Twist1
Autocross Newbie
- Location
- Breaking Mustang Hearts
So we have started tuning this new build in the last week. The TBB v2 was on for a couple weeks and then 980cc cts mpi and 525 lpfp was enabled and we got to tuning. After some LPFP weirdness all was well and we got to ripping.
Then all of a sudden we start pushing power to the left and we get ALL this knock. Tried to soften, more knock, more knock, more knock. It's knocking with less timing and HIGHER octane than it was before.
Something is going on...
One of my close buddies just did the same build to his s3 and left these plates pictured out on accident. He mentioned he thought they were impacting the way mpi injectors flowed into the cylinder. So I asked a couple on here that have made 500+ in oem motors and both left theirs in, so I figured they probably were fine to leave in and helped with stabilizing airflow coming into the cylinder.
WRONG.
I left mine in and the injectors were literally spraying straight on them. Pull out the mpi and look down the holes. They are literally spraying directly onto them and then splattering everywhere.
It's clean beneath 500~whp, as more fuel is more fuel and our DI still does a lot. However once we really started to get above 500 the spray was just not getting into the cylinder.
This is after MPI enabled for one week. There was blowby nearly all up the injector and gas all the way up to the seals. Does anyone k ow more about this? What do euro cars look like in the head?
To also help fix this I took my injector clips off so they could be seated all the way down. I'm sure those chickens will come home to roost but for now, all's well.
Then all of a sudden we start pushing power to the left and we get ALL this knock. Tried to soften, more knock, more knock, more knock. It's knocking with less timing and HIGHER octane than it was before.
Something is going on...
One of my close buddies just did the same build to his s3 and left these plates pictured out on accident. He mentioned he thought they were impacting the way mpi injectors flowed into the cylinder. So I asked a couple on here that have made 500+ in oem motors and both left theirs in, so I figured they probably were fine to leave in and helped with stabilizing airflow coming into the cylinder.
WRONG.
I left mine in and the injectors were literally spraying straight on them. Pull out the mpi and look down the holes. They are literally spraying directly onto them and then splattering everywhere.
It's clean beneath 500~whp, as more fuel is more fuel and our DI still does a lot. However once we really started to get above 500 the spray was just not getting into the cylinder.
This is after MPI enabled for one week. There was blowby nearly all up the injector and gas all the way up to the seals. Does anyone k ow more about this? What do euro cars look like in the head?
To also help fix this I took my injector clips off so they could be seated all the way down. I'm sure those chickens will come home to roost but for now, all's well.
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