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how lean am i?

stage3

stage3

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take a look at the #1 spark plug pics...rattling the pistons on semi hard acceleration and running hot..up to 212 today..thought I was going to have to call AAA....3705's with 101 primary's..had 119's in there but went with the 101's after a suggestion...thinking to put the 119's back in..rather be fat than lean...650 roller...far from stock,,street driven mostly..change secondary's also??.089 and .077....fan shroud will be coming off..its a pos...blocks free flowing air at speed..car runs hotter at 50 than standing still..

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We run a 440 with stock cross ram, stock jetted 3705's in Phoenix, no issues driven it to Las Vegas several times.
Doug
 
I was going to ask, How does a shroud block air, but I then looked at your pic. Absolutely agree. Run a factory shroud with clutch fan.
 
thanks for the response...there were stock jetting for the 63 and 64 3705's..stage 2 and 3...here is a chart I found with goggle.....110 jets..for a 320 duration .520 lift factory cam..im .650 roller..so im going in the right direction with a .115--.119 jett.
1964, 426 Max Wedge Cross-Ram Fresh Air
Carb: Two Caner AFB 3705S carburetors
Manifold: Stock Max Wedge Cross-Ram
Manifold Modifications: one
Carb Specifications: Two Carter AFB 3705S carburetors
Left Carburetor
Throttle Side Diaphram Side
Primary Jet: 120-410 (.110") 120-410 (.110")
Secondary Jet: 120-392 (.092") 120-392 (.092")
Metering Rods:
PT WOT
16-76 (.066" x .053")

Right Carburetor
Throttle Side Diaphram Side
Primary Jet: 120-407 (.107") 120-407 (.107")
Secondary Jet: 120-389 (.089") 120-365 (.065")
Metering Rods:
PT WOT
16-76 (.066" x .053")

Note: Same jets used for increased interconnection manifold (10 in.2 and 55 in.1). See Figure D.
Air Cleaner: Ideal Entry

Special Note: The modified interconnection manifold shown in Figure D has not been proven to be better than standard. Also, it has not been run on the dynamometer to revise the above carb specifications. On the 1964 Max Wedge, the increased interconnection does not appear to be a performance improvement.

cams were very diffferant from 63-64..more cam...more jett..

BTW..the .101 jets were recommended for 63 motors..heres alink for the info..from mopar performance for anuone going thru what im doing to get it close..

http://moparsofutah.websitetoolbox.com/post/Mopar-Racing-Carburetor-Manifold-Calibrations-2603834
 
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WileERobby said:
I was going to ask, How does a shroud block air, but I then looked at your pic. Absolutely agree. Run a factory shroud with clutch fan.
Click to expand...
that's what I said!I pulled one of the fans they sent with the package..its a 755 cfm pusher sold as a puller!just ordered 2 spal 1500 cfm pullers from summit..with the new jetting,should be a lot better...need to get it sorted out..nov 4th entered in hotrodsatthebeach.com santa cruz beach boardwalk..last 1 of the year...
 
The stock 3705s used 104s in the primary with 16-76 metering rods which were .053" on WOT, the secondary throttle side was .089" and the choke (outer) side .063", this jetting is a great place to start.
 
stock 1964 stage 3,, 3705's had .107 in the primary's according to Chrysler's service update from dec '63..
went with the mopar performance update listed above that supercedes all others....110 primary's,,.092 secondary's..66-76 metering rods..rejetted today,will test and tune in the next few days...according to the seller I bought the car from..i have a .650 roller with 320-330 ex/intake duration..should be in the ball park..need some color in the above pictured spark plugs..

after installing the 1455 cfm fans..up from the 755's the radiator came with..blew the 20 amp fuse I had in it!..will install 30 amp units and test it all later..
 
i don't think your lean. plugs look a little dirty. i'd look at the step up springs first and then go after jetting. .119 is too fat. .104 or .107 with a 65/52 rod and .089 in the back is where i'd start. but, I think you should start with the correct step up spring.
 
