TheDarkSideOfWill wrote:
For now I have the stock high performance 266I/244E cams.
I have an upgrade path planned to install extra 266 intake cams in the exhaust locations.
I also have a set of 288 regrinds and a pair of redrilled intake sprockets to advance intake cams 10 degrees on the shelf to play with after the 266E upgrade.
Those are durations at 0.1mm lift, IIRC. Yeah, I remember yours are in the range of 235 degrees at 0.050" lift.
With factory cams MAF is no issue, they sorted it for you so carry on.
Yes, I have more duration, @.006" at the valve I have 274/285....0,1mm is like ,004 so maybe 279/290 at the valve? and maybe another 5-10 degrees at the lobe as lash is about .010". For comparison my .050 numbers are 242/247 lobe, 240/245 valve....which are still relatively mild numbers. The ramps are steep to get the lowest seat to seat I could with decent .050 numbers to try to keep a decent low-end and port flows are high so more .050 duration doesn't add much until the engine is over 10k.....seat to seat number are mostly telling about idle and and low end, .050 is a good way to compare how different grinds impact top end.
Why are you talking about bigger exhaust cams? I was unable to get my exhaust flow as high as I wanted it and had to compensate with a bigger cam. If the factory used a much smaller exhaust cam that usually indicated the opposite problem but I know little of northstar engines....I did read the aroura indy engines needed 20 degress less exhaust than intake to work right but no idea if that in anyway applies.