Romans COD piece

[HighLUX]

So much science and wizardry I dont understand

 

Must be a dave thing

[Roman]

Sorry I get a bit rambly sometimes, will make the next update something interesting like hopefully some trackday footage!

[Vintage Grumble]

Bro, cold air intakes are the biz, I had one like your's on my first AE101, and the intake tube would condensate, and the manifold would be cold to the touch rite up to the head. Its a good idea to not have any form of scoop out the front tho (unless its high up) the amount of stones/sand/birds/tree that ended up in my caribs air box was ridiculous, and it only had a 3" bit of tube sticking out the front.

[shaneo]

^{I need to build one for mine . I wonder if I have time ??? but I dont have room. Keen to see this on the drag strip}

[Roman]

Bro, cold air intakes are the biz, I had one like your's on my first AE101, and the intake tube would condensate, and the manifold would be cold to the touch rite up to the head. Its a good idea to not have any form of scoop out the front tho (unless its high up) the amount of stones/sand/birds/tree that ended up in my caribs air box was ridiculous, and it only had a 3" bit of tube sticking out the front.

 

Yeah even when the airbox was pulling air from the engine bay, my air filter had bugs and twigs and all sorts in it!

This isnt *directly* in the airflow because it's tucked behind that lower valance thingy. So hopefully that stops most of the road kill reaching the filter

 

 

^{I need to build one for mine . I wonder if I have time ??? but I dont have room. Keen to see this on the drag strip}

Yeah I'm looking forward to the drags! Main problem though is miserable traction off the line, unless I can be bothered making some traction brackets in the next week or two it will probably be stuck in high 15s.

[bigfoot]

I will likely be lacking traction too(aiming for high15s)

[shaneo]

you guys are super fast I'm hoping for high 17 for my little engine

[tim13]

so , you may have this covered , but ; if your air intake goes up what was the fuel system doing ? if lean that could explain pinking and knock sensor pulls timing causing power drop as a result ?

EDIT , have noticed thats air-mass not power on that graph , same test with a bigger pipe would be interesting ...... you may have that sussed though

[Roman]

Yeah its just an air mass graph but in order to make more power, you need more air so they go reasonably hand in hand.

On a previous engine I had an apexi pod filter setup with a really nice pipe back to the throttle body. Dynoed at 150hp at the wheels, with a horrific loss of low rpm power.

 

I eventually found a factory airbox so fitted that... Dynoed at 170hp at the wheels with a whole heap more low/mid range power.

 

but no one had figured out how to datalog the factory ECUs back then, so thought I'd try again to see why.

The MAF sensor needs to be fitted in the correct size pipe though, cant go bigger or it would definitely make the engine run lean.

 

But yes, there are three possibilities here - one is that the engine is sucking in way less air, so lower readings.

 

One is that there is turbulence or something causing the MAF sensor to read a lot lower.

The third option is that there's turbulence or something that causes the MAF to read lower, AND less air to suck through.

 

Based on the way the curve has changed though I'm guessing it's an airflow / tuned length issue though rather than solely a MAF problem, as otherwise I wouldnt expect the 'dip' to move up or down the powerband.

 

I guess the way to isolate it is to try again with a different length of pipe on.

 

If the readings stay about the same, it's likely a MAF signal issue.

Thinking about it some more I am a bit skeptical that a tuned length before the throttle body could make so much difference, but I dont see why the MAF readings would be so much lower than with an airbox.
 

[tim13]

I meant bigger pipe except air flow meter , if the afm is the main restricter in the system bigger pipes pre and post should still flow more than same size throughout , fascinating stuff though , always nice to see a good reality/theory balance

[Roman]

I cant wait to get a tunable ECU one day and just be able to adjust the damn thing instead of playing around with smoke and mirrors hahaha.

 

But there are still useful ways I can analyze physical changes to the motor, which is cool!
 

Dyno time is expensive so it's good to have other options for tinkering and seeing what works etc.

I guess I can buy a wideband in the meantime, and run it in parallel with the narrowband. 
That would have definitely answered the question today as to whether it was a MAF signal or lack of air causing the difference.

[tim13]

everyone works to a budget the size does vary though ! I have always tried to maximize results using stock/cheap parts with some success , I used to judge "improvements" with a third gear run between two points (in and out a tunnel) if I always entered at the same speed and floored it my exit speed was up or down dependant on the "improvement" (I picked up more than 10kph in my old fxgt)

[Roman]

Yeah I've got a good GPS unit that I can use to measure gear pulls or whatever too, but I only ever really use it on the racetrack where I can measure consistent results in a similar way...

 

I find if going along random stretches of motorway or whatever, a slight dip or rise in the road can make just as much difference as anything else so it seems too tricky to get meaningful results. Where as a scatter plot of MAF readings or temps or whatever, you can accumulate data over multiple runs to verify your findings a little more thoroughly.

 

Drag racing is a cheap form of dyno though, at the Oldschool drags day it ended up costing me about $5 per run down the strip

 

I didnt make any changes on the day, but if going to a similar event with a few different intakes to try or whatever is a pretty good way to measure 3rd gear pulls etc.

[BlownCorona]

now thats the real chart that needs to go on pod filter boxs! 

[mjrstar]

Hey with the ecu logging you are doing you should be able to drag out a csv file and drop it into virtual dyno? (Freeware download)

Its good for tracking down how the engine is delivering torque..

[Brennan]

What if you had a Arduino or similar, and use it to measure the speed at which you are accelerating through each gear.

And then turns on the shift light, at what ever RPM it calculates the shift light needs to be switched on?

 

don't ask me how haha. but it sounds plausible to me???

[Roman]

Yeah that sounds feasible and a more elegant solution!

but im not smart enough with electronics to figure that out and it would be a bit spendier than using a few $11 shift lights.

Will see how it goes when they turn up

[Brennan]

Arduino are surprisingly cheap. But you would spend days nutting out the programming.

With the 4 shift lights; they aren't going to know which gear your in are they? So all 4 will be lighting up at slightly different times and you just need to remember which gear is to which light?

Also interesting that you say link ecu's have this feature already. I had no idea and will have to look into that.

[Roman]

At taupo or hampton i never use 1st so 2 lights would probably do.

One for the 2nd to 3rd gearchange and other for the rest.

But at the drags the 1st gear change is critical as well as launch rpm.

So could set one to 3k rpm or whatever so i know what to aim for.

If it turns out that using just 1 is just as good as anything then ill stick with that. But they were cheap enough that buying a few extra wasnt the end of the world!

But yeah the idea would be that all 4 light up.

Same as those progressive shift lights that start lighting up approaching redline. But this way i can set each light as i please.

[Rookie]

But at the drags the 1st gear change is critical as well as launch rpm.

So could set one to 3k rpm or whatever so i know what to aim for.

 

 

Sounds like you need a 2 step button...