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I have a 1991 civic dx with the d15b2 motor and I'm looking to do some semi-budget upgrades. Its my daily driver but wantt a little more get up and go. I did an obd0 mpfi swap over the summer. Now im thinking about rebuilding the motor. I was gonna upgrade the valve train with a d16a6 camshaft and a supertech valve train kit. I was also thinking about putting in some better piston rods and possibly oversized pistons maybe but I'm not really sure if thats worth the investment or not? If i were to do all that would i need to upgrade to obd1 or 2. And which ecu would i use?
 

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Are you running the PM6 ecu for a d16a6? Could just grab a d16a6 and freshen it up and toss it in. There is your extra oomph without much hassle. Toss in some PG6 pistons for a nice jump in compression and play around with ignition timing to smooth it out, and it will also return a little extra fuel economy during normal driving.
 
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Yes i am running a pm6 ecu. I've thought about getting a d16a6 but they're kind of hard to come by in my neck of the woods
 

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We run a D15B2 in our little crap can hatch rally car. The last time we were on the dyno, we got 113whp and 91lb/ft torque.
Here's the build. Bored 75.5mm, A6 cam, mpfi swap, ZC intake, ebay 4-2-1 header with 2.25" exhaust, head shaved .030", 3-layer mls head gasket, OEM rods, pistons, crank, valve train. We use a MegaSquirt 2 and tuned it on 92 pump gas. This is about as low budget as you can get and it ended up being a little ripper. It's been raced for 7 seasons and hasn't had the head off. You're mostly where we are, so you should see similar gains.
 

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Yes i am running a pm6 ecu. I've thought about getting a d16a6 but they're kind of hard to come by in my neck of the woods
Can you find d16z6's out of the 92-95 ex/si cars? use that block with a d16y7 head from a 96-00 dx/lx/cx civic, and you have an "upgraded" d16a6 with slightly higher starting compression and MUCH better stock head flow/port design.

Plus, you can shave the head down quite a bit for some extra compression, leave the block stock, but perhaps refreshed a little, and have quite a reliable daily
 

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Can you find d16z6's out of the 92-95 ex/si cars? use that block with a d16y7 head from a 96-00 dx/lx/cx civic, and you have an "upgraded" d16a6 with slightly higher starting compression and MUCH better stock head flow/port design.

Plus, you can shave the head down quite a bit for some extra compression, leave the block stock, but perhaps refreshed a little, and have quite a reliable daily
I like your idea. Both of those motors are fairly easy to get a hold of. My only concern is If i were to use the z6 block i would have to do hydro clutch conversion right?

We run a D15B2 in our little crap can hatch rally car. The last time we were on the dyno, we got 113whp and 91lb/ft torque.
Here's the build. Bored 75.5mm, A6 cam, mpfi swap, ZC intake, ebay 4-2-1 header with 2.25" exhaust, head shaved .030", 3-layer mls head gasket, OEM rods, pistons, crank, valve train. We use a MegaSquirt 2 and tuned it on 92 pump gas. This is about as low budget as you can get and it ended up being a little ripper. It's been raced for 7 seasons and hasn't had the head off. You're mostly where we are, so you should see similar gains.
So the block and head is mostly stock except the a6 cam and oversized pistons?

What about just swapping the b2 head for an a6 head? I can get a rebuilt one for about $400-500
 

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We run a D15B2 in our little crap can hatch rally car. The last time we were on the dyno, we got 113whp and 91lb/ft torque.
Here's the build. Bored 75.5mm, A6 cam, mpfi swap, ZC intake, ebay 4-2-1 header with 2.25" exhaust, head shaved .030", 3-layer mls head gasket, OEM rods, pistons, crank, valve train. We use a MegaSquirt 2 and tuned it on 92 pump gas. This is about as low budget as you can get and it ended up being a little ripper. It's been raced for 7 seasons and hasn't had the head off. You're mostly where we are, so you should see similar gains.
This is amazing... 113whp? Thats got to be so much fun!

