Well, I have an update for you guys.
I posted a couple of times about this 82 truck I bought and you guys were
helpful. You can read them Here and Here.

Long story short, I decided to stuff a 289 I traded a welder for from a family
member. Its was originally a 66 mustang 289 2V auto engine. It was rebuild
once some time ago and was pulled to stuff in a 351W. I sent it to a local
machine shop for a few upgrades.

Anyway, I had this 289 built for a 57 ****** Jeep pickup. But all the issues I
had with the Supercabs 351W and emissions issues, I decided to put the 289
in the 82 truck.

I removed the EEC III module from under the seat, traced the attached
harness to the engine bay and pulled it out. I only had to remove a couple of
ground wires, a lead to the AC pressure switch, and a lead to the hot side of
the solenoid. I removed the duraspark box and distributor and related wiring
also.

The 289 is basicly a stock shortblock. The heads were fitted with screw in
rocker studs, pushrod guides, larger valves, etc. Intake and exhaust ports
were gasket matched, and polished up a bit (not too much) and the valves
unshrouded. I installed a Performer 600 cfm carb, and Performer intake. MSD
pro billet distributor with a Blaster II coil, Summit Damper, and a "stage 3"
cam from Engine Pro.
Cam specs are:
Hyd stage 3
DUR @ .050” Int/Exh 214/224
ADV duration Int/Exh 288/300
Valve lift Int/Exh .472/.496
Lobe Sep Int/Exh 108/116
Power Range 2000-4500 RPM
Idle Fair
COMMENT: GOOD LOW AND MID RANGE TORQUE AND PULLING POWER.

Im having and issue timing this motor. It seems to want way more initial than I am used to using. I first set it with about 14 deg based on the fact that most "RV" cams are already ground with anout 4 deg in the cam already. Im a stage over so I tried about 20 degrees and the truck still suffers from lousey off idle and and a faint popping under acceleration.

Any ideas?

 

Sounds like a cool combo. You have put a lot of detail into that motor.

Was the cam degreed? If so the advance built into the cam was taken out, meaning the cam itself has been 'ground' with advance built into it's valve actuation, not spark advance.

Initial timing is generally '10'. Timing advance can help you get your full advance timing to where the motor likes it. 'Generally' stock Ford motors like a lot of timing, but you would have to Dyno it or race it to find it's ideal full advance timing. But to much initial timing could give you part throttle ping or detonation.

Set the initial at 10', check it's timing at full advance and drive it some and see how it performs.

 

When I started setting up the engine for the Wilys, I was in an all fire hurry
to slap all of the covers and accesories on it. I did not degree the cam and
assumed the builder set the timing components correctly. I then installed the
whole thing in the ****** so I could fab up the engine perches and trans
crossmember. The engine sat like that for a few months before I decided to
put in in the Ford.
I installed a summit harmonic damper and used the pointer from the 351w.
I had to do that because the 289 pointer is cast into the cover and I
replaced it with a dorman aftermarket. I also utilized a drivers side water
pump outlet.
So, using a piston stop, I found #1 TDC and marked my damper. I then took
some tape and tansfered the marks from the balancer and relocated the
tape to my 0 degree mark(TDC). The rotor points really close to #1 cap lug.
I set the initial to 10 degrees and have yet to do anything with the curve in
the distributor. I am using ported vacuum to the distributor.

With this setup, I was getting the issues I decribed above, as well as low
vacuum about 8". By turning the distributor and advancing the timing to
about 20 degrees, the vacuum goes up toabout 12" and it runs better but
still no real power.

I'm at a loss. Maybe the valves are too tight?

 

Looks like you know what you are doing setting the timing, and even though you have a bad combo of parts(different harmonic balancer and pointer) none of that matters if you have used the piston stop and have reset everything and made a new TDC mark.(I am mentioning this which you already know for viewers of this thread that may not know).

So I will ask a rookie question, hope it doesn't ruffle your feathers, but you have been disconnecting the vacuum advance while setting the timing correct? My next question is a little more involved, are you running vacuum advance at all? If you are, how much does it add(if it's the stock unit, it adds a lot) and have you tried a road test with the vacuum advance disconnected? I have experimented with this before, and found the factory vacuum advance adds way too much on a modified engine with the initial set way up. The 302 I built for my 80 had this problem, and it ran best with about 14-16 degrees initial and no vacuum advance hooked up. I later had an adjustable vacuum advance installed, and kept adjusting it as much as I could till it started giving me running problems like yours. I ran it a long time though, with no vacuum advance at all, and it had a lot of power, and decent fuel mileage.

Unrelated question; What did you do about the rear sump oil pan situation with the 289?

2nd question;I suppose the Summit balancer you bought used 4 bolts to the hold the crank pulley on? The early engines used only 3 bolts to hold the pulley on, and I am wondering how many pulley alignment problems that causes. You may have avoided that whole situation by re-calibrating and using the newer style balancer.

And a final comment; Your engine may always have a little problem off-idle, since in the cam specs it's starts out a 2000 rpm. That's a problem sometimes with heavy trucks and small engines that like to wind out.

