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.

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.

I'm using a Spartan 3, have used the early version with the analog output (as the canbus didnt work, so new later model one sent under warranty) and then with canbus. Both seemed crazy fast response time compared to 4.9 or 4.2 sensors. Not having to squish a range of results down to a 0-5v signal means you can get readings right out to 50:1 and incredibly rich as well. Which is sort of pointless, but when you're initially dialling in a tune it means it takes fewer steps to get to the right point. The best part though, is I'm still on my first and only LSU-ADV sensor. Where as I've probably got nearly a dozen blown up 4.2 and 4.9 sensors kicking around. Definitely an A+ rating for Spartan 3 from me. But make sure to get the LSU-ADV.

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.

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.

Hah! Good point. probably not.

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.

Sorted! Just 10mm further out and a 5mm drop and life is good. Probably dont need the 5mm drop. Now just need to go over my model with a fine tooth comb, and make sure everything's actually good with no weird geometry or whatever. Also, in testament to the fact that absolutely nothing on this engine wants to fit. I have to cut off the timing mark stand thing, to run the belt where it needs to go. FFS. haha. Hopefully this is the last in the series of punishing oil filter posts.

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.

Well its nearly there! Might need to be another 5 or 10mm further forward. Be good to drop it a little lower but im running out of thread depth. As the rear of the three holes sits on top of the gallery. Then I should be able to get the belt on/off with it in place. Need to remove the filter housing to take the pulley off, but thats probably only a task for major operations anyway. Can live with that.

I found a few more contenders for oil filter options. The 4 bolt mazda one was a bit too chunky, and the orientation of the galleries further limited options. Then thanks to @ajg193 for pointing out that the 4K oil filter housing looks like a good contender - then thanks to @chrisR who found me one at pickapart on a 7K powered van or something. Looking like a better option! A lot more compact, and has the oil pressure sensor on it. Only downside is that the oil inlet pipe is 13mm dia. Where as my main galleries are 18mm. Which ends up around half of the cross sectional area. Makes me a little nervous to commit to it. I did some more pickapart scouring. I found another one one from a Suzuki swift that looked good. 3 bolt flange, but seals with an o-ring instead of a gasket which makes life easier. And the fully circular inlet makes it easier to orient it on any angle. Also the inlets and outlets look plenty big. sweet. Looking fairly promising with a test fit, keeps it nicely out of the way. So I've modelled this up, then I am just printing a test piece of the front of sump to make sure it will clear everything. I'd rather not have to remove the oil filter housing every time I need to take the front pulley off, or fit a new belt. The outlets of the 4GR oil pump have 250mm2 outlet/inlet area each. This filter housing has 330mm2 for the center hole, and 450mm2 for the bean shaped thingy. That puts my mind at ease! Fingers crossed this all works, then can fire off a final version of the file to get the plate cut. Exciting! Will end up turning an 18kg plate into a 3kg final part.

Assuming my motor made 150whp in its final config (second dyno said 200whp which was... optimistic) Here's a comparison. I wonder if they've got the exhaust choked up badly. Seems like it hates the big cam until high rpm. Hopefully they keep developing it, and dont just call it a day after that dyno session!

Yeah that's fine, 4GR chat is a safe space to discuss shitty engines from other manufacturers too

Look for "Salinas speedway" on facebook. Some of the shit on there is absolutely wild. Puerto Rico drag racing visit is 100% on the bucket list.

Yeah might be a harsh dyno - or car might still need a bit more development. 2zz echos in puerto rico run 10 second quarter miles on a stock bottom end. Power levels of that car are similarish to my 1nz. But my motor was tapped out, that will have lots left in it! If it was staying at that power level though, id take the 1nz instead. Less weight, easier maintenance, much easier to replace a motor if needed. But if they commit to developing that car a bit more. It will be wild.

Found another option today. Suzuki swift. 3 bolt flange with bigger galleries and just an o-ring. Will compare options in a few days when back where car is.

@BiTurbo228 could you plz run the numbers on the 2mzfe and vq25hr ?

That or even a standard 5GR sounds good, however that also blows the budget (and engine replacement budget) completely to smithereens. 4GR = $700 replacement engine 2GR = $4000 replacement engine 5GR = $$$$$???? replacement engine or crank (only available in China) If the 5GR was more easily available, it would make sense as the best base to start from.

