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Discussion Starter #1
I plan on using a microsquirt on my TT BBF jet boat project that I have been collecting parts for. My set up is raw water cooled (running NA carburetor now) with a simple valve between the jet pump and engine that I adjust for engine out water temp. I usually restrict it until I get to 180*F on an extended idle after running the boat on plane for awhile....then as RPM/load increases for running on plane the engine out water temp will drop to 130*F to 110 *F depending on how hard I run the boat.

This of course leads to an issue will closed loop operation...warm up enrichment...and start up enrichment...

My thought is to put a bung in the oil pan or to make a large Tee for the turbo oil lines and measure engine oil temp directly as I would coolant temp...this would be a better indicator of actual "engine temp" for this application and I can change the temperature conditions in the tables so the features work properly..

Any thoughts? What have you guys run with success?
 

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I plan on using a microsquirt on my TT BBF jet boat project that I have been collecting parts for. My set up is raw water cooled (running NA carburetor now) with a simple valve between the jet pump and engine that I adjust for engine out water temp. I usually restrict it until I get to 180*F on an extended idle after running the boat on plane for awhile....then as RPM/load increases for running on plane the engine out water temp will drop to 130*F to 110 *F depending on how hard I run the boat.

This of course leads to an issue will closed loop operation...warm up enrichment...and start up enrichment...

My thought is to put a bung in the oil pan or to make a large Tee for the turbo oil lines and measure engine oil temp directly as I would coolant temp...this would be a better indicator of actual "engine temp" for this application and I can change the temperature conditions in the tables so the features work properly..

Any thoughts? What have you guys run with success?
You don't want your water temp at 180 degrees. You want hot oil temps 190-220. Water temp 110-130.
 

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Discussion Starter #3
Ok...noted....I do run in the cooler range when the boat is on plane

I know some guys have experience tuning EFI on a jet boat....just curious how you account for the cooler engine temp (water) for your Warm Up Enrichment and Start Up Enrichment
 

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Having consistent water temps will help make you more power if you machine for it. Oil temp plays a small role in expansion and contraction of engine components. Engines don't make more power cold, they are more efficient with higher temps..... closer tolerances, better atomization, etc. Cold engines have fuel separation issues, so running a thermostat makes sense. The issue is doing it on a BBF. I've had a few of these setups on my 460's and they consistently run 175* with a 180 thermostat. I've seen a couple in the classifieds, and seem to recall Hardin made them back in the day. Keep an eye out, it's worth the investment.
Here's setup on the 545 I'm building for the tugboat.
 

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