170CUI Indexing of sparkplugs

BetsyBabe64

Well-known member
I want to index my new sparkplugs but have never done it before. I gaped them to .040 and now want to index them. My question is, which way should the gap be facing ? I assume it should be facing towards the other end of the block, as if pointing in the direction of the side of the carb? Thanks !

Yeah, so my generator finally gave up, i took it out and while i was at it took my starter off. The flywheel is fine but the teeth on the starter are destroyed, so i sent the starter and gen and my regulator box to the rebuild guy, make em work and look all pretty again. While i was at it i decided to change my spark plugs and get a flame thrower and ignitor set up. I took my distributor cap off to install the ignitor and i realized the box says its for an 8 cylinder and i looked at the coil and i think it's for an 8 as well, DOH. The coil is the 1.5 version, and i think i need the 3.0 one. I don't know, the guys at napa will help me.
 
Don't waste your time , Indexing a plug for Power gains is a job left for Stock eliminater cars that need a hundreth or two to make the field on a 170 , IF it made a difference , you might gain 1 hp for the money ( thick washers under the taper ) cost money that would be better used in cleaning and Waxing the car for better aerodynamics ( proved on Myth Busters ) I applaud your thinking but time and money vs results would be dissapointing , Check the gaps play with them between .035and .045 if you want to experiment, Inflate the tires to the Max on the Sidewall , make sure the alighnment is good 1/16 -1/8th toe in , if the car has an adjustable valve train ( solids only ) tighten the lash up .06-.08 more than the spec , try playing with timing and jetting , that should keep you busy .
 
Sounds good, i'll play around with those things.
I'm going to index them anyway. I'm going to just face the gaps towards the middle. It's really not that hard, i just take a pen and mark where the gap is and just play around with screwing it in the right way until i get it facing the way i want it. Thank You very much for your reply.
 
You can get a set of indexing washers at the parts place. They come in three different thicknesses to adjust for where they end up when you tighten them down.

BTW, indexing the plugs in #1 on David's list of 'more power for cheap or free'. It goes up in price from there. If you get a new set of plugs, you will have two extra to play with.
 
dave doesn't mention anything about the indexing washers but he shows how to mark it with the pen lol, i found out the hard way that it's impossible to index plugs without the washers haha.

Hey here's a question:

So i was going to install a flamethrower system until i realized i was sold the wrong parts for my application. After finding out that NAPA has to special order for my six, i decided to wait and find out some stuff first like...


How does the pertronix system handle under low voltage ie a generator ? I just got my generator rebuilt, gave my car a full tune up. Will the flamethrower system work well with my generator ? What happens when i'm idling ?
 
Howdy BB and All:

I don't mess with indexing washers. I do what you did. Once the old plugs are out start screwing in the new plugs so that the gaps are mostly up. It usually only takes a few minutes more. That has the gap opening facing the incoming charge mostly. Swap the plugs that are the farthest off into another hole until all marks are mostly up. If one is way off, I can live with it. FalconSedayDelivery is correct in stating that there is a very small gain to be had with indexing, but, it is a gain. Indexing, new plugs, along with a larger than standard gap, and increasing the initial advance by 5 degrees over specs adds up to a noticeable improvement. With the Ignitor you will want to play with plug gaps to find the max, up to .050". If you start to get a miss, either at low or higher rpms, reduce the gap by .002" and try again. Once the misses are gone you will have found the ideal gap for your engine.

When shopping for spark plugs do a comparison to find the most expended tip plug in your heat range. The extended tip does several things for you; it gets the spark kernal more into the middle of the chamber, and fills the chamber slightly, effectively raising compression. Both worth a few minutes searching.

The spark from the Ignitor will not be effected by your generator, the battery should make up for any low rpm loss. You will need the right coil for your system. Given enough time those NAPA guys usually get it right.

Adios, David
 
Exactly, I just buy a set of 8 and keep trying each plug in every cylinder until you find the one the lines up. Works everytime.
 
The plugs in my performance built 250 are indexed by marking the electrode and then swappng for best average. Part of hedge all bets simple performance mods ...




THe Champion - 2021 Racing application plugs for the Falcon six I believe are still available.



