Performance Camshaft on Automatic

[chu346]

What's the wildest cam i could use on my 2.7 engine i'm building? I just feel abit scared to go too wild, and stuggle with a bad idle.

[MONSPORT42]

I have a 2.7 Sport auto - (see spec in members rides). I have toyed with the idea of a performance cam myself but like you have been put off by the possible lumpy idle. The thought having to put it into neutral every time I stop to avoid 'kangaroo creep' kept me standard. I have been told that I would probably get away with a shrick 272/272 but that hardly seems worth the effort and the cost. Might do it if I need to replace the cam anyway. The reason for not wanting one is that it will only really improve top end performance and that at the expense of low rev performance which is where the high torque 2.7 really shows its power in an automatic. There was great link to the puma racing which explained the relationship between torque and bhp which i'll edit in when I can find it. It basically says that these type of high torque engines work better with the standard cam.
Here's the link
http://www.pumaracing.co.uk/power2.htm

[chu346]

If you ain't changed the cam, how much power are you getting? and what kind of engine management do you have?

I take it you had the head gas flowed at bexleys. If so do you know how much they charge?

[MONSPORT42]

Bexleys organised the gas flowing/porting although they didn't do it themselves and from memory it was about Ԛ£450. I changed to a MAF system with piggy back Unichip. (MBE wouldn't talk to the auto gearbox) I did this as the torque converter and mechanical AFM combined made for a delay in the power delivery. Still stuck with the torque converter though but throttle response is much, much better. This set up has been on Bexley's rolling road for a good many hours of mapping and is currently showing about 237bhp/219ft lbs torque (flywheel figs) although there is always a lot of debate about autos on R/Rs.

[chu346]

Well i really wanna go for the 272cam, but i could just get the head ported for the same money and be sure of having a good idle.
Its one of those things where you don't know if you should follow your heart or your brain.

[chu346]

Oh BTW Monsport do you know what pistons your using? I assume your using the ones from the 323i as well as the head.