BRZ-123 174 Report post Posted June 10, 2021 I have been looking at some stats and every car I compare to / with, our cars torque figures are quite low when turbo/ supercharged. Let's take examples : 1. GR Yaris with a 1.5L turbo it makes 380 NM torque2. Golf GTi with a 2.0L turbo makes 370 NM3. Civic Type R with a 2.0L turbo makes 400 NM. All of them Road legal and catted. Ours on the other hand , makes only around 300 NM with FI(both turbo and SC). Why is the potential torque low technically compared to other engines? Sent from my SM-G781B using Tapatalk Share this post Link to post Share on other sites
Varelco 211 Report post Posted June 10, 2021 Because the conrods lack strength to take any more torque. The high compression ratio restricts the amount of boost pressure you can run. You aren't comparing apples to apples. If you take the factory designed turbocharged FA20 then the figures are more comparable. the JDM FA20DIT is rated to 400NM. 1 BRZ-123 reacted to this Share this post Link to post Share on other sites
will300 812 Report post Posted June 10, 2021 Don't forget our cars have quite a high compression ratio, which is favourable to N/A applications not boosted applications. Using you're above list, all the car listed have a lower ratio. 1. GR Yaris - 10.5:1 2. Golf GTi - 9.6.1 3. Civic Type R - 9.8:1 And as @Varelco states the conrods weren't specifically designed with boosted power in mind so they were made to support a lower torque limit. 1 BRZ-123 reacted to this Share this post Link to post Share on other sites
BRZ-123 174 Report post Posted June 10, 2021 Because the conrods lack strength to take any more torque. The high compression ratio restricts the amount of boost pressure you can run. You aren't comparing apples to apples. If you take the factory designed turbocharged FA20 then the figures are more comparable. the JDM FA20DIT is rated to 400NM.It's interesting what you say and fair point the factory FA20F engine having higher torque. The compression ratio of that engine is 10.6:1. Conrods are no different to the FA20D AFAIK. So I think high compression FI means lower torque (not necessarily lower power) as power figures are in the same ballpark as other 2.0 boosted engines. Sent from my SM-G781B using Tapatalk Share this post Link to post Share on other sites
Church 209 Report post Posted June 10, 2021 One of FA20 claimed "traits" vs old EJ engines was increased efficiency .. partially gained by shaving any excess material wherever possible .. obviously that adds limitations when you want to boost to higher levels. Otherwise i'd say that FA20 is producing power & torque remarkably well for current stricter and stricter emission requirements. There is reason why most vendors (supercar makers excluded) giving up making high specific output NA engines, including traditionally among best NA 4-cyl engine makers, Honda. Latest gen civic type-r engine in my eyes marked end of NA era most. "If even they gave up".. 1 BRZ-123 reacted to this Share this post Link to post Share on other sites
BRZ-123 174 Report post Posted June 10, 2021 Don't forget our cars have quite a high compression ratio, which is favourable to N/A applications not boosted applications. Using you're above list, all the car listed have a lower ratio. 1. GR Yaris - 10.5:1 2. Golf GTi - 9.6.1 3. Civic Type R - 9.8:1 And as [mention=1137]Varelco[/mention] states the conrods weren't specifically designed with boosted power in mind so they were made to support a lower torque limit.Thanks Will. All the magic seems to be in compression ratios. I I state above, I do not see a different con rod used in the FA20F which is the WRX config.. Still not happy with the torque though. needs to be 400 NM. Nice video to see the differencesSent from my SM-G781B using Tapatalk Share this post Link to post Share on other sites