You can seal DISA radially also. I use special Teflon tape that changes color under pressure so a couple test fits will determine if I have enough.

The starting fluid test is good to find vacuum leaks but I've heard best to use propane (won't drip into places that can cause a problem). Also, watch your O2 sensor reading real-time and you get a much more sensitive feedback vs. listen for RPM.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)