Monday, August 31, 2009

Ignition Timing Check

I tested my ignition advance on Saturday morning. To test it, I removed the vacuum tube from the distributor and plugged it with a golf tee. I then used a timing light to check the base advance and the mechanical advance at a few RPM points. I recorded the following:

850 - 11 Degrees BTDC
1000 - 11 Degrees BTDC
1500 - 15 Degrees BTDC
2000 - 23 Degrees BTDC
2500 - 29 Degrees BTDC
3000 - 36 Degrees BTDC

With an initial timing of 11 degrees and the 15 degree plate in the distributor, my total advance should be 41 degrees. I did not check the advance at 3500 RPM but I'm sure all 41 degrees is present by that point.

To get better performance, I could replace the other stiff, stock spring with the light version I received in the kit. This would provide all the advance by around 2800. Since I cannot change my vacuum advance settings, I'm concerned this could result in pinging which I would not be able to correct. Since this works well, I will leave it alone for now.

Sunday, August 30, 2009

Carburetor Tuning Continued

I called O'Reilly from work yesterday and they said they could get the Holley pump cams by 5 o'clock. I ordered them and paid a premium price ($27.99). However, I would have paid the same to get the from Summit after the shipping cost.

I put on the new coil this morning and the new spark plug wires. I then switched from the stock orange pump cam to use the new size up which is black. I then checked the front float level and found it is not set as high as I remember. I raised the front float level and then took the car for a drive.

The hesitation on accelration if fixed. It seems there is a small hesitation at very low RPM. This is likely because the idle mixture is off or because I could function with the orange cam with the raised float level. I'll fine tune it later. For now, I'm just happy the drivability is much better.

The current setup is shown below.

Thursday, August 27, 2009

Carburetor Tuning Continued

I received the new distributor springs, Petronix FlameThrower Coil, and MSD Street Fire spark plug wires in the mail today. The springs are rated to deliver full mechanical advance by 2,400-2,800 RPM. I was concerned that would be too quick so I used one and one of the stock springs.

I drove the car around tonight with only the new spring installed. This seemed to help low RPM performance some but did not fix the hesitation. I posted on a few Mustang forums to get some additional help with the problem. The only response so far requests I try new pump cams.

Tuesday, August 25, 2009

Ignition System Upgrade

I removed the distributor cap and top plate today. I wanted to check the internal parts to determine how much mechanical advance was possible. I found a 15 degree arm installed which would provide 30 degrees over the base timing.

The RPM at which the timing increases is controlled by two springs. The stiffer of the two springs was stretched and did not fit properly on the mounting points. The other spring fit well but had less resistance. I'm going to replace these springs while I have the distributor apart. The new springs should allow for full advance by 2800 RPM.

I tried to locate new springs all over the city but no one sells them. I ordered them from Summit with a new coil and some spark plug wires. They should arrive by Friday and I'll install the parts this weekend.

I hope the additional advance corrects the hesitation I feel when accelerating.

Sunday, August 23, 2009

Carburetor Tuning... Still

I've tried numerous different things to get rid of the hesitation on acceleration. I've tried new accelerator pump nozzles, changed the pump cam position, and changed secondary springs. Unfortunately, none of the combinations of things I've tried have fixed the problem.

I removed the spacer today. The spacer should add power but can move it up the power band and create a lean condition. I was not sure this would make much of a difference but it was worth an attempt. I found the hesitation remains but seems to disappear at high RPM (over 2500).

I've asked on the VMF about the situation and I've received a variety of responses. Several suggested new jets, others said new pump cams, and others have questioned the timing. It is unfortunate so many things can cause the same type situation.

I'm going to expore the timing next as I think I've eliminated many of the carburetor variables as being the entire cause. I took the distribution apart and found 15 degree plates. One spring was very tight and the other is soo lose it could fall off. I think I try to find some at a local auto parts store and then check my mechanical advance with a timing light.

Tuesday, August 18, 2009

Carburetor Tuning Continued

I received the new accelerator pump nozzle a couple of days ago. I'm replacing my fence and have spent the last few days taking down the fence and removing the poles. I had some time tonight so I installed the nozzle and took a test drive.

The hesitation changed with the new nozzle. If felt like two short hesitations with a quarter second feeling of normal acceleration between the two. I took off the carburetor with plans to remove the spacer and found a leak at the back of the carburetor spacer. I installed a new gasket and then went for another test drive.

There is now only the single hesitation which is short but still present. I'll try to switch back to the .031mm accelerator pump nozzle next to see if it works better with the carburetor spacer leak fixed. Unfortunately, I've run out of time for today so I'll need to try that later this week.

Wednesday, August 12, 2009

Suspension Alignment

Since I had the day off, I called around to find someone who could perform an alignment on the Mustang. I found a local place call Pilger which could do they job. I stated my concerns about damage to the undercarriage I just completed. He stated they would not damage anything so I took the car up there this morning.

