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Discussion Starter #1
I'm getting my 65 6 cylinder back on the road after many years of sitting. I've replaced lots of things - brakes, exhaust, gas tank, interior, rebuilt carb and now I'm legal and sorting through everything trying to get it dependable, safe and comfortable..

I'm driving it around any chance I get and although it goes and stops it just doesn't seem to have any power. I can get to about 60 mph with my T5z but can't use 5th because the engine has no power and will just lug along. I've had a 66 6 cylinder years ago and I remember it being a lot more pep.

A little background;
  • Re-manufactured 170ci engine with about 7k miles. Does not burn oil, and has no identified problems
  • Re-manufactured LOM distributor with the same 7k miles
  • Autolite 1100 w/SCV, 200 miles, professionally rebuilt by recommended vender I've used in the past.
  • Tuned up 200 miles ago using timing light and dwell tach to specs in the Shop Manual.V
  • Engine starts easy and runs pretty smoothly
  • Spark plugs were just pulled and read normally, light grey/tan deposits.
They say the stock 6 cylinder configuration should be good for modern highway speeds, that's all that I want. I've heard that a tune up can be done using a vacuum gage to adjust timing for a maximum reading. I have a vacuum gage and want to try it but I haven't seen a clear explanation of how to do it.
  • Where do I hook up the gage, ported or manifold?
  • Is the distributor vacuum still attached?
  • Is the same setup used to preform all the diagnostic tests the gage is capable of doing?
Am I on the right track? Is there another path I can follow to resolve this. I'd prefer to keep the stock configuration and get as much out of it as I can before I start throwing money at it, rather not go Pertronix unless I have to.

I appreciate any advice and recommendations you may have.

Gregg
 

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Discussion Starter #5
It's a 7-1/4 inch with 2.86 gears.

If others can get to 75 mph, why can't I? Even in fourth. I'm think it's a tuning issue.
 

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Make sure your vacuum advance is actually advancing.

The LOM distributor doesn't have any mechanical advance, so you can probably just hook up the timing light with the advance connected and make sure it changes as you rev the engine up. It probably wouldn't hurt though to hook a vacuum pump to it or suck on the hose and make sure it's not leaking.

The I6 isn't fast, but it should go on the highway just fine.
 

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When the car tops out at 75, does it feel like it is starving for fuel? How do the spark plugs look? What color is the insulator? Is your LOM distributor actually tuned for a manual transmission? The advance curves are very different for a manual and automatic trans. Perhaps something as simple as re-jetting the carburetor could help. I can think of about 27 other things it could be including a engine/transmission/rear end mismatch. You'll probably just have to do some basic troubleshooting. By the way, "reman" parts are about as reliable as my brother in law.
 

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You have highway gears and added an overdrive transmission. With the right power, your system is set up for the Bonneville salt flats. Your car should hit 90+ with a 6 in 4th gear just fine, forget about 5th and let us know how it runs. Dropping to 350s in the rear will wake that car right up with a 5 speed. In my experience, it takes quite a while to sort out a car that's been sitting or a new rebuilt motor with parts that have not previously run together, so don't get disillusioned. Definitely get some miles on it and let everything settle back in. could be getting starved for fuel, do you know the heritage of the fuel pump? I always like to run a new on on any car I want dependable. Rubber diaphrams get old and funk things up.
 

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Discussion Starter #9
The fuel pump is a new original style pump, I could test it. All the plugs read normal light grey/tan after 250 miles. I don't know about the advance, the distributor hasn't been touched since purchased other than service parts, but the shaft didn't have any slop when I had it out. I considered sending it to Nolan(?), but not yet.

Flitch. it's those 27 other things that concern me. What order should they be examined going from easy/cheap to harder/$ ?

If my distributor is actually advancing should I try more or less initial timing?
 

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If you have a Manual Transmission and a 170-200cid 6cyl. ...You'll have to tap in or create a Vacuum Port from the Passenger side of the engine to be able to use a Vacuum guage. If you have a '66 to '70 C4 Auto Transmission, The Vacuum Port is already set up for you....For a '66-'70 I6 6cyl.,, With the car running, You have to temporarily disconnect the Rubber hose going to the Transmission Vacuum, and then plug into the port temporarily for the Vacuum Guage to work. If your 6 cyl. car is a '64 1/2 to '65, You'll have to create an extra Port on the Passenger side of the engine to tap into the Vacuum...Just like the on the Manual I6 6cyl cars. '64 1/2-'65 Cars have a Solid Vacuum line, You can;t really tap into it like you can with '66 to '70 cars...You have to create an extra port for a vacuum guage on the Passenger side of the Motor where the Engine Vacuum is normally screwed into. Tony K. :eek:)
 

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Ship the distributor to Dan at the Mustang Barn and have him set it up. If it works for v8’s it should help a six cylinder.
 

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Advance it. Without too much over thinking just drive around and warm it up then bump the timing up 2-3*. Do this a couple of times and let your butt tell you. Check your linkage and make sure the throttle is opening all the way, have someone press the pedal and look down at the butterfly.

My hot 289 and T5 3.0 rear doesn't like OD till ~60 either.
The I6 of my youth was peppy from a start and would then leisurely accelerate to ~95 mph where the carb ran out. No tach but it didn't seem to be revving all that high.
 

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I am not familiar with a 170 engine so, I dont know where you will be able to tap into manifold vacuum but there has to be a place since they were coupled with an auto transmission. Start by advancing the timing a little at a time. As you advance the timing, you will need to adjust your mixture screw a little richer on the carb (counter clockwise). If you dont have a timing light, just advance the timing by ear. If you go too far, the car will buck a little at midrange and ping. Re-check your dwell at this point. The idle mixture screws are sensitive on the 1100's. Screw it in until the RPM starts to drop and then back out until it just smooths out. If that doesnt help, I think I would go up one size on the main jet. Keep in mind that a 170 has 15 less HP than the 200. That is significant on these little 6's.
 

