AdamB Posted August 11, 2013 Share Posted August 11, 2013 Yeah that's it mate, cam manufacturers decided to specify the duration @ 0.05" lift, however this isn't the peak duration of the cam, its just a helping hand in dialing the cams in. I see so many people choosing such wild cams like 280 degree's duration which just make them real lumpy and no bottom end power, when they could just opt to use a cam with a different LSA. Running a wide LSA gives a decrease in overlap making the cam much smoother and improved low-mid range, but limits top end power no matter how much duration of lift you have. Go the opposite way with a tight LSA the overlap increases meaning you loose bottom end torque, gives lumpy running but provides much better top end. The stock inlet cam has an LSA of 110 degree's, exhaust is 112 degree's. Ivan Tighe billet cam's have an LSA of 114 degree's, as you can see here the LSA is widened for aftermarket billet cams to provide smooth running with increased duration. Quote Link to post Share on other sites
enzo_e492901 Posted August 28, 2013 Share Posted August 28, 2013 (edited) I have recently acquired some 5E-FHE camshafts and over the bank holiday I took out my measuring tools. The camshafts were first measured using a dial caliper and then to verify the lift was measured directly using a dial indicator with the camshafts sitting in vee blocks. UKDM 4E-FE----------------------------------------------Intake:Base Circle + Lobe Lift = 40.85mmBase Circle = 34.05mmLobe Lift = 6.80mm (Base Circle & Lobe Lift - Base Circle) Exhaust:Base Circle + Lobe Lift = 41.05mmBase Circle = 33.90mmLobe Lift = 7.15mm (Base Circle & Lobe Lift - Base Circle) JDM 5E-FHE----------------------------------------------IntakeBase Circle + Lobe Lift = 41.60mmBase Circle = 34.05mmLobe Lift = 7.55mm (Base Circle & Lobe Lift - Base Circle) Exhaust:Base Circle + Lobe Lift = 41.35mmBase Circle = 33.90mmLobe Lift = 7.45mm (Base Circle & Lobe Lift - Base Circle) So 5E-FHE camshafts have+ 0.75mm lift on the intake+ 0.30mm lift on the exhaust They are the only two sets of camshaft I have access to at the minute. I will measure the duration of them one day too. Gavin Edited September 12, 2013 by enzo_e492901 Quote Link to post Share on other sites
Sudden Posted September 12, 2013 Share Posted September 12, 2013 the 4E-F carb cams differ to the other 2 sets. they have less duration and or Lift as I recall. low end torque, workhorse engine ? I have a set. Wish I weren't so far out to sea, I'd donate them to be properly measured and updated in the database. had seen the specs on another forum before I had acquired the 4E-F though. Quote Link to post Share on other sites
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