Originally Posted by Jordo!

Answers to this question are not going to give a clear picture unless the responses are isolated to one type of dynamometer using one specific correction factor (preferably SAE as STD tends to overcompensate on NA cars) and the vehicles are all dynoed in the same gear.

For example, some MT's dyno in 4th and others in 5th -- that affects the final numbers, at least on a dynojet. the AT will almost always be dynoed in 4th.

Also, many people like to report STD numbers, because they tend to be higher.

Finally, peak numbers can be misleading -- the Z has a tendency to show a spike in power as you approach fuel cut.

Even then, with everything done exactly the same way, expect some variance...

Numbers will be all over the place on load bearing dynos -- some Mustang dynamometers break hearts, others dont.

As far as peak power goes, Z's with some sort of intake, CBE, TP/HFC's, and tune will generally see between 300 and 310 on a dynojet. A bit more with LTH and pulleys. No clear difference between AT and MT.