parshal

I've got an '83 22r with a stock (newly rebuilt) carb. It's got a 119 main jet. I live in the Denver area around 5000 - 6000 feet. I'm wondering if dropping the jet a few sizes will increase my mileage and not hurt anything. The guy at an import carb rebuild shop said that the stock jets are fine at Denver's elevation but you'd definitely need to go smaller if you went up any higher.

Thoughts? I'd like to increase my mileage, if possible.

kyle_22r

does your truck have the HAC(high altitude compensator) on the passenger fenderwell? it looks like a little round thing with 3 or 4 hoses going to the carb. if so, you shouldn't need to play around with jets, as this device leans out the mixture at altitude(and apparently works very well from what i've heard from most people).

if not, dropping a size or two in jets might help your performance and mileage. how do your spark plugs look? if the insulators are rather dark looking, you might consider rejetting.

parshal

No HAC on this truck.

It had been running rich enough to fail emissions until I rebuilt the carb. It passed but is still a little high. The plugs are new. The old plugs were "rich looking" pretty quick but that was with the old carb.

How far should I drop the jet? I know a place with replacement jets for $10. I think they had a 116 and 114. I'm just not sure how much you can drop it before it goes too lean.

fourwd1

I'd drop down one step at a time till it runs good.

INFINITY

any word on the jets you went with?
i live up at 5000-6000ft as well
what size secondary are you running?

parshal

I left them as they came and it runs fine.

INFINITY

what was the stock secondary main jet size? i am not sure who has messed with my carb before me. thanks

parshal

I really don't remember. I want to say 15 but I'm sure I'm wrong.

'86Owner

Hi, Does your carb have air jets? If it does it would be better to increase the size on those instead of droping the main jet size that way you don't lose power.

'86Owner

Whoa, I didn't even see the date on this thing lol. Well...