View Full Version : ST185 engine rebuild

11-29-2015, 07:05 AM
Hello everyone.

First of all please excuse mybad English.

I am working on my ST185 i brocke the engine 2 years an half ago and the car was sitting in the garege sinse then.
Finaly I take out the engine from the car and put it apart, i found out that one of the pistons is damaged, notheng else is damaged, i try to find OE pistons but unfortunatly i understand the 13101-88381-02 is out of production and i can't order this anymore.
Now i am wondering is it possible to put rev3 pistons 13101-88480, because i want to make the car in the original looks and mods.
Only thing that i will change is the head gasket type, i will update it to steel version from rev 3 engine.
It will be very helpfull for me if some one can tell me is it possible to put rev3 pistons in to my rev 2 engine.

11-30-2015, 09:02 PM
That's a good question. We need Vip09 to get up in here.

11-30-2015, 09:42 PM
There was a thread on the mr2 board a while back that outlined gen2/gen3 differences (I used it when I was looking for my gen4 parts that were compatible with gen3 and then cross reference back to the gen2 stuff). Gen2 pistons will work in a gen3 motor and vice versa (gen3 in gen2). Just get the pistons & rings to match (ie. 205 pistons, 205 rings, etc).

12-01-2015, 12:42 PM
I took a piston gen3 from a friend, so i can compare gen 2 and gen 3 pistons but i am more then sure that i will change the compresion ration on the engine , cuz gen 3 have 8.5:1 and gen 2 - 8.8.1, i am not sure if the metal gasket is thiner or not.
Good point of making the compresion ratio lower is that i can put a bit more boost around 16 - 18 psi with just fuel regulator, wideband O2 sensor and electronic boost controler. I have fuel cut defender and some shit from apex'i for the fuel, the fuel cur deffender and this electronic apex'i shit was instaled from the privious owner of the car and never had a chance to find our what this apex'i do and it do it. Probably i will take it out of the car cuz i am sure that because of this device i blow the piston (lean air-fuel mixture).
So let go back to rebuilding the engine fist then i can think about other shits and how to put some horse power without making huge changes.
I need an advice what to do with those pistons, i have an oprion to order piston that is same as brocken one, but it is used, and the other option is to put gen 3 pistons.

12-02-2015, 06:14 PM
Unfortunatly the piston has serius differences from the original one.
There are some after market set NRP in the web if some one has used those, please let me know what is the quality of those.

12-02-2015, 06:37 PM
the pistons the i have found for sale are Teikin & NPR, so the question is: are they good?

03-15-2016, 07:57 PM
rings are interchangeable. I rebuilt a 3rd gen engine using gen 2 rings stack OEM.

01-10-2018, 09:49 PM
I used NPR or NTR piston and rings. I bore out to 86.5mm from 86mm stock. It should be no problem as my car now have 2000+km on it
and the car runs reall good with no issue. Cometic head gasket and ARP head studs set.
On a side note, I prefer higher compression than the current 8.8 or 9.0 compression.
I am thinking around 10.0 compression.

Reason is my other car is a K24 boosted at 11.0 compression(cast piston) with meth injection for the past 8 years with no issue.(cheap 87 octane gas for Daily driver).