9.4:1 or 10:1 pistons?

[Ivan141]

I've no idea about the 20mm items. I doubt I have a 42/20 crank in any block I own (still have a 7-rib bluetop to pull apart, but to be honest I've never heard about or seen a 20mm non-smallport piston), so I never ordered 10.3:1 pistons.
You got the pound and dollar signs the wrong way round by the way.
I paid 100€ for the 4 16030 pistons (toyota original), but the price ended up being 210€ with postage and taxes. This is something that most european guys need to keep in mind when ordering 'cheap'.

As far as NPR quality is concerned: I'm sure there are quite a few engines running these by now. I've read somewhere that NPR was an OEM supplier, and if I had to judge by looks, I would believe it immediately. They are exact up to the markings cast into the pistons.. only difference between the NPR's and original is the lack of 'toyota' down the sides (the 16020 is there on both OEM and NPR pistons in the same font).
Just judging by appearances I dont see any reason to distrust the NPR pistons. They have the same weak-point as OEM: the oil slot beneath the oil rings. There is a minute difference in machining at the ends.. the OEM 16030's have a wider end-hole on that slot, the NPR's dont, which is probably better. This is a weak point because the ringlands always break somewhere along that slot (when they break.. took my 1st bluetop 300.000 km's).

Piston weight can be back-calculated from the values I put up earlier and OST's 89g number: about 327g for the 10:1, and 304g for the 9.4:1 items.
Gudgeon pin Toyota = 89g, NPR = 68g

[Ivan141]

as promised, some side by side pics.
Excuse the quality, light conditions in the evening arent great.

16020 9.4:1 on the left.
16030 10.1:1 on the right.

[Alex170984]

Ivan141 Wrote:I've no idea about the 20mm items. I doubt I have a 42/20 crank in any block I own (still have a 7-rib bluetop to pull apart, but to be honest I've never heard about or seen a 20mm non-smallport piston), so I never ordered 10.3:1 pistons.
You got the pound and dollar signs the wrong way round by the way.
I paid 100€ for the 4 16030 pistons (toyota original), but the price ended up being 210€ with postage and taxes. This is something that most european guys need to keep in mind when ordering 'cheap'.

As far as NPR quality is concerned: I'm sure there are quite a few engines running these by now. I've read somewhere that NPR was an OEM supplier, and if I had to judge by looks, I would believe it immediately. They are exact up to the markings cast into the pistons.. only difference between the NPR's and original is the lack of 'toyota' down the sides (the 16020 is there on both OEM and NPR pistons in the same font).
Just judging by appearances I dont see any reason to distrust the NPR pistons. They have the same weak-point as OEM: the oil slot beneath the oil rings. There is a minute difference in machining at the ends.. the OEM 16030's have a wider end-hole on that slot, the NPR's dont, which is probably better. This is a weak point because the ringlands always break somewhere along that slot (when they break.. took my 1st bluetop 300.000 km's).

Piston weight can be back-calculated from the values I put up earlier and OST's 89g number: about 327g for the 10:1, and 304g for the 9.4:1 items.
Gudgeon pin Toyota = 89g, NPR = 68g

Oh yes so I did haha

I'm actually glad you said that about the pistons, as I was unsure of the quality and was concerned that everyone else buys branded pistons like arias and wiseco etc but feel better about that now.

Toyota in the UK wanted £62 per piston in 0.5 oversize!!!! God I'm glad I got a bargain now!!

[pack]

Are those low compression pistons the forged ones on the GZE engines?!

[Ivan141]

No