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'93 Civic D15B7/5spd
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For anyone wanting to do a TL;DR on this topic, YES. It works and it runs great, if you want to swap a Z6 head on your D15Z1 Civic VX, it will run JUST FINE with slightly low compression. It's perfect for boost as the D15Z1 is slightly thicker than the D16Z6 rod.

For people who want pictures, I took a few and a short video to show that she runs well. I had a driving video but my friend was too talky, didn't upload it.

Anyways, on with the pictures, and the swap!


This is the '95 Civic VX in question, it belongs to my friend Jap and it's his DD. He plans on forced induction, but we wanted to do the Z6 swap, convert to a 4-wire O2 and P28 beforehand.


Old head gasket, ARP studs to go in, Felpro intake gasket, Felpro head gasket and a block guard for turbo.


240k+ miles on this head, it was properly maintained and although tarnished it is in VERY good shape. In pretty bad need of a valve adjustment, it'll be going onto the D16Z6 block later, and I'll probably be doing a writeup on it as well.


D16Z6 head, it's nasty. I cleaned it up before I slapped it on there. It had a lot of miles on it but I inspected it and checked it, was in decent shape. About the same as the Z1 head. No port and polish, we're just slapping it on for now. We plan on pulling it again to clean it up for a new MLS gasket when it goes under boost.



Rather than pull the entire timing cover, I just pulled the top cover and slipped the belt off at TDC. It's the easiest way if you're just doing a head swap, make sure to loosen the tensioner and slip the belt off afterwards, don't want to damage the belt. If the belt has a few miles, replace it. In this case the belt was new so I used the old one. I wouldn't reccomend it, but this was on a slight budget, and the belt wasn't very old at all.


I dropped the exhaust down off of the manifold (since it's got the stock manifold + cat) and let it hang, unbolted the manifold from the head and removed the entire thing.
 

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'93 Civic D15B7/5spd
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Discussion Starter #2

After pulling the head off I checked the block surface, it was actually very very clean for the amount of miles on the drivetrain.


This is the D15Z1 head, it's one of the more unique VTEC heads, being VTEC-E. It's roller-rocker assembly is nice, I'll be locking the VTEC arm with a pin and using the head on a high compression N/A build in my own hatchback.



Using a super fine block in a hatch pattern I buffed up the head, checked the Felpro gasket, and then I washed the rest of it off before installing it. But first I had to put in the block guard and ARP studs.




I bumped the block guard in place using the rubber handle of the hammer, use a block of light wood to seat it. Worked out pretty well. (Also, that paper gasket is a BITCH to get off of the intake. I scraped that thing for hours, that's why I always use the Felpro metal fiber ones.)
 

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'93 Civic D15B7/5spd
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Put the studs in and then wiped the oil off of the block, buffed it down as well, and then slapped the head on. My cameraman left after I got the studs in, but I borrowed my friend's Evo 4G and took a quick video when I was all done. Initially got the timing off one tooth but she purred like a kitten after I got it dead on.


I searched around before doing this and no one seemed certain if it would even run because of low compression, on just about every forum where it was asked. I can assure you now that it works just fine, it IS peppier than the stock D15Z1 but expect less bottom end! It comes alive between 3.5k-6k now and definately is an upgrade if you have a D16Z6 head laying around.

The car in this is, again, my friend's EG VX. It's planned for boost but we're taking it slow to do it right, it will be a Garrett TB03 or TB0344, internal WG, and will be daily driven at 8 or 12 PSI (it depends on the numbers we pull). I'm shooting for 250+ with that setup and DSM 440cc on 93 octane, I think we can at least get close if not more than that on a good tune.

Anyways, long story short, we tried it and I wanted to let everyone know how it is. Definately better than the stock VX. Paired with 4-wire O2 and a P28, with the D16Z6 intake, I think you could pull power numbers close to a stock D16Z6.

It is DEFINITELY a forced induction platform though, don't expect any big N/A numbers from the dishes and stock bottom end.

If you have any questions, just ask. As far as issue, we didn't run into any at all. The swap was flawless, everything bolts right up. ;)
 

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how was the 5 wire to 4 wire conversion done? should i just repin straight to the ecu? i have a p07 ecu in my turbo vx right now, and am installing my chipped p28 and 450cc inj but cant find a good source of anyone who did the swap? Thanks!
 

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^^ not all VX's were 5 wire. california VX's were 4 wire. 49 state was 5 wire. the lean burn mode emitted too many NOx( I think) emissions, a by product of the extra heat from running lean
 

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yeah im aware of that, but mine is a 5 wire o2. would it be best to run a wideband o2 controller on the p28 or just convert? but ive seen too many different threads of how its been done and seems to be easiest to just repin straight to the p28.
 

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take a look at your ecu plugs. do most, if not all the other sensors and shit match up to regular obd1 4 wire setups? if so, then a repin and maybe a new 4 wire plug would work just gravy!


Have you done a search on 5 wire conversions? Im sure someone has done a similar thing where they were resourceful and reused as much of the factory wiring as possible
 

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97 EJ6 boosted D16Z6
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user Wischmaster on this site has had this combination with a greddy 15g for a few years
 
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