ACT Twin Plenum upgrade

[john57]

If anyone has done this upgrade to an otherwise standard engine what increases did people get in power and torque - after a remap - and how much better was it to drive ???

[trackcar]

Don't know about twin plenum upgrades etc, but I've yet to see a std car need remapping for underfuelling even with relatively high-breathing mods ..

for instance I've just taken a 5 litre griff from 262 to 284bhp and the A/F Ratio is still healthy, in fact the air flow meter seems perfectly capable of scaling up this kind of increase.

[stainless_steve]

I have this setup on my 450 SEAC,it is a bit of a wild spec engine from new,solid lifters,race cam ect.After the ACT twin plenum was fitted i noticed it had better throttle response,and more get up and go.