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Tue May 20, 2014 9:40 am

I've got a "new" engine that's really a couple years old by now but hasn't really run much yet because of what i suspect to be carb issues. Here's the info on the engine:

1915cc (94mm pistons and 69mm counter-weighted crank)
Engle 110 cam
Hemi-cut heads (I know that was possibly a poor choice, but it's what I'm working with.)
Stock sized valves with dual springs
Bosch 009 distributor
1.25:1 rockers
1.5" exhaust
Used dual Weber 40s (28mm vents, F11s, 115 mains, 50 idle, and 180 air corrector)

When I have gotten the carbs adjusted evenly in the past, using the snail gauge and all, it's idled great, but when I try to drive it, it'll get up in the rpms to around 2500 and then it sputters and won't accelerate any more at that point. I've tried setting it to various timings, each time readjusting the carbs, but each time it does the same thing. By the way, when it's just sitting and I rev it, it goes past 2500 rpm and comes back down nice and smooth. They also both leak a bit out of the middle where the throttle shaft connects to the little lever thing.

A friend of my dad's said I should just get new carbs and that he's never heard of anyone having any luck but bad luck out of used carbs. So my question is, should I break down and just get new carbs, or does this appear to be a fixable problem? Thanks in advance!

Tue May 20, 2014 1:49 pm

Yer jetting is all wonky, try a 55 idle/200 air/ f-ll e-tube/ 130-135 main. Check the float settings. They seem like there jetted for a stock 1600....Sounds like you might have a vac. leak around the throttle shafts, are they sloppy?also your exhaust seems big,try a 1-3/8" it sounds like it is starved for fuel (small Mains)

Fri May 23, 2014 9:50 pm

Thanks for the reply. The jet sizes were recommended to me by John from aircooled.net so, no offense intended to anyone, but I'd like to get more opinions as well to see what the general consensus is before I go out buying things. Incidentally, however, I have had another suggestion to increase the mains. Also, webebuggin, I'd like to know your reasoning for the changes, so I can better understand the jetting.

Sat May 24, 2014 6:01 am

What Webeuggin said will put you very close, That is what is in my 1835 and works great..115 main is too small

Sun Jun 01, 2014 8:25 pm

Thanks for affirming what was suggested. Maybe there was some confusion with John about the size of the engine. I may have mentioned that I previously had a 1600. I'll try the bigger jets and hopefully they'll work!

Mon Jun 16, 2014 8:48 am

Hello again! I received the jets that I ordered (130 mains, 55 idle, and 200 air) and finally got this thing running pretty good! I've got it adjusted pretty well but it's still just a bit lean on the upper end so I'll be up-ing the mains to 135 to see how that does.

Now I've got a question on timing. I set it at 7.5 BTDC as normally prescribed for the 009. I've also tried 10 BTDC and 12 BTDC (a suggestion from John @ac.n). So far, it seems that 7.5 is working the best. This is probably a complete beginner question, but how exactly do I know where to set my timing? Is it just a matter of trying different settings? Also, do the carbs need to be readjusted each time I change the timing?

Tue Jul 15, 2014 6:59 am

Well I got the jets all in there and everything tuned up and finally drove the bug for one day! Then the next day, the driver's side carb flooded on me. I adjusted the floats and they seemed to be working fine, but it flooded again when I tried to start it. What could be causing the flooding? I have a carter carotor fuel pump (the second one down on this page: http://carterfuelsystems.com/fuelpumps/universal_fp.php). I've read of other people using this same pump so I wouldn't think it would be sending too much pressure. Any thoughts?