Hi. Another OzHonda noob here. Thought this would be a good place to write about my B16A numbers when I had a working EG6 rally car along with some dyno sheets.
Just ignore my writing on the graphs. All runs were done over the years with Ed at Autotech here in Canberra on their Dyno Dynamics dyno. They upgraded to a different 4WD Dyno Dynamics around 2010 I think. My apologises for the fact that the graphs aren't in shoot out mode. Lastly, all runs were done on the same set of rally tyres. Not the best thing for gripping on a dyno and probably why the numbers read a lot lower than I expected. We ran a friends B16B rally car on the same dyno on the same dyno, changing from rally to worn road tyres and it went from 91kw to 105kw atw! Another guy with a different rally car has seen rally to road tyres knocking 1kw off the peak power though.
Anyway:
I hope these numbers all help some people who are looking at mods.
Setup 1:
I started off with it in standard OEM spec, just with Jasma extractors that it came with and dirty exhaust. Exhaust was some 2" piece of junk that had squashed down to 1" in one spot. It didn't make a difference. ~95kw
...then we removed the air filter for a 'best case' scenario:
Another nice 4kw atw from having no air filter was suprising. We tried advancing the dizzy at the time but it made no difference. Honda certainly built these engines well.
Setup 2:
I brought some OBX quads from the US, put air filter socks on them. Also replaced the exhaust with a nice 2.5" all the way through with a single hot dog and 2.5" straight thru muffler and tip. Went the 'Crome' route on the ECU myself just aiming for 13:1 on the A:FR at WOT. I also changed the gearbox to a Team MFactory one, with 4.875:1 Final Drive, and short ratio 3,4,5th at this point. Max speed was 175kph at 8,300 I think. 5,000rpm at 100kph down the high way was kind of noisy.
End result: 105-106kw atw:
Here's the same picture with the AFRs on it. And, from the time, my own estimation of the original 95kw run. Basically, it felt like the quads moved the power curve to come in about 800 rpm earlier. So much nicer to drive basically.
After a season of rallying and wearing the engine out a bit, it was down to 103kw atw.
I organised a dyno day and had the chance to run my car with a 2" straight through muffler versus a 2.5" muffler. Difference: 2kw atw...if you're interested.
Setup 3:
Time to get serious to try and give the turbo 4WDs a run for their money.
So, I used an EFI Hardware.com airbox to put around the quads, then had to extend it to keep the fuel injectors inside the box. 4" flexi pipe feeding it.
Mahle 11.5:1 C/R pistons.
Supertech valve springs.
4:1 eBay replica extractors based on the PLM B series extractors. Awesome looking set.
Davies Craig Electric Water Pump with mechanical water pump removal plate.
Red lines are the old readings from the worn Quads from Setup 2.
End result: 114kw
Here's the torque curve. About 15% more torque higher up.
Setup 4:
Unfortunately in doing Setup 3, I managed to cook the engine mainly because the radiator fan didn't come on initially. Big fail. As part of the diagnostic process, I removed the electric water pump and put the mechanical back in....
Blue line is the mechanical, Red is the Electric Water Pump.
End result: 110kw:
The graph above doesn't strike me as quite right as the blue curve shouldn't be to the left of the red (superior) curve. Fuel, tyre pressure, who knows. We hadn't changed the ignition curve between the two setups.
Yeah, Allmtr996, you are right - the AFRs aren't the prettiest down low in particular. It was really cost of the dyno time, and I only probably needed to add in a few more rpm mapping points in Crome, and in competition anything less than 5,200rpm is generally time to knock it down a gear. I wished I had the time to get it nice and smooth and get a few more kws out of the mid range consequently.
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It sucks it squeezes it bangs it blows 
It was really cost of the dyno time, and I only probably needed to add in a few more rpm mapping points in Crome, and in competition anything less than 5,200rpm is generally time to knock it down a gear. I wished I had the time to get it nice and smooth and get a few more kws out of the mid range consequently.
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