When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Dyno Tuning - Not making real power - EBL Data logs
Hi all,
This past weekend I drove to Los Angeles to dyno tune my car. Kevin and DynoDon were helping me. We ran into a really odd issue that we couldn't really figure out and was hoping to get some ideas from you guys.
I found a really cool website that allows me to share a data log so here it is: Dyno_Data_Log
Before we go into the details, this is how DynoDon mentioned the engine felt: As soon as he went WOT, the engine would just fall over and not feel good at all.
This is also exactly what we saw on the Dyno graph. A very quick jump in power then the engine would just relax and continue to chug away but not making much power.
The odd part about it is that everything (besides the power) was reading decently: AFR's were within a good range, fuel pressure PSI continued to rise with boost, boost continued to rise steadily w/ RPM, and no knock counts while WOT.
We concluded that something was wrong with my setup and eventually stopped after we saw that none of the changes we were making were going to bring the engine to life.
Here's a few videos of some of the runs we made on the dyno in case it helps to hear the engine:
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Napster134
Hi all,
This past weekend I drove to Los Angeles to dyno tune my car. Kevin and DynoDon were helping me. We ran into a really odd issue that we couldn't really figure out and was hoping to get some ideas from you guys.
An MSD EFI Distributor and MSD Blaster coil
This is most likely the problem. Notice in the graph how the RPM varies, The ECM calculates the RPM via the distributor reference pulses (DRPs). If you have a stock GM small cap distributor and coil try them and see how it is. The GM 369 ICM is also recommended.
Use a standard cooper core plug such as the Autolite 3923 gapped at .032".
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by RBob
This is most likely the problem. Notice in the graph how the RPM varies, The ECM calculates the RPM via the distributor reference pulses (DRPs). If you have a stock GM small cap distributor and coil try them and see how it is. The GM 369 ICM is also recommended.
Use a standard cooper core plug such as the Autolite 3923 gapped at .032".
RBob.
Right. My two thoughts are spark quality or something engine internal and this is along those lines...
I recently replaced the cap, rotor, ICM, and pickup with brand new MSD parts. I did not replace the coil though!
Technically, there is still something weird going on again with this distributor:
With the key on, engine off: I tap the brake pedal and my fuel pump primes.
The last time I troubleshot this issue, it was due to the fact that my distributor was not grounded properly. I ended up fixing it with a ground from the distributors hold down to the firewall. After a few years of letting the car sit, I came back to find that the whole “brakes causing fuel pump prime” issue was back.
The other day while troubleshooting an unrelated issue (which turned out to be injector wires being broken), I replaced the distributor and coil w/ an Oreilley’s set. I noticed that with the Oreilley’s parts, I wasn’t hearing the weird pump prime issue with the engine off. I ended up returning it and putting the MSD setup back in once I found ignition wasn’t related to that issue.
Also, the plugs I’m using are NGR R FR4 V-Power plugs.
They do have a 3/4” reach for the heads I have but I’ll swap out to the Autolites. They were also recently replaced.
Last edited by Napster134; Aug 10, 2018 at 10:39 AM.
Re: Dyno Tuning - Not making real power - EBL Data logs
I don't have any experience with SC, but is it possible with the
110 LSA cam it was just blowing the charge out the exhaust valve?
Or the injector pod on the throttle body the fuel interrupting & air flow (TBI blow through).
It didn't really feel like it was missing. AFR was steady about 13.5 all the way across.
Last edited by Dyno Don; Aug 10, 2018 at 12:38 PM.
Re: Dyno Tuning - Not making real power - EBL Data logs
I agree. Symptoms match spark blow out under load. You should consider 1 step colder plugs. NGK recommends 1 step colder for every 100 HP over stock. We often go two steps colder on really high boosted applications.
If it is the MSD components that's too bad. Might call them and ask if they have something more suitable.