Have Fun

8)
 
Awesome, i'm going to give it another go ! I have just one more question, i know i keep jumping around but it's better to ask in here then keep making threads.

in my 3 on the tree, when i'm in neutral and shift into gear and do my pedal work, i'm now hearing a squeak coming from somewhere. i just install a fresh generator and had the belt too tight and loosened it up today, is it possible that has something to do with it ? It especially happens when i'm going fast and shift into 3rd. Any ideas ? Thanks Everyone !
 
well more like let out the clutch. That's upsetting considering i just got my clutch rebuilt. This started happening right after the rebuild and has now gotten worse. I've also been noticing that my clutch makes a weird feeling when i press it in. I'm starting to think it wasn't installed correctly.

What's happening ? Do you know ? Thank You very much for your reply.
 
Sometimes the throwout bearing gets overlooked during a clutch job. Do you still have the receipt or work order? see if it was replaced. The weird feeling could be corrected by just adjusting the clutch.
 
i bought a clutch kit and oversaw some of the work, all the new parts are in there. i'm thinking two things:

1, when i was cleaning and repainting the transmission, i had it on it's nose (bellhousing) and noticed it was leaking tranny fluid from where the input shaft (is that what it's called?) area is. to the point where i had to refill the transmission.

2, the new clutch kit wasn't installed correctly, something is upside down or backwards or something along those lines.

when everything was put together and i drove it for the first time, i didn't feel the weird rolling clicking from the clutch pedal, it started a few days later. My mechanic buddy told me it was probably some kind of vibration from somewhere and didn't seem to be a problem.

Maybe my whole transmission needs to be rebuilt ? Any thoughts ? Thanks.
 
There's a clip that holds the clutch fork in place where it pivots on the fulcrum inside the bellhousing...
Is the z-bar lubed and properly installed. Doesn't look like it's going to pop lose when somebody press the clutch pedal...
Maybe somebody in the transmission section might have some suggestions. Kinda hard to say without taking it for a test drive.
 
when they were installing the new kit they broke that clip to the clutch fork and i had to run to a local bronco restoration shop and buy a new one. (same year bronco uses the same clip for the 170-302 engines) and i gave it to them and they installed it. I don't know how they did it, but maybe they messed it up. I'll figure it out, thanks for pointing me in the right direction. If anything new comes up ill post in this thread. Thank You very much for the reply.
 
i bought a clutch kit and oversaw some of the work, all the new parts are in there. i'm thinking two things:

1, when i was cleaning and repainting the transmission, i had it on it's nose (bellhousing) and noticed it was leaking tranny fluid from where the input shaft (is that what it's called?) area is. to the point where i had to refill the transmission.

Yes is imput shaft there is a seal in there may need to be replaced was there oil inside the bell housing when you took apart?

2, the new clutch kit wasn't installed correctly, something is upside down or backwards or something along those lines.

when everything was put together and i drove it for the first time, i didn't feel the weird rolling clicking from the clutch pedal, it started a few days later. My mechanic buddy told me it was probably some kind of vibration from somewhere and didn't seem to be a problem.

It is posible that is not installed correctly but is not that easy to do, only part that is sometimes installed upside down is the clutch disk. For many years now they usally have a sticker that says flywheel side it is hard to bolt togeather wrong but I worked on some that were done that way. Did you have a vibration before installing the new clutch? If not you should not have one now.

Maybe my whole transmission needs to be rebuilt ? Any thoughts ?

Signs a trans needs to be rebuilt would be bearing or gear noise these would increase as the speed increases, popping out of gear when decelerating.

Is there any free play in the clutch pedal? Needs about min of 3/4 inch from pedal up and as you push it down. If not the throw out bearing will be spinning all the time and wear out sooner. Another thing to test is as you start to push clutch down very lightly as it contacts the pressure plate fingers if there is any feel of a bounce it is a sign that pressure plate height maybe improperly set. This can also show up as chatter or grabbing when releasing the clutch at take off. Did you happen to have the flywheel surfaced before install of the new clutch or notice the surface? It would be hard to say much more without more info, seeing the parts or driving it Good luck
 
Yeah i had a horrible vibration before the new kit. It was so bad i couldn't drive faster then 49 MPH it was terrible The flywheel surface has been totally polished.

I don't really have any play in the pedal, but the response isn't how it use to be when i first got the car back.
Thank You so very very much, i'm going to figure it out today, thank you !
 
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