1972 Maverick Sprint

[Maverick]

I took the Sprint to a church meeting last Tuesday evening. On the way home, on an unlit country 2-lane road THE LIGHTS WENT OUT!! Car behind me and no place to get off the road. I slowed it down looking for a place and the guy started tail gating me. Don't know if he was trying to help or ticked off 'cause I was out there holding him up with no lights. Didn't matter -- he was putting enough light on the road ahead of me that I could keep going. Fortunately, I didn't pass any cars in the opposite direction. I was worried someone wouldn't see me and make a left turn in front of me. (Thinking of the WXO Camaro incident.) Before I could find a place to pull off, lights came back on and stayed on till I got gome. I assume the circuit breaker in the light switch tripped and reset. Installed a new Motorcraft switch today.

Thursday, WXO and I are taking the Sprint to RPM just South of Raleigh for a dyno tune. I set the initial timing to 15 degrees BTDC and getting total advance of about 40 degrees with NO detonation on 87 octane. Will be interesting to see where the guy sets it and what parts he puts in the Holley. It seems to want a lot of advance.

I also changed the vacuum advance source from ported to manifold vacuum. Hesitation is better but still unacceptable. I can now take it gently off idle without a stumble. Hope things are a LOT better on Friday.

It runs pretty good once it recovers from the stumble but doesn't feel as strong as I had hoped. Think I'm gonna need more motor.

[markss327]

It should prove interesting, the deltas between the current carb\ignition settings, and the final settings, after the tune.
Like primary and secondary jetting, squirter nozzles and cams, and of coarse, initial and total timing. All that good stuff, that will drive ya crazy, trying to get that perfect combo.

I remember... the Nova liked lots of advance too.

[MostMint]

Hesitation is better but still unacceptable. I can now take it gently off idle without a stumble.

I am going to guess that you need more fuel from your accelerator pump. This can be achieved by changing the plastic cam to a more aggressive profile, and by increasing the shooter nozzle diameter. the Holley book has the cam profiles - blue is an aggressive one if I recall correctly.

Of course this assumes that the acc pump does not have any slop in it and the acc pump itself is not malfunctioning in some way.

All you guys taking cars to the tuner. To me the tuning is the "easy" part. If I start a second career I know what it is going to be.

[Maverick]

Yep, to the tuner. I like doing stuff myself too but I've never tried to set up a Holley or HEI advance curve. He can read the air/fuel mixture and spark advance on the dyno from idle to 5K+ RPM and WOT.

I think the hesitation could be accelerator pump settings or might be advance curve. Low vacuum gets a quick and significant spark retard. And I think the carb is a little oversized for my setup. Might need bigger jets. Power valve might be OK but how to be sure its the best one? Too many variables for a novice.

And, I want it dynoed anyway. I read a little about converter stall and understand now why you guys were suggesting higher stall. I had a basic misunderstanding of converter stall. Torque curve will help me select a converter (someday).

Its expensive but I expect a much better result than if I tried to do it myself. Gotta optimize what I got before I decide I need more motor.

[Fred32v]

Changing the converter should have been done already, that tune will help,
but changing the convert will change the personality of that Maverick like you can't imagine.
A bigger motor is nice,but not necessary, you need to get to what that 302 really has to offer.
It's not that big a job since you have WXO there, I would encourage you not to wait.


An aftermarket converter isn't necessary, if Ford is like GM,
there is probably a stock higher stall converter in some Ford truck.
GMJohnny and BP both upgraded to much more lose stock converters
at a fraction of the cost of aftermarket.
They might be able to say more about that.

[Maverick]

Changing the converter should have been done already

Yeah, I know, ... now. Like I said, I had a misconception about converter stall. May be repeating myself, but I assumed converter stall was like airplane wing stall -- the MINIMUM speed at which it can be effective rather than the MAXIMUM RPM with drive wheels locked. Although you guys told me to go higher stall it seemed like a bad idea given my misconception and the way I'll use it. 99% of my driving will be puttin' around town with an occasional romp.

I'll think about it some more after I see the torque curve. We've already pulled the trans out once to replace the flex plate with the wrong counterweights. Not that big of a deal. We managed to get it out and back in without it fallling on anyone's head.

BTW, I found the bill for that flexplate. Shows the same part number on the invoice as stamped on the flexplate. Invoice says its a 50 oz imbalance. No way.

[MostMint]

And I think the carb is a little oversized for my setup.

Now I am even more sure that you need a bigger or faster accelerator pump shot. The idea of a "too big" carb is a misnomer in my opinion. The problem here is that when you crack the throttle, the air speed into the engine slows. To compensate you put in more gas to offset the disturbance as you transition from idle circuit to the main venturis. If the carb is smaller the velocity drops less and you can get by with a smaller shot. This is how the manufacturer sets up the carb. If you have a larger barrel the velocity will drop more and you need a bigger shot. The inexperienced put that carb on and say "oh the carb is too big and the engine can't take the gas", when exactly the opposite its true. The thing needs more gas to get through the transition.

