Act triple plenum on a stock 450

[Overhere]

I'm still considering options on increasing throttle response and maybe adding some power w/o opening the engine and changing/improving heads or cam. Anyone have an opinion about the Act triple or twin plenum?

I heard a standard 72mm plenum with a spacer would be more cost efective option and gives good results.

Anyone done any of these and had good/not so good results?

In any case do I need to remap the ECU if I do any of the above changes?

Thanks

[lwt]

Not exactly the same as I had a couple of mods to cam and ECU first (so no restrictive Air Flow Meter in the piping), but just changing from a 65mm to a 73mm plenum gained 15hp (not bad for £195!) and if you talk nicely to Joo at TrackCar Solutions he has an alternative inlet bend that was worth another 14hp. My guess is that if you go for the ACT mod then at the very least you should look at a larger Bosch AFM and you would need a remap to make the most of it all. For the cost of a new AFM, a mappable chip and the remap itself you might want to consider ditching the Lucas ECU and the 1940's distributor and getting a new ECU (KMS/Emerald/Omex). My own experience (with the KMS) is that it not only releases more power but improves throttle response and driveability too.

Ian.