February 26, 2010 - That's starting to look like a race engine.
It took a fair bit of work to get to this point - I spent all day Wednesday as well as a couple of hours on Thursday and Friday - but I've added at least 50 visual horsepower.
The biggest problem was a fuel rail that had holes 10.50mm in diameter. The stock Miata rail is 11.00mm. I couldn't get the injectors to seat without tearing an o-ring. I tried various o-rings from the shelves at Flyin' Miata, but all they had were stock or oversize. A trip to NAPA yielded the perfect thing - injector seals from a Geo Metro! Kudos to the NAPA counter guy who nailed them on the first try.
The red lines are running to a mount for the idle speed control valve. This gives the throttle bodies a bit more civility than you often find with this sort of setup. The ones on the Seven don't have this, and I have to keep that car alive with the throttle until the engine warms up. Not here!
I haven't had it on the dyno yet, I'm hoping to do that this weekend. On a short test drive, the car ran very rich on partial throttle, but felt very good wide open. I'll sort that out in the Hydra programming. It makes a very characteristic noise, with a distinct growl for each cylinder. The return springs on the throttles are pretty stiff so that will take some practice when matching revs - but overall, considering the amount of work to install, it behaved pretty well.
I'm looking forward to see what this has (or hasn't) done to the power output.
tags: intake, testing |
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