what motor to put in hf crx

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cREX

New Member
Soo the crank in my 91 hf crx is fucked and i need a motor soon. i was thinking of building the motor but dont know if i want to or swap it with etheir a jdm d15b vtec or jdm zc sohc or dohc. im not trying to spend a whole lot right now thats why im going with one of these motors. my question which motor is the best for what i want right now. i do want the car to be quick but i also know their is only so much u can do on a budget of less than 800 or 900. my question is , which is the best motor or am i better of building the stock d15b6 motor?
 
Well the d15b vtec is obd-1 so you're gonna have to do a wiring conversion for that. If you buy the swap you will also either have to use your shitty hx trans, buy an si cable trans, or get a hydraulic-cable conversion for the swap trans.

The zc swaps will bolt right up which will be nice. If it were my pick I'd take the dohc just because I hear it responds better to add ons compared to the sohc motors.
 
ive heard that you have hood issues with the dohc zc.. is this true or just some shit? i kinda would like to get a jdm d15b vtec but will i also have to get a ecu from the same year as the ecu and same goes for the zc , will i need to get a different ecu for it. thanks for your reply
 
You need to run the ecu that is designed to run that particular engine. If you run something else, then the motor will either see too much or too little fuel and timing. You will not be getting the most out of the engine that way. The dohc zc should fit just fine. I know a b16 fits no problem. It's when you get into the taller deck b18's that there can be problems.
 
Well there is no vtec dohc zc, and the sohc vtec zc is basically a d16z6 so it might be obd-1. I'm pretty sure that the sohc has more aftermarket support, and because it is simmilar to a z6, parts are easier to find. Because of that, I'd go for one of thoes.
 
I have a D15b with a y8 head and Si tranny Ill sell for $300.

Hey SIdude, Honda meet in Columbus coming up soon, I forget when exactly but yeah.
 
found a jdm d15b vtec motor , would i need to get the p08 ecu with it ? and also if i got the ecu would that control the vtec? thanks for your guys help
 
You need the po8 to run the d15b correctly. The ecu will run vtec correctly, but will be needed to be wired up to run. You will also have to convert to obd-1.
 
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I was using a P28 on my D15B VTEC; worked fine.

If you're going for a more budget route; slap on a PM3 head from any of the 16v 88-91 D-series, Si cam, Y8 header, ported IM, and you'd have a decent setup right there. More power is also possible with the addition of P29 pistons, reground cam, header, ITB's or carbs, etc.

The D16Z6 would probably be easier/cheaper to procure than a JDM D15B.
 
That is why I mentioned the d16z6 its easy to get and cheap. With lots of places to find, not to mention its obd-1 which makes it even easier to tune. You want a cheap option to make decent power, buy a pep boys intake and some extra bends and couplers make your own cold air intake, buy a welder and a header and high flow cat and weld yourself an exhaust, buy a b, f, or h-series throttle body, port match your header, intake manifold, and throttle body and port your head. All of the porting the exhaust and the intake will add around 20-30 horses and will cost you almost nothing.There are a ton of port n pollishing write ups out there.
 
Just port work, homemade i/h/e, on a D-series will not add 20-30hp. In some cases, you may even lose power due to loss of velocity in some areas.
 
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honestly whats wrong with the jdm d15b cause ussually when someone mentions the d15b vtec someone else tells them to get a different motor. i kinda am planing on gettin the d15b just cause i dont feel like building up a motor also i dont have the time.. but i figured down the road id put ITB's , cam , and a good tune along with full exhaust. not looking to get crazy
 
Because you'd most likely have to order a D15B or look hard to find one.

Nothing's really wrong with it, it's just that it's equivalent to the D16Z6. The Z6 is more readily available and can usually be had for cheaper. You say you're on a budget, so getting a cheaper Z6 would allow you to spend more money on mods.

BTW, I'm running a D15B VTEC. I got lucky on that one and found someone who didn't know much about engines selling it for $200 incl ECU, intake, and header(he broke one of the valve cover studs and thought the head was ruined...he never ran it either).

Honestly, that wasn't my first choice. I was looking for a D16Z6 or A6. I also got lucky on the transmission too; found a DOHC ZC transmission for $70 that was pretty much unused by the buyer (had around 30k miles, motor was around 35k). Spent like $40 on a CRX Si countershaft and EG differential, and now have something "better" than a stock Si transmission. :D
 
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