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About 3 years of DD on my ITBs...stock OBD2 ecu with piggy. Instant starts year round, excellent MPG (mid 40s highway), runs hard, runs cool in traffic. Built motor. I don't do copy-builds tho, if you do that...what I accomplished is impossible.

https://vimeo.com/279183657
 

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My 1.6 Aizawa setup made 124HP @ATW on a "very cynical dyno". 148 Flywheel? Horsepower.

Interestingly I've put in spacers and they've made a meaningful difference, valleys become hills:



Red is 50MM Trumpets + ITG JC40/65 Filter
Green is 50MM Trumpets + 50MM Spacers + ITG JC40/65 Filter


Wow, very nice, thank you.
 

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About 3 years of DD on my ITBs...stock OBD2 ecu with piggy. Instant starts year round, excellent MPG (mid 40s highway), runs hard, runs cool in traffic. Built motor. I don't do copy-builds tho, if you do that...what I accomplished is impossible.

https://vimeo.com/279183657
That sounds fantastic. NA builds I know can be difficult to replicate, especially with unique parts. It’s nice to know know goals though. Those are some killer MPG’s too!
 

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I don't believe the mid-40's highway number.

At all.
Perfectly fine with me.

ND miatas can do the same range of MPG at cruise! There is no reason a tiny / light car cannot do better than the usual lower 30s MPG stock can do you know. My car is at 2180# ATM.

The engine build is not stock, it's much more in the direction of MODERN engines now. Long list of changes.

It also runs very cool between the reroute and full internal coatings. A stock radiator, one fan is used...in NC (hot). The radiator has about 4 inches of core removed as my intake goes straight through where that section would have been. It can be made smaller.

Folks, don't just copy something you saw on YouTube or IG. If you do, you can ONLY achieve whatever results they did. And lotta video project cars may not have been done all that well. So..why copy them?!??!

For instance you don't need those octopus vacuum blocks. I just used an 8 dollar air manifold glued onto the ITB adapter, and event that is overkill in some ways.

Same with running MAF and a stock ECU (with piggy). I'm told that cannot be done. Open stacks..megasquirt (yuck) are the copied way. LOL, not only can it be done but it is easier and simpler to do so. it's the OEM way too. I went for a ride after the first startup. Needed tweaking but was at least operable.
 

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The BP is an inefficient lump that struggled to break 30 MPG when new.

You aren't getting 50% more than that unless you're in neutral downhill and/or run dangerously lean.
 

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Google me.
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The BP is an inefficient lump that struggled to break 30 MPG when new.

You aren't getting 50% more than that unless you're in neutral downhill and/or run dangerously lean.
Read this Tamale:

https://www.reddit.com/r/Miata/comments/4g0p3u/nd_owners_real_world_mpg/

And this...in the MPG section they note a 50% increase from the ND over the NC:

http://kaizen-factor.com/nc-vs-nd-evolution-mazda-mx-5-miata/

My engine is still a BP, but it is far from stock. It's much more towards modern engine ideas, such as Mazda's skyactiv. No need to just copy what other owners of older miatas have done, locking in the old ways etc?

For instance my compression is sky high, plus some tricky build changes to help that work better. And things like ported oil and water systems (cuts pumping losses). Resonance tuning on both the intake and exhaust sides, coordinated. 5# alternator with a fraction of the rotating inertia of stock, yet cheap and plugs right in. On and on, it adds up. BBFW spoiler laid down cuts aero drag, car needs better front aero however. With better front aero and Prius tires I wonder what it could do...possibly break 50 mpg.

So..I got my old lighter than a stock NA or ND miata...to do ND-like MPG.

The folks doing ITBs on earlier miata and fussing with wonky standalones sorta tuned and settling for a 1300 rpm idle etc and 20 mpg...are just doing it all wrong in my view.
 

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Google me.
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You posting links to ND fuel economy does nothing to prove your own claims.
Don't know what to tell you.

Mazda gets 40s mpg out of the ND, per many owners.

It can be done in other cars too, but NOT by doing stock / copycat builds.

That's the part you seem to be missing.

I have not copied, and did all sorts of innovative things to the motor.

It's much more modern in various ways now.

Heck I invented that camera mount too (from the video), long ago.

You can do the same, but it is up to you.
 

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Here's a cool thing I also did. With plenumed ITB stacks and the actual air intake in front of the radiator...the musical tones are faint.

