Spark Plug
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Instructor
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From: Crestview Fl
Spark Plug
The never ending spark plug question.
My 61 is burning rich with AC 45's. Now I know the 46 is unavailable unless you pay the high bucks on Ebay. I am running a Pertronix distributor/2X4s and was thinking about changing to NGK XR4 or Autolight 86. However when I check the cross reference guide the old AC45 cross references to the NGK XR4 and Autolight 86. How can the heat range be the same for the AC46/45 cross reference? I want to jump up a little on the heat range. I hope that made sense? Anyone know?
My 61 is burning rich with AC 45's. Now I know the 46 is unavailable unless you pay the high bucks on Ebay. I am running a Pertronix distributor/2X4s and was thinking about changing to NGK XR4 or Autolight 86. However when I check the cross reference guide the old AC45 cross references to the NGK XR4 and Autolight 86. How can the heat range be the same for the AC46/45 cross reference? I want to jump up a little on the heat range. I hope that made sense? Anyone know?
Race Director
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From: northern california
C2 of Year Finalist (track prepared) 2019
45 heat range is a good one to use. 46 (or equivalent) could end up being too hot..... years ago it was recommended for taxis which spend a lot of time just idling.
Find out why your engine is getting too much fuel and you'll be on your way to solving the problem.
Jim
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Army
There was a service bulletin way back about running the ACR46S in city traffic. They weren't just for taxi cabs. However, they are made of unobtainium; meaning you can't find them. Not for prices mere mortals can afford leastways.
Run the NGK-XR4....I've run everything else including the Autolite 86s....the NGKs cross over to both the 45 and 46 plugs - you'll notice the difference. I just put a set of NGKs in my newly acquired split window coupe.
Run the NGK-XR4....I've run everything else including the Autolite 86s....the NGKs cross over to both the 45 and 46 plugs - you'll notice the difference. I just put a set of NGKs in my newly acquired split window coupe.
Last edited by Frankie the Fink; Sep 25, 2013 at 10:24 AM.
Le Mans Master
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From: columbus oh
Spark plug heat range does not affect whether or not your engine runs rich or lean. Rich/lean is determined by the gadget supplying air and fuel to the engine.
45 heat range is a good one to use. 46 (or equivalent) could end up being too hot..... years ago it was recommended for taxis which spend a lot of time just idling.
Find out why your engine is getting too much fuel and you'll be on your way to solving the problem.
Jim
45 heat range is a good one to use. 46 (or equivalent) could end up being too hot..... years ago it was recommended for taxis which spend a lot of time just idling.
Find out why your engine is getting too much fuel and you'll be on your way to solving the problem.
Jim
,,,,however, if the op is looking for the 46, i think the champion h-10 is the equivalent but not for sure??,,,,
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From: Corpus Christi, TX
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From: Crestview Fl
Spark Plug
I did the air fuel flow deal. I just about have to lean one carb completely out. I did not want to go that route.
Thank for all the advice/recommendations. I believe I am going to go with the NGK XR4 and see what happens.
Frank,
I see you are still out there and kicking.
Thank for all the advice/recommendations. I believe I am going to go with the NGK XR4 and see what happens.
Frank,
I see you are still out there and kicking.
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From: Crestview Fl
Mortal
Frank,
I just notice you acquired a split window and mention the price of AC46's not for the average mortal.
If you still have your 62 and now have a split window you have have acquired status above us mortals.
Have a good one, good to see your still out there.
Rog
I just notice you acquired a split window and mention the price of AC46's not for the average mortal.
If you still have your 62 and now have a split window you have have acquired status above us mortals.
Have a good one, good to see your still out there.
Rog
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Army
Frank,
I just notice you acquired a split window and mention the price of AC46's not for the average mortal.
If you still have your 62 and now have a split window you have have acquired status above us mortals.
Have a good one, good to see your still out there.
Rog
I just notice you acquired a split window and mention the price of AC46's not for the average mortal.
If you still have your 62 and now have a split window you have have acquired status above us mortals.
Have a good one, good to see your still out there.
Rog
A LOT to learn about the '63 though - whole new territory
The previous posters are sharp guys but having driven a dual quad car in Orlando traffic for 8 years now...they do tend to idle rich and 'load up' some (hence the service bulletin); when running at cruise the back carbs primarys are doing the heavy lifting and so the fuel distribution isn't that greatest either. Just life with these cars.
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From: Greenville, Indiana
The Service bulleting mentioned "oil burning" which was probably due to the chrome rings used back then that either didn't seat or took a long time to do so. It also took into account the owner using leaded fuel. Hotter plugs would tend to clean off the lead deposits and the burnt oil deposits.
