All Small Six 68 Bronco 170 tuning

[Bronco68]

"...Any reason for concern with these numbers?..."
"No"
as the other parameter: "all w/in 10% of each other" is met. These ol rigs can run well on very low compression & U R not even close yet.
I'd skip the DUI & go w/the DSII. Poor reports on it & even the racers use the DS (some w/the hei 4 pin steada da 'blue strain relief' ford box).

Any opinion on the pertronix ignitor looking at that as a option too?

 

[Bronco68]

Alright I was finally able to get a dwell meter and tested it out with my points gap set at .027. The reading I got was 20 degrees. I was able to get the dwell up to 37 using a .018 gap. Is this OK or is this indicating I have a problem?

 

[chad]

initial + mechanical = totals of 37, 38* is what we recommend. Take a look around w/Search function. Use "the Handbook"

The Ford Falcon SIX Cylinder PERFORMANCE HANDBOOK | Vintage Inlines

The Ford Falcon SIX Cylinder Performance Handbook has 107 pages of History, Facts, and Information to help you get more power out of your small Ford SIX. This engine was used in Falcons, Mustangs, Fairlaines, and Comets in the 60’s. It was the FoMoCo workhorse in Mavericks, Granadas, and...

www.vintageinlines.com

while waiting delivery the above tech archive:

Classic Inlines

for free. Vacuum gauge tuning recommended as well. Last go onto carb tune...
If U have a '68 U R above 2 'cut off' yrs ('64 & 7) for the last 2 sentences of my above recommendation.(carb upgrade / I'd skip the DUI & go w/the DSII. Poor reports on it & even the racers use the DS (some w/the hei 4 pin steada da 'blue strain relief' ford box). Skip the petronix instead. C above 2 literature cites.

 

[bubba22349]

Alright I was finally able to get a dwell meter and tested it out with my points gap set at .027. The reading I got was 20 degrees. I was able to get the dwell up to 37 using a .018 gap. Is this OK or is this indicating I have a problem?

Yes if you have 37 degrees dwell that is great the dwell setting is the most accurate way and gives the best engine performance, there is nothing wrong in needing to tighten up the gap to get the correct dwell reading. The .027 gap setting is just a basic setting to get the engine running you will always find that as the points get set tighter than the dwell degrees also goes up. Next time when you change points you can start at the .018 gap and then check the dwell in your Distribitor this should be real close to being right.

 

[Bronco68]

Yes if you have 37 degrees dwell that is great the dwell setting is the most accurate way and gives the best engine performance, there is nothing wrong in needing to tighten up the gap to get the correct dwell reading. The .027 gap setting is just a basic setting to get the engine running you will always find that as the points get set tighter than the dwell degrees also goes up. Next time when you change points you can start at the .018 gap and then check the dwell in your Distribitor this should be real close to being right.

Thank goodness! At this point it's idling great at about 700 rpms. Initial timing is set to 8 btc and vacuum is running at about 19.5 psi. Highest I could get the vaccum was 20psi while adjusting the mixture. Idling and high rpms seem perfect but it's a little rough between 1000-1200. Can this be smoothed out adjusting the vacuum advance canister?

 

[bubba22349]

One other thing to remember is that the point dwell needs to be set right before you even try setting the base timing is set because the dwell will change the base timing some. I alway use this order

1968 Ford Bronco 170 Six Stock Tune Up Specs

1. Set the spark plug gap to .034
2. If your 170 has a Solid Lifter Cam set the valve lash .018 H with the engine warmed up good.
3. Set the points dwell to 37 degrees.
4. Set your Base Timing. The stock spec. Is 6 Degrees - (8 is good to) Degrees before TDC.
5. Set the Carb's Mixture Screw to the "Lean Best Idle". To do this Set the Idle Mixture screw using your Tach / Dwell Meter to its highest RPM, then turn the mixture screw inward 1/4 turn to lean it out.
6. Set the Carb's Curb Idle to spec. this is 700 RPM.

Try doing it like that and see if the engine's roughness goes away. Best of luck

 

[DrDave]

I have a 68 bronco with a 170 that has been sitting for several years. It wasn't running at first so I just did so basic cleaning up of the plugs/points. It fired right up but was occasionally missing and dumping black smoke. So I decided to replace all the plugs, wires, distributor( original was a dual vacuum advance that was plugged off I replaced it with a single vacuum distributor hooked up to ported vac), and sonic cleaned/rebuilt the carter yf carburetor. All the smoking and missing issues are resolved and it fires up idles like a champ but as soon as I start to give it gas it stumbles and almost dies. Is this a timing issue with the vaccum advance(Initial timing set at 6 degrees) or a gas pump problem (inline filter only getting about a 1/4 of the way full)? I threw a picture of the carb and distributor to see if anyone can confirm that they are compatible I've read that some carb distributor combos will not work if mismatched.

I had been dealing with a similar problem except my stumbling-stuttering started around 1k rpms. Turned out to be a failed vacuum advance. With new one, engine revs right up with WAY more power. Huge difference!

 

[chad]

go w/a full tune, correct order. Dont throw parts, time, money at a problem.
Know it's right from the start as U go thru & U will C what's in need. THEN
go onto carb.