DaveInVA
CEG'er
I was wondering if anyone knows of manufacturers of "spicier" aftermarket cams for the CSVT ? Around 2002, it was said that none were available, but I thought perhaps at this point, there might be some . . . ?
Piper cams seem to offer a cam for Duratec V6.
http://google.motorsportworld.co.uk/framefix-detrange2.asp?MANUFACTURERS=1243
It is for Essex V6 3.0. But it seem to work on Duratec, too.
The ST220 is the same as older Escape V6 3.0 w/o VVT.
Intake Open = 4 deg. BTDC
Intake Close = 48 deg. ABDC
Intake Duration = 232 deg
Exhaust Open = 56 deg. BBDC
Exhaust Close = 12 deg. ATDC
Exhaust Duration = 248 deg.
Max Lift = 9.3mm
It is discussed by FCO and Talkford.com and my friend had visually compared both of them.
The link is at:
http://www.fordcontour.org/topic/13063-st220-parts-myths-topic/
and
http://www.talkford.com/topic/129866-st220-cams-specs/
The 20-ish extra hp is from ST220's intake and exhaust designs.
Hmm, then this should be quite interesting. I'll ask my friend to measure the cams he removed from his ST220.
He installed SVT cams on his ST220 few months ago, he does feel the difference, and quite a lot.
Measuring one should be the closest to the facts.
Ran out to the shop and checked a set of donor Escape cams and ST 220 cams. These are the specs for the donors.
Escape
Intake-total crank dur 232deg @.000in lobe lift. Max valve lift - 8.727mm
Exh-total dur 248deg @.000in lobe lift. Max valve lift - 9.53mm
ST 220
Intake- Crank dur 238deg @.001in lobe lift. Crank dur 149deg @.050in lobe lift. Max valve lift .370in, 9.40mm.
Exh- Crank dur 274deg @.001in lobe lift. Crank dur 177deg @.050in lobe lift. Max valve lift .379in, 9.63mm.
Note the cam timing is not the same for these two donors.
I know nothing of the Mazda cam specs.
There must be an error in your measurement. Those durations are for very radical cams or they are not for .050" lobe lift. The following were measured by cam doctor machine at Crower cams for M400 cams.
duration at .005 lift duration at .050 lift Lobe lift
Intake 220 158 .187
Exhaust 250 185 .189
I use rocker ratio of 1.8 for valve lift calculations but I am not 100% sure about the accuracy of this number. Mazda 6 specs were meaured and they were the same as above. Lift and durations for a universal 3.0 Duratec cams were also measured and both are slightly less than above.
I forgot to mention that cam changes require computer recalibration which is very easy in my case since I use Electromotive computer. Stock computer and wirings were tossed.
Hmm...This is interesting.
The thread you pointed also has this posted, measured at Crower. They are a bit different, again.![]()
Any idea where the threshold limit on lift is that results in coil bind on 3.0L OEM springs, i.e., 2005 Escape motor?