As I've stated before, the dual quads do tend to load deposits more on the rear four cylinders than the front due to poor fuel distribution when running on one carburetor. Since unleaded gas became universal, I don't think I've seen a fouled plug unless it was an ignition failure.
Jim has the right idea, fix the root cause of your problem instead of band aiding it with the hot plugs.
As I've stated before, the dual quads do tend to load deposits more on the rear four cylinders than the front due to poor fuel distribution when running on one carburetor. Since unleaded gas became universal, I don't think I've seen a fouled plug unless it was an ignition failure.
Jim has the right idea, fix the root cause of your problem instead of band aiding it with the hot plugs.
Team Owner
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From: Washington Michigan
Get the carbs set up with the stock-spec jets and metering rods (God only knows who's been in there before and what they did) so you get the mixture where it belongs and you can work with it. Spark plugs aren't going to make any difference, and certainly won't solve your carburetion problem.
Melting Slicks
Joined: Oct 2002
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From: St Louis MO
It's amazing how getting the carb right will make spark plugs look right and last. Compare high mileage plugs used in a computer controlled vehicle which holds the AFR at 14.7:1. Get yourself an AFR gauge and a vacuum gauge that you can see while driving on a deserted road. You may be surprised at how poorly your carb is tuned!
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From: Crestview Fl
Carbs
I should have mentioned the carbs are completely restored to specs by Dayton Carbs. They did an outstanding job, and they are setup right, plus I am running an pertronix distributor.
Thanks
Thanks
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Army
Daytona Parts got my original '63 WCFB about two days ago for the complete redo. It was past just putting a kit in it. They've done about 6 carbs for me over the past few years and, yes, they are excellent. The '63 has an old Carter AFB in it for now but it could use a rebuild too so I bought a kit from Daytona - all their stuff is ethanol resistant and top notch; can't go wrong with their parts.
Le Mans Master
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Get the carbs set up with the stock-spec jets and metering rods (God only knows who's been in there before and what they did) so you get the mixture where it belongs and you can work with it. Spark plugs aren't going to make any difference, and certainly won't solve your carburetion problem. I have my 2 x 4 set up on my 61 since 2001 and have not removed a spark plug since.
I did the carbs myself and I still have point ignition. I made sure the jetting and rods were correct and I lowered the float level a tad from spec.
I run Autolite 85's in my three cars.
Joe
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Army
I have the pertronix III distributor with rev limiter set to 5500 RPM and the NGK plugs gapped at .040 instead of the factory .035. I put in an adjustable vacu advance cam and did a custom advance curve with springs and limiter tabs. Car runs like a raped ape (for a 283ci that is!).
BTW I always tune idle mixture for highest vacuum then lean out the mixture by approx 1/8 to 1/4 turn on each screw that helps with idle richness. That's the last step for tuning the WCFBs according to the manual:
BTW I always tune idle mixture for highest vacuum then lean out the mixture by approx 1/8 to 1/4 turn on each screw that helps with idle richness. That's the last step for tuning the WCFBs according to the manual:
Last edited by Frankie the Fink; Sep 26, 2013 at 09:09 AM.
Team Owner
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From: Greenville, Indiana
Maybe your fuel pump is putting out too much pressure and overrunning the needle/seat(s)?
Race Director
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From: Beverly Hills (Pine Ridge) Florida
As another point of ref., I have been running Bosch platinum center electrode plugs for quite some time. This is with a good condition standard (single set of HD points) points dist., with dual AFBs on a warmed over 350.
I never have ignition, plug, detonation, or loading up issues.
One key point to note with points type dist. (for running @ high RPM) is to always set dwell at the max dwell setting to maximise the ignition coil saturation time. Yes, this puts more heat into the coil, and can cause a marginal brand to fail, but I have never had a Delco fail. And I still am running the stock Delco coil........
I started using Bosch platinum tip plugs when I was playing with turbos and superchargers, and always found them far superior to the equivelent heat range Champions (non-platinum) I was running previously.
Plasticman
I never have ignition, plug, detonation, or loading up issues.
One key point to note with points type dist. (for running @ high RPM) is to always set dwell at the max dwell setting to maximise the ignition coil saturation time. Yes, this puts more heat into the coil, and can cause a marginal brand to fail, but I have never had a Delco fail. And I still am running the stock Delco coil........
I started using Bosch platinum tip plugs when I was playing with turbos and superchargers, and always found them far superior to the equivelent heat range Champions (non-platinum) I was running previously.
Plasticman
Last edited by Plasticman; Sep 26, 2013 at 01:45 PM.