Hello Everybody,
I'm building a B18 motor and I'm looking for some tips and advise what to do to make the engine better What do I need to do ??
The specs for now :
- B18C4 block
- B16B 81.50 pistons
- B18C6 head
- Crower Stage 2 N/A cams
- B16B Intake
- 4-2-1 2.25" exhaust

I still want to get the crank balanced and thinking about oversize valves but don't know if it will bring something

 

Search and read the FAQ section in here. If this your first build I would advise you use some pr3 or p30 pistons

 

Stay away from the CTR's they will put you in the high 12's for C/R and the PTV clearance will be too close for comfort imo. PR3's or jdm ITR's make for a nice high 11's C/R and great DD.

 

The engine was running on PR3's pistons and on the the C/R was over 12, now with the CTR's he C/R will be only 12.8:1..... A lot of engines in Poland are rebuild on PTC pistons and they are DD

 

12:1 compression is more than enough to extract a good amount of power out of an engine tuned on 93 octane or lower. There is no advantage to using PCT pistons in a gsr motor. At all. Clearances are that of your girl friend's pubic hair.

It makes more sense to put PR3's back in and work with the motor while tuning it, than work against it just so you can say "oh it has ctr pistons." PR3's and S2S2's, buy a quality header and exhaust, tune. Leave PCT's for B16's.

 

If the engine had over 12:1 with PR3 pistons it WILL be over 14:1 with CTR pistons unless you use a stupidly thick headgasket to drop the compression back down. Even then you'll still have that large piston dome hitting the head and blocking airflow and flame travel because its dividing the chamber in half at TDC.

 

you can use a pct but use a a b18b conecting rod so you can clearance de valve a do some good comprecion.... about 12.4@1 or 12.5 @ 1

 

I am currently running PCT pistons in a B18C block with a B18B crank and rods. I had to go with a .049" head gasket to prevent clearance issues. Needless to say my CR is right at 13:1 and I have to run 97 octane or higher to prevent detonation. I have a good tune and the engine runs great. If high octane fuel isn't a problem for you then go for it but in most cases it's a hassle to find high octane anymore and also expensive if you do especially for a daily.