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Old 01-28-2010, 02:10 PM   #8 (permalink)
90crxHF
Si engine and trans
 
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Join Date: Jan 2010
Location: Spring, Tx
Posts: 53

CRX Si/HF - '90 Honda CRX HF
90 day: 40.35 mpg (US)
Thanks: 3
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Quote:
Originally Posted by Wonderboy View Post
Ah, another ecomodder stuck with a ricey engine. I have to deal with a torquey 98 Civic EX coupe that makes 127HP... Your motor makes 108 I think, so you have a bit of an easier path but we have the same final drive ratio (4.25) with my 5th gear at .702 and yours at .771. What a bummer that you don't have the original D15B6, or especially that HF transmission.

Looking at my fuel log you would see that the lower 50s MPG is attainable with a more powerful and heavier car than yours, but I never really go 70 unless I'm rolling down a hill. Based on my experience and what I've read, I think your goal is possible, but it's a lofty goal and you will have to make some drastic changes to any or all of the following: your driving style, your engine/trans, aerodynamics, LRR tires. Ditch the CAI and get that engine breathing some hot/warm air right off the exhaust manifold - that should help a bit too.

Personally I'd list it as an Si. That would make you look better as an Si with that lightweight HF body versus making your results look worse among genuine HFs, but more power to you if you can beat them out with your car.

Good luck and welcome to EM!
Thanks for the welcome, and trust me, I know there's much more to do and try and experiment with... I am going to make an entire under car belly pan, and I'm doing it very, very soon. I'm doing more aero mods, and probably getting LRR tires soon as well. I want to do something with the rear of the car now, but I need to read more....

Speaking of warm-air intakes, I removed the coolant lines that used to run through the throttle body and IACV and I simply looped it back to the engine. I should probably hook this back up. Also, I am not running the IACV, due to the fact I could not make the car idle properly without removing it.

So, I should be able to hit 50MPG, cool... I am trying like hell to do it while having a car that run's a very low 15 second 1/4 mile. BTW, I don't know how I ever drove with out the vacuum gauge, I love it!!
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