Romans 2005 Toyota Echo

[Roman]

It's the same block, same rods, same head as the non hybrid version. Likely even softer valve springs but I'd need to change those in any case as the current 7200ish valve bounce limit is ruining my day.

But it has different pistons (high comp) and different cams (270 deg duration intake) to make it atkinson cycle.

Here's a pic of the factory pencil rods vs some considerably beefier looking aftermarket ones 



The upside though is that it's got a fairly decent rod/stroke ratio.
Which is probably why it can get away with such shit looking rods in the first place.

I've found a few more examples of people using prius pistons in normal 1NZ engines though. This dude had 140hp at the wheels and 8k rpm on standard rods.



In a toyota Vios though which is a big chunka compared to an Echo. 

Looks like it goes alright though
 

 

[ajg193]

I wonder what his curves look like below 2700 rpm

[Roman]

Probably better than the graph implies, as that's likely rolling onto the throttle there rather than it's full power. 

I'm more wondering why he's not revving it even higher, would lift his average power on gear changes (answer: factory rods. haha)

[GARDRB]

Found you a towcar, now you can go full retard

https://www.trademe.co.nz/a/motors/cars/toyota/listing/2853358239?bof=bj5myTLZ 

[Roman]

I dont understand what's going on in that auction? 

What's it got to do with a Vitz? 

All I see is pictures of a cyber truck 

[Roman]

One's got a light bar 

[GARDRB]

Pretty sure they've lusted after a vitz for so long that they put the interior from one into their cybertruck

[Spencer]

Those headers are going to be sweet. Whats the exhaust plan? you should do it for sure.

[Roman]

Ahhh not sure yet. Definitely bang the headers in but not sure if I'll be able to do the full rest of it before drag day.
It'll probably not acheive much without the rest to go with it though. 

I finally got consent for my shed so hoping it'll be up by christmas or not too long after. So some busy weekends ahead! 
And otherwise a bit tight on cash till end of the year at least.

Once I've got shed up there's no reason not to hoard more stuff for a C56 & big block swap instead of doing other stupid stuff like getting Carina going. 

[cletus]

Unbolt exhaust at the headers for drags? It's what a proper drag car would do

 

And by proper drag car I mean a HQ with a tired 350/th350/2.75 geared single spinner 9 inch with a badly jetted 600 holley and one of those fake 3 hole scoops thru the bonnet and some rusty chrome rocker covers and an accel super coil and a moroso sticker and a jack daniels towel over the ripped rear seat top and a wildcat steering wheel with the center cap missing  and a sticker on the back window that says only milk and juice comes in 2l 

[Roman]

My bendy trumpets wouldnt work, because if I try fit them closer over towards the edge of the engine bay they hit the bonnet. 

Based on some of KPRs wizard magic testing though, I saw that the effective tuned length seems to be where the end of the trumpet starts to flare out from its normal diameter rather than the outer part of the bell shape. So I figure since I'm probably not taxing the throughput of a 48mm ID I'll try keep it more uniformly shaped with less of a bell on it so I can fit the longest possible effective length with straight-ish runners and still clearance to bonnet etc.

Could have actually fitted a bit longer, but anyway, they ended up like so:



Looking at the fuel map it looks like there was nothing in it at all, like + - 1% margin of error.
Apart from it eating shit over 6000rpm and running rich.  Probably thanks to shitty bell entrance.
Again this is probably an instance where if the exhaust had less back pressure and I was able to make better use of the inlet and exhaust working together with cam overlap, you'd see more of a change wiith intake side stuff like this.

The other ones look to still be the winner at the moment though.
 

 

[Roman]

So I hooked up a MAP sensor to a single runner, and as expected it's useless because the voltage fluctuates like crazy. 

But then its interesting to view with an oscilliscope instead. 

This is the MAP signal when the car is idling normally. Peak to peak is 720 degrees of engine rotation



So when the intake valves are open and the piston goes down you can see pressure starts dropping as you'd expect.

Look what happens when you add 40 deg intake cam advance though. 
 

Now there's a period of time where the inlet cam and the exhaust cam are both holding their sets of valves open. 
So the intake side intake low pressure and the exhaust side high pressure means exhaust gas scoots right back over the piston and rushes to fill in the intake. So pressure goes up.
Then the exhaust valves shut, piston goes down and then the pressure starts to drop like normal. 
Which is why you get that fully sick 3/4 race cam idle on your 4k that goes hard for what it is.
I wonder if it's actually better economy having this happen so you're heating the air fuel mix. Hah.
I'll hook up some more sensors to it to give some context and see if there's anything interesting happening at full throttle.

[ajg193]

Big (not huge) cam in my 4k doubled idle fuel consumption.

[Roman]

Did you play around with injector timing at all? 

You could try set end of injection to say 240 BTDC and might mitigate fuel blowback issues 

EDIT: Oh yeah it's gonna be a lot worse if you have a plenum and also batch fire injectors.

[fuel]

On 07/11/2020 at 04:56, Roman said:

It's the same block, same rods, same head as the non hybrid version. Likely even softer valve springs but I'd need to change those in any case as the current 7200ish valve bounce limit is ruining my day.

But it has different pistons (high comp) and different cams (270 deg duration intake) to make it atkinson cycle.

Here's a pic of the factory pencil rods vs some considerably beefier looking aftermarket ones 



The upside though is that it's got a fairly decent rod/stroke ratio.
Which is probably why it can get away with such shit looking rods in the first place.

I've found a few more examples of people using prius pistons in normal 1NZ engines though. This dude had 140hp at the wheels and 8k rpm on standard rods.



In a toyota Vios though which is a big chunka compared to an Echo. 

Looks like it goes alright though
 

 

So when are you selling up and getting a Proton Saga? Would be interesting to see what has been done to that lead car, that original 4G15 would probably move like that!

[ajg193]

17 hours ago, Roman said:

Did you play around with injector timing at all? 

You could try set end of injection to say 240 BTDC and might mitigate fuel blowback issues 

EDIT: Oh yeah it's gonna be a lot worse if you have a plenum and also batch fire injectors.

I can somewhat time the injectors, but they still have to fire twice per cycle as only two drivers with microsquirt

I was going to adjust the injection timing but couldn't cope with the low oil pressure so ended up swapping the cam at same time as crank grind.

Interesting thing is that the new cam uses less fuel at idle than the factory one, about 8 cc/min when warmed up

Could just be that the engine is less worn out now though

[Yowzer]

Isn't there an add-on board for the micro that gives you four inj drivers? Probably worth looking into.

[ajg193]

https://www.msextra.com/forums/viewtopic.php?f=101&t=68504

Supposedly possible to modify one, just strongly advised against doing so. Requires cutting traces on the board and doing some other bodges.

It would be interesting to see if there would be much difference in how the car performs, but it's just a 4K so the improvements wouldn't be much

[Roman]

12 hours ago, fuel said:

So when are you selling up and getting a Proton Saga? Would be interesting to see what has been done to that lead car, that original 4G15 would probably move like that!

This thread is going to get real busy if people start listing all of the motors that are better than a 2NZFE

[Muncie]

Ooh ooh how about one of these in there for next drag day.