The latest update to the Forum Build Thread for our 2015 Mustang Trigger is a huge 5 part entry. In that we cover work from June through August 2023 – where a LOT of upgrades, testing, an autocross, and finally some actual Time Trial competition – and even the car’s first win. That build thread also covers other work we’ve done on other S550 Mustangs, and even the work on our S650 Darkhorse.
With the massive 112mm throttle body the “throttle response” was absolutely brutal, and keeping the car pointed straight when tipping into or out of the power was a delicate dance. It was costing us a LOT of time on track so we made some drastic changes – removing the BTR Trinity intake and 112 TB and going to a “known quantity” MSD Atomic and 103mm TB. the smaller TB would choke off power but it should also make the car much easier to drive.
That intake swap fixed a lot of the drivability issues (and lost all of 7 hp), but we were fighting a low oil pressure situation after long left hand turns on track – and when pressure would dip below 38 psi a safety protocol in the tune would trigger a sort of rev limiter until oil pressure returned. We fought this issue for 2 months (and with as bad as the Holley data is, it was hard to even pinpoint the cause for a few events) and tried a lot of fixes to the GM LS7 based “Dry sump” oil system (we fixed it later by going to an external 4 stage dry sump pump and new pan).
We cover dozens of worthwhile updates in this 5 part Forum Post, like this driver cooling system from dfuser.com. That helped get us through those hot summer Time Trial events! But we fought major issues with Holley EFI and dash, an Optima battery, and more. We show hundreds of pictures and over a dozen videos in the coverage this time.
This couple of months of work on Trigger were INTENSE in the shop, with our shop manager Brad doing all of the work, but also working with engineering team, outside tuners, and everyone who worked at the track with this car. It might seem like I was a little frustrated when writing this five part Forum entry, just know that LIVING these months of struggle was much worse!
Hopefully some of you can learn from our mistakes and tests of new products from this difficult stint on this project. The next forum update will cover more fun things and a HUGE improvement in oil pressure, downforce (see above), and a major drop in lap times. I’m actually looking forward to writing the next entry – that’s when this car started REALLY kicking ass! Thanks for reading the coverage, even these un-fun parts, and hopefully we will see you at the track more in 2024!