advice for poncam purcahse please!

[Black BNR32]

^
Hey Jon, Any data/results to share to back up your claims? I'm interested!

[cortexx]

I'd like to see a bit more data on this too , im up for cams to increase exhaust pressure to spool the turbos faster . I dont want a horrible lumpy idle and a narrow high rpm power band .

[Dragon Humper]

Sorry guys, I don't have anything handy right now. It took me about 2 years to find info on the J-land offerings in regards to actual lift and duration #'s on their cams but don't know where it is (someone in AU actually took the time to degree a PON and PRO offering), they don't seem to want to be too chatty on them for a good reason.

If you look at the duration #'s of the Kelford offerings at 1mm lift (which is pretty close to the NA method of giving you duration at .050") you will see that the actual duration at any meaningfull amount of lift to get the flow party started is around the 234 deg mark, give or take (on their 270 deg. advertized offering). The duration #'s on a 260 PON cam at 1mm are only 214 to 216, give or take (this info I remember from about 4 years ago). This tells you that the lobe ramp on the Kelfords are much more agressive which pops that valve off the seat much faster to squeeze flow #'s out of a cam with only 9mm lift that would take an old J-spec cam 11mm to do. This is especially true for untouched heads as you will get your best flow in the 6mm to 10mm lift area, so going higher than that on stock ports is pointless.

I have seen at least 100 cam tests for both FI and carb in either NA or boosted over the years and time and time again you will see a big jump in mid-range with no loss in bottom end (unless you are going really big) and the boosted #'s were always stellar right to redline with a cam that has medium lift and larger duration than you think you can have combined with a 112 to 114 lobe separation (which you can adjust with cam gears). You will have a bit of a choppy idle, but with FI will drive just like stock (with the right tuner) and sound bad-ass with a 3500 to 8000rpm window of awesomeness.


Jon.