I'll never do a battery in boot again. I found the big cables to run a lithium battery to the boot, weigh more than the battery did. As close as practical to alternator and starter motor are the way to go I reckon. Then just make sure there's somewhere to clip on to recharge the battery or jump start the car if needed. Up under the dash can get fiddly

Yeah I dont think roller bearings will work for anything. As roller bearings on a crank are usually where the crank gets pressed together around the bearings I think? The rockers have roller bearings on them. Could always be made lighter though. Ceramic pistons is definitely not gonna happen but lighter/stronger rods and pistons should be easily achievable. Alright so ol mate @chris r was a GC and noticed a K series engine at Pickapart over the weekend. (I didnt think there would be anything K powered there! But late model liteace or whatever with a 7K) So he was kind enough to message me and ask if I wanted him to grab me the oil filter housing. I dont have it yet, but he took a measurement for me so I could scale the flange from a square on gasket drawing that I've got. So it's looking pretty good for fitting. Oil gallery drill holes are in red. The threaded holes for the flange have enough wall thickness away from the main pipes too. In terms of fitting it looks ideal, however I am a little concerned about oil feed pipe size. The 4GR oil pump outlet/inlet is 18mm dia, but the inlet on the K filter is 11mm. So it ends up around half of the cross sectional area. This motor runs all of the oil through the filter, no bypass. Then has 4x vvti pulleys, 6 oil squirters then all the other usual stuff to supply. So I'm a little concerned that it might be a bit of a restriction, but does anyone know if that's likely going to be an actual problem? I will go pull apart the standard 4GR filter assembly and see if it's got any bottlenecks in the filter housing. Since the plate the sump will be cut from is fairly spendy I'm not overly keen on getting this wrong. 4K setup is looking like an awesome solution so long as it will flow enough.

Yes, these motors are a bit like lego sets. There is the head, itself, then there's another layer up that holds the underside of the cams and rockers. Then cam caps bolt onto that. The 1GR engine, unlike the others is actually a valve on bucket engine. So, although it would be a bit of an engineering exercise. Not impossible to design a completely different cam/rocker arrangement that bolts on top of the head. However there are also some intermediate options like just designing some lighter rockers, or whatever.

Shimless buckets in the 1NZ. I think (?) rockers means you can have a more aggressive ramp rate as you're not limited by diameter of the bucket. But, on the whole the type of rockers present in GR motors seem to be troublesome / not ideal.

It was definitely interesting when I pulled the 1NZ apart and saw that the piston had ripped in half. Rather than the rods breaking which people usually do. (At much lower rpm, loading motor up with forced induction) I cant find any data on factory 1NZ piston weight. However JUN 1NZ pistons are 232 grams with the pin included! Not sure how much OEM ones are, but they also felt incredibly light. Well, at least the half of one that I was holding... Then the rods are tiny toothpicks as well. Looking through some logs it would bounce to 9200rpm when doing burnouts at the drags.

@BiTurbo228 the 4 cyl ducati that does 16500 rpm is something like 8000G.... but tiny tiny pistons so not really comparable

This is possibly the nerdiest thing I've ever seen. I guess what I'm trying to say is... Will you marry me? That's really cool data you've put together, well done. Will have a good look through this! I've not really considered bearing surfaces etc. Mainly because I'm completely ignorant on the topic. I guess it's unlikely that bearing area needs to squeeze up smaller than ideal, thanks to 4GR being dimensionally the same as a 2GR. With the 3500cc sized spacing between bores. It's got more room for bigger bearing surfaces and thicker crank in between, compared to a more regular 2500cc block of a straight six or whatever that's trying to be compact. So the crank weight is probably somewhere in between a compact 2500cc V6, and a 2500 compact straight six. Some interesting data points using your sheet. I think KPR has run both his long and short rod engines to 10k rpm, and they have identical stroke to my motor. Cant remember what pistons. But at 10k: KPR long rod motor is 5540 G, short rod motor is 5699 G. The VHT Racing Starlet's 4AGE runs to 11,000rpm with what I think is standard rod length, maybe a little longer. It's in a 4AGE block anyway, not 7A block. So even if they moved the piston pin up a bit, still wont be as good as KPR 7A block motor. A pretty extreme build with roller barrel throttles, liiiiiggghhhttt pistons and custom rods etc. But that's 6700 G. sheesh! Gets rebuilt a lot though I think. The 2500cc Alfa 155 DTM engine runs to 12,000rpm with a 61.3mm stroke, so that's around 6150 G assuming a 2:1 rod ratio. Obviously its a full blown race motor that' probably has a lifespan not much longer than a single race before everything gets rebuilt though. Extreme example. Ducati Panigale V4 R is a 4 cyl 1 litre engine that runs to 8500 G with a 48.4mm stroke and 16,500 rpm redline. But 250cc per cyl, obviously tiny pistons! So like you say, it's more about the G x the mass of the piston which tests the strength. Something else to consider about this 4GR project. Is that the valvetrain might absolutely 100% shit the bed at a much lower rpm than any of this carry on. And it might be an incurable problem. Stupid rockers! Either way, will be interesting. Haha. Buying a few blocks and making some parts to fix things that go boom is in the long term development budget. I really hope I dont fire anything out of the bonnet though, they're impossible to find these days.