As far as power valves, the rule of thumb I recall is they should be at about half of the manifold vacuum. If you are getting 16" of vacuum at idle, your power valve should be an 80. If you can't get one I would round down to a 75. All the power valve does is help with the transition of fuel delivery at part throttle to full throttle conditions. If you have mechanical secondaries you can go without a power valve on the secondaries - but you will have to jet up 6-8 sizes to compensate.

As far a O2 sensors - we used to read the plugs to tell if the metering was correct, and used the 1/4 mile instead of a dyno. I guess those days are going the way of the pay phone. Too bad you don't live nearby as we could make a Saturday out of dialing that car in.

I'm sure the tuner will get you a good result and I am interested to see how it goes.

All the amazing work you have done with this car is way out of my league! No way I would have the patience for all that. It's just peculiar to me that when you are finally getting into my league (with tuning and performance) that you are farming it out.

Any update on the seats? Did I miss that?

[Maverick]

One of the issues on carb size is the vacuum secondaries. Will be very interested to see if the secondaries open completely. I suppose there are adjustments/replacments for that too.

It would be fun to do all the tuning but not something I'll try alone starting with all these non-native components. I'd love to follow along with someone who knows about it. If we were closer I'd sure take you up on it. Maybe once its set up I'd take a crack at tuning for any changes.

I removed the covers from the Camaro buckets 3-4 weeks ago and shipped them up to the upholsterer in RI to use as patterns. He already had patterns for the rear bench. He was busy with a couple of other jobs and didn't get them measured for a couple of weeks. Recently got the word that I need 2.5 yds of the blue material. First couple of pictures I got from the supply house weren't the right stuff so when they THOUGHT they had the right stuff I had them send me a sample to verify. Its good and I just ordered the material this morning to be shipped to the upholsterer. Haven't got a schecule from him yet. I'll give him a week or so and then check with him. Right now I'm driving it with the bench seat.

Haven't installed the carpet yet because I only want to make holes for the bucket seat mounts.

Went over the car one more time by hand with rubbing compound and now its ready for some wax. May post again when wax is done if the shine improves noticably.

[MostMint]

Vacuum secondaries are also quite adjustable. If the spring is too firm it will not open all the way - and the manufacturer provided spring is usually one of the firmer springs. I prefer mechanical secondaries as you get more flow at lower velocity if the secondaries are open all the way.

What is the bore and stroke on this engine, 4" by 3"? Shorter stroke usually means more top end power. Everyone likes that feel of torque from the big cubes, but with the small displacement V8 you have to get the gearing right to get to the top end horsepower. Oh and it'll need to rev a little more - that's what it does best. The benefit of the higher stall converter is much more noticeable with engines that have less low end torque.

[Fred32v]

Boy Jim, the Maverick really looks great. Sweet pictures.
I like that the licence plates match the car's color. Clever plate number.

[Maverick]

Boy Jim, the Maverick really looks great. Sweet pictures.
I like that the licence plates match the car's color. Clever plate number.

Thanks, Fred.

In NC for vehicles at least 35 years old you can run a plate from the year of manufacture. Just have to produce the registered plate on demand.

Picked up that unused 1972 plate at a Raleigh car show/flea market last year. That year, like this year, the plates just happen to be Grabber Blue/Wimbledon White. The "1963" number is going to confuse folks but there isn't a lot of selection with uncirculated plates.

When I registered it, I ordered a personalized plate, "BKETLIST". It was about my 6th or 8th choice for the message I wanted. Hope you get it. Most don't. I'm hoping it also comes in blue/white.

So, I'll have a couple of interesting plates. I'll be able to change plates like I change socks.

[Fred32v]

Got it.

[GMJohnny]

Back to Fred32v's comment about torque converters. I agree with him on the "cheap" manufacuturer
truck version. On my 96 Roadmaster wagon, I used an S-10 converter and it was way looser than the
stock wagon converter. The Vette's converter is from a pick up truck also. Both were just a different
version with higher stall that went into the trans in a truck application. I would be surprised if Ford
didn't do the same. I was able to find out both of my "secrets" from the internet and guys who had
worked out the details before me. In both situations, I was able to pay way less than a hole-shot or
some other type of converter that the car really didn't need. The converter for the Vette cost less than
1/2 of a "race" converter and was a manufacturer approved converter. Even the guys who did the install
felt very comfortable putting it in the car. Just food for thought........ Good Luck!!

GM

[Maverick]

Good thoughts. Thanks.

[Basement Paul]

I really love the way it turned out! Maybe someday I'll have the time to put into making a car look that good. I think it would be fun learning and doing.

I love that vintage car too. Just barely past the muscle car prime. IMO, there's a lot of really cool cars that came after '71.

-BP