tune help
Thread Starter
9 Second Club
Joined: Jan 2012
Posts: 126
Likes: 3
From: Post Falls, Id
tune help First off here is my set up:
Stock harness and 411 ecm tuned with HP Tunners
6.0 iron block, forged h beam rods, Arias forged dish pistons , 6.5:1 comp
6.2 truck heads
2010 Zr1 cam
ict billet intake manifold w/ 102mm Tb
78/75 .96ar on3 turbo
80lb Siemens deka high imp injectors that have been flow matched
twin 340 lph intank fuel pumps
44mm wastegate 14lb spring
50mm bov
So my issue is this motor used to be on a blowthru pro systems carb and ran great, it ran 9.20's in the 1/4 on 14lbs of boost . I have now switched to efi ( newbe to EFI) and I cant seem to nail down an issue. So here it is. I can drive down the road and the throttle response is slow.but does improve above 2500 rpm once i am in the boost . it runs good from 0-7lbs but any more than that the motor starts bucking. i can tell you it is not a lack of fuel, i do have a boost ref regulator and a gauge so i can see the regulator is adding fuel pressure to the boost increase, the log shows no decrease in injector flow. timing is between 14-16 deg when this starts happening ( on the blowthru i was running as high as 26 deg under full 14 lb of boost with no det or knock) So my question is do i need to add more timing? or take more out? the thing that baffles me is that the wide band shows around 11.2-11.4 afr and the log doesn't reflect the bucking.Any Ideas on what to look at or try to eliminate this issue? i am attaching my latest log and tune if anyone can look at it and maybe see something I don't.
Stock harness and 411 ecm tuned with HP Tunners
6.0 iron block, forged h beam rods, Arias forged dish pistons , 6.5:1 comp
6.2 truck heads
2010 Zr1 cam
ict billet intake manifold w/ 102mm Tb
78/75 .96ar on3 turbo
80lb Siemens deka high imp injectors that have been flow matched
twin 340 lph intank fuel pumps
44mm wastegate 14lb spring
50mm bov
So my issue is this motor used to be on a blowthru pro systems carb and ran great, it ran 9.20's in the 1/4 on 14lbs of boost . I have now switched to efi ( newbe to EFI) and I cant seem to nail down an issue. So here it is. I can drive down the road and the throttle response is slow.but does improve above 2500 rpm once i am in the boost . it runs good from 0-7lbs but any more than that the motor starts bucking. i can tell you it is not a lack of fuel, i do have a boost ref regulator and a gauge so i can see the regulator is adding fuel pressure to the boost increase, the log shows no decrease in injector flow. timing is between 14-16 deg when this starts happening ( on the blowthru i was running as high as 26 deg under full 14 lb of boost with no det or knock) So my question is do i need to add more timing? or take more out? the thing that baffles me is that the wide band shows around 11.2-11.4 afr and the log doesn't reflect the bucking.Any Ideas on what to look at or try to eliminate this issue? i am attaching my latest log and tune if anyone can look at it and maybe see something I don't.
you are commanding too much fuel at less than 7 psi of boost. On the log there is no wideband feedback, but based on your o2 mv, you have way too much fuel and your injectors are past 100% duty cycle.
EDIT* Your tune file needs tons of work. Your VE is inaccurate, your power enrichment and boost enrichment is ridiculous. You cant even use your spark table properly as you can see by the 3.3 g/cyl values at a measly 140 kpa.
set your boost enrichment to 1.25 from 100 kpa to 200 kpa, then from 200 kpa and on ramp it in from 1.25 to 1.32 . Rework your VE from there. Once again, your issue is TOO much fuel being commanded and assuming your afr readings are accurate, then you are out of injector or pump. Your data has 83 lb injectors so at this point I am deducing your fuel pump is not keeping up or you dont have 83 lb injectors.
EDIT* Your tune file needs tons of work. Your VE is inaccurate, your power enrichment and boost enrichment is ridiculous. You cant even use your spark table properly as you can see by the 3.3 g/cyl values at a measly 140 kpa.
set your boost enrichment to 1.25 from 100 kpa to 200 kpa, then from 200 kpa and on ramp it in from 1.25 to 1.32 . Rework your VE from there. Once again, your issue is TOO much fuel being commanded and assuming your afr readings are accurate, then you are out of injector or pump. Your data has 83 lb injectors so at this point I am deducing your fuel pump is not keeping up or you dont have 83 lb injectors.
Last edited by subeone; Jun 15, 2018 at 01:55 AM.
Thread Starter
9 Second Club
Joined: Jan 2012
Posts: 126
Likes: 3
From: Post Falls, Id
I understand that my settings are all high and out of wack but it wont run off a base tune that i got from a friends car that is very similar in build, the only difference is the Comp ratio. I am attaching that tune so if anybody can tell me why it works on his set up and doesn't allow mine to run that would be helpful, with his tune mine fires then dies right away wont stay running.
or is there anyone out there that has a set up similar to mine that I can copy for a base tune, that would be great. my problem is i am not familiar with hp tuners or efi and i have limited knowledge of the abbreviations of each setting ie: ve, decay, stuff like that. I am just trying to get it to run well enough to drive it to a tuner , which the closest to me is 160 miles away and i don't have a trailer to haul it.
or is there anyone out there that has a set up similar to mine that I can copy for a base tune, that would be great. my problem is i am not familiar with hp tuners or efi and i have limited knowledge of the abbreviations of each setting ie: ve, decay, stuff like that. I am just trying to get it to run well enough to drive it to a tuner , which the closest to me is 160 miles away and i don't have a trailer to haul it.
