Green Street

Not a lot of traffic on this model.

I have a '94 Civic VX with the VTEC-E (D15Z1) engine. I am trying to optimize the car's overall peformance (and looks). Meaning I want to max out the fuel efficiency while also getting the car to run (and look) it's best.

Here comes the questions:
Can this engine run better and possibly add to (but not take away from) the high mpg with...?
o Cam Timing
o Overdrive Pulleys
o Ignition upgrade (NGK iradium plugs, performance wires and coil)

[Other plans include shaving weight from the battery, hood, quarter panels, windows, muffler and exhaust. Muffler and exhaust are also places that I am looking to optimize overall performance.]

Gotta get answers to the three questions above first.

Open for any and all advice and suggestions.

Ricey McRicerton

Try searching for a lightweight battery thread by the HT user Rodney. As far as gains on that motor you have, they will be minimal using the parts you have asked about. The stock Honda ignition is good to upwards of 3-400 hp, and anything aftermarket up until that point is just going to be one more thing that can go wrong. You're best bet is to swap in a D16Z6 (motor from a Civic EX) if you are trying to find some major gains for little money. This Z6 is a SOHC VTEC motor with 125 hp and a much shorter geared transmission. That is the main weakness to the motor/tranny that you have now. Those long gears are going to kill any performance you are trying to acheieve. With that said, a Z6 with bolt ons is not going to be a racecar by any means, but will be quicker, and with some weight reduction and good driving you should be able to hit a low 15 second 1/4 mile time fairly easy. As far as waht to do with your motor, you need to let us know what direction you are planning to go in with the car (forced induction or all motor or just a fun daily driver). Bolt on wise, I would say the normal I/H/E is going to be the best for a fun daily driver. A boosted D sries can be a beast, but is going to force you to dig much deeper in your pockets and will require more tuning and maintenance. If you have any more ?s, feel free to PM me. BTW: Welcome to HT and thanks for putting together a well thought out, well punctuated post.

ng

What is your budget like? I'm assuming it's small because of your engine. I think the best thing you can do to keep the MPG you have is to leave your engine stock. If you want performance, like Ricey said, the best tthing you can do is swap.

Green Street

All, cuz I'm a newby, I can only post five times a day, so this response is also for Ricey.

Regarding the budget, lets say the budget is unlimited. It ain't ofcourse, but I'm working up a "build (dream) sheet" and it works best to be open to all options. Also, Ricey, I ain't building a car to race. I just want the optimum performance (mpg and response) out of the VX and, like a racer, I am exploring every tech tip I can.

Please Note: GREEN (wack mpg) + Street (runs and looks better than "normal")

So far the tally is:
Performance Ignition = No Gains due to low hp

?? What about the Cam-Timing Gear and OD Pulley ??

'Preciate the help!!

Ricey McRicerton

the cams and such aernt going to be worth the money you put into them. Just get the basic bolt ons if you are just trying to work with the motor you have. That and a Z6 transmission (or a D16Y8 tranny , which is the same, with the exception of the shift fork). Pulleys are a minimal gain and I would'nt do it. Without a cam gear and tuning a cam really isnt worth anything either. Honestly though, the best bolt on mod you are going to be able to do without swapping the motor or using FI, is the z6 transmission. The transmission you have now is super long and won't allow any kind of decent accelleration.

rodrez.

[QUOTE=Green Street]Not a lot of traffic on this model.

I have a '94 Civic VX with the VTEC-E (D15Z1) engine. I am trying to optimize the car's overall peformance (and looks). Meaning I want to max out the fuel efficiency while also getting the car to run (and look) it's best.

Here comes the questions:
Can this engine run better and possibly add to (but not take away from) the high mpg with...?
o Cam Timing - This is tricky, because of the VTEC-E system, I imagine it would be too difficult for a tuner to find a positive setting between good mileage and improved power. Can't recall ever hearing of a cam gear or adjustments being made to do both
o Overdrive Pulleys - Cheap upgrade, and have been proven to free up some drag. I don't like the fact that the aftermarket versions don't have a harmonic balancer on them, but with this motor, I don't think you're planning to rev it out very high, so I wouldn't be as nervous.
o Ignition upgrade (NGK iradium plugs, performance wires and coil).- I agree with Ricey on this one. Plugs are a good idea, but the ignition boxes and coils that I see in peoples cars are usually causing more trouble than anything else. If you're really set on this upgrade, I remember Jakobs Energy packs being tested and producing increased performance, as well as improved gas mileage. But keep in mind this was a long time ago, when dyno's weren't as common, and test results weren't always accurate.

[Other plans include shaving weight from the battery Excellent way to shave some weight, using a lightweight/race style battery , hood, quarter panels, windows, carbon fiber or fiberglass panels can make a good difference in weight, and the FAL windows make a big difference as well muffler and exhaust. Muffler and exhaust are also places that I am looking to optimize overall performance.]

Gotta get answers to the three questions above first.

Open for any and all advice and suggestions.

Ricey McRicerton

Thanks Rodrez!! Good to see another member who is willing to take a little time out to help out a n00b!! And this way he sees a second thorough opinion.

VTECMaster

hi there, i own a EDM ek3 with the vtec-e too (got 114hp and the D15Z6 engine). if the catalytic converter is combined with your exhaust header than u can replace with a crx si header combined with a civic eg catalytic converter. that brought some power to mine and in combination with bored up throttle body and a fuel pressure regulator i got 135 hp on the dyno. i've seen a civic in austria that got a jrsc kit on the d15z vtec-e engine but it was a lot of work and very expansive. so if u think to gain maximum power it hink a swap to the d16z6 engine is the best u can do

cya

The Alchemist...

I figured I would bring this back from the dead being as I have questions about the same engine…

I recently had a vx swap put in my 92 cx hatch - I would like to know what I can do to make it run really well and be pretty reliable as well. I know the car will never be fast with this swap but I would like to know if there is any basic stuff I can do that will improve the performance overall…

siregcivic

one thing u should do is swap the vx head with the ex/si (d16z6-y8) head 16 valve vtec

and then swap the intake mani and throttle body with the ex/si (d16z6-y8)one also. then you could have something to work with, and also like others said get the ex/si tranny just the change in tranny you should feel the difference in acceleration

The Alchemist...

There is absolutely no info on the D15Z1

eXcelonTypeR

There is someone on here that turbo'd one which was pretty cool. But if this car is your daily driver theres not much that can be done to it. I had one but ended up swaping for a z6 and now i have a B16. The big thing with the z1 is that it's designed to be a lean burning engine, which is why it get great gas milage along with the long tranny. Also the TB and intake manifold are tiny as hell. My friends 250cc TB is like twice as big lol.

Now your best bet would be to get an eBay short ram intake or make one, that helps some. Then take the car to a muffler shop and have that big *** cat (located on the exhaust manifold) removed and a pipe connected to a hi flow cat with 2.25 inch pipe all the way to the muffler put on. Then if you want too, get a z6 tranny, the gears are shorter so you'll acclerate faster but mpg will go down some. Personally I loved my z1 motor, raped the **** out of it....bounced off the rev limiter many times and ran strong till I lost my waterpump .

I wouldn't really touch any of the timing, it might mess up the VTEC-e. If you have another car to drive all the time, I'd try turboing it for fun lol

areem57

The D15Z1 is a VERY unique engine, it burns just as much gas as a 1.0L 3 cylinder and put out more than double its power and still managed to be super reliable. Too bad there is no information on the engine, I was thinking about trying to contact Honda or the Engineers, to try and find out a little more information about the engine.

grumblemarc

iTrader: (4)

Six year old thread. Who are you talking to?