Hi guys,

I've got a 78 supercab 4x4. Got a 428, presently with a Edelbrock 650 carb, which I am told isn't nearly big enough, though it's been jetted as far as it will go. I plan to replace it with a Holley 770 TA (unless someone's got a better idea?) and I'm also told I really should go with an electronic ignition. (The last one was an old Mallory/Unilite POS. Ignighter would fry, and I was stuck waiting for an expensive part which apparently came from Egypt by dog-sled via Norway) Currently running a standard points system, which I can fix on the side of the road if I need to.

Anyway... any suggestions on ignition system, or carb?

I use the truck for hauling camper,and horsetrailer as fast as possible. I go off road as well. I want dependable, fast and easy to fix.

Thanx

 

I have an MSD pro-billet Dizzy with MSD Blaster 2 coil and MSD 6AL box. I love it. Pretty close to just being a plug and play. Just becareful which dizzy you order if you go the pro-billet route. One requires an MSD ignition box the other is compatable with stock ignition. By the way my pro-Billet is mechanical advance which is why it's almost plug and play. you can get it with vacum advance if you want. For carbs I was going to get the 770 TA also but was advised against it by two different shops. One shop just wanted to sell me a 750 double pumper. The other shop said he has yet to tune a TA that didn't have problems. He blamed it on poor craftsmanship. Please note the second guy does NOT sell parts, only tunes them. I went with a 3310 (750 vacum secondaries, single pump) Good luck with your decision

 

What is the max rev you are turning with this engine? That, above all else should determine what size carb you should run.

 

Good question that I can't answer. I can't find my notes. I took it to a shop after having massive problems with timing... turns out the dist. was for a car, and it was advancing way too much. Dist. was rebuilt and recalibrated. Problem solved. Mechanic (one of those rare guys who does it cuz he loves it (he races too)) suggested the 770 based on all his data on the motor. He said it would run much better with electronic ignition and the 770 carb. He didn't try to sell me either....

 

I would suggest a stock DuraSpark that has been gone through.

Get it recurved for your application and you should be good to go. The MSD unit has the same pickup coil as the Duraspark.

I was running the MSD unit but traded it in on a Duraspark so I could get the vacuum pot on it.

I am also running the MSD 6A box with the Duraspark.

Tmod

 

I would definitely go with the Holley 770 Steet Avenger (not the Truck Avenger). I have been told countless times that the TA is a very poor carb when compared to the SA. I have the 770 Street Avenger on my 390 and I absolutely love it. My gas mileage improved to.

 

The TA is a great carb if you can get it tuned right. Just remember that the SA is not an off-road carb. If you plan to tackle anything above a 14 degree slope, it will stall. My machinists truck had a SA on it and the poor thing couldn't handle the slopes to save its life, but never has a problem on the street.

 

Go with the Duraspark, replacement parts are available at any parts store. Use a MOTORCRAFT Duraspark module. Mount the module on the inner fender with 1/4" spacers to allow cooling air under the module. I use 5/16" hex nuts for spacers.

 

I know I aint the brightest bulb in the room, but how the hello do ya tell when ya got a dist. for a car shoved in your truck motor?

an onther thing, How do ya tell when ya got a truck 428??

Shoot, I'll bet if ya aint racing that ol 428 a 600 cfm would run it just fine.

just wondering

John

 

John,

Car dist.: It's like this.... you break down on the side of the road with a horse trailer stuffed with horses, and a 200 lb dog, and the bed full of camping gear. (Best if it's also hot, and you've got your step-mom, and daughter along) Being a woman who can turn a wrench means that while I'm relatively capable, I'm not the best at figuring out what the hello is actually wrong. Cell phone my Dad, who IS good at such. He determines it's the fricken module, AGAIN. Off to the nearest NAPA, where I get the usual argument that I can't have a 428 in my truck *sigh* Get 390 dist. Put it in, adjust a few things, and it's off to the races.

After many adjustments by myself and my husband, we can't get the timing right. Call many shops, looking for an "old school" mechanic. Locate Rick (picture god-like older guy, permanent grease under nails) He's wonderful. He also doesn't mind all my questions, nor the fact that I know just enough to get myself in trouble.

In answer to your first question: A 390 car dist had lighter weights in it.... the higher vroom-vroom (note use of clever technical term) of my beefy truck creates alot of centrifical force, which caused the advance to go way past where it should. (64 instead of 32-34 (if I'm remembering correctly)) Heavier weights and recalibration fixed this.

Your second question: I was told the truck had a 428. All the paperwork on it(from previous owner who had the motor installed) said it had a 428. I looked up all the numbers on the block, heads, etc, and they all say 428. This truck is not stock, obviously. And it's been an endless sourch of argument at every parts store I've ever walked into. Along the lines of "Lady, you can't have a 428. Fords don't come that way" Usually, I end up rattling off a buncha numbers, then eventually drag the clerk (and half the customers) out to look under the hood of "The Green Bean", get my parts, fend off marriage proposals and go home.

I hope this helps. Sorry I'm so long winded, I think I OD'd on coffee! *grin*

 

natira121,

There is a slot in the centrifigual advance plate in the bottom of the distributor that has different width slots depending on which vehicle the distributor was intended for.

That slot is the one that controls how much total mechanical advance you will get. The springs control how fast you will get it.

So distributors that were meant for another combination may have a different total mechanical advance.

Tmod

 

First off lighter weights bring in the advance slower, not faster and heavier weights advance faster. Conversely heavy springs retard timing advance and light springs bring in the timing quicker(at lower RPMs). The advance can not go past whatever the dist. is set for. Usually 10 to 18 degrees in the dist.(I've seen one 8 degree dist in my life) or 20 to 36 degrees at the crank. It is a mechanic impossibility for it to advance past the stop unless omething breaks. The only thing in the system that can kick timing up to the numbers you are talking about is vacuum advance and that can't do it with the engine under any kind of load, again a physical impossibility. The heavy weight fix would have make the timing more race car like(you know higher vroom-vroom).

 

Okay, *sheepish grin* Like I said way up there somewhere.. I lost my notes. I appreciate the education, and I'll add all this stuff to my ever-growing notebook. I will also hang out here more often, so I can ask itelligent questions, especially since I've decided not to sell my truck, but to continue my work.

 

I like the MSD 6AL...You can use it wth your existing dist...Seems you already spent the money to have it properly recurved...The MSD will give considerably hotter spark and longer duration, and you can limit you rpm, for um...mistakes in judgment.....With the msd, no current is put thru the points, so they never burn, or pit...Eventually the rubbing block wears out, but I havent replaced mine in 7 years..

As far a a carb...the 600 you have, will run fine if its properly jetted, but will be way down on power at wide open throttle..Some like holleys, but i prefer the Edelbrocks, As I find them much easire to tune...D44HD