Interesting. I’ll dig out that thread as a remap isn’t particularly scary. 6k isn’t a lot but running it to the redline just isn’t as sweet an experience as it should be in such a car.
I was recrunching the numbers from the measurements from the ported ND2 head.
running it through some software to get the sizes etc, and to calculate some flow numbers - it looks like the exhaust port is still too small for the flow being asked of it. *compared to the inlet potential.
But i also suspect the inlet manifold is going to be the issue. with its long runners its given a really (good) wide torque band, but just taps out at that top end.
might be useful data for someone else though for another project…
Although now i’ve got an itch….
do i go and grab the full nd2 bottom end, and get the lighter pistons and rods, get a lightweight flywheel and clutch and get it all balanced (thought probably not knife edged).
clutch is at 60k miles…. who knows how much life it has left.
ah but then im tying myself to the nd gearbox, and not leaving F.I options open….
however ‘‘perfecting the nd’’…. lighter nd2 componants at the bottom end, without the dual mas flywheel of the nd2… that sounds like perfection 
just oem parts, dont even need to go aftermarket. (flywheel the exception ofc).
is the Perfect ND one thats a streetable high power N/A engine, or a supercharged 300bhp+ monster?
Streetable for regular use in my opinion. While the megapowerboost might be fun for a while then personally I think 300bhp ish is just going to frustrate as you’ll never use it properly unless on a track.
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I think 300bhp reliably supercharged would feel lovely in the mid range. Reliably is the key though. I still bear the scars of my cold side supercharged NA, which is why I’m leaving my Super 200 well alone.
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thanks for imput guys
well im now 12 hours away from collection (sat in a pub in glouster now! yay).
i guess i’ll see how i get on with the 10 hour drive home, and see what sort of conversations i have with me and myself.
for N/A the £ to bhp now will be immense, with what ive had done.
But the ‘holy grail’ of beating the 240bhp S2000 legend…. is just 15bhp away. a full lightened bottom end (expensive) may grab me 5bhp. (ofc, this is free-d up hp, not actually hp generartion. but will register on a inertia dyno), could i find an estimated 10hp somewhere else without having to go ITBs….?
probably not….
i think i would have been so super happy if i hit 230bhp. thats my niggle. the fact ive just fallen short makes me feel ive got a silver medal, and gold is so close. and if ive got to ‘try again’ for 230, then why not aim for 240. ah the addiction
but i know Rodders got 260 full an ‘‘everything’ engine n/a. so whats left on the table really isnt much. (for my budget)
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I know the feeling as my 181bhp is just shy of 200. Luckily it’s brand new, still under warranty and nobody maps them so there’s no point messing with it. Yet 
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Updated my weight tables.
got as few blanks to fill.
but now for the first time - ive put some weight on! underbody mostly.
think its time for an anti-grav battery to try and slim a little lol.
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Bonnet
side glass/winders
carpet
roof
heater and matrix
stereo
you probably don’t need two windscreen wipers either
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haha, im not on a weight reduction plan. car is meant to ‘look’ pretty OEM. i just like to weight things as they come in / come off.
but ive missed a few - airbox, speakers are two that come to mind
Hadnt pposted about the car since getting it back.
having some teethng issues…
Alex has sent a few map variations but havent yet been able to fix issue at wide open throttle at top end.
Well - full and partial throttle (upto 6k) its pulling really well. its loud, its angry, it wants to go. At about 6k it has that kind of feeling of ‘‘coming on cam’, but then goes flat. followed by 1500rpm to redline of lots of noise, still accelerating, but you can feel the torque falling off.
been swapping some data files. but pput some into the ecutek suite (as i love spreadsheet at the best of times!).
chart below. Looks to me like torque curves are merging. (torque Desired being the ceiling arameter). once these merge, the ecu limits power by closing throttle.
This is annoying – this is exciting.
Annoying - because its not quite working as expected/wanted.
Exciting - if this was the behaviour on the dyno (every reason to believe it was the case)…. then 225bhp is not the ceiling. its currently capped
chart for fun. the green line is the Torque(Nm) the ecu is seeing/calculating.
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You may find that even if you uncapped it there would be a slight extra peak in revs at 6300ish but no more usable power produced. Get on a track somewhere and let the ECU learn its new strengths.
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i think you may have misread the yellow line at the bottom in relation? the yellow line should be constant horizonal, as my foot is to the floor (asking for 100% throttle). the ecu controls the actual opening. whats happening at the 6000 mark above, is the Torque Actual (how much power the car is making at a given RPM) is now trying to exceed Torque Desired (the map parameter which is calibrated / tuned / governed to control the amount of torque possible). As a result, the ECU is saying ‘‘you are not permitted to make more than X-amount of torque at this RPM’’, and its response is ‘‘i wil take your foot off the thottle for you’’, resulting in the yellow line at the bottom. Thats my throttle going from 100% (93% to be accurate) down to 54%!
throttle is half open.