Re: Dyno Tuning - Not making real power - EBL Data logs
I would normally go 5 heat range on that in low boost. Gap it .020-.022 on stock type ignition. My 305 would not light off til i went very tight on gap. Not sure why but is what it is lol
Re: Dyno Tuning - Not making real power - EBL Data logs
Hmm... So I believe that I gaped these at 0.030".
I know that I gaped them a bit tighter than stock (0.035") due to it being a boost application.
The highest amount of boost that I've seen (when the engine was running properly about 4 years ago) is 8PSI (based on the 2-bar MAP sensor)
As for the MSD components, they have been in the car for quite some time (5+ years) . I've replaced the internals of the distributor but maybe it's still not working properly.
I'm going to try a new distributor and coil and if that doesn't do it, I'll start tightening up the gap and see if that helps.
Orr89RocZ, when you say your "305 would not light off til [you] went very tight on gap"...
Was the power loss as bad as what I'm seeing? I figure you're seeing a ton more boost than I've ever seen though w/ turbos.
Re: Dyno Tuning - Not making real power - EBL Data logs
My 305 was on 8-9 psi. I gained nearly 80 hp with plug gap change alone. Now i did have valve float issues above 8-9 psi. But it went from mid 14’s at 95-96 mph on 7 psi to 13.5’s at 109 mph with gap change
my big boost car also had ignition issues similar. Car felt ok but wasnt responding to air fuel changes and i gapped tighter and increased spark energy. Went from 160 to 165 mph
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Dyno Don
I don't have any experience with SC, but is it possible with the
110 LSA cam it was just blowing the charge out the exhaust valve?
Or the injector pod on the throttle body the fuel interrupting & air flow (TBI blow through).
It didn't really feel like it was missing. AFR was steady about 13.5 all the way across.
That is WAY TOO LEAN! Try getting the air/fuel ratio down around 11:1, then slowly work from there. Also depending on the amount of boost pressure you want to start the timing very conservative. I would program anything over about 4 psi to 16* of timing as a good starting point. Maybe simply a case of too little fuel and too much timing. From what I remember my Weiand 177 blown 350 TBI at 10 psi of boost liked about 22* of timing all in by 2,600 rpm on 93 octane and a WOT air/fuel ratio of 11.5:1.
Re: Dyno Tuning - Not making real power - EBL Data logs
Fast355 is right about that. If the AFR under boost is 13.5 that's too lean. Usually you want around 11.5 to 12.5 depending on the engine. Ignition timing varies GREATLY depending on engine efficiency. Start with no advance under boost. Engine's with highly efficient head designs do not need much. Advance is a crutch used by inefficient combustion chambers to light off the burn in "advance" of the approaching piston to give the flame front time to propagate and reach the piston face just after TDC. Engines such as the Mitsubishi 4G63 have extremely efficient intake, exhaust and chamber designs and will not tolerate more than about 3-5 degrees advance under full boost. Though engines with more "normal" efficiency will probably be closer to 20 degrees.
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by RBob
The odd thing is, is that the dyno graph shows the AFR starting rich, rising to about 12:1, then dropping into the 11.n:1 range.
RBob.
sorry, we did quite a bit of runs that day. We didn’t actually get datalogs of all the runs. In all cases, whether the AFR was 13.5 or whether it was what you see in that specific datalog, the engine was reacting the same. I don’t think that we even made it into 5k RPMs due to the obvious issue of going WOT and the engine just not reacting.
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by GeneralDisorder
Misfire will drive the AFR richer.....
On-board wideband not agreeing with the dyno sniffer?
GD
The onboard and dyno WB’s were a bit off at idle (or maybe it was just when we first started) but at WOT they were more aligned with each other.... from what I remember...
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by RBob
This is most likely the problem. Notice in the graph how the RPM varies, The ECM calculates the RPM via the distributor reference pulses (DRPs). If you have a stock GM small cap distributor and coil try them and see how it is. The GM 369 ICM is also recommended.
Use a standard cooper core plug such as the Autolite 3923 gapped at .032".
RBob.
Rbob, do you have an example of what a proper RPM graph should look like?
