Roman's 4GR V6 Carina discussion thread

[h4nd]

Nice, sneak it lower and put a nut / weld a captive nut to the underside?

- oh thread for the oil hole blocks. As you were.

Might want a sharper front corner for oil line sealing surfaces? *1. 

(Ignore*2, I figured it out, you clever man!)

[Roman]

That outer red line in the picture is the outside edge of the O ring which seals it.

Those two holes in the front end up getting plugged back up. Either screw in a grub screw like oem stuff does, or maybe weld a plug in.

Its just the position of where it needs the oil gallery drilled. So that radius wont affect sealing at all.

[Goat]

55 minutes ago, Roman said:

Hopefully this is the last in the series of punishing oil filter posts. 

None of your updates are punishing. They're all super enjoyable to read.

Love what you do. Don't change. hah.

[ajg193]

Is it too late to use the old timing mark to make an alternative mark on the other side?

Edit: I guess you can use the timing belt alignment marks to clock up the crank pulley and then pick an arbitrary point to mark

[xsspeed]

Whats that idler doing, can you move that to the right to open the angle up

[Roman]

Yeah its easy to just reindex the timing mark. 

Just set the motor to TDC on #1 and then mark both the pulley and the timing cover at some point that's easy to point the gun at.
Not really a big issue with the timing mark, it's just what you put a timing light on. Not the mark for setting the chain.
So you can just put a new mark on the pulley and something close to it at any position.No drama. 

For the belt, I'm now only going to be running the alternator (pulley 7) and the waterpump (pulley 3) as accessories.
Then pulley 2 is a hydraulic tensioner, number 6 is a static idler.
So there are a few options for the belt path and how tensioner might work.

I'm thinking the top left option is probably the best, as I get the most belt wrap on everything. Could maybe go without the #6 idler. 
Bottom left would be minimal path, least belt wrap, probably flap around a lot and need to be pinged up super tight.

But either way, if I'm not running the belt around #8 (aircon I think) then I need to chop that timing mark.

[xsspeed]

Is bottom left feasible for tensioner to work other way?

[Roman]

Hah! Good point. probably not. 
 

[Themi]

Apologies if it has been discussed already in the last 17 pages but a quick ctrl+f didn't find it.

Regarding DBW control - RusEFI boards have open source DBW hardware and firmware available for you to look at. I mean I'd suggest getting some proteus boards manufactured (including 2 for me ) however component shortages are a right pain. The Proteus handles dual-DBW so the hardware/schematic could be taken from that repo, and to control it perhaps picking apart the rusefi firmware would be the way to go.

https://github.com/rusefi/rusefi/blob/master/firmware/controllers/actuators/electronic_throttle.cpp

https://github.com/mck1117/proteus

[Roman]

Ahh yeah I got the e-throttle stuff working a while back @Themi.
I decided I will use one bank with the onboard e-throttle, then second bank controlled over canbus. Rather than both over canbus. 
Reason being that if my setup shits itself, I can still limp somewhere with one bank running. 
But not if both are being controlled by the same external device. 

I've still been trying to find the right plugs for e-throttle. 
It looked like the 2 pin ethrottle plug was the same as the mazda RX7 IACV or the Toyota radio filter. 
However it's the right shape etc but just slightly too small of a plug. 
Then the plug I bought for the 6 pin TPS didnt work either. 
Think I will just change it over to another 4 pin TPS instead that I've got plugs for.

[Roman]

Ahh man I have been going 7 days a week plastering and painting my house outside of work hours. 
Which I think has taken a toll on my levels of brain juice for working on car stuff.

As today I cut off the timing stand thingy - which was hollow so now there's a hole to patch in the timing cover. 
Then I couldnt figure out why the tensioner wasnt going to work at all. Because I was trying to run the belt the wrong way.
So I took the tensioner off and had a look for how it might run without it.
I could probably just tension it by pushing the alternator into its proper place. (With the correct length belt - This one slightly too short) 
Which means I didnt actually need to cut off my timing mark. 
Also I bought a 6PK belt when it's a 7PK. (wtf does it need 7PK for?!)

