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This site has allowed me to increase my knowledge on my build. I have a 1995 Honda civic DX EG. It has a bare d15b7 in it at the moment. I, currently, have a d16y8 head being serviced that I will be installing. I've purchased a orbital oil pump, arp head studs, a d16z6 Gates timing belt, new water pump (d15) all new gaskets, front and rear main seals, a 225lph Walburo fuel pump, and an AEM Tru timing cam gear. I am aiming for a modest 250-300 hp boosted build. Seeing that I cant post to/for looking to buy yet I'll reach out for insight on my aim here. I'm also excited to install the SI trans I got for DIRT CHEAP! My only few issues are finding the correct rods and pistons to upgrade to. I have looked and researched and asked questions on Honda-tech but I've come up empty handed. Are D16a2 rods comparable? Vitara pistons seem to be my go to. Second issue is I have no idea how to get the SINGLE D16Y8 head stud. I have a kit # and I hope that is enough to have one sent directly from ARP. Thank you all for your time and assistance in my journey. Many of you will say, "get a D16Z6 block." Or "Buy a B series." I'm trying to buy as little possible 馃槄. Any insight is appreciated. THANK YOU D SERIES FAMILY!
 

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89 EF 4wd sedan
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I think you'll find on D-series.org, noone will tell you to go B series.

I swear i was just posting in a thread about someone wanting to put Vitaras in. IMO, they knock far too much compression out of your build. What piston brands have you looked at so far that you chose Vitaras over? Seems like there's plenty of alternatives around.
 

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To be honest I havent. Everything I come across for a 75mm bore are vita's I am foolish for relying on Ebay and Google to assist me. I'm new to the scene and have been doing alot of my own research. I have one person in my town who is ALWAYS busy so I've taken things into my own hands. That, unfortunately, hasn't been reaping any benefits so I'm here now. Your statment reguarding the B series comment is absolutely right. I forgot where I was there while typing out my intro message ��. Any pointers on rods and piston upgrades?
 

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2005 Legacy GT
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You'll find that the D15 block doesn't give you a lot of options, it's not very well supported. I started out wanting to do a beastly D15 build ... but I ended up doing a stroked D16, because it was cheaper.

You might be able to use pistons from other makes other than the suzuki. You'll just have to measure carefully. Or just say fuck it and grab something forged. I can't remember which company(s) offer off the shelf D15 pistons (I want to say JE and CP) but they're out there.

With vitara pistons and a Y8 head you're looking at just shy of 7:1 CR ... your car will suck out of boost. Unless you use VX (Z1) rods, which are a bit longer, then you're looking at 8.5:1 ... but you'll have to mill 0.022" off the top of the pistons to make the sit flush.

If I recall correctly, when discussing this with the guy who built my engine, part of the problem with the B7 rods is the rod bolts are weak. They stretch under that much load, which makes the load forces on the rods wonky enough to bend them. You can get a little piece of mind with some ARP rod bolts, and he said he would have been comfortable running that in the lower 200 whp range if it was his car ... YMMV.
 

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AutoXCivic, I now to your knowledge. I return to you a question. There isnt any other rod that could be used that I wouldn't have to have the pistons shaved? I am under the I derstanding that a D16A2 rod could be used in conjunction with the pistons. I may not have read it correctly but, what your telling me is that a D15Z1 rod is going to be longer thus a shaving will need to take place. A stock D15Z1 rod correct? The ARP bolts are DIRT cheap for connecting rods so that isnt my concern if upgrading to those can assist with bending (or failure) that's 15 bucks well spent. There is a set of rods and positions at custom length for a stack. Which in reality isnt horrible. Thank you kindly for your insight on my situation.
 

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The rods are weak. You bought the wrong timing belt. Your failure to research has cost you money wasted on parts that don't work with what you're trying to accomplish with a block not worth using to begin with.
 

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I don't see where anyone mentioning the H-beam rods that you can get to fit the case and crank of your D-15 build. These are available both online directly as well as Ebay.
Search D-15 b2 H-beam rods and they should pop up. I can't remember exactly all the specs, but I know they'll work and they are very nice.
I bought one of the very first sets as the company was getting them ready to market directly from one of the China or Japan islands. The last time I saw them they were about $345 with high strength bolts. Good luck!
 

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2005 Legacy GT
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AutoXCivic, I now to your knowledge. I return to you a question. There isnt any other rod that could be used that I wouldn't have to have the pistons shaved? I am under the I derstanding that a D16A2 rod could be used in conjunction with the pistons. I may not have read it correctly but, what your telling me is that a D15Z1 rod is going to be longer thus a shaving will need to take place. A stock D15Z1 rod correct? The ARP bolts are DIRT cheap for connecting rods so that isnt my concern if upgrading to those can assist with bending (or failure) that's 15 bucks well spent. There is a set of rods and positions at custom length for a stack. Which in reality isnt horrible. Thank you kindly for your insight on my situation.
The D15z1 pistons have a different wrist pin location than other D15s. Thus the rods are a different length. They are the same length as D16 rods, but have the same size crank end as any other D15.

I think there used to be forged D15 rods (crower iirc) but they are often prohibitively expensive for a vitara build (since most people go that way because of budget constraints).

Let me put it this way. I looked in to building a D15/Z6 mini me, because I wanted to run an under dog motor. Just the rods and pistons (forged) would have cost me about as much the stroked D16 vitara build (including labor) for less pay off.

That being said, my mechanic/tuner said that the really weak part of the B7 is the rod bolts. When you start throwing a lot of power at them they stretch, which causes the rods to get weird side loading, which is what ultimately causes the rods to bend. He said he'd be comfortable running 220 - 230 whp on a B7 bottom end (in his personal car) with just upgrading the rod bolts to ARPs ... I was running about 180whp YMMV.

Going D15 turbo is a lot like going N/A D-series, it's the expensive way to go slow. Unless you have race class restrictions there's really no reason to not wait, save your money, and run one of the tried and true "cookie cutter" vitara builds. Everyone runs them ... because they work.

I went a bit of a different way because of the racing I was doing ... the stroked D16 gave me great low and mid range for AutoCross ... I didn't need a lot of peak power, I needed a lot of space "under the curve".

You'd be surprised how much fun these cars can be with "only" 200 whp. I no longer have my Civic, but I would rate it's fun factor at 130 (N/A) - 180 (boosted) whp above my 335i.
 
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