sadler300d16

Hey guys! I apologize if format is off a bit as to this is my second post ever, but let's get down to business. I have a D15b7 in a 95 civic dx hatch and while waiting for the rest of the components on my turbo d16z6 motor build I decided to see if I could squeeze more horsepower out of the B7 using oem parts I had laying around. I have access to a Superflow chassis dyno and wanted to see baseline numbers.

In 100% stock form, the D15b7 made 82.2hp and 82.8tq.

First upgrade was a D16z6 intake manifold. The intake runner diameter is larger and flows a little bit more air, throttle bodies are same so that remained stock. Pretty much direct fit no modification required.

Second upgrade was a cheap set of headers. If you don't want to spend the money, get a oem d16z6 cast exhaust manifold. The difference between D15b7 and D16z6 exhaust manifold are that the z6 has a 4-2-1 design compared to a 4-1 small diameter on the b7. These exhaust manifolds are everywhere and can be had for little to no money.

Third upgrade was a D16a6 camshaft. The cam will drop right in using stock D15b7 valvetrain. YOU WILL NEED a D16y8 cam gear due to the D16a6 camshaft being 4.5° off timing. The D16y8 cam gear fixes that problem and stock timing belt and components go back together nicely. Other option is buy an adjustable cam gear. Just to be clear, D15b7 head, D16a6 camshaft, D16y8 cam gear.

The final power numbers were 95.3hp and 81.2tq. That's a 13+whp increase just from oem Boltons! You can definetly feel a difference especially on the top end.

Let me know what you guys think!

White_EG1

Wow a whole 13hp that's pretty dope. The torque curve is underrated on these motors as well @4500 99tq (out the factory) Is pretty cool considering the motor barely had 100bhp. And how the torque falls right under the power.
First thing I did on mines. You definitely can feel the difference and I could keep up with z6's and I've beat a 1.6l Miata with bolt ons.

One thing you forgot to mention is how vital having the z6 transmission is. It's night and day. The dx transmission will do everything in its power to make sure you don't shift into powerband... Its crazy but the z6 clears all that up.

I supposed you could get aftermarket valve springs and a more aggressive cam to rev it to 7200 to net even more power.

sadler300d16

Of corse the Ex/SI trans is definetly the way to go, that mated with a lightweight flywheel and youll get better acceleration. This was just what I've done so far, im planning on adding a b18 throttle bodie on it as well. Just poking around while I have a dyno at my disposal so I can get actual data

Txdragon

I catch a lot of grief over modding my B7 but yeah, it is underrated. I've gotten all essential bolt-ons, skunk2 intake manifold and 70mm throttle body, short throw shifter, header, 2.75" catless exhaust, short ram intake, 8lb flywheel, stage 3 clutch (those are recent). Neptune engine management to tune it all up. I've finally gotten my tune to where I want it. Playing around a tad with my timing still, but nearly there. I'm almost optimal at WOT running at 13:1 a/f at 28.5 deg timing (I'm trying for 29). I dont have access to a dyno but a conservative guess would say I'm around 110-115whp. Anywho..
My theory is the B7 CAN be a great platform, IF you don't expect too much from it. You're not going to get super high numbers N/A without spending massive cash, and you can't go stupid boost crazy due to lack of aftermarket support. A mild, modest turbo setup netting 200hp would be sufficient, making it a fun drive. Think as well about the car's this engine is in; they are all pretty light making the power to weight ratio rather competitive.

sadler300d16

You said it yourself as long as you don't expect much out of it, it's a pretty entertaining little engine to play with.