Sluggish performance and Air filter spacer

[72bumbee]

So after posting about the new drop in MSD distributor, I came to the realization that I would need to raise the air filter up off the distributor and the carb throat … I bought a set of spacers from O-Reilly's for 11 bucks and not a single one of them fit around the carburetor. As the largest diameter I've found is 5 1/8 and my filter base is 5 1/2.

Another odd thing is that now that I have the engine timed, it becomes sluggish and doesn't want to accelerate. Its like its either getting too much fuel or the choke is still closed.

Any advice would be welcomed.

[colnago]

First, I'm really surprised the spacers don't fit. I thought that was pretty universal. I suppose the next step is Amazon or eBay.

On the sluggishness, I was always told to work on ignition before you work on carb. I don't remember, do you have a timing light and vacuum gauge? My old engine liked 8 degrees initial, but my rebuilt likes 14 degrees initial. Have you mapped your timing curve, so you know it advances as expected? What is your idle RPM?

Do you have a 12V coil? If so, is it getting the full 12 volts? If not, you might have to bypass the ballast resistor, or install a relay (My project for tomorrow). If it is getting 12V, do you need to recap your plugs? Have you done a compression test? My last engine read ~120 on all but #1 (70) and 3 (35!). Very sluggish, but I ran it for five years that way.

I tend to buy my tools as needed, but you can probably borrow some from AutoZone. At a minimum, I recommend a vacuum gauge, timing light, and RPM gauge/tach. My suspicion is that the MSD is not adjusted properly, or it's not advancing properly.

Joseph

On edit, I just checked my parts bin. Looks like I picked up Mr Gasket 6411G spacers from O'reilly, and they do measure 5-1/8". If you're handy, you could cut the riser in one place, fit it to the carb, then patch the gap. No, this would not be a permanent "fix," but you could use it to see if everything else lined up properly, then find a real replacement on Amazon or eBay.

[72bumbee]

Thanks for all the solid advice... I know nothing about timing curve or advance degrees... etc... my experience with tuning is elementary at best.
I have a timing light... used it to set the current timing. Have no idea what the dial on the back is used for, but I just left it at zero.
No vacuum gauge... was looking at them and believe at NAPA it was about 50 bucks.
Another thing I need to confess is that whoever had the carb off last time, had the choke stop screw ran all the way in, so the auto choke was never on, and even the choke heater line was completely out of the bracket so I put it all back the way it was five years ago before the crate engine was dropped in.
Also, I have a tachometer wire unused coming off the new distributor but have it just hanging. Could this be used in fine tuning or would I need some tool for this also?

[colnago]

The dial on the back of the timing light is to read the actual timing with the timing pointer at zero on the harmonic balancer. For example, if the dial was pointing to 13 when the zero mark was on the pointer, your timing would be advanced by 13 degrees BTDC. You can use a non-dial timing light, and some people don't like dial timing lights; it just makes some things easier.

I just went to the Harbor Freight site. They have a vacuum gauge for $14. It's called a fuel pump and vacuum tester (item 62637). I don't know what NAPA had for $50, because the gauge/tester should cost less than $20 wherever you go.

As far as checking your curve, you get the engine Rims up to 500, 1000, 1500, 2000, 2500, 3000, 3500, and 4000. At each RPM, you check the timing advance. Write them down, then plot them. This is your timing curve. Everyone has different requirements, so different curves, but in general, it's flat to 1000, then climbs until 3000-ish, then remains flat-ish (like I said, they're all different). At 3000 - 4000, you should be at max advance (somewhere between 32 and 38 degrees BTDC). This is where the dial timing light is helpful.

You can also check your plugs. Get up to speed, then turn off the engine, and coast to a stop. Pull a plug, and read it. Black soot is rich, white or light gray is lean.

You can check for vacuum leaks by getting the engine up to temp, then pop the hood, and spray brake cleaner around the carb, and any tubing that runs to the carb. Don't spray it in the carb intake (it won't hurt anything, but it affects the test). If the idle changes at all, you found a vacuum leak.

By the way, for all your testing, and to set up your initial timing, disconnect the vacuum can on the dizzy, and make sure the line to the carb is plugged. Use a golf tee or pencil pushed into the rubber line.

Joseph

[DuckRyder]

MSD distributors come from the factory with a very slow advance curve, did it come with some bushings and springs? Does it have 2 heavy silver springs in it?

So your timing light has a dial back? Cause it will come in handy if so...

