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Unfortunately when i rebuilt my engine this time last year I changed too many things to isolate the effect of each component. I changed heads, cam and manifolds all at the same time.

The old cam with 1.25s was super close on paper to the webcam 109 with 1.1s (= W125). The old heads (unported 044s) had the same size valves and a similar port volume. But the comparison here lies in the effect that DRDs attention to detail makes. I can still get both heads flowed to check. The old manifolds were super short and 44mm at the carb side rather than the universal 48mm fit on the new tall manifolds.

I didn't get a chance to put the last combo on the dyno, because the lifters wore out on 1 lobe after 1500 kms, but I felt a big increase in torque. The previous combo needed to be driven harder. You had to get the engine up in the revs even before you let the clutch out. It was good for a 14.9 second quarter on a hot day with a stock gearbox. The new engine would respond from anywhere over 2500. You could just stomp on the throttle and it would be on song.

I chose the mini D-ports because I figured they were the best for the 1915 capacity. Sure the engine needs to breathe but I've seen quite a few similar engine combos and airspeed seems to be the key. On a bigger engine I'd probably go for some bigger ports, more flow and some longer valve stems. My valves will only lift to .500 so that rules out the K8 and K10 with 1.4 rockers which I was also considering.

The compression is not really a problem. The engine oil temp is fine on the road but on the track it gets to 120C on the 4th lap depending on the circuit. I'm putting a cooler up the front in the air this time instead of above the gearbox.

The 044s were 10 years old and cracked. I only used them for an experiment after I was unhappy with my street eliminators. A couple of the cracks were peened over and 2 were welded up before I put them on my engine. After about 9 race meetings and about 10,000 kilometers of punishment the 2 of the chambers ended up losing some metal between the valve seats.

For cooling I don't run the front tin because I figure extra cool air comes from under the car. I use an aftermarket 36 horse shroud and the rear of the engine lid is popped open 1 1/2 inches at the bottom to let out hot air. I've also used an original 36 horse shroud with a 1500 fan which seemed just as good as the std dog house shroud with the heater outlets cut off it. The aftermarket 36 hp shroud with doghouse seems good but that could just be because of the new head, cam & manifold combo.

I chose the W130 cam because I want to buzz the engine up to7500 rpm. I found with the last combo that although the engine was running out of cam after 6500 if I revved it to 7000 or in some cases just held it in 3rd it was better for the lap times. With another 500 rpm and some extra hp it should be a benefit. My car only weighs 750 kilos and the ratios of the stock late 1300 box are quite close. It should work.

I've haven't seen a stock rocker arm fail yet and I've seen a few aftermarket ones have problems. Some don't have proper oil holes or something. I broke a rocker clip at 6500 rpm 2 years ago and since switched to CB Performance bolt together shafts. I have some 1.25 rockers but I couldn't get the valve geometry to look as good as it did withthe 1.1s. The downside with having a lot of lift at the cam was having to clearence the lifter bores but that seemed more of a counter sinking exercise rather than spot facing.

I'm no expert by the way. I'm just a backyard hack with a lot of passion for developing my combination. I like the Italian feel of the webers on a high revving 1915 and I'll probably stick with the combo.

With regards to heads for a turbo, I have no idea. A good port design for a naturally aspirated engine may not be ideal because the air is being pushed and not pulled. I've got heaps of respect for the performance of turbo vw engines and the patience and engineering ability of those that can make it work. Just before Christmas I went in a Type 3 wagon with a 2.3 liter Type 1 with a turbo and injection. The engine is built to rev to 7000 plus but it was still being run in and limited to 4500. It pulled so hard and so easily and would leave my car for dead without sweating. I can't imagine what the engine will be like at full revs. Apparently it's just waking up at 4500 and this guy was changing gear. Sorry, I'm no help with the hair dryer. Hmmm what would that do to head temps?

Sorry for the long post, I had to get it our of my system. I work for Yokohama tyres and nobody is interested in cars!

CYA CT