'73 Challenger Rallye Restoration

[moparleo]

The battery is grounded through the negative cable that should be bolted to the engine. You also need the block grounded to the cars body. This is the primary ground for all of the electrical connections on the body/chassis.

 

[AUSTA]

What is the voltage on the key ignition side of the resistor to engine ground with the ignition turned on the blue wire.

 

[Bill]

What is the voltage on the key ignition side of the resistor to engine ground with the ignition turned on the blue wire.

I have 12.5 volts on ignition switch side of ballast resistor to ground. I think I discovered that the ISIS power system is reducing the voltage some how. I can fix that with a relay. Meanwhile I hot wired the ballast resistor direct with 12v and the ECM bypassing the ISIS power unit and measured voltage at the coil and I was getting 2.4 volts from coil positive to the car ground. I purchased a new coil today as the old one was just a few ohms out of spec. I have a new problem now. The car starts fine (full 12v hitting the coil in the start mode) but it stalls out then I stop the current to the starter / ballast resistor bypass. I know you said that you are getting around 2.4 volts and when I was yesterday the car was running perfect until the ballast resistor blew. I just put a grounding strap from the back of the ECM mounted under the ECM bracket bolt on the firewall to the block.
Leo. Do you think I should run a cable direct from the battery to the block?
Oh, and when it does start up is sounds AWESOME!!!!

 

[moparleo]

If the car starts up and dies when you release the key, the ballast is bad.

 

[Bill]

If the car starts up and dies when you release the key, the ballast is bad.

It's a 1.2 ohm ballast. I just measured it and it reads 1.1 ohms. The ballast is new today. I truly think my problem is the coil is not seeing any more than 2.4 volts during run. Can a ballast resistor be kind of bad. Kind of like kind of pregnant? lol

 

[moparleo]

Yes. By name it is a resistor. The resistance changes with temperature, that is why the ballast gets hot when in use. Coils go bad gradually as well.

 

[AUSTA]

If the ISIS system uses a transistor rather than a relay & it is overloaded yes it will start to drop voltage which also put the unit under stress causing it to overheat
If the ballast resistor is overloaded you will find your ballast resistor resistance will increase rapidly as it heats up thus snowballing the the heating effect
your meter leads will be increasing the reading short them together and hit auto zero on the meter if it does not have auto zero short the meter leads together & subtract the reading from your resistor reading this is typical as most meters aren't made to measure very low resistance
A few ohms on the primary of the coil is lot considering the ballast resistor is only 1.1 ohms
By increasing the watt rating of the resistor but leaving the ohms the same will enable the resistor to handle more current without failing or overheating which in turn will allow a higher voltage to be present at the coil
The drawing for the xcel coil also says to use the 1.35 Ohm resistor supplied if you fit this & your voltage at the coil is low then bypass the ISIS to see if it increases also don't leave your ignition on for long without the engine running .

 

[Bill]

If the ISIS system uses a transistor rather than a relay & it is overloaded yes it will start to drop voltage which also put the unit under stress causing it to overheat
If the ballast resistor is overloaded you will find your ballast resistor resistance will increase rapidly as it heats up thus snowballing the the heating effect
your meter leads will be increasing the reading short them together and hit auto zero on the meter if it does not have auto zero short the meter leads together & subtract the reading from your resistor reading this is typical as most meters aren't made to measure very low resistance
A few ohms on the primary of the coil is lot considering the ballast resistor is only 1.1 ohms
By increasing the watt rating of the resistor but leaving the ohms the same will enable the resistor to handle more current without failing or overheating which in turn will allow a higher voltage to be present at the coil
The drawing for the xcel coil also says to use the 1.35 Ohm resistor supplied if you fit this & your voltage at the coil is low then bypass the ISIS to see if it increases also don't leave your ignition on for long without the engine running .

Awesome info. Yes, voltage is different when powering up with ISIS alone without using a relay. My brain is fried for today. Thank you! Goodnight.

 

[Bill]

Need help with windshield and rear window molding clips. I have 3 different types. Was wondering if anyone had information on installing the trim. I'm confused because I have 3 types of clips. The one with the screw is self explanatory but I have two different ones that go over the nail heads? Any help would be greatly appreciated. Thank you!

