I have a 74 w100 with 3.91 gears a 3spd manual and a single barrel /6. I got some rapidfire plugs that seemed to help power tremendously, and i always fill with 91 or 92 octane gas. It seems like i need to upgrade my ignition system somehow, the truck does not appreciate hills what so ever. My timing is at 12 BTDC, to far advanced? Dont know what else i can do besides maybe MSD. Im trying to find a 2 barrel for my intake cuz the holley i have is junk...any suggestions would be appreciated. Thanks

_________________
Drive it like its stolen, and be glad im not YOUR son...

All right, we'll take this one thing at a time. Rapidfire plugs yield no performance benefits beyond good standard plugs (search the board for the NGK part number). Any performance increase from this is most likely because your old ones were in terrible shape. Filling with premium should not be neccesary for a stock engine and will yield no performance benefits. I don't know what stock spec was on that, but 12* sounds like you've got it advanced a bit too far. Do you get any pinging going uphill? As far as the ignition system, the most important thing is to make sure all of your components are in good shape, including plug wires, cap and rotor. If you do want to upgrade, the most cost effective solution is probalby the HEI conversion, which has been discussed numerous times on the board, and can be found by searching. Find yourself a good two barrel carb /and manifold/. Using one of those corny adapter plates will keep you from realizing a lot of the perfomance benefits of a two barrel. Beyond that, I would consider going to an RV cam and shaving the head to get your compression up around 9:1 or so. Just by doing those upgrades you should get it on par with a fairly warm 318.

_________________
Used to own:
'82 Dodge D150
Erson 270 Cam, O/S valves, mild port work, ~9.5:1 compression

Currently fighting with an '85 VW Cabriolet

My other passion

Might want to get 'em outta there before you wind up with little globs of melted piston all over their firing ends (seen it!). Best plug for your '74 engine is NGK number ZFR5N, sometimes sold by stock number which is 3459. Remember, remove the metal ring washers from the plugs before you install them.
Probably hurting rather than helping your quest for more power, and CERTAINLY hurting your bank balance.
Meaning...what? Won't go up them, will go up but lots of pinging, something else? A distributor recurve would likely find you a fair bit of extra power and driveability while reducing ping, but it has to be done thoughtfully. You may also want to replace your early electronic ignition box with HEI with an MSD Blaster coil, see HEI upgrade instructions, install a NAPA Echlin long-tip rotor # MO-3000 with Standard-Bluestreak CH-410X cap and open up the gaps on those ZFR5N plugs to 0.045".
Possibly, probably, maybe not...need more info! There were a lot of different emission packages in '74 even on trucks. What's factory spec for your setup?
No, get a 2bbl intake, don't mess around trying to adapt a 2bbl to your existing 1bbl intake.

How many miles on this engine? You may want to check for timing chain stretch!

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

Let's get some information, before we just "recommend" everything he needs to do...


I would like to know:

1) The model of your carb, and the size of the jet in the carb (if the stock Holley 1945, or a Holley 1920? Got numbers?)

2) Set the engine to TDC, pull the distributor, and disassemble to the point you can tell us the "governor's" slot size by caliper measurement of the slot or the number off the stamp on the governor...




The other's would be correct in letting you know that you may be 'band-aiding' the situation by running lots of initial advance (with a possibly long governor and vacc. advance), running a 1974 carb (which was jetted lean at the factory for early emissions....which isn't good), having a heavy vehicle (that load on the engine isn't good)...then trying to knock the ping/rattle back with extra octane....


Get us some numbers so we can recommend a path to get you dialed in on (it would be nice to have these numbers too, before you slap the super six on because it will benefit from a better distributor curve than the usual 1973-1974 curve...)




If you have what I think you got under there...we then would work toward:

Better distributor curve, less EGR, better plugs, better carb jetting until you can score a super six...



-D.Idiot

Okay, the engine i have is a 66 model that came out of a dart. I spun a rod bearing in my old one so i did the swap. Im not sure if a 66 came with electronic ignition but it had it when i got it, it also came with a super six intake and carb but the exhaust manifold wasnt the bigger one. For ignition the plugs, cap and wires are new and i couldnt get the damn engine to ping no matter how much advance i run. I set it to 12 because thats where i seemed to get the most nuts out of it. The carb i have now i believe is the 1945. The idea behind higher octane gas wasnt by any means to band aid anything, i believe that higher octane gas yields better gas mileage. As far as the hills go, the truck just doesnt have any power, i can do about 75 top speed thats in 3rd gear turning about 3 grand. When i get on the hill i have to drive up everyday i can hold maybe 40 or 45. If i hold the pedal to the floor it floods it out and goes slower than if i find what i call the sweet spot, where it seems burn as much fuel as possible. Also i put a block off plate on my EGR. I work at National Auto Parts so getting parts isnt a problem, i just dont know as well as the rest of you whats best for the engine, being 18 years old, im just trying to find what works best.What 2 bbl carb do you all recommend and do any of you have something i can use laying around?

_________________
Drive it like its stolen, and be glad im not YOUR son...

Are you sure it is flooding? It sounds like it is running really lean to me. The "sweet spot" you are describing is where the carb is not running lean. I would check for vacuum leaks if I were you. I have seen cars with vacuum leaks that were dogs under acceleration but would fly at part throttle.

_________________
82 D150-225/727
02 Dakota-3.9/5 speed
87 GMC C7000-8.2 Detroit Diesel/5+2

I know i dont have any leaks, i did the propane deal around my vaccuum lines and found one, but blocked it off. Could it be the air fuel mixture? I set it where it ran smoothest at idle, should i set it at a certain rpm?

_________________
Drive it like its stolen, and be glad im not YOUR son...

The thing you set at idle is just idle mixture. The only way to change mixture for things part throttle and above is by changing the main metering jets.

_________________
69 valiant

What kind of carb is it? I assume a Holley 1920. Is it remanufactured, original, or what.

_________________
82 D150-225/727
02 Dakota-3.9/5 speed
87 GMC C7000-8.2 Detroit Diesel/5+2

Im sure its a 1945 that is original. Iv rebuilt it twice but dont know how to change the jets.

_________________
Drive it like its stolen, and be glad im not YOUR son...

A month ago I put a set of NGK ZFR5N in my 64 dart and noticed an IMMEDIATE increase in power when I floor it.

I also think that there MAY be a tiny increase in gas mileage (as long as I keep my foot out of it).

I will be doing this change to my 66 2 bbl cuda as soon I get it out from winter hiding.
That car should really haul butt after that change!

Wholly old thread batman.

Galactica - regarding extended reach plugs such as the zfr5n - it's the equivalent of advancing your timing so many degrees. That could explain your power increase and gas mileage. If you opened up the gap as suggested that could have done it too.