Stock ECU - Dyno results - questions
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Many subjects will have been discussed before. Please try the search function before starting a new thread.
Check in the Know Your 2 as the information you need may already be there.
Important ! - Please make your topic title as descriptive as possible . titles with just "help" generally dont get as many answers as a title that points to the problem
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Topic author - Posts: 60
- Joined: 22/11/19 18:20
Stock ECU - Dyno results - questions
Hi all,
Had my rev3 turbo on the dyno today.
Mods: st205 charge cooler, decat downpipe and exhaust, mbc at 16psi. Stock ecu.
Happy with the 280bhp but 245 lbs of torque seems a bit low compared to other graphs I’ve seen. The shape of the power curve is very nice though.
Questions:
Could the low torque maybe be down to the lean spot in the AFR as the boost comes on as seen below?
Ive been told this lean spot happens with all stock ECUs?
Should I be concerned with this AFR curve? The car is used mainly as a track car so I want to make sure it doesn’t go bang and the AFR is all correct. The chap at the dyno said it is not ideal, but there was no knocking. What do you guys think?
Looks like I would really benefit from an after market ECU to map out the Lean spot.
Had my rev3 turbo on the dyno today.
Mods: st205 charge cooler, decat downpipe and exhaust, mbc at 16psi. Stock ecu.
Happy with the 280bhp but 245 lbs of torque seems a bit low compared to other graphs I’ve seen. The shape of the power curve is very nice though.
Questions:
Could the low torque maybe be down to the lean spot in the AFR as the boost comes on as seen below?
Ive been told this lean spot happens with all stock ECUs?
Should I be concerned with this AFR curve? The car is used mainly as a track car so I want to make sure it doesn’t go bang and the AFR is all correct. The chap at the dyno said it is not ideal, but there was no knocking. What do you guys think?
Looks like I would really benefit from an after market ECU to map out the Lean spot.
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Topic author - Posts: 60
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Re: Stock ECU - Dyno results - questions
Also I should add, I have already done 1 track day with the car and the engine was faultless. Intake temps were kept low and it felt and sounded like it was running perfectly.
Just want to know if that lean spot is dangerous and needs to be corrected before I track the car again
Just want to know if that lean spot is dangerous and needs to be corrected before I track the car again
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Re: Stock ECU - Dyno results - questions
where is the boost pressure vs AFR graph ?
I presume the test is a third gear run and that's power at the engine ?
Yes it's down on torque compared to my Rev 1 mine is 270 from memory.
Graph looks pretty normal to me that's just a blip before it turn very rich at higher rpms. More power would come from more boost and watch that curve flatten out from 4500rpm on a stock ECU.
I presume the test is a third gear run and that's power at the engine ?
Yes it's down on torque compared to my Rev 1 mine is 270 from memory.
Graph looks pretty normal to me that's just a blip before it turn very rich at higher rpms. More power would come from more boost and watch that curve flatten out from 4500rpm on a stock ECU.
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Topic author - Posts: 60
- Joined: 22/11/19 18:20
Re: Stock ECU - Dyno results - questions
I didn’t get a boost pressure graph for some reason but from my gauge, it is peaking at 16psi and want to leave some room for colder weather so it doesn’t hit fuel cut. I’m pretty happy with the power, and as its a track car the lower torque doesn’t matter as much.
Just wanted to see people’s opinions on if that AFR curve would be dangerous. And sounds like you don’t think there’s much cause for concern.
Car ran perfectly on track so think I will just leave as is.
Thanks
Just wanted to see people’s opinions on if that AFR curve would be dangerous. And sounds like you don’t think there’s much cause for concern.
Car ran perfectly on track so think I will just leave as is.
Thanks
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Re: Stock ECU - Dyno results - questions
The boost pressure/AFR graph is really needed to ascertain if its a potential problem or not. If you're piling in 16psi at that point then thats a bit of a concern. If its only getting to 16psi at 4500RPM+ where the AFR's are much safer, you're fine.
