Honda Fuel Injector and throttle body Size/Swap

[kwtorbe]

I have a '97 Civic HX. I was wondering what size the injectors and throttle body are? Do the 1.5L engines such as cx or vx have smaller injectors and/or throttle bodies. I know it is better to run a engine rich for dependability, but could I install smaller injectors and throttle body from another honda, like the performace guys install larger injectors and throttle bodies, to achieve better FE?

Thanks,

Kent

P.S. I just got a CX tranny and will be doing the swap soon!

[rh77]

Originally Posted by kwtorbe

I have a '97 Civic HX. I was wondering what size the injectors and throttle body are? Do the 1.5L engines such as cx or vx have smaller injectors and/or throttle bodies. I know it is better to run a engine rich for dependability, but could I install smaller injectors and throttle body from another honda, like the performace guys install larger injectors and throttle bodies, to achieve better FE?

Thanks,

Kent

P.S. I just got a CX tranny and will be doing the swap soon!

You'd probably have to change out the ECU as it'll expect more fuel for the oxygen sensor and dump-in extra fuel to compensate. An EFIE with wide-band O2 Sensor, or programmable ECU definitely would be a nice addition.

[kwtorbe]

Thanks, Also, will a d15b8 intake bolt on to my d16y5? I know the b8 is an 8 valve and the y5 is 16 valve but will it still bolt?

[SVOboy]

The intake will fit, but won't be such a good idea because the ports will not match the head...the y5 manifold is what you should stick with. You prolly have a 56mm TB and would not be able to swap it out for a cx, vx, or hf. Your intake/injector set up is about the best non-custom you can get for your engine.

[kwtorbe]

oh. Would you swap in a complete d15b8 from a CX? Or maybe a mini-me HX head swap onto the 1.5L? I drive like a granny and can only get 45 mpg. I want the 55 mpg of the CX or VX.... I don't care about high end power at all.

[cems70]

kwtorbe:

My wife has a '98 HX that we bought used 2 yeears ago w/ 52k miles on it. She commutes 86 miles roundtrip each day, 95% highway. Sometimes it turns into city driving w/ some stop and go rush hour traffic. She drives 70 mph. The tires are crappy BF Goodrich that don't seem to be LRR, and they aren't even high pressure tires (only 36 psi max). She regularly gets 46 - 48.5 mpg during the summer, 43 - 46 mpg during the spring/fall, and 40 - 43 mpg during the winter. I recently did a front grille block, and I'm dying for the tires to wear out so I can replace them w/ a set of Sumitomo HTR T4 ("excellent" LRR rating in Consumer Reports test). I'll bet she breaks 50 mpg during the summer, and would probably get 52 - 53 mpg if she drove 55 - 60 mph.

The CX/VX tranny is not geared significantly taller than the HX tranny. You think you'll really improve your FE that much? I'm going to swap my '95 DX hatchback tranny for a CX/VX tranny because there's a big difference in gearing. But even w/ that big gearing difference between DX and CX/VX, another member who did the same swap only saw about a 6% increase in FE. My guess is you won't get more than a 2 - 3% increase w/ your swap.

Given what I said about my wife's HX, I'm surprised you're only managing 45 mpg driving like a granny.

Steve

[kwtorbe]

Not only do I drive like a granny (never over 65), I also drive mainly highway and kill it coming to stop lights and coast a ton. Tires are 44 psi but not LRR. I have a grille block, a WAI, and 195 F thermostat. I don't think my lean burn works right but I don't want to pony up for a new O2 sensor. Are you sure there isn't much of a difference between HX and CX/VX transmissions? I think HX, DX, LX are all the same gearing...Oh yeah, I have over 200,000 on original drive train too.

[SVOboy]

If you want to swap I would go for the vx engine, if you get a crate engine like matt did it'll only run you 550 (only...). But yeah, the swap would be nice, it depends on how much you can do yourself though for the cost.

[kwtorbe]

My dad and I completely rebuild muscle cars (other than machine work). A vx swap would be easy for me if I find an engine cheap enough....

[kwtorbe]

So a d15b8 swap or parts swap wouldn't improve my efficiency..... I kindoff got one with my cx tranny.