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Discussion Starter #1
im bout to buy my girl a 94 civic lx automatic sedan(d15b7, i believe?) and was wondering if/how i can get better gas mileage out of it...obviously maintanance.....but im wondering about the d15z1 longblock in that chasis, or just the head/ecu(if possible) ok, sry for rambling my question is, can i just swap the z1 head onto the b7 block? using the z1 ecu? or will the c/r be too high? also, would the b7 or a z6 IM be a good idea on that head, or the stock z1 IM? i just want to make her lx vtec-e as simply as possible, maybe with a b7/z6 IM/tb, cheap-o intake,cheap-o header and 2" exhaust

someone plz tell me what all i am going to need for the PLEASE!
 

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the head one the b7 block will ahve very high compression and runs like total crap unless u have a chiped ecu and a custom map.. i know from experience and it wouldnt get u much mpg just more power which = less mpg.

if u want the motor basically do the complete z1 swap

otherwise u should be at like what 30+mpg just stock on the b7 if its tuned up and maintained which beats most cars now adays
 

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OMG TOTALLY COOL TITLE!!!!
88 y49 crx
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if you want the gas mileage of the z1 then swap the full setup of the z1 or you wont get the potential of it. and as for more power means less mpg usually yes but bone and his b7 setup that everyone is trying to imitate got him more power and 53mpg
 

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I kid you not, my b15b7 was pulling 40-43 mpg before I changed the timing belt and did a major tune up. I am now getting a *normal* 32 mpg average. I changed the timing belt because the tensioner wasn't keeping tension and the belt was flapping like a flag in the wind. I tried advancing the distributor a couple degrees (twice) but to no avail. That motors pretty stout and economical. From that stand point alone, assuming it runs good and all other things equal, I wouldn't mess with it.
 

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The car will be slow as balls, Dont do it. It was made for an incredibly light chassis, and let me tell you, from personal experience, even then it was slow.

Also the z1 has an incredibly long geared tranny, so if you plan to stay with the auto, its adding insult to injury.

Keep the B7 and dont drive it like you stole it and you will get 40mpg.

If your up for a manual swap, you can pick up a few more.
 

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Discussion Starter #6
well ive got an ej1 with a jdm sohc zc vtec(z6) and get about 35 mpg, which is enuf for me and not too shabby powerwise, but im about to buy my gurl a matchin sedan and would like her car to get like 45+ mpg so theres no way of swappin on the head and ecu onto the b7 block and getn good mpg? now IF i did do the full z1 swap, would it be straight forward as my jdm swap in my ej1, or is there more into it being that its an "oddball" vtec-e engine? also, with a z1 in the car, would a cheapo SRI, b7 or z6 IM/TB, cheap-o header and small 2" exhaust make mileage worse, or could it help mileage?(with all the z1 fuel components,,,i.e. fuel rail, injectors,ecu...) i want my car to have ballz, and hers to be great on gas.....how can i make her lx sedan have d15z1-ish gas mileage?
 

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Let me put it this way. The more pedal she has to give the car, the worse MPG it will actually get. This is why its not a good idea to put a tiny engine in a big car. This is also why bolt ons tend to increase perceived MPG, because you need less pedal to achieve the same acceleration.

Seriously dude, take the B7, do a manual swap, and get an MPG tune like I got. It will get 45+ and not be stupid slow.
 

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i was told the z1 was'nt built for an automatic so the ecu wont work and also if you do the z1 swap you will have to add egr stuff and 5 wire o2 and still will be slow i have a 93 coupe that i bought cheep and it came with a z1 in it and it is the biggest turd out there it got smoked by geo metro so i could only imagine it in a 4 door
 

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Get a wideband and tune that sucker! I promise, my Z6 with a crower stage 2 cam has been making at least 40 mpg since I got it to quit running pig rich, with a best of 47 mpg...All this with an Si tranny, albeit in a 90 crx si...But still, you could benefit a lot from driving easy and a good tune on it. I wanna say transzex made like 53 mpg on a b7 in an eg.
 

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yes, but Automatic B7's suck balls.

ONLY reason to consider a Z1 head would be the bump in compression, but then the engine would be choked by the intake ports assuming you locked in the seconday intake valve.

Compression ratio would be 12.5:1, with a no performance cam profile this would be a bad idea.
 
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