Yeah my car will literally push back on the peddle if I floor it, it will get to about 4500 and the peddle rises an inch or two. It’s beyond optimum so there’s no point asking for more, staying at 4200 it will gradually increase the power without opening the throttle more.
My BMW had a second hp peak if I kept the throttle wide open but wouldn’t produce any more torque just burn fuel.
Hmm, I’m probably wrong here, but to my eyes that looks like some kind of restriction in the air system and the closed-loop feedback from the exhaust is reducing the fuelling to match.
Why do I say this?
I don’t like the look of your air intake, at least the one in the pic (post 42) with the weedy air cleaner on the left with the black tube across the front of the engine, and most especially not the little box on the end.
Basic rules of flow dynamics suggest the longer the pipe the greater its air resistance, and every bend effectively adds a lot more pipe, and the thinner the pipe the very much more its air resistance.
End-effects are also significant, if it’s making a rushing noise, usually because of a straight cut end, that’s turbulence which slows down the air - bell-mouth to the rescue.
Standing waves in the tube affect pressure points - think organ pipe. The ducts can be tuned for best top end, but that is usually quite short unless you can play with harmonics.
For a very brief yes/no test may I suggest trying it with nothing more than a smooth bell-mouth in front of the AFM.
If that makes a difference, then try adding a straight tube through the front wall to where the coolest air is, again with the bell-mouth.
If it’s simply the air cleaner limiting the flow, then try two of those drums in series to double their length, and therefore also the surface area for half the resistance.
I can see you’re having great fun, and its very entertaining watching from a distance without having to pay for it all!
happy to entertain haha.
i get your point on the intake. the length, diamater etc may well be causing restriction in relation to possible peak power at the target RPM we are at. (and i say ‘restriction’, in my phrasing of this i mean ‘‘less optimal’’ that alterntive designs, such as short intake runners) , but at the current juncture the issue is definitely in the ecu map, as we have the log files. also because the issue has been fixed by using an alternitive ‘method’ of mapping. (which made the car a pig to drive everywhere else in the rev range, but did confirm the top RPM issue was resolved. more power was made!)
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I think it’s load limiter that shuts the throttle can you raise the value?
OK OEM cams specs - as measured. (with electronic calipers. as accurate as i can manage). there may be 0.1mm of variance but shouldnt be more than that.
ND1 & ND2 Intake (same)
Valve lift: 6mm
258 deg duration
(not including VVT).
ND1 Exhaust
Valve lift: 4.9mm
241 deg duration
(not including VVT)
ND2 Exhaust
Valve lift: 5.3mm (+0.4mm)
254 deg duration (+13 deg)
(not including VVT)
ND1 valve sizes
In: 33.22mm
Ex: 27.94mm
ND2 valve sizes
In: 33.74mm (+0.52mm)
Ex: 28.59mm (+0.65mm)
now knowing this i can see why the aftermarker options typically need stiffer springs. they are adding about 5mm lift in aftermarket! wow.
** ECU MAP BREAKTHROUGH *
after some fun (serious, fun. i love troubleshooting car bits ) and thanks from @AdamR28 for some expert insight, weve found the correct table to update.
throttle is now staying open for the full RPM range.
with no other change - the ecutek based on its now seen Nm - we are now seeing an extra 7bhp at the top end!! thats back to back testing between 2 maps on the road. 5 minutes apart. the ‘improvement’ also had heat soak as i was rushed, which i can see in the midrange. i’ll get a good run tonight. i suspect it may be 8 or 9bhp up. (based on previous logs and temps)
this is a great result.
also this means, and discussing with Alex - theres some tweaking to be done now on the cam timing at the top end.
Currently we are running 74deg down to around 50deg in intake vvt. BUT, (based on my learnings, and factoring in our cam specs) this would typically promoting more valve overlap than optimal. in fact could be out by 15-20 deg at redline range…. oof.
so hopefully we will now just tweak the map to drop down to 40-something advance from about 6k, and 30-something from about 7k. and see how that improves on the road.
also - i need to get to a local dyno! I think weve smashed 225bhp!
*nerdy bit. Ecutek (or the Mazda ECU technically…) sees and calculates its airflow etc in Torque (Nm).
Once i export these logs, i can convert Nm to Lb-ft ( *0.7376). once i have the lbft, i can then do (Engine RPM x Engine Torque(lbft)) / 5252 = BHP.
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