I'm picturing this now haha:

 

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I like your idea. Both of those motors are fairly easy to get a hold of. My only concern is If i were to use the z6 block i would have to do hydro clutch conversion right?
why? the other D motors bolt up to your current trans/clutch/flywheel
 

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Could also make it easier by simply dropping in a complete d16y7, and re-use all the manifolds and electronics. I do believe your current distributor will bolt up to the d16y7 cylinder head even. Well worth a check (hint d16y7/y8 is OBD2, you have OBD0 for the electronics catergory)
 

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So the block and head is mostly stock except the a6 cam and oversized pistons?
Yep. Just a touch of port matching and cleanup (molding lines and such). I have some knock-off h-beam rods for it when ever we end up opening it up again. Probably do those and better valve springs. It was still making power at 7k, but we got scared of going further on old oem springs. Or, we'll just keep sending it and rebuild when it blows. :)
 

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This is amazing... 113whp? Thats got to be so much fun!

I'm picturing this now haha:

That's close!!! :eek::cool: At the last Oregon Trail rally, we hit a jump at about 85mph and were airborne for about 45 feet.

It's stupid fun. We have it pretty much dialed in with suspension, brakes, and weight balance. You can blast into a corner, slam on the brakes, and and skandi flick your way around it. Get it pointed somewhat in the right direction and pin it to the next corner!
 

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Discussion Starter #13
Yep. Just a touch of port matching and cleanup (molding lines and such). I have some knock-off h-beam rods for it when ever we end up opening it up again. Probably do those and better valve springs. It was still making power at 7k, but we got scared of going further on old oem springs. Or, we'll just keep sending it and rebuild when it blows. :)
Thanks. I'll be following your advice. Seems like the easiest and most cost effective way to get the effect i was going for
 

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We run a D15B2 in our little crap can hatch rally car. The last time we were on the dyno, we got 113whp and 91lb/ft torque.
Here's the build. Bored 75.5mm, A6 cam, mpfi swap, ZC intake, ebay 4-2-1 header with 2.25" exhaust, head shaved .030", 3-layer mls head gasket, OEM rods, pistons, crank, valve train. We use a MegaSquirt 2 and tuned it on 92 pump gas. This is about as low budget as you can get and it ended up being a little ripper. It's been raced for 7 seasons and hasn't had the head off. You're mostly where we are, so you should see similar gains.
That's good power.
 

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Henry's setup is basically my D15Beast7 with correct cam timing. I did 118 WHP with the cam retard 1/2 tooth due to block height issues. With a fresh rebuild like his it might have been 122-125 whp (dynos differ) but the D15 only loses 2-4 whp to the D16....but the D16 has better TQ.

Imagine if you had a D15Beast7 with a close ratio trans and swapped in a D16Z6 with VTEC, IHE and trans/slicks stayed the same and you only went .06 quicker in the 1/4 mile, an it was all at the first 60 ft. on the launch. That was 1999-2000.
 

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Henry's setup is basically my D15Beast7 with correct cam timing. I did 118 WHP with the cam retard 1/2 tooth due to block height issues. With a fresh rebuild like his it might have been 122-125 whp (dynos differ) but the D15 only loses 2-4 whp to the D16....but the D16 has better TQ.

Imagine if you had a D15Beast7 with a close ratio trans and swapped in a D16Z6 with VTEC, IHE and trans/slicks stayed the same and you only went .06 quicker in the 1/4 mile, an it was all at the first 60 ft. on the launch. That was 1999-2000.
We built the B2 instead of going to a A6 or a B series of some kind for class rules. The rules have changed so we can do just about any motor swap we want now. Just to add to the mix, the trans is loaded with an MFactory close ratio gear set and a Quaife LSD (got a great deal on the lsd). The gear set rules on stage. Second to up grading to proflex suspension, the gear set is the biggest improvement we've done.
 

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With a D15, gearing is everything.
 
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