So, I added a diaphragm-ed tube connecting from the plenum...into the car's ventilation system. By playing with the membrane and orifices you can tune both the tone and loudness to taste.

Works great, and you can hear it in most of my videos. This is back when I had Ohlins, which you can spot lower right. Now the car has Xida ACE semi-active, alloy drop spindles, alloy arms, spherical bearings instead of rubber or poly bushes, etc.

https://clubroadster.net/vb_forum/styles/redcarbon/attach/jpg.gif
 

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Google me.
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Why don't post a full build thread then? I am sure it is going to generate some discussion.
Not really into that, too many Hot Tamales. Not enough time etc. One thing you realize (if you are creative), is that it can bother people.

Main thing I can tell ya is to try things out, put down your Galaxy or iPhone and avoid copying things if you want new results. Instead work off of basic principles and trying things out.

Like my 4 pound (could go down to 2-3#) axle back muffler with zero drone and street / track capability. At some RPMs it has below zero back pressure.
 

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I am curious to know what this cheap, easy plug in, less inertia alternator you have is.
One of the mini alternator variations drops right onto the car and matches electrically (all wires). Stock, unaltered mounts and stock but now shortened adjuster. I have the thing tucked up to the block tight so I shortened the adjuster. More working room, helps with a filter change for instance. I run a 3 instead of 4 rib belt to cut losses. The now solo rad-fan blows onto it (alts like cooling too), slightly offset since i have the intake going thru what was the passenger-side-most region of the radiator.

On inertia, remember that for rotating masses, the distance from the centerline is important. With the lighter parts moved significantly inward the rotational moment of inertia is reduced.

You can do a simple test to see what I mean. If i take a stock and a minitalternator that are both broken in (much lower brush drag) and turn them back and forth by hand you can feel how much easier the little guy moves. It is quite apparent.

Now factor in that alternators spin at a multiple of engine RPM. Large pulley turning a small pulley. This amplifies inertial factors.
 

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Murse Magnet
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One of the mini alternator variations drops right onto the car and matches electrically (all wires). Stock, unaltered mounts and stock but now shortened adjuster. I have the thing tucked up to the block tight so I shortened the adjuster. More working room, helps with a filter change for instance. I run a 3 instead of 4 rib belt to cut losses. The now solo rad-fan blows onto it (alts like cooling too), slightly offset since i have the intake going thru what was the passenger-side-most region of the radiator.

Interesting, happen to know the amperage? I've been looking into slightly higher power alternators.
 

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Interesting, happen to know the amperage? I've been looking into slightly higher power alternators.
I have a few, one measured 75-76, the other 72-73 amps per the test sheets. So not a bump from stock. i don't run a system or even AC, power windows, etc. Solar with controller for when the car sits off season.

I use a lithium iron battery (light and super fast cranking) and they like a bit more voltage than a conventional lead acid. Car runs fine either way, but to get full capacity and the benefit in other areas of the car from a bit more V I made accommodations for that. i want to add a separate voltage sense lead back to the battery (stock trunk location). But I will wind up moving it (since so light) to live ahead of the starter and behind the alternator. Saves some more wire / weight.

The little alternators work great altho I broke a brush at an autocross recently. Made it home on the tiny battery alone, good test. Had that fixed for 4 dollars locally at a repair place. It turns out that when the far end of the copper braid was soldered in China...this was done wrong and so too much went up the braid. Leaving just a short section to flex since solder does not flex and so the braid broke in about a year. Bought a spare brush pack too for the tool kit, they are easy to change out, nearly an on-car thing.
 

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Murse Magnet
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Happen to have a part number for the alternator? I am interested in reading more up on it and maybe swapping out mine.
 

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Google me.
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Happen to have a part number for the alternator? I am interested in reading more up on it and maybe swapping out mine.
I do but I am holding onto that. Nobody else has found it in all of these years, and they do odd mounts, or use crappy one wire setups, and similar that I would not tolerate.
 

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You're literally making words up.
No it is literally four pounds using thick wall mild steel. Would be less out of SS or alum. It has two silencing components, one of which is a large but tailored-Q branch resonator. At certain frequencies (rpms) and loads it dips below 0 psi. It's an acoustic cancellation effect. This is coordinated with the 3 on the intake side. The stock branch resonators on miatas and other car's intakes provides a mild acoustic supercharging effect easily seen on a dyno. There are ways to increase and broaden that effect, but you have to watch out for side effects such as lag. Or less accurate MAF signals, this can all be sorted however.
 
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