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StabnSteer
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Hi all,

I've come into possession of my dad's 74 JH and it happens to be rather over-carbureted with 45DCOE9's on it (IMHO). He purchased, but didn't install, the anti-popping spacers from the club store and I figured it wouldn't hurt to try them out.

The Webers are mounted to the manifold with a rubber (maybe plastic?) anti-vibration spacer...does one retain this spacer when installing the anti-popping spacers...and if so, does it matter if the spacers are on the carb side or the manifold side?

Thanks all!

--Erik in Kansas City

Dan (Florida)
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If the engine isn't making a popping noise, I would leave it alone.  IMHO popping comes from  lean mixture or overworked overheated engine.  I installed dcoe 40's  and don't use the anti-popping spacers, but did put in extra thick gaskets.  I had some popping untill the lean jets were corrected.  I'm sure your dad (or somebody) went through long hours jetting and plug reading to get the best performance from the 45's .  Even when they are almost perefect, Webers are still a little burbley at  around 3000 rpm (the transition point between low speed and high speed jets).  Also make sure your mechanical advance (if you still have one) in your distributor is working smoothly.

hth,  Dan

 

StabnSteer
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Thanks for the ideas!

I have been curious about the definition of "popping"...In my case, I'm talking about what sounds like backfiring through the carb during mostly steady-state driving. Is that what folks mean? Deceleration and acceleration are just fine - its only when you're on a flat surface and trying to maintain a single speed they make the popping noise from under the hood.

As one might expect from an overcarbureted engine, these 45's are like driving my old race cars...that is, they are on or off with almost no progression. However, when they are on, oh boy, do they ever pull! It does make it hard to cruise at 55 down the highway when you are pretty much having to either accelerate or decelerate - there's no giving it half-throttle and maintaining speed without the popping, and anyway, half throttle doesn't really do much.

And yes - my dad spent lots of money to get the carbs tuned...but I would admit, the tuner was an old racer who is ornery enough to likely have tuned them a bit more to the side of performance. I saw one jetting posted here on the site, but I believe it was for a Weber 40. Maybe I'll find someone who'd like to trade the 45's for Dellortos (hint, hint).  :)

(waiting for the August heat to dissipate)

--Erik
Kansas City


Dan (Florida)
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I wouldnt swap out because of popping!  You may get into something even worse. Find a weber tuning site and get familiar with the jetting system and then go looking for a lean cylinder. You probably have a low speed jet  or two that is too small. Pull the plugs and look for a light grey color and correct that to a medium grey. Either buy larger jets or find a mech or machine shop with a jet drill set and drill out one size larger. I'll probably hear about that but it is quicker and cheaper, and you can always buy the correct jet later.  Also check the jets for debris which can lean out a jet.

you don't have anything else to do untill it cools off!

StabnSteer
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Thanks, Dan...I'll check the plugs and see if they do point to the lean condition. Considering what I'm experiencing with my foot as I drive, what you suggest makes sense.

...now to find my magnifying glass so I can read the jet numbers and know where I stand...  :)

--Erik

jensnhealy
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Give me a call. I'm in downtown KC and have 45 DCOEs on my car with jetting that has served me well, both on the street and at Heartland Park. Be happy to pass on my settings.

Scott Robinson

816-728-2614

pbahr
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Hi guys,

I have 45's on YELODOG, but the engine is tricked out a bit.  Weber setup is below.  Don't know if these settings would work on a stock engine.

Pete

Displacement ..........    2.2 L
Size ........................... 45DCOE- 9
Choke.......................... 36
Main Fuel Jets ...........  135
Main Emulsion Tube ...... F3
Main Air Corrector ........ 180
Idle Jet .......................  50F9
Starter Jet…………….. 60F5
Pump Jet ...................  45
Aux. Venturi .................. 5.0
Pump Discharge ....... ???
Accel Pump Jet…….. 45
Accel Pump Spring ... ???
Accel Pump Rod ....... ???
Needle Valve ............. ???
Float Level ................. ???
Fuel Pressure ............ 2.5 psi highway, 3.0 psi track.  Set by regulator.

 

1. Cams:  High performance, custom grind, by West Coast Cylinder Heads (Richard Reyman).
2. Compression:  11.1:1
3. Heads:  Ported/Polished and flow matched.
4. Valves:  0.180 oversize.
5. Ignition:  Electromotive HPV-1 (Crankfire)
6. Plug gap:  0.040 in
7. Timing:
 • Idle: 5 deg
 • 3000: 28 deg
 • 8000: 30 deg
 • Rev limit: 7000 rpm

 

Greg Fletcher
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You will experience better drivability with Dellortos for a street Jensen Healey, I'd only use Webers on a track car myself. Ok, Pete, I do remember your car does drive pretty awesome on the street, but it is not your typical Jensen Healey by a long shot. The Dellortos offer a sillky smooth progression throughout the range that Webers cannot match.

On those anti-popping spacers- they are not a magic bullet to correct any pre existing fuel delivery or inadequate design problems. All they do is prevent the o-rings from slipping out of place during installation (since they are a one piece assembly). As it's hard to see if the original plastic and o-ring set ups are actually assembled correctly, the anti-popping spacers just make installation a no brainer.

pbahr
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Wonder of wonders - after about five years, I finally performed some preventative maintenance on YELODOG:
  • Carb balance was still quite correct.  Used my new German device - much better than that thing with the floating ball.
  • Plugs were fine but I put new ones in anyway.
  • Timing was spot-on - well, I do have crank fired ignition !
  • Checked cylinder pressure:  All cylinders in 185-195 psi range.  Just like new.
  • Adjusted idle mixture via the pull-plug-wires method and there was some change in performance - below.
Actually, the real purpose of this post is to confirm that the Webers do suffer from progression problems.  THE IDLE MIXTURE ADJUSTMENT MADE A MARKED IMPROVEMENT ! ! ! !

Perhaps some Weber users reading this post might also get an improvement.

Pete



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