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Revisiting my post a couple of days ago about how my 289 runs fantastic as long as I don't try to wind it out in first or second. As far as winding it out in third...I'll refer you do yesterday's post by DaveOxide, and just say, I pretty much learned that lesson a long time ago. /forums/images/icons/wink.gif It revs freely in N as well, under no load.

Anyway I digress. [color:blue]A clue! A clue!</font color=blue>

http://home.earthlink.net/~pirateship/DSC21006.JPG
Is that a blue paw print on the distributor cap???

289. 10.0:1 Comp XE262H Cam. Stock distributor with Petronix. Big cap. Ford Racing plug wires. Ford Motorsport 40KV Coil.

Last night I tried taking off the "restrictive" hypo air cleaner. Didn't make a bit of difference.

Next I took another look at the engine. Hmmm Distiributor might be a little loose. Better check my timing.

I unhooked my vacuum advance and started it (idle dropped to about 500 RPM with no vacuum advance). Timing light shows about 9 degrees before TDC. About what I thought. I reved it up and I'd say total timing jumped to around 24 degrees at maybe 3000 (complete guess. My cheapy, $35, Walmart Special, inductive timing light doesn't have a tach). Then, advancing the throttle farther I got a possible clue. While the timing held steady, the pulses from the timing light became sporadic. I couldn't really hear a miss, but the either it was missing, or the timing light won't work properly above 4000 rpm or so.

Next up I checked total timing with the vacuum advance hooked up. It was more...say 6 to 10 degrees more. I'm just guestimating based on the 12 degree mark on the balancer, so I can't be really precise.

So, I took it for a drive with the vacuum port plugged (Holley 4160...vacuum port on the passenger side, front, near the primary sight glass). Maybe it reved a little further...Say to 5000 (instead of 4800) before it just wouldn't rev any more.

I guess I'm thinking the spark is beginning to drop out above 4000RPM, and the condition worsens above that. I'm also wondering if I'm even getting a true reading of engine RPM off of my tach at high rpm. I mean, doesn't the tach "count" ignition pulses? If I'm loosing 10% of my pulses at 5000 RPM, wouldn't the tach read 4500, regardless of engine speed?

Also, on the Petronix. I know there's been plenty of posts on the way it should be hooked up. It's been 4 years since I hooked mine up and I'd guess I probably went with whatever was easiest. Could improper hook up allow it to work, but cause it to get futzy at higher rpm? Or, do cheapy timing lights just not work at that high of revs, meaning [color:blue] my clue</font color=blue> is actually just a [color:red] red herring </font color=red>?

Thanks!

Phil
 

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I decided against the pertronix based on all the negative feedback I have seen on them. Just for giggles why not borrow and swap out a true duraspark setup and see if it helps. Worse case is go to the junk yard and buy one for $50. If you are getting voltage drop or intermittent spark due to the pertronix unit at high rpm that should expose it.
 

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You must have young children with the reference to Blues Clues. My 2 year old loves that show /forums/images/icons/smile.gif I'm still guessing it is the carb. Did you read the plugs? If the secondary or power valve is not operating properly, it will not rev under a load. A problem I had in the past with my Holley was that the secondary meteor plate had clogged orifices (the small holes that the fuel flows through). I let it soak for about an hour in cleaning solution and used compressed air to blow it out and it ran much better. At the time, I still needed a complete carb rebuild but I solved one big problem I was having. Hope this helps.
 

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Check the positive side of the coil for 12V with the key on.
Are the secondary's on the carb opening up at speed, sounds like you may be running out of fuel or not enough if the secondary's aren't opening up. Float bowl fuel height?
 

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Also, another thing, under very lean conditions, you will not have proper spark. Run it hard and turn off the motor as soon as it is safe. No not let it idel or cruse. Pull the easiest spark plug and if it is white and flaky or signs of metling then dig into the carb. This would be easier is you have an Air/Fuel ratio guage installed. Good Luck.
 

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My car acted almost the same way before my ignition box took a dump (duraspark). I replaced it with an MSD and had no further problems. I'd check the distributor cap for problems too, but you've probably don't that already.
 

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Discussion Starter #8
Young Children?

You mean Blues Clues is a kids show? Huh. I never made the connection!

My carb's pretty new (4 years old, has about 10,000 miles on it). Let me just say, that although I'm not sure, I'm leaning away from the carb being the issue...unless it is tied to an ignition issue. For instance, I should pull the plugs and make sure they aren't fouled. I'll do that tonight.

Phil
 

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OK, here's what I get at the coil:

Key On, engine not running

Batt = 6V
Dist = 1V

Key on Engine running at idle

Batt = 9.7V
Dist = 6 V

Does that mean anything?

Phil
 
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The Pertronix needs 12v supplied to the coil. Easy test.remove the wire from the pos side of coil. Now use a jumper from the pos of the bat to the pos of the coil, go for a test run. If the engine performs correctly that was the
problem= not enough voltage to the coil. The solution would be to bypass the resistor wire from the ignition switch to the coil using 14g wire
 

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1v!!!!! That can't be right. Are you running your voltmeter ground to a good ground on the body and putting the positive on the hot wire going to the coil??

What is the voltage at the battery when the car is running? It should be 13 volts or higher, but no higher than 15 volts. Either I am off my rocker or you checked the voltage in an usual manner.
 

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Myvote is your baby is starvingl. It could be a suply problemof pulling all the fuel out of the fuel bowl (bad pump or filter) or your jets are too small in your secondaries. Your secondaried may also have a problem and not be opening (vacume problem).
 
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