 

I have a similar setup, but with a 302 rotating assembly in a 1965 (1966 assembly date) 289 block. With a 600 CFM Holley, Edelbrock Performer RPM intake, 1.6 Ratio Erson stud mounted roller rockers, the crappy 1982 heads, an unknown cam, and a Duraspark II setup. It pulls 9" of vacuum in gear and 14" in park.

With 10 degrees of initial timing it runs quite rough, turning the distributor makes it run smoother, even beyond 20 degrees. I found that putting the Distributor advance to full manifold vacuum really smoothed it and and improved the cold running performance before the engine got to operating temp. It idles pretty darn good with 10 degrees initial + 28 degrees of vacuum advance, but then I tried 17 initial and full throttle performance went up, and light throttle performance went down and I backed it off to 14 intial but it is just "okay" there. I figure the vacuum advance is adding way too much advance. That's funny because Franklin2 just mentioned basically the same thing above.

 

Do you have any idea what the compression ratio is? The older heads had small combustion chambers and with the additional machining could bring it up more than expected. Maybe do a compression test if it is not known, wouldn't hurt anyway. And it might not hurt to add some gas additive and run some fresh higher octane gas.

 

You have a terrible engine build for a truck knocking on 6000 lbs. You don't ahve enough displacement and that cam is hurting you bad. It's more duration than you want on a truck and it's on a tighter LSA. It will be mushy with little power down low. Nothing you can do to fix that aside from change the cam.

The backfiring... What does your timing curve look like? Could be too much initial. Shoot for 14*-16* initial with 36*-38* total around 3000 RPM. Keep vacuum advance mild to moderate. Backfiring could also be from a lean condition. Check accelerator pump/discharge/profile and also jetting. Not up on Edelbrock or AFB style carbs so you're on your own there. I'd recommend a Holley 4150 650 CFM-ish but an Edelbrock can work fine if tuned properly.

What gears does the truck have? Without gearing to let that engine build RPM quick it may also encourage backfiring and odd running characteristics from bogging. You should have at least 4.10 gears in that truck if not 4.56 of higher. That tiny engine with relatively large cam for a heavy truck will need a lot of mechanical advantage to get that heavy pig rolling and build RPM like it wants to.

Personally given what you have I'd save the 289 for something else and freshen up the 351 that was originally in the truck with a few tweaks for torque. Heck, a 351 is underpowered for these trucks but they'll be fine if you don't tow.

 

Another update:

I finally realized after a few days of driving the truck to and from work
(about 2 miles each way), there was just something not right.
The truck run too cool according to the dash gauge, but was puking coolant
out of the overflow and the upper radiator hose was getting rock hard.
I began to suspect the failure of a head gasket, cracked head, or cracked
cylinder wall. So I did some internet research.

A test of the coolant verified presence of exhaust gasses and a visual
inspection of the front outer corners of the head to block revealed
this tab was not on the front of the drivers side head.
The drivers side head gasket was installed backawards
and was only cooling the front part of the head. The over heating rear
section of the gasket was actually cylinder pressure into the coolant passage.

Once I resolved the financial end of the deal with the machine shop, I set
out to get this sorted out and runnning right.

I pulled both heads, resurfaced both heads (luckily no warpage was found,
only .002" was removed to clean the surface again) and while I had the
heads off, I delved into the timing issue.
Rotating the engine to #1 TDC, I realized my issue instantly.

I am using a Summit performance balancer that has three sets of timing marks.
The instructions do not tell you what marks to use with what pointers and
so forth. The generic statment is to see which set of marks line up with your
pointer, yada, yada, yada.

This is the pointer I pulled from the 351W. My natural instinct was to utilize
the very top most portion as the indicator and heres where the issue lies.
I didn't realize that SBF's utilized a 10 AND an 11 o'clock position
(as well as the driverside cast pointer and a couple of other van types).

Anyway, I was using the 11 o'clock type indication and until i pulled the
head, didn't realize it. If you look at the pointer, the probe hole has a flat
portion just above it. Thats where the 10 o'clock position is!!!!!
So I verified TDC with that flat of the pointer and started reassembly of the
engine.

I reinstalled the heads with Felpro Permatorque gaskets, ARP head bolts,
Edelbrock intake gaskets and properly torqued everything.
I re-stabbed the MSD distributor and had a beer and went to bed.

Sunday morning I went out and fired up the truck. WOW! What a difference.
I had to swap advance springs in the distributor to get about 36 degrees
total advance at about 3000-3100 rpm.

This 289 supprised the hell out of me. It pulls real good from idle thru about
70 mph under part throttle and is real responsive.

As mentioned above, He is correct. This engine bogs down under full throttle
from a dead stop. But, I have 3.89 gears in the rear of the truck and didn't
buy it to race. The engine was built for a 57 ****** Pickup that weighs 3100
lbs and has a final drive in 1st gear of 12.18 in hi/1st and 29.59 in low/1st.

Here's a chart of my speeds at a given rpm

This lists the RPMs my engine will be turning while driving at a given speed in MPH.
This chart lists the road speed I will be going while the engine is at a given
RPM. Road speed is calculated based on the transfer case being in high
range.
I think this is right in line for what I'm looking for in an all around fun machine.