Last night, I went far back (to 2011) and pulled a N/A datalog I saved from a 14.33 second 1/4 mile run at Famoso Raceway. This is when I know the engine was running okay and I compared the RPM graphs. While the one from 2011 does look nicer, it’s not a huge difference. Here’s that run:
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Napster134
The onboard and dyno WB’s were a bit off at idle (or maybe it was just when we first started) but at WOT they were more aligned with each other.... from what I remember...
Your onboard WB was showing about 1 point richer than the dyno WB, but they followed the same curve.
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Napster134
I don’t think that we even made it into 5k RPMs due to the obvious issue of going WOT and the engine just not reacting.
Nap, that website that provides the free datalog reading makes my damn eyes hurt. Take the car out for a spin, set for a datalog with the EBL, and try to bring the engine up to 5000-5500RPM on the highway, then upload that datalog here...
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Street Lethal
Nap, that website that provides the free datalog reading makes my damn eyes hurt. Take the car out for a spin, set for a datalog with the EBL, and try to bring the engine up to 5000-5500RPM on the highway, then upload that datalog here...
- Rob
Sorry about that!
Actually, I have an EBL data log from the dyno day.
As for running it up to 5000-5500 RPM, I'll be with the car next week.
This is when I plan to do all the testing. So far, based on everyone's suggestions (and some of my own ideas), I plan to try the following:
Take the car out, try another run w/ data logging enabled. (in order to get a baseline) If it feels okay, I'll take it up to 5500
Try a new dizzy and coil
Take the car out, try another run w/ data logging enabled.
At this point, I expect I'll know immediately if the issue was fixed or it'll be very obvious I still have no power.
If all else fails, I'm going to run a compression test.
If this checks out, tightening the spark plug gap, and reducing SA will be next.
Re: Dyno Tuning - Not making real power - EBL Data logs
Just want to take a peek at your injector duty cycle. If we consider your car is 3500 pounds when you ran that 14.33, this tells us your making about 225 to the wheels naturally aspirated give or take a few. At 5 pounds of boost you should be seeing about an 80 horsepower increase over that. I tried looking at that datalog despite my eyes hurting, and that data looks good, everything rising in accordance to what is needed. However, the dyno is still showing naturally aspirated horsepower numbers, 221 to the wheels when it should be closer to 300 to the wheels with 5 pounds of boost pressure. Let's take a look at the EBL analysis...
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Street Lethal
Let's take a look at the EBL analysis...
- Rob
EBL is showing 90% Duty Cycle at 4300-RPM and you let off immediately after, about 290-RWHP up until that point eventually hitting 300-RWHP if you reached over 5000-RPM, possibly a tad more if you bring it closer to 6000-RPM at 5 pounds of boost pressure. So, the fueling is there, and if the WB is accurate on the dyno as well as in your system, then there might be a problem with the dyno stream connection...
- Rob
Edit: Bob, look at his g/sec under boost pressure.
Last edited by Street Lethal; Aug 17, 2018 at 07:28 PM.
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Street Lethal
EBL is showing 90% Duty Cycle at 4300-RPM and you let off immediately after, about 290-RWHP up until that point eventually hitting 300-RWHP if you reached over 5000-RPM, possibly a tad more if you bring it closer to 6000-RPM at 5 pounds of boost pressure. So, the fueling is there, and if the WB is accurate on the dyno as well as in your system, then there might be a problem with the dyno stream connection...
- Rob
That all makes sense... here's the thing...
This may all be in my head... But, my car was fast at one point. Or at the least: It felt fast... much faster than it feels today.
The night I ran 14.33, I don't believe it had even been tuned via a WB yet.
Back in the "good" days (about 5 years ago), everything was running great... until one day, I ran into an issue where the engine would pop and chug under the slightest of load.
I parked the car, moved away, and finally was able to come back to the car last year.
I found the 2 wires connector between the distributor & coil was fried. This was replaced and most of the popping went away.
I then replaced the throttle body: That got rid of all the popping.
The only problem left was: It didn't feel fast anymore. The engine chugs along, but it's nothing like before. I assumed the problem was: The tune.
