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Working on the 620 (Yoyo)


Cosmonaut

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20160806_112223_1.jpg

 

This photo is as of today, changes from the last photo;

 

1. All new brake hydraulics.

 

2. Brake Booster n Master cylinder from a 720 altered to mate.

 

3. New brake hardware.

 

4. Lincoln Mirrors.

 

5. New Stereo, boxed speakers.

 

6. New Tires (to be mounted on Turbines)

 

Hopefully I have gathered the proper secret ingredients.

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20160806_112331.jpg

 

 

This is a remote igniter EI distributor and it needs the remote 'box' located beside the glove box in a 620, for it to work. Alternatively you can wire in an HEI module from an old GM mullet mobile. Be sure you get a '78 or newer coil that can make use of this higher energy set up.

 

If it's an '80 720 it probably will fit but later boosters were so large a diameter they would hit the clutch master and the steering column under it. To fix this the booster was mounted on a pedestal about 8" forward of the firewall. This won't clear your L series intake and air filter very well. The later 720s had the carb on the right side of the engine. .

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Brake booster was off of an 80 720. I had the mount cut at the firewall bolt on from both the 720 and the 620 with the 620 wall mount welded on to the 720 booster pedastal. (same welder that disappeared with my F10 struts), he had done some great work for me.

 

Will be going the HEI route, thanks for the information on the coil.

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Only way to keep the compression up with a W53/L16 is flattop pistons... which you may have!!! Nice!  Otherwise the compression would be 8.2

 

Without the later EI coil all you get is a pointless ignition. The EI coil is designed to handle a full 12 volts and works without the ballast resistor. The points coil would over heat and the points burn out in 50 miles without it.

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Work has begun.

 

Wheels on with temp lug nuts, need to order step shanks.

 

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Manifold on,

 

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Started installing the GM HEI with an Nissaan electronic distributor.

 

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Found first problem, hinges for hood are busted. bummer...

 

 

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Looking to trade out clock for Tachometer, ya I know that is going to cost me...well, if you need to make a few dollars and you have a tach, let me know.

 

 

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Wanted to show off latest Goodwill find $25

 

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A whole lot more work to follow.

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  • 4 weeks later...

Mike, it does have the flat top pistons.

What does that do for it? I understand it will raise the compression. Is there anything special about that setup? W53 head with flat top pistons.

 

It also has an oddity of dual dipsticks, they are both oil and go down into the pan. Anyone know why?

 

Just finished up with the EI with a GM HEI module. I bought a 1980 720 Coil (new).

 

I also scored a set of SK Sanyo racing carbs for it. I understand they are the evolution of the solex pph40's. I guess if I can find the SK topper they can be ran with a blow through turbo system (so I read).

 

I am also custom building a tach for it using the Factory 620 clock. I found a Tachometer Face that is very similar to the stock 620 tach.

 

Having fun with this build.

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