If I can run it without the tensioner that would be good, for sake of a 2kg weight saving.
But I think I need a decent rest before doing any more brain based activities. 



 

[kpr]

might be able to change that idler pulley to an eccentric type one,  to get belt adjustment

[shrike]

Assuming your going to tig up the hole? I have the feeling its not going to be a fun job

[Roman]

If the belt path works like that, I'll just get another front cover so I get the timing mark back.

Ahh yeah an eccentric idler pulley looks like a good scheme. Will see what I can find. 
 

[Spencer]

 Belt seems legit like that, new cover and yeah some kind of adjustment on that idler and its done. Keeping those timing marks will be nice.

[Roman]

It's amazing how grippy even the PK6 is on there - if I turn the alternator pulley, it is holding on well enough to turn the crank (heads off though, so no compression) 

However I dont think it would need a huge amount of belt tension to work well. 

Currently has a PK61035 on there, have ordered a PK71080.

Hopefully that'll be long enough to get the alternator bolted on correctly, either with a smidge of tension or slightly loose.

It still cracks me up that with the 1NZ motor, the belt tensioning system is basically "Put a bar behind the alternator, pull the belt tight, do up the alternator" haha. No tensioner at all.

1NZ is a masterpiece of irreducible complexity.

[Roman]

Something else semi worthy of noting. 

Usually the go-to for loom plugs is DT or DT mini, but it annoys me that they have their own terminals separate to everything else on a Toyota loom. And they look a bit out of place.
Then if you need a few plugs in the same place, there's risk of mixing them up and plugging wrong thing into the wrong thing.  (True for any type of plug though)
I found some Sumitomo plugs that use the same terminals as everything else on a Toyota loom. Ordered a bunch of 12 way and 16 way plugs to make a detachable loom from the motor. 
So if you used 2x 12 way and 2x 16way, and reversed the male and female sides on each of the same plugs. Then you've got 56 pins with no chance of plugging in anything incorrectly. 

https://www.aliexpress.com/item/1005001608539293.html?spm=a2g0o.order_detail.order_detail_item.3.26e5f19c0cNfX9

[Roman]

Some off topic V6 sharns. 

Looking at history of the Alfa 155 DTM motor. 
The rules said they needed the bore spacing and bore centerline of a factory built engine.
Originally they had to stick with the spec from factory motor which was 60 degree bank V6 busso engine. So this is how it was for the first few years.
This was a problem because the spacing and vee angle means the V6 has one crank journal per conrod, and counterweights for each rod.
They wanted something lighter and more compact. 
So later they bent the rules to say that they were using bore size and spacing of one of the 90 degree vee V8 engines.

I have been scratching my head as to why they wanted a 90 degree vee.
Turns out the benefit was that they could fit two conrods on a single crank journal.
So the bore offset between left and right banks is reduced.
The crank weighs a lot less with simpler counterweights.
Then the block and everything else weighs less as it's more compact. 
Which is part of how they made it 50kg lighter than the busso v6. (110kg)

[BiTurbo228]

Yeah a lot of people think the 155 DTM engine is a Busso and it's got nothing to do with it at all. The homologation is for a PRV (IIRC) that came in the Lancia Thema V6 via that Fiat/Saab/Lancia/Alfa joint big saloon project that gave us the 164 and the Saab 9000.

[Roman]

I initially thought they wanted to usr the v8 spec to get a wider bore spacing, to fit a bigger bore and shorter stroke.

But was surprised to read it actually pushed the cyls a lot closer together.

But makes sense. The motor had to hang way in front of the axle line because of the 4wd system. 

It would have sledged like a bastard if it was a heavy engine.

Im lucky to be able to fit a fair chunk of the weight behind the front axle line.