[72bumbee]

I feel like a toddler in an advanced quantum physics course.......
So I’m guessing I’ll need a tool for the timing curve, or a trained professional.
The distributor did come with a bag of stuff that included two small springs and a cute little hat that won’t fit on the dizzy cause the air filter is sitting on top.
How do I manage to get my wife to maintain all the various RPM’s in the timing curve?
I’d be happy just to have the beast run even half less crappy...
I know, I’m settling....
Again I’m emotionally overwhelmed by your actions and solid advice.

[DuckRyder]

It should have come with some bushings and springs and the instructions should show what the advance curve for each is.

IIRC it would have come with the two heavy silver springs which all the timing isn’t in until 4000 rpm. On a stock truck FE detonation shouldn’t be a problem, so frankly I’d probably just put the lightest springs in it and the bushings that give the most advance. You also probably need more initial advance. It shouldn’t take more than normal hand tools to change the curve.

Once you’ve selected the bushings and springs, in my opinion and for this application you need only concern yourself with the total timing. (and initial as a result of total)

Disconnect the vac advance and plug the line. Set your dial back timing light between 34/36. Have your helper raise the RPM above the all in RPM and then align the timing pointer with TDC by turning the distributor. Have your helper return the engine to idle. Turn the dial on your timing light slowly back toward 0 and stop when the timing pointer and TDC mark align. Write this number down, it your new initial timing.

Recconect vac advance and test drive.

[tnlprt]

initial timing should be between 12-14 degrees

total timing with vacuum unplugged should be no more than 37 degrees

Total advance should be all in by 3000 RPM

[72bumbee]

I couldn’t remember to plug the vacuum line. I had everything attached.
Not meaning to sound too ignorant... why does it rev fine when I’m in park and is only sluggish when I’m driving down the road?
Also, I was under the impression that this dizzy was a drop in and go?
Workin now so she’s going to have to wait until next weekend unless I find someone who is a bit more familiar.
Thanks again guys I really do appreciate your help.

[DuckRyder]

Try just setting the initial up per Tunnel Port’s post. (with vac disconnected to vac advance)

As for the air cleaner, you can grab any 14” round air cleaner assembly at the local big box auto china mart, of get a “sorta” Hi Po air cleaner like this:

http://www.mustangsunlimited.com/Mustan ... ustang.axd

From one of the Mustang places. Obviously you don’t need a concours correct one...

I’ll try to dig into the instructions for this dizzy and have some advice for you later in the week...

[Ranchero50]

So the drop in dizzy isn't...

[colnago]

The MSD is a drop-in unit, but everyone has different requirements. The FE was used in both cars and trucks. Kind of like camshafts: different grinds for different purposes. That's where the different springs and bushings come in. They let you modify the advance curve.

For holding a steady RPM, I use one of those "squeeze clamps" from the hardware store. In my case, one end goes to the back of the block, and the other goes to the carb throttle linkage (this is on my Edelbrock carb). I use zip ties to hold it in place. Then I start the truck, read RPM and advance, then squeeze the clamp to my next RPM setting.

Here's a quick-n-dirty sequence to get you in the ballpark. This assumes you have a tach, though. Also, disconnect the line to the vacuum can, and plug the line.

1. Set the dial on the timing light to 12.
2. Start the truck, and turn the dizzy until the "zero" mark on the harmonic balancer is lined up with the pointer. This sets your initial timing to 12 degrees BTDC. Snug the dizzy clamp down.
3. Rev the engine to 3000 RPM. Turn the dial until the zero mark on the harmonic balancer is lined up with the pointer.
4. If the dial is greater than 37, use a bigger bushing on the dizzy to limit it to 37.
5. If the dial is less than 37, keep increasing the engine RPM. Keep adjusting the dial to keep the zero mark on the pointer.
6. As long as you keep adjusting the dial, keep increasing the RPM. When it stops increasing, note the advance and RPM. Hopefully, this happens around 3000 RPM, and your advance is 37.

Then, we go from there.

Joseph

[DuckRyder]

So the drop in dizzy isn't...

Well sort of.

In fairness they don’t really call it a “Drop In”, they call it “Ready to Run” which also isn’t exactly true. Really what they mean is that it has a module built in and doesn’t need a CD box.

I had one of these and returned it because your can’t use a standard cap on it, which really doesn’t make sense, considering the market. The Accel “Blueprint” wasn’t any better at the time.

[72bumbee]

so now the light comes on!!
thanks for breaking it down for me and making it something I can actually do all by myself!!
so I literally went to the mustang site and purchased the air filter that DuckRyder suggested. that will make my life easier just having that problem cured.
The timing will be easier for me to understand the way you broke it down colnago I'm really not a moron, just a slow learner until I see it in my mind.

Thanks again as always and will keep you posted as to my progress