Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB - View Single Post

elitegunslinger · 03-13-2019, 02:32 PM

This chart I made utilizing information I've found from previous safe boost levels on the stock motor of 12.5:1 it seems like these engines are good for a final compression of about 22 or less on 91/93 octane (green) and FCR of 35 or less for E85 (orange). I haven't been looking into E85 as it's not readily available in my area.

Compression Vertical and PSI Horizontal

Are there additional factors or limitations of the FA20 platform I should be taking into account before proceeding with building a boosted motor? Any reason there aren't more 13.5 CR boosted FA20 in the wild?

Note:
These are extremely loose numbers and proceed with caution and the guidance of your engine builder / tuner.

03-13-2019, 02:32 PM	#1
elitegunslinger Senior Member Join Date: Oct 2016 Drives: 2014 BRZ Limited Location: NJ Posts: 120 Thanks: 10 Thanked 24 Times in 22 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	Safe Boost Compression Options This chart I made utilizing information I've found from previous safe boost levels on the stock motor of 12.5:1 it seems like these engines are good for a final compression of about 22 or less on 91/93 octane (green) and FCR of 35 or less for E85 (orange). I haven't been looking into E85 as it's not readily available in my area. Compression Vertical and PSI Horizontal Are there additional factors or limitations of the FA20 platform I should be taking into account before proceeding with building a boosted motor? Any reason there aren't more 13.5 CR boosted FA20 in the wild? Note: These are extremely loose numbers and proceed with caution and the guidance of your engine builder / tuner. Last edited by elitegunslinger; 03-14-2019 at 02:42 PM.