Sound of a forged 2ZZ engine

[AJRFulton]

Just rebuilt my engine.

I'm running (at least) 12.6 compression ratio (12.3 Mahle pistons with +0.3 MWR flat faced valves) - the head has also been skimmed, so the compression ratio may well be in the region of 12.7-12.8.

Also running MWR springs and Piper Stage 3 cams on the head (although my 2ZZ's have always had springs and cams - so tuned to what they sound like) and Carillo H beam rods.

My question - what exactly should the engine sound like when compared to the standard 2ZZGE

The engine has not been mapped or run in properly yet.

My observations - Knock value on the Apexi has increased slightly - on a good OEM engine at idle this would be 5-10, and maybe be about 20-30 at revs. I'm seeing an idle of 10-15 and 30+ at revs.

The engine also makes a ticking sound. I can best describe it as a similar sound to what the 2.2 diesel engine in my transit makes at idle. It isn't an unpleasant sound, just a different sound.

I've never really been around too many forged engines, or ever seen a forged 2ZZ - so wondering what it should sound like.

[1979scotte]

Just rebuilt my engine.

I'm running (at least) 12.6 compression ratio (12.3 Mahle pistons with +0.3 MWR flat faced valves) - the head has also been skimmed, so the compression ratio may well be in the region of 12.7-12.8.

Also running MWR springs and Piper Stage 3 cams on the head (although my 2ZZ's have always had springs and cams - so tuned to what they sound like) and Carillo H beam rods.

My question - what exactly should the engine sound like when compared to the standard 2ZZGE

The engine has not been mapped or run in properly yet.

My observations - Knock value on the Apexi has increased slightly - on a good OEM engine at idle this would be 5-10, and maybe be about 20-30 at revs. I'm seeing an idle of 10-15 and 30+ at revs.

The engine also makes a ticking sound. I can best describe it as a similar sound to what the 2.2 diesel engine in my transit makes at idle. It isn't an unpleasant sound, just a different sound.

I've never really been around too many forged engines, or ever seen a forged 2ZZ - so wondering what it should sound like.

Don't really know how to answer this.
I've been in a forged 2zz @KRAMSNEHPETS has one with a rotrex but that is low compression.
Don't remember it sounding anything different to any 4 cylinder petrol at idle.
Are you thinking there is something wrong with your engine?
Surely this is hard to know until its been mapped.
Not sure we have any members who have gone high compression on a 2zz to ask.

[AJRFulton]

Just rebuilt my engine.

I'm running (at least) 12.6 compression ratio (12.3 Mahle pistons with +0.3 MWR flat faced valves) - the head has also been skimmed, so the compression ratio may well be in the region of 12.7-12.8.

Also running MWR springs and Piper Stage 3 cams on the head (although my 2ZZ's have always had springs and cams - so tuned to what they sound like) and Carillo H beam rods.

My question - what exactly should the engine sound like when compared to the standard 2ZZGE

The engine has not been mapped or run in properly yet.

My observations - Knock value on the Apexi has increased slightly - on a good OEM engine at idle this would be 5-10, and maybe be about 20-30 at revs. I'm seeing an idle of 10-15 and 30+ at revs.

The engine also makes a ticking sound. I can best describe it as a similar sound to what the 2.2 diesel engine in my transit makes at idle. It isn't an unpleasant sound, just a different sound.

I've never really been around too many forged engines, or ever seen a forged 2ZZ - so wondering what it should sound like.

Don't really know how to answer this.
I've been in a forged 2zz @KRAMSNEHPETS has one with a rotrex but that is low compression.
Don't remember it sounding anything different to any 4 cylinder petrol at idle.
Are you thinking there is something wrong with your engine?
Surely this is hard to know until its been mapped.
Not sure we have any members who have gone high compression on a 2zz to ask.

Just after reassurance that it is ok - there nothing in the pressure/compression numbers that makes me think anything is wrong with it - but it sounds quite different to how the OEM engine sounds.

A harsher note from the engine than OEM, although exhaust note sounds about the same (I'm talking about the physical sound of the moving bits in the engine). I had my nephew drive it up the road and back, and it sounded like it always sounded once the actual engine noise was out of earshot and you could only hear the exhaust note. Admittedly as it warms the sound improves - still harsher than OEM, but it smooths out a bit - I haven't had the car anywhere near race revs or temperatures yet.

I'm just slightly concerned by the knock values being up a little bit and this diesel-esque ticking sound.

[thetyrant]

Ive built a few forged engines all be it not of the Toyota variety and have all been turbo mitsubishi evo engines, however ive never found the engines make a hugely different sound once warmed up at least, when cold ive had some piston noise due to the larger bore clearances often used on forged turbo engines but once you get some heat in they quietened down.

The ticking sound would be a concern to me and could well be some contact internally especially if it sounds like its at the top end, did you check the piston/valve clearance was ok ? maybe drop the oil and filter for alloy particles and magnet for any steel/iron, or if you have a borescope get plugs in and have a peek inside, plugs might tell a tale as well.


