it's been a while since i posted in here, but here it goes..
go to www.eng-tips.com. they have some very interesting forums on intake design concerning bmw's m3 engine. apparently the plenum size of the intake is 14-18 liters, and this was achieved by port throttle bodies. In theory you want the air in your plenum to be moving slowly for your "tuned" runners to operate as designed. if we try to create a large plenum using only one throttle body, we get aweful throttle response because the engine doesn't see the pressure drop for a while because the throttle body is too far from the cylinders. I guess this is how tunnel ram works on racing engines, they don't care much about low-end with 3500rpm stall converters. anyway, check out this link, because there's a lot of good info there but don't take everything as law. i have thought about doing this for our cars but it seems to be a waste of money. even if you could concieve some sort of port throttle system, the MAF wouldn't see increased flow for a second when you stomp on it.
eng-tips.com
go to www.eng-tips.com. they have some very interesting forums on intake design concerning bmw's m3 engine. apparently the plenum size of the intake is 14-18 liters, and this was achieved by port throttle bodies. In theory you want the air in your plenum to be moving slowly for your "tuned" runners to operate as designed. if we try to create a large plenum using only one throttle body, we get aweful throttle response because the engine doesn't see the pressure drop for a while because the throttle body is too far from the cylinders. I guess this is how tunnel ram works on racing engines, they don't care much about low-end with 3500rpm stall converters. anyway, check out this link, because there's a lot of good info there but don't take everything as law. i have thought about doing this for our cars but it seems to be a waste of money. even if you could concieve some sort of port throttle system, the MAF wouldn't see increased flow for a second when you stomp on it.
eng-tips.com