David_EJ1

I've finally become stable enough to work on my first car I ever got which is a 1993 honda civic coupe ex D16z6 with an automatic transmission. So I wanted to mod it as a project car and ultimately make it my daily driver with some nice power. I want to stay with a D16z6 engine and mod that but have concerns about it being an automatic tranny. I guess what I'm asking is will it be pointless to mod my car an automatic tranny or will I need to swap to a manual? And is swapping a manual tranny difficult?

NotARaCist

iTrader: (1)

Yes, modding an automatic is pointless. For that matter, modding a D series outside of adding FI is pointless - you won't see any real power gains without spending literally a shitload of money.

There are two problems with trying to build up a D series car with an autotragic. First, and the simplest to explain, is the power handling. A D series automatic transmission simply can't do it. As soon as you start going past stock power levels, the clutch packs **** on you, and there goes your transmission. The second reason is tuning. If you want to actually build any car, tuning is necessary. With Hondas, the TCU is integrated into the ECU, so your ECU has to match the engine and transmission. To tune the car, you have to step down to an OBD1 ECU, or a standalone system. Standalones don't have the provisions to control an automatic transmission, and literally no tuner in their right mind would fiddle with the TCU, because A) there isn't any software out there to do it, and B) see reason 1.

In short, if you want to just fiddle around, turn some wrenches, and toss some bolt-ons on there, go for it. It won't matter. You'll gain zero noticeable power from it, because that's how D series engines are. If you actually want to make proper power, you need to swap to a standard transmission, and then you either need to swap to a better power plant, or you need to force feed that motor.

v4lu3s

Its not too hard to increase output of a d series until it approaches the power levels of a b16a that is stock and will cost less if done with some planning. More than a few people have made 120+ hp on the d15b7 with a milled head, intake manifold, d16a6 cam, bolt ons and tuning and it cost very little compared to a swap.

I have swapped d series out fit h and b series engines, but my current setup is a high compression d16a6. I spent $400 in parts, $300 sty machine shop and daily drive a 12:1 crx. I did eventually convert to obd 1 and got a Hondata s300. At this point I'm still under the cost of a swap to a b18b or b16a though, and once I get a cam I will be even....but have a low mile fresh engine making 140ish horsepower and getting 32+ mpg.

Check out d-deries . Org and onecamonly they have a lot more knowledge than this site does. The auto transmission will hold you back, just work on the car and build your skills and tools until you can go five speed.

NotARaCist

iTrader: (1)

$300 for a decent cam (looking a Crower). Another $150 for springs and retainers, if you go with Crower's cheaper option. $50 for a cheap header, $300 for a good one. $500 for tuning. You're now in for a grand with a cheap header, $1250 with a good one, and making what, 170 to the crank on a D series with an obnoxious idle? For that money, you could do a stock LS swap with a much better idle, and a hair less power, or spend a little more and get a GSR or ITR swap, make more power, and have the ability to make even more power down the road through building or forced induction.

It's not entirely impossible to build a naturally aspirated D series, it's just silly. You can make more power per dollar with literally any different engine.

86azms3

Listen to notaracist. He is wise.

The D series is good for economy. Without forced induction, just forget it. "Some ************* are always trying to ice skate uphill" Blade

Best option is to save up for a better car, or if you like your civic that much, a better engine with better aftermarket. Say like a B series.

angrysmileyface

Why on earth would you want to keep the D's tranny? As mentioned before it is designed for economy. Honda wanted your auto econobox to be the best grocery getter on the market. And even then they still didnt perfect it. This is why people have to do the 3x3 drain and refills to often get the crapped up transmission to run right.