The first pass DynoDon went WOT, he immediately asked me "How does the car feel when you actually drive it?"
I mentioned that "It use to feel fast, but lately, not so much..." and he confirmed: He also felt like the engine was relaxing as soon as WOT was hit.
Anyhow, this is all based on feeling, as for the facts:
We see what you see too: Decent values across the board. Nothing seems too out of the ordinary when you look at the values. So seems that there are a few things left on the list, based on everyone ideas:
Internal engine related failure
Spark quality (as Rbob hinted along with other member idea's related to spark gap)
Tune related (too much SA?)
Dyno issue (as you hinted)
This one could be paired with: My engine is simply slow and I only thought it was fast when I was younger
Re: Dyno Tuning - Not making real power - EBL Data logs
The spark advance is on the money. 1* pulled per pound of boost, but a lot of guys usually wait to see 5 pounds of boost first before they start pulling, then they will do it in increments of 1* then 2* to help speed it up, but in your case it is fine. It's really hard to say at this point because even Don admitted to being new to SC's earlier, so there might be a problem with the data stream on the dyno because the engine in the youtube videos sounds fine to me, and the data is good. Your best bet would be to do a quick 1/4 mile datalog and let the EBL record it, as in the end, your trap speed never lies. Ever.
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Street Lethal
about 290-RWHP up until that point eventually hitting 300-RWHP if you reached over 5000-RPM
Curious, how do ya know this? Is it a calculation you're performing based on MPH and time?
Originally Posted by Street Lethal
Edit: Bob, look at his g/sec under boost pressure.
What exactly does this value mean?
Originally Posted by Street Lethal
there might be a problem with the dyno stream connection...
Now that you mention it... Kevin, do you know if the problem that we seen with the white car not being read properly on the dyno ended up being a problem with the actual dyno? Sort of doubt the dyno was having issues considering the butt dyno is also telling us basically the same thing we were seeing in the graphs.
Btw, you probably know this, but seems your EBL WUD config. isn't reading my WB AFR values correctly.
Last edited by Napster134; Aug 17, 2018 at 08:01 PM.
Re: Dyno Tuning - Not making real power - EBL Data logs
Nap, regardless of the fuel injection system being used, it only takes a certain amount of air/fuel and weight to run a number, and from there we can calculate your horsepower. We can also calculate your horsepower based on injector duty cycle knowing their flow. The EBL configuration was just a quick analysis because I normally use the P4 WUD version, and I mainly wanted to verify duty cycle, as well as RPM rate of acceleration, that's why the WB data was only showing 10.0 throughout in that caption. I mention data stream because the dyno is showing your naturally aspirated numbers, but then the data gets skewed. Same thing happens when using a 1 Bar MAP when boost is suddenly realized, the data gets skewed. But yes, I would run a quick 1/4 mile analysis with the WUD...
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Street Lethal
I mention data stream because the dyno is showing your naturally aspirated numbers, but then the data gets skewed. Same thing happens when using a 1 Bar MAP when boost is suddenly realized, the data gets skewed.
I don't really understand this. I thought the dyno didn't care about whether my car is N/A or boosted?
I thought the dyno just recorded the amount of power it see's based on how fast & at what acceleration the wheels spin the roller the wheels sit on? (or at least something related to this...)
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Napster134
I don't really understand this. I thought the dyno didn't care about whether my car is N/A or boosted? I thought the dyno just recorded the amount of power it see's based on how fast & at what acceleration the wheels spin the roller the wheels sit on? (or at least something related to this...)
The wheel dyno measures torque and calculates horsepower based on resistance, this is why it differs (lower numbers) from an engine dyno w/out any resistance, or even a desktop dyno, but all use data that is loaded beforehand to help derive to a final number...
- Rob
Edit: Run a quick 1/4 mile blast with the EBL recording. You should see roughly a low 13 second ET trapping at approximately 102-mph. This is what 300-RWHP at 5-psi of boost will net you over your 14.33 run naturally aspirated...