Rev5 Sonic Shadow
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Re: Stock ECU - Dyno results - questions
Your ECU seems to move from Closed to Open loop really late.
3800rpm and a certain amount of boost detected should force the ECU to take over from the O2 sensor for your AFR... The fact its not dropping until just after 4000rpm is concerning if you ask me...
Along with that Lean spike! I would personally check 2 things...
If your injectors are Lazy / need replacing or your alternator slipped at that point and dropped voltage which can in some cases cause fuel issues for that small amount of time.
Hope you get to the bottom of this however!
3800rpm and a certain amount of boost detected should force the ECU to take over from the O2 sensor for your AFR... The fact its not dropping until just after 4000rpm is concerning if you ask me...
Along with that Lean spike! I would personally check 2 things...
If your injectors are Lazy / need replacing or your alternator slipped at that point and dropped voltage which can in some cases cause fuel issues for that small amount of time.
Hope you get to the bottom of this however!
I can't figure out how to put in an image here, so this is my cry for help.
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Re: Stock ECU - Dyno results - questions
IMO
The chances of that happening are extremely unlikely, the alternator would have to virtually stop and the battery be extremely poor for the system voltage to drop low enough in that very short time to have any effect on the fueling
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Re: Stock ECU - Dyno results - questions
You are correct, i have read on other forums that fuel can be effected by a sudden change in voltage.
Unlikely i agree but not entirely unheard of.
Lazy injectors or something up with the ECU switching to Open loop would be my guess?
Unlikely i agree but not entirely unheard of.
Lazy injectors or something up with the ECU switching to Open loop would be my guess?
I can't figure out how to put in an image here, so this is my cry for help.
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Topic author - Posts: 60
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Re: Stock ECU - Dyno results - questions
That’s very interesting, thanks
I think I am going to take the plunge and go for a stand-alone ECU.
I assume this lean spot could be mapped out? Assuming I get the injectors checked and are ok.
What other benefits of a new ecu are there? Could I get rid of my manual boost controller if I get an ecu with built in boost control? Not sure how that works.
And do you think I would see power and more importantly torque gains?
I would like to increase the torque more than anything. 245 seems low:(
I think I am going to take the plunge and go for a stand-alone ECU.
I assume this lean spot could be mapped out? Assuming I get the injectors checked and are ok.
What other benefits of a new ecu are there? Could I get rid of my manual boost controller if I get an ecu with built in boost control? Not sure how that works.
And do you think I would see power and more importantly torque gains?
I would like to increase the torque more than anything. 245 seems low:(
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Topic author - Posts: 60
- Joined: 22/11/19 18:20
Re: Stock ECU - Dyno results - questions
Seem strange the ecu would be going into open loop later than usual though.
Maybe it does point to lazy injectors instead.
Do you think an aftermarket ecu would be a good move for me given the issues shown?
Maybe it does point to lazy injectors instead.
Do you think an aftermarket ecu would be a good move for me given the issues shown?
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Re: Stock ECU - Dyno results - questions
The only bad thing i see in there is that lean spike at 3800-3900rpm that then drops down.
It's like your open loop spikes lean then goes "oh "censored"" and then drops drastically. Maybe pulling the EFI Fuse for 10 min and let the fuel maps stored in the ecu have a "relearn"?
Standalone should sort it out, so long as no physical problem is there such as injectors, o2 sensors.
Hope you manage to sort it out, Mine is up for a dyno run tomorrow, so hoping mine is all good
It's like your open loop spikes lean then goes "oh "censored"" and then drops drastically. Maybe pulling the EFI Fuse for 10 min and let the fuel maps stored in the ecu have a "relearn"?
Standalone should sort it out, so long as no physical problem is there such as injectors, o2 sensors.
Hope you manage to sort it out, Mine is up for a dyno run tomorrow, so hoping mine is all good
I can't figure out how to put in an image here, so this is my cry for help.