Aussieveedubbers

CT056 cam choice.

fullnoise3 · 2009-04-15T23:06:39+00:00

Welcome to the inside of my head. I've always wanted to start a post with that sentance considering how I rabbit on. Ye olde 1916 has gone from 76 to 99.9 HP over the years with no change in compression, exhaust or carbs. Cam history. Pobjoy old-steroids 37/68. Liked it, it's still mint with matching lifters. I may reuse it in another engine. It had good power, good fuel economy and didn't have enough lift to cause valve train wear (except with the 44 inlet valve street eliminators I chose when I had NFI). Webcam 109. This is a bit of an open wound. Some commercially dishonest yanks said to use this cam with 1.25 rockers and DRD Level 5 heads. To be safe I used it with 1.1 rockers and a smidge of coil bind ate the lifters after 1000 kms during the first track day. This was supposed to be equivalent to the engle 125 but more modern. Engle 130 No complaints in power and reliability. However it's a bit heavy on fuel. My freeway engine speeds vary between 3500 and 4000 rpm. It's richest at 2500 rpm. I think it's due to the overlap, reversion of such a long duration cam. What to try? For starters I'm going to try a rocker cam with chromoly pushrods even though there's nothing wrong with the 1.1 rocker cams. You should see my 130 and the lifters. There polished like chrome with not even a hint of pitting after about 8,000 miles, 5 track days, a Dutton rally, 2 trips to Portland and 2 trips to Warwick. A K8 is looking likely. The flow chart suggests the heads could do with the extra lift of 1.4 rockers. I want to reduce the duration to bring the power down the rev range a little and make the car a bit more economical on long trips. That way the cam change will pay for itself. A K10 is tempting after seeing how hard Colin's car goes. His heads are heaps bigger than mine though. Rembember I'm dealing with 040 heads with mini D inlet ports and exhaust ports that look stock except for the fact they've removed the exhaust guide boss. I'll have to get the heads machined or longer valves to make 1.4 rockers work. Straight cuts could also be on the cards. Then there's the freshly rebuilt IDAs on the work bench, but I doubt the heads are big enough. Things that make you go hmmmmmmmmmm. Disagreement, argument, suggestion and abuse is requested wtih this post. CYA CT3

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PAZZAN Wolfsburg Wizard

592 posts · joined Jan 2008 · 29 Dec 2009, 6:33 pm

#754532

anyone interested buying my car with no motor

hellbugged 48's and straight cuts

5,080 posts · joined Apr 2003 · 29 Dec 2009, 6:51 pm

#754534

❗........always, flip me a pm