Tire rub? Sounds identical to rub I had on rear of my Mustang before I installed a panhard.
Tire rub? Sounds identical to rub I had on rear of my Mustang before I installed a panhard.
HotNotch said:Tire rub? Sounds identical to rub I had on rear of my Mustang before I installed a panhard.
yeah, i'd be looking at both rear tires for evidence of contact with quarters. i'd also be looking at the front of the left front inner fender, and the left front tire.
thanks guys - will investigate further!
Went out to the MC the yesterday and the dome light didnt come on when I opened the door. The battery is less than a year old, and until now has been rock solid. I jumped it this morning, and she stayed running, but the multimeter bounced around between 12.8v and 13.2v between the battery terminals. How does one know when their alternator is a problem, or when to look elsewhere? Its a single wire GM alternator with a positive lead, but does have the little 2 wire pigtail for I dunno what.
help.
Pic?
not the best pic - I thought I was looking at a part no. when I was looking at the vent. But based on the pic above, Im pretty sure Im looking at this alternator:
Carquest Premium Alternator 7133A: Remanufactured, 63 Amps 7133A - Advance Auto Parts
because of this pic from the internetz
if I need to replace it, I would probably upgrade to a higher amp alternator unless theres a downside to that. Jegs has an option for not much more:
black would look good in my engine bay
You should have an alternator light on your dashboard. One that lights up with key on engine off and then goes out with the engine running. If that bulb goes out the alternator no longer receives a 12 volt signal from the chassis harness and then no longer excites and charges. I would begin Diagnostics by checking for 12 volts at the two field wires both at that little rectangular connector as well as cleaning the connections at both ends of the charge wire which are the one off the post at the back of the alternator that should terminate at either the starter or the positive terminal of the battery. That generation of alternator rarely goes bad it's usually the wiring to and from it in my experience. There's also no sense in replacing it if your plan this winter is to go to a serpentine accessory setup which will update your alternator Choice dramatically
Ok, thanks for that - great advice. Youre right, now that I think of it, the "Gen" light no longer lights up. Bonus, cleaning is free!
Regarding the belts, doesnt look like Im going to get my dream setup. But we are narrowing down on possibly way more engine than I had hoped for, just with a multiple V-belt accessory set to keep the cost to a minimum. Once I have firm details, I will post them. I can say that there are 383's within the acceptable dollar range so long as I reuse the accessories shes currently wearing...
Also if the bulb burns out on the generator light it will no longer transmit 12 volts out to the alternator and cause the Exciter to activate the alternator in charge. So it may be something so simple as a burned out bulb. As far as Serpentine accessories go don't discount a junkyard solution for serpentine. Look at the late 90s 5.7 Vortec trucks as a single Source donor. You should be able to find some for cheap around you that are getting parted out.
Well, at least I can rule the Gen light out. Key in run but engine off:
So i did some things this morning...cleaned the pigtail leads on the alternator, cleaned the positive post on the battery. Not too corroded, slight greenish hue. Still need to get underneath and check the wire from the alt to the starter. But that alone improved things - got a steady 13.4v at the battery when running.
What kind of voltage am I looking for across the 2 pigtail leads on the alt tho? With the car running, It was making around 7v but slowly dropping about .1v every few seconds. Is this normal?
I will say that the alternator is making enough juice that she stayed running with the positive battery wire disconnected from the battery. I'm wondering now if it's the battery? It's a Napa Legend, maintenance free model, less than a year old. I had it on a trickle charger for about 24 hours after I had her running yesterday, and was only at 11.8v this morning. Jumped her again. Ran her about 15 min while doing those diags above. Shut her down, and then wouldn't start...back to 11.8v. Ugh...
Almost certain its a battery, and most likely under warranty.
Behavior of field wires sounds normal for that era. The loghtbulb acts as a resistor, and the field wores sense system voltage telling the alternator how much juice to put out.
In reply to 4cylndrfury :
Sounds like your battery is not helping, for sure. I would try a full charge on the battery (Not trickle) and see if that wakes it back up. If not, then it's probably time for a new juice box.
Thanks fellas - i do need to procure a full charger.
I will probably take the battery up to the store to have them check it sometime in the next day or 2. Luckily I actually kept the receipt 
update:
The battery tested fine, probably left the door slightly open, or the key will pull out of the ignition while barely contacting "Run" mode - one of those was likely the culprit.
I also finally started looking inside my carb for the stumble issue. I got some advice from another classic owner who had a friend with a similar issue as mine, and he said the power valve in his buddie's carb was shot (backfires can damage them). So I decided i would swap out my carburetors power valve. No pics, but theres not much to show anyway. I didnt know what I was going to find in there as the previous owner told me that the carb came off another project that had been hooned with once upon a time. It was just whatever was laying around when they were getting this car running again. As a refresher, mine is a 670CFM unit that is on the borderline of being too much carb for a stock 350. Other than being overkill, its actually in very good shape.