Go back to 107's, maybe lower but start there.
Match your stepup springs also. Sounds like youre over running the circuit
 
I don't know, but I think I would like to know the kind of fuel before I tried to read spark plugs. Detonation? Would not some wise questions also be........compression ratio?........timing (cam and ignition)?......cranking compression?..........and again, fuel?

You need not answer, I'm quitting this hole engine building stuff for others anyway.
 
With the engine up to temp and idling loosen the metering rod covers a and twist them so you can see whether or not the piston/rod is in the down position. If they are bouncing around you'll need lighter springs hence my earlier comment about spring kits x 2. At idle they should be down but as soon as you give it gas the step up springs should now rise and stay fairly stable.
 
thanks for all the responses..
I put in the .110 primarys..as a starting point..i will check the springs at idle once I get it running..forgot about those..it started pinging pretty bad on the last trip out..but it also was running pretty hot with that pos shroud on it..which is now gone....timing is 36 total with 20 degree's initial..using the fbbo plate in the dist..running on California 91 octane pump gas..don't know compression yet.neither did previous owner who got the car from someone else..motors coming out soon anyway.but would like to have a good tune on the carbs for the replacement.but cam timing with intake closing atdc should have bled off most compression for detonation..in theory..
 
With unleaded pump gas the spark plug will have a clean, white ceramic all the way down to where it is cemented to the iron. There, at the bottom, the ceramic should have a gray ring, about 1/16" wide. That 1/16" gray ring will indicate a proper fuel mixture. You cannot properly read the fuel mixture, using unleaded fuel, with old brown ceramic spark plugs. It requires fresh plugs, a bright light source and a magnifying lens.
 
stage3 said:
thanks for all the responses..
I put in the .110 primarys..as a starting point..i will check the springs at idle once I get it running..forgot about those..it started pinging pretty bad on the last trip out..but it also was running pretty hot with that pos shroud on it..which is now gone....timing is 36 total with 20 degree's initial..using the fbbo plate in the dist..running on California 91 octane pump gas..don't know compression yet.neither did previous owner who got the car from someone else..motors coming out soon anyway.but would like to have a good tune on the carbs for the replacement.but cam timing with intake closing atdc should have bled off most compression for detonation..in theory..
Click to expand...
I always look at the intake valve closing point when trying to juggle cylinder pressure and that is after bottom dead center. even at that I think juggling valve closing is only a marginal cure. I suspect you just plain have too much cylinder pressure for 91 octane. doing a compression check will give you some idea.
 
lewtot184 said:
I always look at the intake valve closing point when trying to juggle cylinder pressure and that is after bottom dead center. even at that I think juggling valve closing is only a marginal cure. I suspect you just plain have too much cylinder pressure for 91 octane. doing a compression check will give you some idea.
Click to expand...
Wait a minute, that makes too much sense.

Better I think to just add air pressure in the front tires. Less rolling resistance, the engine won't have to pull so hard, and the detonation might go away.
 
IQ52 said:
Wait a minute, that makes too much sense.

Better I think to just add air pressure in the front tires. Less rolling resistance, the engine won't have to pull so hard, and the detonation might go away.
Click to expand...
sometimes ear plugs and turning the radio up diminishes detonation.
 
heres a thought...air up my tires to 60 psi,,always go down hill...and only use my little toe on the throttle! no more ping!
 
Those plugs are what,,,,after driving around for a while or clicked the key off after a WOT run?
 
HEMI-ITIS said:
Those plugs are what,,,,after driving around for a while or clicked the key off after a WOT run?
Click to expand...
driving around putting easy miles on the new 4.56 gears..pulled the plug after entering the shop...stepped up to a final jett sizes of ,,.107/.095/.089,,65-52 rods.and orange springs..will test tomorrow..with new 1500 cfm fans...should be much better....and after testing...I have access to VP 110 race gas that will mix with pump gas to bring octane up a little..if nessacary...will try all other avenues 1st before I support the race gas industry before the motor change...mainly want the carbs well within the ball park before the marine 426 stage 3 motor goes in..
 
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