Civic EG

I have a 95 CX which come with a D15b8? 70 HP only ?

I am swapping in a D16Z6 head, intake manifold/throttle body an the head also adds VTEC. With this simple ugrade how much gains in HP should I expect? I always thougnt I had a D15B7 which has 30 or so more HP then the D15B8.

I also have an aftermarket header/downpipe which I will be installing as well.

I will be adding turbo eventually. My WHP goal is 180-200 which I'm pretty sure i can get away with on stock internals. . .

Any suggestions would be greatly appreciated. . .

I really hate bench racing stuff like this because every motor will not act the same to the same mods.

I'd say you'll be in the 110hp range. You'd be at almost 10:1 compression(according to the zeal calculator). 6-8psi off a small snail would get you close to your goals on a good tune

I think you would be close to 127hp (same as d16z6 at the crank)
Your motor will be a 1.5L version of the D16z6 with slightly higher compression to make up for the difference in displacement.
That's if you upgrade to the z6 TB, intake manifold/injectors & P28 ecu as well.

Someone can correct this if I'm wrong but from what I've heard the d15b8 pistons only have 8 piston reliefs unlike 16v motors that have 16 reliefs which would make it so you couldn't do a mini-me swap.

but I'm not 100% since I've never owned a B8

the 12 valve (b7 or b8, dont recall) has valve reliefs for the 16 valve head so you can do a mini me on it.

I have the D16Z6 head, IM, TB and injectors. I will be putting in the P28 as well so I can run the VTEC. O plan on going boost so I would want a lower compression correct? So I would go with the Z6 head gasket?

If I installed all these components and everything goes peachy then I should be close to the 127 HP mark? Thats a big leap from my stock 70hp.

I do realize that you can't be 100% positive on how much gain you will have uness you hit the dynbo. I am just curious.

Stock they were 90 or 95 hp lol

chrono404 wrote:the 12 valve (b7 or b8, dont recall) has valve reliefs for the 16 valve head so you can do a mini me on it.

The B8 n the cx was an 8 valve head

try a b series motor

Josiah wrote:try a b series motor

try posting something useful

i did. ill donate

be a post whore in the Junk Yard from now on or you'll be donating your post count

teal_dx wrote:be a post whore in the Junk Yard from now on or you'll be donating your post count

Can I have them? lol

Idk if this is true but i heard that the b8 has flat top pistons that will result in a higher compession? i had a b8 like 2 months ago....hated it

CaliEJ2 wrote:

teal_dx wrote:be a post whore in the Junk Yard from now on or you'll be donating your post count

Can I have them? lol

Idk if this is true but i heard that the b8 has flat top pistons that will result in a higher compession? i had a b8 like 2 months ago....hated it

I don't think that is true. They looked like D15b7 pistons I think, but I only took one D15b8 apart and it was a while ago. I can't say 100% for sure.

nekim wrote:O plan on going boost so I would want a lower compression correct? So I would go with the Z6 head gasket?

Yes and No,
When you lower compression you loose power. If you go with lower compression pistons you will need to crank up the boost, meaning longer spool times to get to where you would be if you use pistons at the same Compression.

However if you go with lower compression it will be easier to tune. However if you are going to have it professionally tuned this isn't that big of an Issue.

My Stock z6 + I/h/e smoked a "Built" z6, it had vitaras and forged rods. He was boosted however had a massive boost leak, Therefore was easily smoked. If he had OEM compression that wouldn't have happened.

I would recommend forged Rods, maybe oem compression forged pistons, but i wouldn't put more than that into a D15 block.