I was given a results sheet showing my camber and toe were correct but not the caster. Here are the figures from the sheet:

Before: +.4 camber, -.1 caster, and -.05 toe
After: -.1 camber, -2.3 caster, and .00 toe
Before: -.3 camber, -.3 caster, -.06 toe
After: 0.1 camber, -2.8 caster, and -.06 toe
The car seems to run much better now. They said it is normal to add more caster to the right side due to the way roads slope down on the sides.
I checked under the car when I made it home. I found they were not as careful as I asked with the suspension parts. The sleeves for the adjustable strut rods are very scraped up from tool teeth marks.

Tuesday, August 11, 2009

Carburetor Tuning

I drove around some after installing the new carburetor. The car seems to drive fine under moderate acceleration. Once I press the gas about half way, the car hesitates for about a half second and then takes off. I've watched a video which came with the carburetor and performed some internet research and this is suppose to be related to the accelerator pump nozzle size.

I've ordered a new .035mm accelerator pump nozzle from Summit. However, the part will not arrive until I return from my vacation in Las Vegas. I'll need to wait until then to see if this fixes the hesitation.

Saturday, August 8, 2009

Installation of Intake and Carburetor II

I made a final cut on the gas line and installed it this morning. I then filled up the radiator and changed the oil. I then tried to start the motor and it started but was not running well.

I checked the timing to find it was 25 BTDC. I could not adjust it to less because the vacuum module of the distributor was hitting the intake. I rotated all the spark plug wires on the cap and rotated the housing. I then could not get the engine to start because the timing was off.

My wife held the timing light as I cranked over the engine. It would start for just a second and she could see the location of the TDC mark. I made two adjustments and the engine started with the timing at 15 BTDC.

The RPM of the engine never seemed to drop. It was then I noticed the stator terminal on the alternator was only putting out 7 volts. I used a jumper to the batter but still did not have much luck. I turned off the car and thought I would watch the Holley tuning video which came with the carburetor again.

The video stated you needed to wait for the engine to warm up and then start with the idle mixture screws. I took a picture of their initial position and then moved them out 1.5 turns as the instructions stated. The engine idle never dropped so I got concerned and tried to turn off the engine. It kept trying to run and died after blowing a mist of gas vapor out the top of the carburetor.

I waited a few hours and then perform the following steps:
1) Checked coolant level
2) Changed choke setting (set wrong from box)
3) Started the car & waited for it to warm up
4) Adjusted the curb idle to 600 RPM
5) Set timing to 15 degrees BTDC
6) Adusted the curb idle to 600 RPM
7) Set the idle mixture screws to get the best vacuum reading
8) Adjusted the curb idel to 600 RPM
9) Set the float levels

This is exactly right according to the instruction video. The engine seems to be running better. I'm going to let it cool and then check the choke setting. Earlier in the day I would get a pop out the exhaust when I blipped the gas. I'll check then to see if it is still happening.

I took the following picture after the first startup. Shortly afterwards, I removed the air cleaner and started tweaking on the carburetor.

Friday, August 7, 2009

Installation of Intake and Carburetor

I started on the installation of my new Weiand Stealth intake and Holley Street Avenger carburetor last Sunday. I started rather late in the day as we were out of town for most of the weekend. However, I removed the distributor, drained the coolant, and removed the stock intake. I then installed the thermost and mounted the housting the new intake. Finally, I primed and painted the Stealth intake Ford Blue.

On Monday, I intalled the temperature sensor, vacuum port, and a plug in an extra hole in the back of the intake. I cleaned up and installed the factory bracket for the throttle spring. I then painted over these with the Ford Blue. Finally, I painted the black plastic 1" spacer with some aluminum paint to make it look more like the original spacer.

On Tuesday, I ordered a heater elbow and a few other parts from NPD. I checked locally but no one had a heater elbow which fit the intake. After work, I intalled the intake. I took my chances with the cork seal coated with RTV at each end. I used Felpro gaskets and some high tack sealer on the head side of the gasket. I tightened it to spec (15 on ouside bolts and 25 on the inner 8) in 5 ft/lb increments.

On Wednesday, I noticed the cork end seal pushed out a little overnight. I was a little discouraged and concerned about a leak but moved on. I touched up the valve covers with a little Ford Blue. I then bent a new fuel line out of 3/8 brake line. I tried to locate metal fuel line but the auto parts store indicated this was all they carried.

On Thursday, I cleaned up the distributor and worked on reinstalling it. It was difficult to mount because the oil pump shaft was laying against the side of the distributor hole. I asked on VMF and found this is common. I used their advice and put a little Vasoline in the hole to hold the shaft in the middle. This did not work perfectly but made things slippery enough it slid into place after about 12 attempts.

Tonight, my parts arrived from NPD at about 7 o'clock. I was concerned they would not arrive. Once they made it here, I mounted the carburetor, installed the throttle linkage/spring, ran the spark plug wires, connected the heater elbow, and connected all the heater hoses.

I need to make an adjustment to the fuel line, change the oil, and add water to the system in the morning. Once these are done, I'm ready to start the car. I'm told the carburetor should be set well out of the box. My main concern is how off my timing is after removing the distributor.


The original intake weighs 38 lbs. The new one is 18 lbs. The ports are much larger. The intake looks very tall when natural aluminum but once painted it looked more like a Ford intake. The height is actually about the same as the stock intake with a 1" spacer.