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Discussion Starter #14
Tony, my carb spacer has an unused port I could use for manifold vacuum. Should the vacuum connected to the distributor for this test?

1ofamillion+, I hadn't thought about checking the linkage. Thanks.

Fitch, sorry for the misspelling.

65fstbkpieces, I don't think I'm ready to send it to Dan yet. But I'm not ruling it out. Just got to work through the problem to get there.

Debrostang, I'm nowhere near getting disillusioned, I'm just getting started, considering everything I had apart and have done, it's been going pretty well. I hope to do a cruise or two next year.

Can someone give me a good explanation of how to tune with a vacuum guage? What I've found lacks detail or assumes knowledge I don't have.

Thanks everyone.

Gregg
 

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Discussion Starter #15
Fitch, just saw your post after my reply. Thanks for the step by step. I did the tune up with a timing light and dwell tach to shop manual specs, but I'm guessing age, wear and tear have effected things. Why would the dwell be effected by changing the advance?

Thanks.
Gregg
 

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Fitch, just saw your post after my reply. Thanks for the step by step. I did the tune up with a timing light and dwell tach to shop manual specs, but I'm guessing age, wear and tear have effected things. Why would the dwell be effected by changing the advance?

Thanks.
Gregg
Yes, you will most likely benefit by setting the base timing to 12 instead of 6. In simple terms, Dwell is a measurement of time. Its the time that the points are open. When you rotate the distributor, that "time" will change. Sometimes only slightly but other times it can be drastic. I set my dwell at 40 and timing at 12 on my '66 200. Dan just recurved my distributor and it made a world of difference.
 

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Also, keep in mind that when the factory specs were set in 1965, gasoline was much different than it is today. We have to adjust for modern fuel which involves advancing the timing and playing with the carburetor jetting. I also had to lower my float level by 1/16" for summer driving.
 

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Discussion Starter #18
Thanks Fitch, that's very helpful. Unfortunately the weather is against me today and winter is starting to set in here in the NE. I'll keep at it until I can't.

Gregg
 

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I'm getting my 65 6 cylinder back on the road after many years of sitting. I've replaced lots of things - brakes, exhaust, gas tank, interior, rebuilt carb and now I'm legal and sorting through everything trying to get it dependable, safe and comfortable..

I'm driving it around any chance I get and although it goes and stops it just doesn't seem to have any power. I can get to about 60 mph with my T5z but can't use 5th because the engine has no power and will just lug along. I've had a 66 6 cylinder years ago and I remember it being a lot more pep.

A little background;
  • Re-manufactured 170ci engine with about 7k miles. Does not burn oil, and has no identified problems
  • Re-manufactured LOM distributor with the same 7k miles
  • Autolite 1100 w/SCV, 200 miles, professionally rebuilt by recommended vender I've used in the past.
  • Tuned up 200 miles ago using timing light and dwell tach to specs in the Shop Manual.V
  • Engine starts easy and runs pretty smoothly
  • Spark plugs were just pulled and read normally, light grey/tan deposits.
They say the stock 6 cylinder configuration should be good for modern highway speeds, that's all that I want. I've heard that a tune up can be done using a vacuum gage to adjust timing for a maximum reading. I have a vacuum gage and want to try it but I haven't seen a clear explanation of how to do it.
  • Where do I hook up the gage, ported or manifold? (Intake Manifold)
  • Is the distributor vacuum still attached? (When adjusting by vacuum, yes. When adjusting with a timing light, no)
  • Is the same setup used to preform all the diagnostic tests the gage is capable of doing? (Yes)
Am I on the right track? Is there another path I can follow to resolve this. I'd prefer to keep the stock configuration and get as much out of it as I can before I start throwing money at it, rather not go Pertronix unless I have to.

I appreciate any advice and recommendations you may have.

Gregg
Remember that the 170 has, IIRC, something like 99 horsepower or, roughly, half that of a 289-2V and is no torque monster, either. The issue lies with your rear axle gearing, which is somewhere between 2.80 to 3.20:1. I had a '70 Maverick MPG with a 170 and 3.03 3-speed. Supposedly the axle ratio was 2.83:1.... Now, the Interstate Highway System has limitations on grades so ours here in Vermont shouldn't be any steeper than those anywhere else.... This was back in the late '70's when the "National Speed Limit" was 55 mph. There were a couple hills on I-89 going northbound... one in Sharon and the other in Williston where if I was going 55 at the bottom of the hill that I had to downshift into 2nd before making it to the top.... If it was summer and I turned on the dealer-add air conditioner I might as well downshift at the beginning of the hill. On the bright side, if I stayed off the Interstates and kept to the secondary roads and went 50-55 mph I'd get 30+ miles per gallon all day long.

I think, if you want to be able to use 5th gear with a 170 on a regular basis... providing you have a 0.68 or similar OD, that you'll have to step up to something around 3.73's.

Also, FWIW, "modern" highway speeds aren't any different than '65 highway speeds. Many freeways were 70 mph and a bunch of western states had NO speed limits. These cars with no overdrive were buzzing around at 70-80 mph all day long.
 

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Discussion Starter #20
Thanks Woodchuck, that's a little discouraging. As you know the 7 1/4 inch rear end is not well supported in the aftermarket. If I have to, I'll look for an entire axle with a 3.20 ratio, the 3.50's are rare to non-existent.

I really just want to get the best performance out of the setup I currently have, before I start replacing otherwise functional parts.

Gregg
 
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