My visit to Rennsport LAX!!!
- Thread starter The Mixmaster
- Start date
Azrielsc said:Man, tat is ONE sick workshop!! Imagine parading all the chio-est bimmers in town!
Btw, Wil, there isn't anything on TC at Samir's place? Cuz Kromex over at e46fanatics is running 500bhp with his TC setup!
Nope, there's no TC cars at Rennsport, only SCed cars..........
I know kromex is running TC, but dunno how reliable......
For ASA SC running at stock boost, car wun 'piang' even w/o ECU tuning!!
'The Great White'
Racebred said:
SCs in general have high int. port to exh. port pressure ratios, so will overscavenge if there is the usual race-NA overlap. For that reason race NA cams do not match SC setups at all.
Some extreme race applications where fuel consumption does not really matter, appreciate overscavenging though because the fresh AF getting pulled across cools the super hot exh. valves which are a main area from which combustion pressure leaks when warped or melted as well as of auto-ignition origin.
Race-spec turbo engines will have much lower int. port to exh. port pressure ratios - some approach race NA levels of near 1:1 so in those cases the cam profiles are quite the same as race NA ones. But for the most part, most street turbos [even the pretty high performance ones] have the reverse pressure ratio of SC. so instead these TC engine may go into intake reversion on overlap.
The 272 spec tells too little. One would need to know whether it is intake or exhaust, what the opposing side cam spec is, and how many degrees BBDC/ATDC/ABDC/BTDC they open/close, [which together will give overlap], full cam profile detailing lift at a range of points [not just peak] esp important if they are asymmetrical. Then of course there is the port flow rates which we will never know if it is a custom job. It all goes together.
On TC engine you can go aggressive on overlap if the int. to exh. port pressures get close to the NA levels. That would mean a really huge turbo [very low restriction exhaust side housing]. The other condition is if you have really uneven flowing valves and ports[like if the exh valves and ports seriously outflowed the intake ones]
Outside of overlap however, duration is always good, lift too - but lift will be limited by valvetrain mass. There is also no point in going big on lift if the port cannot take advantage of it and increase flow as lift does, or if the returns in airflow diminish so fast whilst the stress on the valvetrain goes sky high cos of the revs.
On TC engine you can go aggressive on overlap if the int. to exh. port pressures get close to the NA levels. That would mean a really huge turbo [very low restriction exhaust side housing]. The other condition is if you have really uneven flowing valves and ports[like if the exh valves and ports seriously outflowed the intake ones]
Outside of overlap however, duration is always good, lift too - but lift will be limited by valvetrain mass. There is also no point in going big on lift if the port cannot take advantage of it and increase flow as lift does, or if the returns in airflow diminish so fast whilst the stress on the valvetrain goes sky high cos of the revs.
Remus325
Well-Known Member
Bernard at BVO is already thinking of bringing the ASA SC. He just came back from a convention in Taiwan where some german tuners are already doing the ASA SC. He told me that the whole kit plus setup will cost est SGD 15K. Dunno if he is also trying to get LTA approval but i highly doubt it.
