Roger Bulla wrote: > Has anyone tried these heads from CB Performance? They look like they have > better air flow around the exhaust ports and maybe better quality control?<
Looks like maybe they have swapped to the "Chinese castings", which are improved over the CB 044 heads that came on N891JF. These are essentially what I bought from DRD Racing. I've done a lot of photos of these and several other choices over the last few weeks, having replaced my heads a week or so ago. See http://www.n56ml.com/n891jf/vw/ for more on this. It's a comparison of several different heads and their air passages. I was happy with the quality of the DRD heads, which looked very similar to the ones in your link. I've put two hours on them so far, and the thing still runs hot, so I'm on a baffling witch hunt now. I need some "conformal" fiberglass plenums on that thing like I have on the Corvair. I'm still looking for ideas on "what works" in various VW aircraft installations, because what I have isn't working. I took off in 95 degree temp yesterday, and after idling to the runway and a quick runup, it was at 400F as I turned crosswind, and I wasn't even at pattern altitude yet! Baffling is pretty tight on this thing, but what I don't know is what's going on in flight between the top of the cowling and the fiberglass/silicone seal. That's my main mission for the next three days until I take off for OSH. One more thing I'm going to do is wrap those hot exhaust pipes (just inside the inlet) with insulating wrap. No sense in preheating my inlet air... Mark Langford, Harvest, AL ML "at" N56ML.com www.N56ML.com
