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I'm gonna need one of these one day. I have a spare 155 head and this outlet is what I've been thinking about. gprocket - did you build this?
Formula GT Germany makes these. but a competent welder should not have difficulty making something like it.
 

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The carbs are DHLA40, the idle jets are 50 set in emulsion tubes 7850.1 the carb tags say 5233.P rear and 5234.A front, which I believe makes them correct for the engine and year. I’m going to speak to Eurocarbs UK and find out what jetting was standard for the 2L engine when new and see if they have any suggestions on jetting it now.
I was asking because the main E. Tube for a Dellorto without letter and for 2L engine should be 7772.7, in the chart 7772.5 E.Tube correspond to a 1750 and 7772.1 correspond to a 1.6 engine,

do as being suggested, check cam timming first, get your basics and them you vcan "fine tune" it
 

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Type numbers missing

I was asking because the main E. Tube for a Dellorto without letter and for 2L engine should be 7772.7, in the chart 7772.5 E.Tube correspond to a 1750 and 7772.1 correspond to a 1.6 engine,

do as being suggested, check cam timming first, get your basics and them you vcan "fine tune" it
@ quadrifolio:

In your posted list the reference type numbers are missing as well as the appendixes DHLA E/F/G/H ect.; the data I´ve provided are coming from a detailed origin Dell´Orto listing.
 

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@ quadrifolio:

In your posted list the reference type numbers are missing as well as the appendixes DHLA E/F/G/H ect.; the data I´ve provided are coming from a detailed origin Dell´Orto listing.
true, its only till ´72 thats why its missing all the detoxed versions with letter suffix but its good enough for him like his version is the older one without letter suffix so he may have a starting point
 

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Many thanks to all. Spoke to Eurocarbs today, very helpful and didn’t try selling me anything. I’m now trying to find someone in the UK who understands Alfa’s, Cams, 123 ignition, Dellorto carbs. Harder than you’d think so I’m also self educating hence the rather foolish questions. Any UK recommendations greatly received.
 

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Many thanks to all. Spoke to Eurocarbs today, very helpful and didn’t try selling me anything. I’m now trying to find someone in the UK who understands Alfa’s, Cams, 123 ignition, Dellorto carbs. Harder than you’d think so I’m also self educating hence the rather foolish questions. Any UK recommendations greatly received.
Just down the road from you. They do all our RR tuning...

MEK MOTORSPORT - Home
 

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Jim, this engine has a matched pair of Jim Evans 11.2mm cams on the inlet and exhaust. It’s been suggested by several people that using identical cams on the inlet and exhaust is not the way to go and while the Jim Evans 11.2 mm cam is good as an inlet, it should have a different cam on the exhaust, possibly even the original 105 4803 200 01 which I think is 10.06mm. If you feel you can comment on this, I’d love to hear it as all knowledgeable info is greatfully received. Thanks
 

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I will use the motronic Spider 4 ex cam, like this cam is a truly ex cam with 9.6 of lift and 222º @ 0,050 inch and diferent lobe profile than intakes
 

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Richard Jemison
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Cams

Jim, this engine has a matched pair of Jim Evans 11.2mm cams on the inlet and exhaust. It’s been suggested by several people that using identical cams on the inlet and exhaust is not the way to go and while the Jim Evans 11.2 mm cam is good as an inlet, it should have a different cam on the exhaust, possibly even the original 105 4803 200 01 which I think is 10.06mm. If you feel you can comment on this, I’d love to hear it as all knowledgeable info is greatfully received. Thanks

Never take "some people`s" advice!

You will NEVER get proper valve events using the same cam on intake and exhaust! The intake cam has a different need as to CFMs and valve events relative to the exhaust where late opening and early closing to lengthen the power stroke, while closing early enough to prevent P to V issues, while having high durations during the "open valve" (from .040"- .400" lift points.
 

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Quadrifolio, thanks I’ll look at it. Alfar7 that’s sound advise for life not just cams! Do you have any suggestions please for a suitable exhaust cam to pair with the 11.2 mm cam on the inlet? Thanks
 

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Richard Jemison
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Hmmn...

Well I`ve never heard of Jim Evans or his cams.

If they are the ones in in an earlier post those don`t seem to be modern cams, and a 108 LC & LAS is too wide for good performance.
Typically LC`s on intake should not be more than 104 and same for the exhaust. for street applications.
If you want to see my PDF file of cam designs, in a lift-duration numerical format, so you can see what you are buying send me an email. ([email protected])
All of the factory cams have been camdoctored and are in this PDF file.
Rj
 
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