Last edited by Street Lethal; Aug 17, 2018 at 08:49 PM.
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Napster134
That all makes sense... here's the thing...
This may all be in my head... But, my car was fast at one point. Or at the least: It felt fast... much faster than it feels today.
The night I ran 14.33, I don't believe it had even been tuned via a WB yet
I found the 2 wires connector between the distributor & coil was fried. This was replaced and most of the popping went away
The first pass DynoDon went WOT, he immediately asked me "How does the car feel when you actually drive it?"
Anyhow, this is all based on feeling, as for the facts:
We see what you see too: Decent values across the board. Nothing seems too out of the ordinary when you look at the values. So seems that there are a few things left on the list, based on everyone ideas:
Internal engine related failure
Spark quality (as Rbob hinted along with other member idea's related to spark gap)
EBL is showing 90% Duty Cycle at 4300-RPM and you let off immediately after, about 290-RWHP up until that point eventually hitting 300-RWHP if you reached over 5000-RPM, possibly a tad more if you bring it closer to 6000-RPM at 5 pounds of boost pressure. So, the fueling is there, and if the WB is accurate on the dyno as well as in your system, then there might be a problem with the dyno stream connection...
ok ask yourself why did the distributor wiring fry? What happened there? This is a sign of ignition issues. The fact that you are commanding fuel and power is not being made is exactly a lack of ignition problem
Also being that old, how are the valve springs? Potential for floating is there as well but first ignition
plug gap will help alotbut you still may have issues with distributor and coil etc. make sure spark is not arcing. Cracked cap could do that. Check ign module to make sure its ok. Might want to replace if you havent
Re: Dyno Tuning - Not making real power - EBL Data logs
I built a supercharged motor with a very lumpy cam in it and it made horrible power when I added the supercharger. I'm thinking it blew the boost out of the exhaust.... I said let me try it..
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Napster134
Now that you mention it... Kevin, do you know if the problem that we seen with the white car not being read properly on the dyno ended up being a problem with the actual dyno? Sort of doubt the dyno was having issues considering the butt dyno is also telling us basically the same thing we were seeing in the graphs.
No, it was a problem with the white car's spark plug wires. The RPM pickup was not working with them for some reason.
From looking at the RPM's though, it still seems like the RPM's are breaking up a bit. However, there was some knock counts that we didn't see at the dyno (back roads were not perfectly smooth)
Based on feeling: It feels much better. However, need to perform a few runs starting at ~60 MPH. This way, they can be easily compared to the dyno runs as most of them start around that speed.
Re: Dyno Tuning - Not making real power - EBL Data logs
Now that I look at the logs closer/longer, there is quite a bit of knock that was detected. At some points, almost ~6 degrees removed.
When I compare to the dyno day, there was much less knock (almost none)
Re: Dyno Tuning - Not making real power - EBL Data logs
Remember street and tracks will load harder than a dynojet. The timing and even fueling that makes best power on the dyno may not work on the street and track. May need less timing and more fuel
Re: Dyno Tuning - Not making real power - EBL Data logs
Originally Posted by Napster134
Now that I look at the logs closer/longer, there is quite a bit of knock that was detected. At some points, almost ~6 degrees removed.
When I compare to the dyno day, there was much less knock (almost none)
I have the BLH knock filter (ESC module)
From your previous datalogs you have way too much timing. IIRC you were seeing 26-28* of timing. You need to reduce that to 16* under boost and slowly work at bringing in more timing. I also noticed that something was up with your air/flow calculations. There is no way that a 355 engine with decent heads and boost on it should be calculating out at under 100 gms/sec airflow at 4,000 rpm. You need to stop beating on this engine until you figure out the tuning. First verify the displacement scaler for proper engine displacement. Then verify your BPWC is correct for the engine size and injector size as well as the fuel pressure. Once that is accomplished you can adjust the VE tables to correct the fueling. Keep it out of boost until you correct the timing and get the fuel on the rich side before you burn holes in pistons.
