Civic Vx engine question. stock exhaust manifold vs. stock exhaust manifold

[vtecn8ive]

I'm curious if the d15z1 (civic vx) engine will run properly if you use a regular obdo exhaust manifold and down pipe.

The d15z1 has the o2 (5-wire) sensor on top of the manifold (think of hf manifold) and its right before the catalytic converter.

The d16a6 (one of the stock obdo exhaust manifold) is a header type 4-1 style and the catalytic converter is after the down pipe.


On my Civic rt4wd I need to clear the transfer case and so I either need to modify the d15z1 down pipe or I can run the d16a6 without modifying it and just stick the 5-wire sensor in there.


Any suggestions?

Thanks,
Shane

[SVOboy]

I remember your posts on honda-tech from years ago with nostalgia, good sir.

Anyway, I wouldnt do it, the readings will likely get a little wonky and it the heat issues will likely also affect lean burn.

[vtecn8ive]

I remember you as well. Your Lx with the d15z1 swap always made me want to go this route (well a 4dr at least)

Thats what I wasn't sure of. I kind of assumed it would affect it... but i was hoping I could get away with the d16a6 stock header

[SVOboy]

Haha, you are remembering matt, not me. I think his handle was mltimion or something like that at the time. He and I started GS out of that, but I since moved on to cofound this site when matt lost interest. At the time I had only my car in stock for, but I have since had the chance to drop in a z1.

I am sure you can get away with it, but it is a fine-tuned system and it even if it doesnt go completely borked, you will probably reduce the efficiency of it incrementally. You could try it while monitoring the afrs in various situations and try to find a comparison for things like start up times, afrs in various running conditions, etc if you felt ambitious and wanted to do a real ecomodder's test on the subject.