I recently completed a motorswap on my 94 LS to a JDM B18B from a 98 LS (mainly due to my original motor had over 160,xxx miles on it and I got a good deal on the JDM motor with 45,xxx km on it for only $300.)

Prior to motor install, I changed all belts, new spark plugs, new clutch and
of course all fluids. I didn't change the O2 sensor. I had transferred the intake manifold, valve cover, and tranny from my original B18B. Everything bolted up no problem, but there was however a difference between the two motors which was the PCV system. From the 94 B18B motor, the PCV valve went through the intake manifold to a canister which was connected to the block, which the 98 B18B had the PCV valve connected directly to the valve cover. So, to complete my swap, a friend of mine suggested just doing without the PCV valve (since the PCV system canister doesn't connect to the 98 block).

Note: My current mods to the car is only a lightspeed 4-2-1 ceramic coated header and 5Zigen exhaust. I took off my aluminum intake kit and reinstalled the stock air cleaner.

My question is, does this affect my overall engine performance? My symptoms are 1) Sluggish or no low end torque/acceleration, 2) exhaust note got significantly louder, and 3) GAS MILEAGE IS REALLY BAD (I'm currently at 40 miles at half a tank of gas on 87 octane). If the PCV valve is the culprit,
should I revert back to the 98 B18B valve cover and connect the PCV valve directly to the valve cover? Should I also change the O2 Sensor and have the car retuned?

Any help you B series motor gurus can provide would be greatly appreciated. Thanks a million!!!

 

i would take the motor in to get service... ur o2 sensors could be the reason ur geting bad milage... jdm motors tend to run a lillte richer as well...

 

PCV stands for positive crankcase valve or something right. I dont know a lot on the topic, but I kinda have an idea what it does. I think it monitors or maintains the correct air or something for your motor. Like it works inconjunction with your o2 sensor or something. If i read your post correctly, you didnt hook it up? If im correct, you should probably hook it up. Having the wrong amount of air exploding in your engine would probably affect compression. Like the perfect Air/Fuel ratio is something like 14.7:1 or 12.4:1, (12parts air, 1 part fuel) I forget, but that ratio gives the best bang for the buck. If you had like 10:1, it would probably feel sluggish.

 

Positive Crankcase Ventilation.

I think you should use the newer valve cover, with it's PCV valve, to hook it up like a newer B18B is supposed to. Because your new block would have to be drilled to accept the vent box from your old engine, so you won't want to do that.

I'm guessing that this won't be enough to fix your problems with bad running. But it's probably enough to mess you up trying to figure out any other problems.

 

ok question...its retarded...i bought gsr that was strippped...and i just got it running....the exhaust from the cat back is gone...it has a check engine light....where is the o2 sensor in a teg?? lol dumb *** question...

 

'96 is OBD-2 so the primary sensor is in the exhaust just ahead of the cat. The secondary is in the cat, actually after the catalyst itself.

 

so what about obd 1...i have a 95 gsr\

 

its on the bottom of your header just before the cat. get underneath your car and you'll see it

 

Another question for you guys. Do you think my exhaust piping diameter of 2.5" from the cat back could be too less restrictive against the JDM B18B and causing part of my problems?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 96teggyls &raquo;</TD></TR><TR><TD CLASS="quote">so what about obd 1...i have a 95 gsr\
</TD></TR></TABLE>OHhhhhh... I figured it would have been a '96 LS...

On a '95 GSR your only O2 sensor is mounted in the inlet end of the cat. It's upstream of the catalyst itself, but it's in the cat housing. Not in the A-pipe.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ishdatjaypee &raquo;</TD></TR><TR><TD CLASS="quote">Another question for you guys. Do you think my exhaust piping diameter of 2.5" from the cat back could be too less restrictive against the JDM B18B and causing part of my problems?</TD></TR></TABLE>

i think your fine as far as that goes

 

Another question for you guys. Do you think my exhaust piping diameter of 2.5" from the cat back could be too less restrictive against the JDM B18B and causing part of my problems?