
Now, you should be able to see that your fuel is not well controlled right now. You are targeting high 11s at that 150kpa 2500 point and are getting high 10s low 11s. That is a pretty strong initial sign that the tune needs work.
You will want to go full 100% tps when doing pulls.
This looks like a 2nd gear pull, 3rd is better, but even this pull makes me question the dyno results. The slope of the RPM line is really pretty constant, which is indicative of a constant torque, but the dyno plot doesn't support that.
What is your idle vac (map) and rpm?
I could not find the "max reads" options for logging in MS. I'm now using MS Ultra and MLV HD. I took this pull last night on the same tune I did the dyno run on in 3rd gear. Please lmk if this way of formatting the logs and pictures works or what needs improved.
I just started working remotely with a very reputable MS/Miata tuner here in Ohio and received my first revision last night. He said "your timing table in boost below 2300 rpm was way off from what it should be, no doubt creating lack of torque." I loaded the tune and went out late for a short drive. There was definitely an improvement in the low end but I still don't think it's where it should be. He also went on to say "your timing table in boost above 2300rpm is VERY aggressive." I do not have a log of this tune yet but below is the revision of the timing table (original table posted a few reply's ago.)
Tonight I will be pulling the valve cover and upper timing cover to recheck mechanical timing. Tomorrow I will attempt to do my first boost leek check. I have an air compressor and fancy coupler with gauge and tire style valve stem. I planned on cracking the throttle bodies open, removing the oil cap, pressurizing the system at the SC TB and using the soapy water method on the possible leak points. I plan on starting at 5psi and working my way up to 12-13ish for the test. Any suggestions are welcome.
Timing Checked out.
I had a socket extension in the cylinder to check for TDC as well as the crank pulley timing marks.
I had a direct picture of the exhaust cam gear but couldn't find it. It lined up as perfect as this intake cam with the mark.
For the boost the leak check I used an air compressor, cracked both throttle bodies, pulled the oil cap, pressurized the whole system from the supercharger TB and used soapy water to look for leaks. I had slight leek at the super charger throttle body but am not concerned as that is a non pressurized part of the system under actual boost conditions. I checked the couplers (x4), intake TB, vacuum lines, brake booster, BOV, bypass valve and around the blower outlet plenum. Although I forgot to spray the side of the intake TB where the spring is.
The only leak I came up with was the BOV. I disassembled the BOV per Turbosmart's instructions, cleaned and relubed it with hydraulic oil. The piston or housing showed no scoring and seemed to be in good shape along with both rubber o rings. What you see in the video bubbling is excess oil I used to lubricate the piston. I also tried to see if the pressurized air was moving the piston at all and from what I could tell the piston did not move under pressure.
This is a video of the pressure drop. I have no frame of reference if this is good or bad. Idk if it's the compressor but for some reason the system would not pressurize past what you see in the video.
A log from today after the first revision I've got from my new tuner.
Well I have been wrong before, maybe that is what you get from an MP62 at 2500. I bet Tom at FFS can give you a definitive answer on the topic. Your tune already looks way better just in that 1 plot. I bet the butt dyno can tell as well.
Well I have been wrong before, maybe that is what you get from an MP62 at 2500. I bet Tom at FFS can give you a definitive answer on the topic. Your tune already looks way better just in that 1 plot. I bet the butt dyno can tell as well.
I'm still a little underwhelmed with what my butt dyno says except up top where apparently the timing is still "very aggressive." I have the flex fuel sensor so I can go E85 to retain some of that timing. I don't feel like running anymore of an aggressive pulley ratio than I am. I really hoped to get that low end punch out of this setup.
Any thoughts on the BOV leak?
Tom is a great source of info. He just sent me an auto tensioner mount (doesn't sell anymore) and I've sourced a few things from him already. Super good dude.
I'd like to get back on the same dyno once I get a few revisions on the tune under my belt. I'll keep tweaking and trying to find inefficiencies. I'd really like to copy Tchaps KPA in the log he posted. He has a twin screw and I thought my roots blower would build boost similar to his.
08-17-2021, 12:47 PM
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