Are you able to get a video of how it sounds ?

[thetyrant]

Found below thread and video on celica forum of someone with similar spec and issues, does your sound like that?  its very diesel sounding!

https://www.newcelica.org/threads/more-diesel-tractor-noise-on-2zz-celica.330982/

Video -

[AJRFulton]

All things were within spec when assembled - I cannot remember the piston clearance value as it's been a good 10wks since it was measured, but it was within the spec - valve clearances are about 0.15 on inlet and 0.2 on exhaust - all within spec, be that OEM spec or the spec specified in the part. I had the spark plugs out yesterday to do both a leak down and compression test - plugs still look new after maybe a total of 20-30 minutes running time - and compression/leakage values are solid - even on an engine that is has engine oil at 80^c - I'm not reving it yet to get the oil up and over 100^c and the engine fully warm.

The engine just sounds a bit "diesel" like on start up - it improves with heat - but definitely a more clackity sound than OEM. It's not a bad sound as such - just a different sound from OEM. On revs and load, the engine sounds on point. However at idle and off load it is definitely rougher.

I don't think the pistons are coming into contact with the valves. It's not that type of sound.

[AJRFulton]

Found below thread and video on celica forum of someone with similar spec and issues, does your sound like that?  its very diesel sounding!

https://www.newcelica.org/threads/more-diesel-tractor-noise-on-2zz-celica.330982/

Video -

Difficult to get a proper feel off the video - but I'd say that video is even more pronounced than what I have - however the sound is very similar, but mine is just not as diesel like - I am maybe 75% of what the video is showing.

[thetyrant]

Was it a new block i cant remember ?  reading that thread i linked above apparently his was 150k mile block and out of spec and supposedly causing the noise, very diesel like on that video!

[AJRFulton]

Was it a new block i cant remember ?  reading that thread i linked above apparently his was 150k mile block and out of spec and supposedly causing the noise, very diesel like on that video!

It is a new block, yes.

I cannot remember the piston clearance although 0.003 rings a bell.

Seeing that video reassures me a bit that my sound is normal.

[Carolyn]

Do you have a stethoscope? It would help you to pinpoint a rough area where it's coming from - top, middle, bottom, left, right.  Only a few quid on your favourite auction site.

Once you know that - then you at least know where to inspect.

It shouldn't be making that noise, I don't think, so it's worth tracking it down before you use it in anger.

A loose bearing cap?

[AJRFulton]

Found below thread and video on celica forum of someone with similar spec and issues, does your sound like that?  its very diesel sounding!

https://www.newcelica.org/threads/more-diesel-tractor-noise-on-2zz-celica.330982/

Video -

When I watch that back again - how it sounds about 40 seconds in - after they rev it a bit - is maybe more like how mine sounds at idle from cold start. It has that 'tick' noise - but my engine sounds smoother that the one does at the start of the video.

As my engine warms the slight tick remains but the engine continues to sound smoother and smoother as the heat gets into it - which is pretty much the same pattern I hear on the video, it's just more exaggerated than what I have.

That video and the comments have given me some confidence this is normal for the spec I'm running.

Even looking at the oil, with every moving bit and the block being new - I sort of fully expect to get some shimmery metal in the oil filter at the first oil change, perhaps even the odd larger flake in the sump. Unless it is excessive, it would be hard to draw any conclusions until the engine has did a couple of hundred miles.

[Frank Rabbets]

Sounds like tappets in the video. Anything serious would have gone bang by now especially piston hitting valve or loose bearing caps. Not too familiar with petrol injectors.

[thetyrant]

Just send it     i would get a heatcycle into it and after fully warming up run it through the revs to get the rings bedded, no pottering about use most of the rev range (no high loads from low revs though) and that should get rings bedded nicely then change oil and see how it looks.

You shouldnt get anything major in the oil if all is well

[Dev]

That dieseling sound on these engines often times comes from a variety of things. A lot of times it comes from not enough oil pressure in the VVT oil circuit causing a chattering of the lock pin on the VVT actuator or even just the pin itself. Its usually louder cold and then quiets down as the car is up to temp and usually most apparent at idle.  It could also be the chain tensioner or belt tensioner and many other causes that has to be investigated. 
 What I would do in your situation is get an oil analysis to see which wear metal is significantly elevated  and then you can figure out where it might be coming from however if it all checks out and its normal wear for an engine that is breaking in then I would have a little more confidence that its ok but I would perform another analysis down the road once the engine settles out.

[normanh]

My first thought is timing chain tensioner or a tappet. Like the old Ford CVH used to.

Norman

[Beachbum957]

Forged pistons typically "grow" more than cast as they warm up, so they often have slightly greater clearance when cold. Because of how they expand, they are also typically shaped slightly differently than cast. I built a number of race engines with forged pistons, and they all were a bit "rattlely" when cold until the engine is completely warmed up. 

