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Hello all. After a long winter, the 2002 is back on the road. I hit a friends shop with a Dynotech dynometer a coulpe days ago and here are the numbers. Remember, the 2.0 was rated at 98ph when new from the factory. That's 98 crank hp. As an overview on my motor. I have 90mm, 9.5:1 pistons, 292 cam, 1mm over-sized valves on both sides. Stahl 1.25" primary long tube header. 2" exhaust from there. Ireland Engineering intake manifold. 3/4" air horns under K&N filters. Weber top mount linkage that has been upgraded a bit. Last fall, my motor was running VERY lean with the set up that the carbs came with (fitting the story in the type 3 section of the copied document below) Stumbling off idle, and while driving it hated being held a cruising throttle. Over the winter I went through and base-lined the carbs to what the history doc below described, and a bit on the larger displacement side... I swapped in .11 emulsion tubes, had .7's. swapped in 210 main air correctors from 200. 155 main jets from 135. 62 idle jets from 55. I went to the rich end of the spectrum, figuring I can get readings from my yet to be installed wide band AFR system, and then hand drill the smaller jets to really dial the jetting in. But then I found this audio track about tuning with the emulsion tubes and wondered if the .11s could just be drilled out a touch.. So once I get the accelerator pumps dialed in to get rid of the lean spike, and get the AFR to 13-ish on the high revs, I might just see 120 whp. Thoughts on what you see in the dyno picture? Copied....someone here wrote this I believe. Type 3 DHLA40F-G-H-N-R-S models. These are called emission completely different to the DCOE science, but noone really understands them and tries always to tune them like the early models. These differ because they have more progression holes and use the idle jet to feed most of the cruise phase and low rpm/low TP area of the engine AT ALL TIMES when the main jet isn't in operation completely automatically no jetting needed. The idle jet has a very large fixed 2.2mm air feed, you cannot tune this phase of the carburetor for length like the others, but here lays the secrets.... The idle jet doesn't feed from the float bowl, it feeds directly from the main jet stack, what happens after this is what gives these Dell'Ortos the sweetest road behaviour (what 25years of research came up with and not just for emissions) and dead easy tuning, you see when the main jet starts to emulsify fuel in the tube, the idle jet is feeding from it, so the gassy airy fuel shuts down the idle jet and sucks backwards yes BACKWARDS through the idle!! using every drip of fuel efficiently without ANY waste in circuit cross over where one is going after the other...this happens the moment the main jet fires, so there is NO need at all to tune the length of the progression and idle phase. This is pure magic they are automatically calibrated, you simply keep the idle jet above 59 up to 62 and not make the mistake of fitting numbers suited to the early DHLA or DCOE - with this simple technique you can tune anything from a 1300 to a 2000cc without really doing anything. The emulsion tubes in these carbs are always 8-10-11 and have to stay that way - which are really rich and have a hole straight down with loads of air holes, these atomise the fuel to an massive degree, also they have to be used cause the idle jet will not run correctly using the DHLA40-E type tubes (1-6-7-5) as the idle jet needs these airy tubes to function and cut out as designed...Usually people ram the DHLA40 idle holders with air holes in these carbs add the 1-6-5-7 style tubes and wonder why its a massive lean spot off idle, cause they missed the point completely!...These carbs use a .3 vent which has a very small signal tube to the main jet stack, this is because the holey tubes are basically ready to go from about 1250rpm (on my car using an 8tube 1 vent it was on the mains at 1250rpm!) so the holey tubes need holding back with a signal killing venturi...These carbs are wicked if you want bolt on power, they tune themselves! The early types are better in respect of punch and tuneability on odd applications but dont' really do anything these late types won't on all but the best engines...I have run em all! These carbs will give the maximum power available on any engine if you take time to tune them right, but they are a bit more suited to standard motors over 1500cc, motors with mild cams or standard cams and they operate best if you are using 30-33 chokes, they hate race engines, mad cams and mad chokes cause they they are designed mainly for hot production engines with a clear pulse strength to suit the retarded venturi and tubes - great where silk town driving and alike is paramount and you do commuting or just sunday driving, they also give superior economy to the early types.

I would like to speak with you directly via email or something. I have a motor being built, it was supposed to be finished a month ago (the bastards), and now I have two weeks before an event that I host. Motor should be ready to install this week. I have a set of DHLA40-H that have very had little road time on them(2.0 alpha) with the original owner, and look to be in excellent condition.. I was the first to turn any screws. I would like to talk to you about baseline set up... jets, etc. I have all the numbers that I could find from the set now. Just need input. Jetting recomendations, best practices for syncing the H type, etc. P.S. While I have the basic knowledge...I'm a total side draft noodie. And I'm short on time.. Can you shoot me a message at jasontgipson@gmail.com??? Thanks so much. M10 specs: 47mm intake and 39mm exhaust valves. (both 1mm oversided) 292 duration cam 9.5 compression ratio Shorty header, not long tube. 2" exhaust pancake filters on carbs TIA -Jason