when i start my truck it runs normal, as soon as it hits operating temp it starts sounding like a subaru and like its missing.

Details: 80 20r mild cam, recent rebuild, msd ignition, blaster coil, weber 32/36, header to 2.5", no smog. Only vacuum lines in use are booster line and distributor vac advance. intake manifold breather to valve cover is good. just did new head, valve cover, intake, exhaust gaskets. head was surfaced and passed leak down test. oil is still clean so no cracks in block.

Im guessing its carb related due to the change in running from cold to warm?
I am going to check for vacuum leaks tomorrow, but anyone had similar problems?

 

I think you are on the right path with the carb and vaccuum lines. As soon as i read the first line in your post, that's what I was thinking.

 

Yea check your carb and especially the adapter plate they are very weak and like to warp I run thick cork gaskets for this reason alone .also try re adjusting your weber per instructions . Two best suit your rebuild .Check for a fully operating choke plate make sure it's not jamin up . And then go for the intake manifold gasket to head check ..

I for one am constantly adjusting my weber double 34 synchronized its a pain in the ass

 

Your carb is electric or man. choke?I used too have a cranky old webber that would run sh!ty without the filter and once you put the filter on it was good. You could even cup your hand slightly over the carb and it would help. I'm thinking if you still have your stock ignitor try running that and see if it stops.

 

so i resealed my intake manifold today got it running at operating temp and the subaru missing went away! i sprayed some carb cleaner in the top of the carb while it was running and after doing this a few times at operating temp it seemed to run a little smoother, so i might just have a gummy carb. only problem now is i found a damn crack in my header and have a bad exhaust leak. haha i can never win with this thing.

Since i bought the truck from a friend i didnt get any instructions with the weber carb, i checked the choke though, i believe its electric, there is a wire going to a solenoid looking thing on the outside of the carb. i can manually get the choke to work and with a blip of the throttle it will shut off, but it isnt working to come on by itself and it does feel like its jamming up. is this common with the 32/36?

Thanks for the feedback, im gaining on it!

 

also what do you guys time your 20R's at with a mild build like mine? when warm and the distributor disconnected and plugged mines reading around 8* advanced.

 

You can find the weber tuning instructions on google . Yes that's a electric choke you have next time the motors cold and not running take the filter off and see if that choke plate is closed if its open tap the gas < motor off . it should shut then crank the motor and it should slowly open up as the motor warms .if it does it works as far as timing I'm about six to seven Ish hoses disconnected . Think webers like some advance . Depending on what octane u run two but I always keep mine advanced below 9 above 4

 

Right on so intake leak causes Subaru noise. Roger that for future references.lol.

 

Ill mess around with my timing and see if it runs better or worse between 9-4* normally when i retard it it wants to die so ive got to raise the idle. Ill check the choke, everytime ive taken the filter off the plates are full open. Ill check to see if they close on there own.

As far as i know bad vacuum leaks at the intake cause subi sound. my friends 22r rock buggy lost a plug for the booster vac line and sounded the same as mine haha