So i've decided to ditch the points system and replace it with a slightly more modern approach being the electronic distributor. To my understanding this is pretty much a bolt on upgrade, but im curious as to if pre 1971/post 1971 emission control engines will have different effects that need to be adjusted in order to achieve maximum performance. Since im also planning to boost my comp ratio to 10.5, i must alter the static advance and possibley a spring/weight? Thanks for any insight..

,Aaron

What to do with the advance curves will depend on which distributor you start out with. The desirably-curved '76 distributors are still showing up new on eBay with fair regularity. You may want to skip the Mopar ECU and go directly to the see HEI upgrade.

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Too many people who were born on third base actually believe they've hit a triple.

Some distributors have different governors, 7R, 9R or 15R etc.....My 74 has a 15R, which means the slots are longer for more weight movement. The slot will dictate which springs will be required to meet your goals. For mileage the 15R is great. For racing the 7R or 9R would be fine.

Let us know if your going racing or building a torque/mileage car.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

I plan on installing dual exhaust w/ shorty headers, porting a 10.5 comp ratio head, using a cam with 276/260 something cam with around 54 degrees overlap i figure, and a 490 cfm 2 barrel on a super six manifold or something like that. Nothing to serious, but this is going to be a streetable engine if you catch my drift

Sounds like you want some mileage to go with that setup. I would get a 74 to 75 distributor core with the 15R governor in it. That way you have some room to dial it in for performance and mileage.

For example here is my set up.

New 1974 electronic Distributor re-curved with a red primary spring and extra long looped secondary spring from a 400 big block distributor. 340 distributors are good to rob springs from too. Using a 15R governor with a 11R V8 vacuum advance screwed in 4 turns, (VC-208 11R can $10.26 at www.rockauto.com). Blue Streak cap, MO-3000 Echlin rotor, Chrome Blaster 2 coil, MSD Blaster .85 ohm resistor instead of the stock MOPAR resistor, Orange ECU and 8mm Blue Summit wires, NGK UR4/6630 plugs gapped at .040. Timing set at 16 degrees initial, 16 degrees mechanical and 20 degrees with the vacuum advance for a 52 degree total at 2500 rpm.

For cruise at 50 mph I am 2000 rpm, at 60 mph I am 2500 rpm. On the freeway I am between 65 and 70 mph.

Tuning: Adjustable vacuum advances can be adjusted to when the advance starts, not the amount. The part# number on the can or number on the arm indicates the total amount of advance x 2.

Using a 3/32 allen wrench you can adjust the advance to where you can plug it in and unplug the vacuum line and see zero or little timing change. For me that is about 3 - 4 turns.

For reference, at idle with my cam I am at 18 inches vacuum. So there is no advance from 18 inches or less. Then you have it set right on. You don't want the vacuum advance to kick in too soon or it could over advance and surge or when the engine is too hot, causing it to ping. At cruise I run between 15 and 22 inches of vacuum. At 15 inches vacuum and 2000 rpm puts me right at 30 degrees timing, 19 inches at 2500 rpms puts me about 45 degrees. Letting off slightly say 20 inches takes it on up to 52 degrees.

The MSD Blaster coil swap provides 10 volts to the coil for good spark.

With the little one barrel it will light up the P235 tires at the slightest aggressive pressure on the gas pedal. That is with a 2.76 gears in a 8 3/4 posi-traction rear end. With a four barrel you would be in good shape for a long burn out.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG