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owendavidj · 02-11-2015, 04:18 AM

I currently have a 88 civic hatch dx, with stock d15 motor.
Summer driving gets me a steady tank after tank of 45mpg.
Winter driving obviously varies dramatically, anywhere from 30-40mpg avg/tank.

Well the previous owner didn't take care of my baby like i do most cars, and I'm burning oil faster than a lantern. Is time for new internals. I call my mechanic, explain my desires and also asked how much to shave the head slightly, and possibly find some higher compression pistons. He calls me back 2 hours later with options and pricing.

1 first option is a full rebuild of existing motor, replacing most parts and machining/polishing the rest. He did he'd also shave my had for very slight compression gains. Unfortunately there are no mods available for this older d15 without some serious expensive custom work. But he assured me when he's finished the engine would be BETTER than band new.

2 he happens to have a d16 Vtec motor from a 94 civic on hand. This motor has been rebuilt (but not quite machined/polished/tuned to the extent he would perform on my old d15). This wasn't an economy motor, as it's got about 135hp he claims. Vs. my old motor, this is multi point injection and also vtec. But this motor has mods-a-plenty, as one of Hondas more popular engines, and I'll admit that little extra hp would feel nice on step long freeway hills in the mountains that are oh so aggravating... This will match up to my old transmission fine, and i believe he did we can keep my old smaller alternator as well.

So...dilemma:

Obviously the rebuild on my old motor is going to be a great eco boost for me, no questions about that, but probably not going to help in the getting up steep mountain freeways dept.

What is your guys experience with the d16? My worry is that the swap for the new motor may leave me with WORSE mileage than my current beater. My mechanic points out that if i stay "under vtec" keeping the rpms low (which i drove this way anyway), and since I'll now have the more efficient multi point injection he thinks my mileage might stay the same. And he also points out that the options are virtually limitless with this motor, as opposed to no custom options with the old. (crankshaft, pistons, bolt on mods, etc etc etc).

The kicker: both jobs are quoted at $2k. The swap actually being slightly cheaper.

Sorry i don't have specifics on the EXACT motor, but this would be an (aprox) 135hp Vtec d16 from a 94 civic.....who has had real-world mpg existence with this motor? What do you guys think?

02-11-2015, 04:18 AM	#1 (permalink)
owendavidj EcoModding Lurker Join Date: Feb 2015 Location: Taylors sc Posts: 7 Thanks: 0 Thanked 0 Times in 0 Posts	Honda motor swap, opinions? I currently have a 88 civic hatch dx, with stock d15 motor. Summer driving gets me a steady tank after tank of 45mpg. Winter driving obviously varies dramatically, anywhere from 30-40mpg avg/tank. Well the previous owner didn't take care of my baby like i do most cars, and I'm burning oil faster than a lantern. Is time for new internals. I call my mechanic, explain my desires and also asked how much to shave the head slightly, and possibly find some higher compression pistons. He calls me back 2 hours later with options and pricing. 1 first option is a full rebuild of existing motor, replacing most parts and machining/polishing the rest. He did he'd also shave my had for very slight compression gains. Unfortunately there are no mods available for this older d15 without some serious expensive custom work. But he assured me when he's finished the engine would be BETTER than band new. 2 he happens to have a d16 Vtec motor from a 94 civic on hand. This motor has been rebuilt (but not quite machined/polished/tuned to the extent he would perform on my old d15). This wasn't an economy motor, as it's got about 135hp he claims. Vs. my old motor, this is multi point injection and also vtec. But this motor has mods-a-plenty, as one of Hondas more popular engines, and I'll admit that little extra hp would feel nice on step long freeway hills in the mountains that are oh so aggravating... This will match up to my old transmission fine, and i believe he did we can keep my old smaller alternator as well. So...dilemma: Obviously the rebuild on my old motor is going to be a great eco boost for me, no questions about that, but probably not going to help in the getting up steep mountain freeways dept. What is your guys experience with the d16? My worry is that the swap for the new motor may leave me with WORSE mileage than my current beater. My mechanic points out that if i stay "under vtec" keeping the rpms low (which i drove this way anyway), and since I'll now have the more efficient multi point injection he thinks my mileage might stay the same. And he also points out that the options are virtually limitless with this motor, as opposed to no custom options with the old. (crankshaft, pistons, bolt on mods, etc etc etc). The kicker: both jobs are quoted at $2k. The swap actually being slightly cheaper. Sorry i don't have specifics on the EXACT motor, but this would be an (aprox) 135hp Vtec d16 from a 94 civic.....who has had real-world mpg existence with this motor? What do you guys think?