WTB: 92-95 civic vx head d15z1 VTEC-E
09-06-2005, 01:20 PM
#3
* B A N N E D *
Join Date: Jun 2004
Location: Encino, CA, USA
Posts: 32
Likes: 0
Received 0 Likes
on
0 Posts
09-07-2005, 08:42 AM
#4
Honda-Tech Member
Join Date: Jun 2005
Location: Salt lake City, UT
Posts: 965
Likes: 0
Received 0 Likes
on
0 Posts
Re: WTB: 92-95 civic vx head d15z1 VTEC-E (bense)
I have one too. 130k on it. I bought it for a mini-me but I might end up just buying a whole engine. I'll sell it to you for cost+shipping. BTW, this is Matt from gassavers.
09-07-2005, 12:54 PM
#5
Go Tigers!
Thread Starter
Re: WTB: 92-95 civic vx head d15z1 VTEC-E (SiMateoAko)
hey matt, i heard that there was an issue when doing just the head swap. due to the fac tthat the z1 uses different pistons than the d15b8, do you know anything about this?
09-07-2005, 02:31 PM
#6
Honda-Tech Member
Join Date: Jun 2005
Location: Salt lake City, UT
Posts: 965
Likes: 0
Received 0 Likes
on
0 Posts
Re: WTB: 92-95 civic vx head d15z1 VTEC-E (bense)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bense »</TD></TR><TR><TD CLASS="quote">hey matt, i heard that there was an issue when doing just the head swap. due to the fac tthat the z1 uses different pistons than the d15b8, do you know anything about this?</TD></TR></TABLE>
Yeah. Here's the deal. The combustion chamber volume of the z1 head is much smaller (like 10 cc smaller) than your b8 head. This is compensated for on the z1 block with REALLY domed pistons. The rods are also a little bit shorter (3mm) to compensate for the pistons.
If you just throw the z1 head on the b8 block, as I planned on doing, you'll end up getting a compression ratio of about 12.3:1, which is ridiculously high, especially if you're building for fuel economy.
The solution is to buy a z1 head and also buy a set of z1 pistons and rods (code is p07). these will fit with your b8 crankshaft, and since the bore and stroke of the b8 is the same as teh z1, you'll be fine there too. You can get the new rods/pistons for about $150 on hondapartsdeals (maybe less, I'm guessing here). you'll also need new rings while you're at it (like $5 I think). Or you can buy them from a guy I know who is selling them for much less. I believe they have like 50k miles on them... maybe 60k, not sure.
Anyway, if you put the z1 (p07) pistons and rods into your block you'll get about the same compression ratio, and then you'll won't need to run 93 octane to avoid pinging.
remember, there are a few other reasons the z1 gets such great mileage. part of it is the vtec-e, but to properly use that you also need the p07 ECU and the 5 wire o2 sensor. you'll probably also need the exhaust manifold as the o2 sensor is in a differnet location. Another thing to consider is the VX transmission. When I do my build I'm going to put in the HF transmission so that I don't have to convert to hydro. I'm guessing the long geared transmission alone should give you a 5-10 mpg boost.
So to answer your question, that's why you can't just put a z1 head on a b8 block.
Yeah. Here's the deal. The combustion chamber volume of the z1 head is much smaller (like 10 cc smaller) than your b8 head. This is compensated for on the z1 block with REALLY domed pistons. The rods are also a little bit shorter (3mm) to compensate for the pistons.
If you just throw the z1 head on the b8 block, as I planned on doing, you'll end up getting a compression ratio of about 12.3:1, which is ridiculously high, especially if you're building for fuel economy.
The solution is to buy a z1 head and also buy a set of z1 pistons and rods (code is p07). these will fit with your b8 crankshaft, and since the bore and stroke of the b8 is the same as teh z1, you'll be fine there too. You can get the new rods/pistons for about $150 on hondapartsdeals (maybe less, I'm guessing here). you'll also need new rings while you're at it (like $5 I think). Or you can buy them from a guy I know who is selling them for much less. I believe they have like 50k miles on them... maybe 60k, not sure.
Anyway, if you put the z1 (p07) pistons and rods into your block you'll get about the same compression ratio, and then you'll won't need to run 93 octane to avoid pinging.
remember, there are a few other reasons the z1 gets such great mileage. part of it is the vtec-e, but to properly use that you also need the p07 ECU and the 5 wire o2 sensor. you'll probably also need the exhaust manifold as the o2 sensor is in a differnet location. Another thing to consider is the VX transmission. When I do my build I'm going to put in the HF transmission so that I don't have to convert to hydro. I'm guessing the long geared transmission alone should give you a 5-10 mpg boost.
So to answer your question, that's why you can't just put a z1 head on a b8 block.
Thread
Thread Starter
Forum
Replies
Last Post
