I took the Speed3 out for a longer test drive and a highway run yesterday after putting the cat-back exhaust in. I have a SRI with turbo inlet pipe as well. I know this motor can run into fuel starvation issues with too many bolt on's and at some point the HPFP internals need to be upgraded.

I thought I noticed slight hesitation at 3000 and 4500 rpm under full throttle acceleration. My first thought is that I'm getting a fuel pressure drop on the OEM pump.

Any advice on if this is the most likely issue? No backfiring, no rattle, no knock, just slight hesitation. Ideally if there was an OPPO in the Edmonton area with an Cobb AP that would let me read fuel trim levels that would be best case scenario.

If this is the issue, do you think increasing the flow rate with better HPFP internals will correct the issue? If so, which do you guys recommend? I know there are several MZR engine aficionados out there.

The Autotech ones (I hear) are pretty highly rated. I know CS has been working on some as well, just don't really want to wait long. If it is the fuel pump not able to keep up, I want to correct this now.

Any and all advice is greatly appreciated. Here is a P-38 Lightning for your troubles.

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