 

[Bill]

TTi exhaust system on order. It's going sloooowly but surely. I'm a novice so if you can see anything in this video that I did wrong or need to change please feel free to let me know. I have been told that the fan needs to be closer to the radiator and the coil should be closer to the dizzy. This car was built by www.forebodiesonly and Youtube (lol). I do hope to get it on the road in some form before the snow flies here in Vermont. I do live on a back road and have about 15 miles on it already. A windshield would sure be handy to have because I keep getting bugs hitting me in the face. There is a professional glass installer that is going to come over next week to install the glass.
https://www.youtube.com/watch?v=hOOhICPPUUU

 

[js29]

that does sound like A strong running engine! good looking to say the least.

 

[Bill]

Thanks js29!
It does sound strong doesn't it. A local race engine guy blue printed it. River City Machine in White River Junction, Vermont. Slightly bored, mild performance cam but not stroked. Hope to get a lot done on vacation next week. May stop by the DMV tomorrow to get registered and pay the sales tax on it. The TTi exhaust came in this week. I just realized that there is only one exhaust bracket that is behind the rear seat. Went to take it off and the bolts busted off so I have a little work to do to get ready to hang the rest of the exhaust. I am going to fab up the other hanger bracket. I got a 74 parts car and the mounting brackets are not on that car at all. I will need to modify the stock tips to accept the 2-1/2" pipe unless my originals are worth the price of new ones to someone who wants the stock ones. I will try to post another video with the TTi and the Dynamax mufflers when I get them hooked up.
I'll get this thing on the road one of these days!!
Bill (Vermont)

 

[74chlngrTT5.9]

:icon_thumright: :icon_thumright: :icon_thumright: :icon_thumright:

Mike

 

[Bill]

Drove about 100 miles today. It's amazing how many people come up to you asking about the car and all the thumbs up you get on the road. These E bodies sure are a special car. This teenager came up to me today where I was getting a sandwich for lunch and told me that I own his most favorite car in the world. My mom who lives with us went with me on the first inaugural ride into town to get some gas last night. There were 4 guys at the gas station that were gawking over my freshly restored Challenger asking questions about the car and telling stories of "back in the day".
I am having a problem though putting gas into the tank. I have no vent. The tank is the type with the four tubes that are in the top corners of the tank and go to four outlets in the front of the tank. The vapor can that was mounted in front of the tank was Swiss cheese and not repairable so I just plugged the outlets on the gas tank. I can only put about 5 gallons of gas in then it starts to puke out of the fill.
Does anyone know of a good method I can use to get a vent back in the tank? I even tried filling the tank as slow as possible with no results. It also does not help that either my fuel gauge or sending unit or both are not working.
Thanks!

 

[js29]

try p-m to moparparts. don is A good guy to deal with,

 

[ECS]

A local race engine guy blue printed it.

Hi Bill. What was the process or work that he did to "blueprint" your Engine?

 

[challenger6pak]

I have the small tank if you need a good one to hook your lines to.

 

[Bill]

Just about the only thing I know about engines is suck, push, bang then fart and I hope I got that in the right order. Not sure how to answer your question but I will ask next time I see him and let you know. I know he purchased parts from more than one vendor until he got what he liked. He was trying to keep things economical too by trying not to have anything custom made to get the proper dimension he was looking for.

 

[ECS]

Just about the only thing I know about engines is suck, push, bang then fart and I hope I got that in the right order. Not sure how to answer your question but I will ask next time I see him and let you know. I know he purchased parts from more than one vendor until he got what he liked. He was trying to keep things economical too by trying not to have anything custom made to get the proper dimension he was looking for.

If he charged you for "blueprinting" you better make sure he wasn't trying to gouge you. The only "blueprinting" that is done these days are for Engines that go in Indy Cars, Pro-Stock Dragsters, Winston Cup Cars, etc....... It costs a fortune to "blueprint" an Engine. Here are a couple of links that tell some of the specifics.

http://www.enginebasics.com/Advanced Engine Tuning/Blueprinting.html

http://www.badasscars.com/index.cfm...duct_id=84/category_id=13/mode=prod/prd84.htm

 

[Bill]

Must be the wrong terminology.