Hey everyone.

Last year in July (2016) I was finally able to get my NA d16z6 build dyno tuned and I was very happy with the results. It made 156whp and 115wtrq.

The car is a 1993 Honda Civic del Sol Si. All the details of the build can be found here:
https://honda-tech.com/forums/all-mo...-dyno-3282238/

In the off season I decided that I wanted to try to improve on this project by improving the airflow in, fuel delivery and exhaust flow. Last year I was using a generic air filter, 56mm d16z6 throttle body, 60mm ported y8 intake manifold, Megan Racing 4-2-1 header with 2" collector, Magnaflow high-flow catalytic converter and Tanabe Medalion 2.25" exhaust. I'll put the details of the current parts list below.

I was planning on using RDX 410cc injectors but my mechanic was unable to find the hats. Turns out that it was a blessing in disguise. The tuner told me that I wouldn't have been able to drive the car had they been installed due to the significant increase in fuel without a proper tune. I consequently found the hats in the Takata harness box...

I'll be getting them installed and tuning the car again. Stay tuned for a pre and post RDX injector thread with dyno graphs.

Parts List:

Exhaust:
- 1320 4-1 RMF header (2.5" collector) - (previously Megan Racing 4-2-1 header)
- Vibrant Metal Core catalytic converter (2.5") - (previously Magnaflow high-flow catalytic converter 2.25")
- Vibrant Ultra Quiet resonator 2.5" - (previously what came with the Tanabe Medalion 2.25" exhaust)
- Vibrant Ultra Quiet resonator 2.5" as muffler - (previously what came with the Tanabe Medalion 2.25" exhaust)
- Trubendz pre-fabricated 2.5" stainless steel mandrel bent exhaust - (previously what came with the Tanabe Medalion 2.25" exhaust)

d16z6 block:
- resurfaced 0.004", rebuilt: Top Line gasket kit
- bored to 75.5mm
- P29 pistons (Nippon Racing) - 75.5mm
- NPR piston rings
- ACL race bearings
- ARP rod bolts
- crank journals resurfaced
- Innovative Mounts AT-MT passenger side mount 60A (red) Polyurethane
- Innovative Mounts rear side mount 75A (black) Polyurethane
- Innovative Mounts driver's side mount 75A (black) Polyurethane
- 11.4lbs Competition Clutch flywheel
- miscellaneous parts (i.e. water pump, belts, etc) all Honda OEM

d16z6 head:
- ported and polished
- resurfaced 0.004" (IIRC)
- Rocket Motorsports stage 4 camshaft (re-grind of stock d16z6)
- Rocket Motorsports valve springs
- Rocket Motorsports titanium spring retainers
- AEM Tru-Time camshaft gear
- ARP head studs
- Cometic 75.5mm head gasket
- Denso spark plugs gapped and supplied by Rocket Motorsports
- Skunk2 intake manifold - (previously d16y8 intake manifold - ported to 60mm and polished inlet and runner outlets ported to match head intake ports)
- OBX plastic intake manifold gasket cut to match head intake ports
- 60mm b18b throttle body with KMS FITV block-off plate - (previously 56mm d16z6 throttle body
- generic short-ram intake
- Skunk2 air filter with velocity stack - (previously generic cotton air filter)

Miscellaneous:
- Mishimoto aluminum radiator
- B&M fuel pressure regulator
- B&M fuel pressure gauge
- chipped P06 tuned on Neptune
- Walbro 255lph fuel pump

The peak wheel horsepower was 158 and the torque was 116. At face value this seems like only a minuscule improvement over the previous setup. It can easily be viewed that way if you only consider peak output. However the greatest improvements are across the entire RPM range. The is more torque at the bottom, a nice horsepower and torque bump at mid-range and it stays consistently above the previous setup before it falls flat on its face close to 8000 RPM.

I've attached the dyno chart with both the 2016 and current 2017 information:


Here's the video of the final run:
NA d16z6 dyno

At the end of the session we adjusted the cam-gear to see what could be done. As expected, retarding it resulted in a loss of power. We advanced it 1* and made the most power but I opted not to attempt advancing it any further - for now. I can't be certain that there won't be piston to valve impact if we go too far. The deck was milled and head was resurfaced on a P29 high compression motor. Maybe I'll be a little braver when we do the next tune with the injectors. I hope to break the 160whp ceiling with the addition of the injectors.

Building an NA d16 has been an incredible learning process. I plan on making a new thread about it to help inform other SOHC builders based on my experiences.

Here are some pics of the exhaust and the engine bay. I'll be getting a proper tip in the near future.

 

Nice work! It's a little hard to tell from the dyno sheet, but it looks like you gained 5-10whp throughout most of the powerband, is that correct?

 

Thanks!

Theres definitely an increase across the entire RPM between 5-10whp. The biggest noticeable increase is between 5000-6000RPM when VTEC is engaged. Peak power is almost the same but the output is increased where it matters the most which is throughout the entire pull.

The graph is a photo of the screen so not all the information is available. I'm getting the full data file from the tuner tomorrow.

 

sweet little motor nice numbers!!

 

Thanks!

 

nice numbers. do you ever take it to the drag strip? interested what your trap speed is.

 

Thanks!

I've never actually taken it to the drag strip. I tend to only bring it out for lapping days, time attack or autocross. I'm definitely curious though...

I find going fast around a corner more fun than in a straight line!