Altitude jetting for a Webber DGAS 32/36

[jtoro]

Hi everyone. I have a 1968 F engine FJ40. I put a Weber 32/36 on it and even though it's working ok, I have a feeling that jetting it accordingly to the altitude would make it better.

I generally drive it on my hometown (located at 5,000 ft.) and drive it regulary up to 6,500 ft.

The mixture is aproximately ok (judging by the color on the spark plugs) but I still think that such an altitude requires smaller jets. Does anyone have a table or such that I can use as a guide for the sizes?

Getting them down here is expensive and I would like to buy only the ones that are suposed to work.

Thanks

 

[jtoro]

Bump, Help please

 

[PhilC64]

The FAQ is your friend! Good luck!

https://forum.ih8mud.com/40-55-seri...er-carb***-adjustment-thread.html#post3179086

 

[fireflyr]

Jtoro,
I have a '67 with a '73 F.5 and a Weber 32/36 that I just jetted. I live at 4000' and here are the jet sizes I came up with, I would expect yours to be a bit leaner.

Main circuit:
idle 90
main 150
air corrector 170

secondary circuit:
idle 60
main 175
air corrector 180

Make sure you are getting the numbers you need on the idle mixture screw (out 2 turns) and no more than 1.5 turns in on the idle speed screw. If you get these set first move on to the main jets and air corrector jets. I bought the high altitude kit from www.carburation.com and was able to stay within the jets provided and what was in the carb.
I also made a chart and started recording the changes and making notes on driveability. There is alot of good info on other forums for Webers. Just Google weber 32/36 jetting.
Good luck.

 

[jtoro]

Thanks everyone, This should solve my question, or else I shoud quit trying

 

[fireflyr]

Thanks everyone, This should solve my question, or else I shoud quit trying

Make sure to only make 1 change per test drive once you get past dialing in the idle jets. I live in a mountainous area with a freeway nearby. When I test drove a change or adjustment I would check low speed response (tested idle jet and primary main and air corrector jets) and lugged it down to almost a stop then would apply full throttle to see if it hesitated or backfired. I would then test it on an uphill section of the freeway (60 mph). If I was constantly into the secondaries or if it wouldn't maintain speed I'd make a change. I started out rich and adjusted down. It's a tedious process.
The biggest change I made was in the primary idle jet. A #60 was installed in the carb and with that the idle mixture screw was out 4 turns and the idle speed screw was turned in all the way. Once I increased the size of that jet the rest of the jetting started to fall into place. I would suggest buying the high altitude kit. It saved me alot of time and money ordering jets.

 

[jtoro]

Just got the high altitude kit from LC Engineering. Will start testing tomorrow and post updates. Thanks to all.