I ordered the valve that the Holley website says comes with that carb out of the box - a 6.5Hg valve. The more HP and lower the vacuum you make, the lower size valve is going to be needed. One symptom of a valve that is too low for the current motor is stumble off idle as the carb doesnt transition to the main jets soon enough. The vacuum a stock motor makes is too much for a lower rated valve, and you go lean momentarily until the main jets kick in- which is exactly how my car ran. Sure enough, the valve that was in there was a 6. So in the 6.5 went. I installed a new accelerator pump diaphragm while i was at it because its cheap insurance and easy to do with the front bowl off.
Wouldnt ya know it, the half step made a difference. It still would stumble a little, but i couldnt get it to backfire and it didnt act like it wanted to stall, just kinda dipped in RPMs momentarily! SUCCESS! So, naturally, I ordered more parts lol - on its way are 1 each 7 and 7.5 Hg valve. I think i will likely be able to get the stumble to disappear all together with one of these 2 - just gonna swap and see.
Question - is it recommended to use teflon tape on threaded fuel connections like you would for plumbing? The fuel line has a fitting on the bowl that looks like it had some tape on it once. Should I replace the tape properly?
Still havent figured out the weird noise when accelerating from a stop on right hand turns - no signs of tire rub at all. I cant shake the feeling that its my power steering - it will get louder the more pedal i put into the turn. If i creep away from the stop, it doesnt make the sound at all. I know nothing about how a power steering rack works, so I guess I need to begin educating myself.
In reply to 4cylndrfury :
Power valves should be 1/2 of the vacuum at idle.
If your cam and setup makes 14in of vacuum then run a 7 power valve. Of course you need to buy like ALL of them to get 100% tuned... welcome to Holley
In reply to 4cylndrfury :
670 CFM is way too big for a stock 350... you may not be moving air through the carb fast enough.
Some quick back of the napkin math:
CFM = Cubic Inches x RPM x Volumetric Efficiency ÷ 3456
So, 350 cubic inches, and a 5800 rpm redline, assume 85% volumetric efficiency for a stock motor.
350 x 5800 x 0.85= 1,725,500
1,725,500 / 3,456 = 499.2, round up to 500 cfm.
Your carb is about 170 cfm bigger than it should be.
For additional reference, the stock 440 in my Dodge runs a 600 cfm edelbrock.
670cfm is bigger than needed but it should be close enough to run acceptably. I've run 625cfm on a stock 305 with no problems and my 440 is happier with the 750cfm it runs now than the 600cfm it had before.
It sounds like a bit more tuning and it will be sorted.
I've run a 750 vacuum secondary on a stock 289 and it ran really well.... A lot of the "sizing" is really just the way the metering circuits are drilled in the casting. Perversely, mild cammed engines seem to be more tolerant of oversized carbs because they have a better vacuum signal at idle and low load, which helps get the idle circuit moving, and it stays moving before the main circuit can take over. It's when you get a big cammed engine that wants to idle with the transfer ports partially uncovered that you run into issues.
You have to figure that the CFM rating is at a 1.5" pressure drop for a 4 barrel carb. You don't want a high pressure drop, so it's not only okay but beneficial to go larger.
I have Opinions regarding power valve sizing... but they involve driving with a vacuum gauge to determine where you cruise and and when you start to load the engine down under acceleration.
Thanks for all the direction guys. Im genuinely grateful for all the knowledge everyone is willing to chip in!
Its all kinda moot in the long run - yes, I know 650cfm is on the extremely high side of things for a stock 350. its what she was wearing when I bought her. The guy told me it was too much, but that is what they had laying around when they were getting her back on the road, and its okayish for cruising around. But I really hadnt planned to still be running this engine by now - I had saved enough for a SBC stroker swap over the winter, but some life things got in the way. So, its fine for now to toss a few dozen dollars at getting her running well enough to have fun while the sun shines.
At least I can enjoy daydreaming about spending some quality time on a creeper this winter with THIS BEAST this winter....
then its on to a rear disc brake conversion and figuring out how to beef up a stock 10 bolt rear before spring arrives and budget evaporates. From what I understand that 450HP at the crank is about the peak of what a 10 bolt can manage. Im guessing I will want to regear...
GM put 800cfm carbs on 307s. Granted those were Qjets with small primaries...
In reply to Pete. (l33t FS) :
I've noticed that both the Q-Jet and the Thermoquad don't really translate over to "traditional" carb sizing very well.
OE Thermoquads on the big block Mopars were rated at 1000 cfm
Already looking at building a shopping list for this offseason, and have a few questions that Im hoping others on the forum have answered before. Please understand this isnt a drag car, and the most hooning it will see would be between lights on the way to a cruise in. She will mostly be used for plain weekend drives on backroads, but may see highway miles a few times each summer. my curiosities are:
In reply to 4cylndrfury :
The Detroit truetrac that I had in my '93 Suburban had excellent street manners.
EATON 912A556 Eaton Detroit Truetrac Differentials | Summit Racing
Recon1342 said:In reply to 4cylndrfury :
The Detroit truetrac that I had in my '93 Suburban had excellent street manners.
EATON 912A556 Eaton Detroit Truetrac Differentials | Summit Racing
without opening up the rear case, how do I know how many splines my axles have? how do I know if I need an 8.2" or 8.5" unit?
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