Finally managed to measure it 😀
It was bit more what BGB said… (2.9Ω)
Tag: 4a-gze
The piston debacle
Sheesh! Finding proper 4A-G(Z)E pistons is a mess!
The following pistons are listed with 20mm pin and 30.68mm (1.208″) compression height
- Wiseco K506M815
- CP/Carrillo SC7653
- Wössner 9035D050
- Wössner 9191D050 is strange. It has a 30.6mm compression height. WTF?
- Wössner 9278D050
…and following pistons have 20mm pin and 30.5mm (1.200″) compression height
- Supertech P4-T4AG16-20-8
1.5-CR11 - Toda 13010-4AG-001
- Toda 13020-4AG-001
- Toda 13040-4AG-001
- Arias AP331669
- Arias 3721070
- Arias 3731220
If my current pistons can be shaved a bit, I’ll keep them. I’d love to get the compression height from 30.68mm to 30.5mm and shave a bit off the piston crown to get dome volume somewhere around 2-3cc. This would drop the compression rate little bit below 11:1.
Otherwise I’ll get the Supertech pistons. They’re pretty damn near perfect. 🙂
Difference in compression height numbers probably comes from two pin sizes. Early 4A-GE engines had 18mm pin, later models had 20mm. Some of the companies dont seem to care about this.
I promised myself that I wouldnt get any parts from a country, which still uses imperial units. Meh…
- Supertech = imperial
- Toda = metric
- Arias = imperial
- Wiseco = imperial
- CP = imperial
- Wössner = metric
Wössner would do, they’re from Germany, but why do they have that compression height error too?
Matrix Garage has some pistons too, based on their own design.
Aluminium oxide inside oil passages
That white, powdery stuff there is aluminium oxide. And it’s baaaaad.
While being washed for those technical coatings, something happened and insides of the cylinderheads got exposed to washing agent. Aluminium reacted with washing agent and end result was aluminium oxide.
Aluminium oxide is that same stuff that is glued to paper to make sandpaper. Wonder what it would do inside my engine if left there…?
Nah, I’m taking it back to the coating company 🙂
Connecting rod info
Better put this info up for later
ATM I can’t recall where I found the numbers, but with these I made my order to Auto Verdi and everything fits.
So, the stock 4A-GZE conrod measures:
Wrist pin diameter: 20mm Pin end width: 21.825mm Center to center length: 122mm Big end diameter: 45mm Big end width: 21.825mm
Parts from coating
Got some parts back from coating!
Cylinder head has some white crud all over it. No idea what it is and how to get it off.
Valves and everything (I mean everything, even the plugs) were coated in heat resistant stuff. Outside, cylinder head got a coat of stuff that helps heat to radiate away from it.
This is a Ferrari F360 flywheel if I remember correctly. Widric found it from our stash. 🙂
Pistons got three different coatings on them. Top of the piston was coated with heat resistant, skirts with friction stuff and the underside with that same stuff as cylinder head that will radiate heat away.
Some bits are now sandblasted and powdercoated. I will have to find some nice paint(s) to do the letters.
Not pictured here are the new camshafts, all the bearings and the block. Camshafts and bearings got a coat of that friction reducing stuff, while the cylinders were rubber with tungsten powder to… well.. reduce friction 🙂
I will get my exhaust manifold and turbo coated as well.
Crank and conrod clearances
Crank tolerances were within 0.035-0.050mm, conrod pins were 0.035mm according to plastigauge.
For sheer fun I measured conrod pins with my micrometer and all four were bit more than 41.99mm (very near to 41.995)
Decided to go with ACL std sized bearings.
New Supertech valves
A box full of valves has arrived!
Intake + exhaust valves in separate boxes
New vs. old
Toyota 4A-GZE 365cc injectors
As much information as possible about toyota 4A-GZE 365cc injectors. This post will get some updates later.
- Low impedance, found a web page claiming 3.4Ω, another one claiming 2.9Ω. Better measure mine.
- NipponDenso built
- Connector is surprisingly NipponDenso (Sumitomo) low guide connector.
- They’re red 🙂
- 365cc – 3bar, but I dont have the normal 4A-GZE AW11 fuel system pressure available. I’m guessing the pressure might be around 2.5bar and actual maximum somewhere near 300cc, maybe even less.
Nozzle. This type might do twin stream to both intake channels.
Bottom seal diameter is around 16mm. I forgot to measure the height.
Toyota calls this part insulator, injector vibration. Part number 23291-41010
Part number is 23250-16061. There are some differences between injectors, mine seem to be marked white so the complete part number for my injectors is 23250-16061-04.
Older 4A-GZEs had 23250-16060 injectors. I’m unsure how they differ from these.
From bottom seal center to upper seal center (c-to-c) is around 62mm
Side view
Total length is 72,5mm
Connector. Dirty AF.
The rubber thing next to connector and “below” top o ring should be Grommet (For fuel injector) – part number 90480-13005.
The widest point is 21mm
Nozzle diameter is 10,4mm
Another nozzle picture
Top o-ring diameter is 11,5mm. Toyota calls this one Ring, O (For fuel injector) – part number is 90301-07001.
Thickness is 2mm
The other wide bit at the bottom of the injector, 16mm.
Auto Verdi conrods
Nothing really spectacular here, they’re awesome. Pistons fit too 🙂
Piston rings + crank girdle
Checking pistons and rings:
Gap on fourth cylinder is 0.35mm.
Pistons seem to fit into block. That is a good thing.
A package from Manon Racing Products arrived, containing Toda timing belt and oil pump gears, N2 style additional timing belt tensioner (or guide) and a crank girdle.
Timing belt tensioner. Fitment is very good.
And the crank girdle. A serious piece of hardware. I needed only some stiffening but now the engine will be bombproof.
Veeery nice 🙂