As I learned from experience and from a piston manufacturer and other engine builders, proper warm up is very important with forged pistons, particularly when running high compression ratios.  The pistons should be near running temperature before they are highly loaded, or they could be damaged.

[jonbill]

what is the spec of the cams, lift and duration?

[AJRFulton]

what is the spec of the cams, lift and duration?

I have Piper Stage 3 Cams

You cannot view this attachment.

[AJRFulton]

Forged pistons typically "grow" more than cast as they warm up, so they often have slightly greater clearance when cold. Because of how they expand, they are also typically shaped slightly differently than cast. I built a number of race engines with forged pistons, and they all were a bit "rattlely" when cold until the engine is completely warmed up. 

As I learned from experience and from a piston manufacturer and other engine builders, proper warm up is very important with forged pistons, particularly when running high compression ratios.  The pistons should be near running temperature before they are highly loaded, or they could be damaged.

Car is only used on track, it is no longer road legal - mostly competing but used on the odd track or testing day.

The only time it gets used when not already up to idle temperature (about 80^c oil temp at idle - about 110-115^c when on track) is loading and unloading onto the trailer, and moving it about my yard and or the paddock.


It's booked into the tuners for next Friday, so a hard run in - then a quick inspection of the cylinders whilst doing the oil change - and map the car, and..... detune it.

For class purposes (based on power to weight) I only run about 180bhp even though this set up would be good to 195bhp. However, I'm after the mid range torque increases which take a good chunk off lap time. Running the Piper Cams + Fidanza Flywheel over stock was worth about 1.5 seconds around Knockhill, so hoping this set up shaves another 0.5 or so off the cars potential.

[shnazzle]

First stg3 cammed car I've seen here since 2013.
Interesting. Is the car usable on road?

Edit: and this is what happens when you ignore the "Someone posted in the meantime" notice...

[AJRFulton]

First stg3 cammed car I've seen here since 2013.
Interesting. Is the car usable on road?

Edit: and this is what happens when you ignore the "Someone posted in the meantime" notice...

The car was already very clumsy at low speed. Paddle clutch and Fidanza flywheel can be difficult driving around people in the paddock and I'd be lying if I said I haven't stalled on occasion - I don't imagine it will have improved with lighter internals and stage 3 cams.  However that set up is superior when driven hard which is what the car is for - if building for the road I personally wouldn't bother with the aluminium flywheel or paddle clutch - the gains aren't physically noticed unless you look at the lap timer, but the detriment to the driving pleasure is definitely noticed as it just makes the clutch clumsy at every day speeds.

It could be made road legal, but it wouldn't be pleasant to drive on the road. It's stiffness alone sees to that (can lift 3 wheels off the ground with the jack.). Plus I have perspex windows, no heater, uncomfy race seat, no sound deadening and the hard top takes about an hour to remove as it's incorporated into the roll cage (I keep it on for aero reasons - the cars slower without it)

[shnazzle]

First stg3 cammed car I've seen here since 2013.
Interesting. Is the car usable on road?

Edit: and this is what happens when you ignore the "Someone posted in the meantime" notice...

The car was already very clumsy at low speed. Paddle clutch and Fidanza flywheel can be difficult driving around people in the paddock and I'd be lying if I said I haven't stalled on occasion - I don't imagine it will have improved with lighter internals and stage 3 cams.  However that set up is superior when driven hard which is what the car is for - if building for the road I personally wouldn't bother with the aluminium flywheel or paddle clutch - the gains aren't physically noticed unless you look at the lap timer, but the detriment to the driving pleasure is definitely noticed as it just makes the clutch clumsy at every day speeds.

It could be made road legal, but it wouldn't be pleasant to drive on the road. It's stiffness alone sees to that (can lift 3 wheels off the ground with the jack.). Plus I have perspex windows, no heater, uncomfy race seat, no sound deadening and the hard top takes about an hour to remove as it's incorporated into the roll cage (I keep it on for aero reasons - the cars slower without it)

It's just a track car

I just missed that is all

[jonbill]

I think that much lift is going to be more noisy. I think that would account for the tappety noise.

[AJRFulton]

I think that much lift is going to be more noisy. I think that would account for the tappety noise.

I think that much lift is going to be more noisy. I think that would account for the tappety noise.

Watching that video yesterday filled me with more confidence.

The ticking noise isn't too excessive - but I will give the valve clearances another check once the car is ran in and tuned. By that time it will have a few hours on the engine, so everything should be properly seated and settled.

Valve clearances shouldn't change by much, if anything, as it is entirely mechanical - But it's an easy thing to check and verify.

[jonbill]

My (limited) experience is that higher lift is noisier than lower lift, for a given valve clearance.
It seems sort of intuitive - the lobe has to hit the valve harder to lift it further in a similar period of time.