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The BEST Ever H6 Swap Thread

678K views 2.7K replies 236 participants last post by  sharpman993  
Unfortunately I don't think anyone from this thread is still actively pursuing the ez30r swap, tho not for a lack of trying.

I'd love to have one swapped into something I own. However, on top of the custom work & wiring, it sounds like the tuning would be formidable as well. You should ask a tuner you trust what ecu he is comfortable with. I'm sure there's a Haltech that will work. Matter of fact, I know there is, because that's what the "Mighty Car Mods" guys are using.

Here's a quote from a tuner, about 100 pages into one of the H6 swap threads on Nasioc:



My takeaway was since there probably won't be any basemaps (for the Hydra standalone in that example, but it should hold true for others as well, unless maybe Haltech spent the time "scoping out" all the sensors on that engine, then developed a basemap?) It will cost $$$ just to get the engine started. Even more getting it tuned.


Regarding your other question about throttle bodies, I couldn't find anything about it. It will probably mean you'll have to make a spacer plate to adapt it.


I don't want to sound all negative about this engine, but there are probably 1000 pages of people asking questions and working on this swap (across the whole internet) with almost no success stories.

What about the ez30r's dumber cousin, the ez30d, with a simplier standalone? Throw a centrifugal supercharger on there with a basic standalone, pay a tuner or learn how to tune, and hopefully have fun?
Thank you for your answer. The good news is that Haltech now has fully support for the engine + a base map and a good resource page: https://support.haltech.com/portal/en/kb/articles/ez30-engine

I recently saw this and was thinking that it might be worth the Haltech premium to have all of this you explain sorted out. I mean, what is 500 extra compared to all the headache and time to figure it out myself. I will probably save that money anyway because of the base map. I think the easiest route to go would be to run dual ECU - keep my GC8 ECU for all things not engine related and just use a cut EZ30 harness wired to the Haltech to manage the engine. This car will be a track car anyway so no need to be road legal. Going that route I won't end up with the harness merge hell. My friend used this dual ECU approach when he did his EJ207 + standalone swap, works great.

The EZ30d would be simpler (and cheaper due to standalone requirements), but my plan is to do a high rev N/A build with built/ported heads so EZ30R is the way to go.