Pinto bucking / no power in the corners

[redcar9]

Finally got out for more than just 8 minutes. Still chasing problems.

The car will have no power when any steering input is applied. The keyhole (turn 5) shows this, braking, downhill and a right hand turn. I'm full throttle on the car and there is no acceleration until a few seconds on the back straight. The car also has no power in 3rd gear, I top out at 107-111mph back straight of mid-ohio. I have been told I should be able to hit 130mph.

1. Carb was looked at by Ivey, they suggested increase the level of the in the bowl, this helped a little.
2. spark gap was about 0.036" (next time I'm putting it at 0.026")
3. The valve lash on both intake/exhaust was ~0.016" measured cold. (going to change to the recommended 0.008 and 0.01")
4. Cold compression with throttle open and all 4 plugs removed.

• #1 178psi
• #2 147psi
• #3 155psi
• #4 155psi

Aim data
https://www.dropbox.com/scl/fi/0u0sd...=rkhdpoj2&dl=0


https://youtu.be/13VgajdP_UM?si=2WcyWB9qmJTzG12t

[2BWise]

Have you checked the timing?

[Purple Frog]

What 2B said. Timing.
Plus what gear set is in the car? What rpm at 110?
With the pinto in race mode you should never get below 5500 rpm.
If you are trying to drive out of T5 at 4500 rpm, that would be the problem.
Back in 2005 if you were DaveW in a pinto car at M-O you would be running a 90 mph 1st gear, 108 mph 2nd gear, 122 mph 3rd gear, and 138mph 4th gear. (all speeds based on reading at 6900 rpm)

[Purple Frog]

From 2010 post:

OK. I called QS and asked what they do to set the valves cold.

When they set up the head on the bench, for the intakes, they use 0.010 on cylinders 1-3, and 0.009 on cyl # 4. For the exhausts they use 0.013 for # 1, and 0.012 for the rest. They might have to adjust one or two slightly hot after they're run in, but that gives them the desired 0.008 intake and 0.010 exhaust (hot).
So the 0.002 extra clearance, as I said before, seems about right for cold valve adjustments of a head mounted on a block.

[Purple Frog]

Carb issues:
Is it dumping fuel at idle (too high float level) or during cornering (need to solder shut the secondary idle jet)? Or is it some other problem?


Carb Jets:
The secondaries should be mechanically operated. This means that any time you are at full throttle (and this will be 95% of the time), both the primary and secondary will be open. If you are seeing a discontinuity in the EGT's, that may be due to the auxiliary enrichment tubes (put in by various engine builders to modify the fuel distribution) starting their flow with a slight delay - this is normal.


The main jets are located in the bottom of the float bowl. To change them you remove the top of the carb (6 screws) -- if you are careful not to tear the gasket, it can be reused. You will probably have different jets for the primary & secondary venturi -- so be careful to note what size is currently used for each one. A "one jet leaner" usually mean a differnence of 5 (i.e. change a 175 to a 170 - smaller numbers are leaner).

Your carb also has air corrector jets (aka A/C) -- you also remove the carb top to access these -- but they are located on the upward face of the carb body. Again, primary and secondary values may be different. The air correctors adjust the mixture just at the high flows (i.e. high RPMs) -- three steps of A/C jets is about the same as one step of main jets. A larger A/C jet will make the mixture leaner, and a smaller one will make it richer.

Finally, you will find idle jets on the side of the carbs in the main body, just below the top. You unscrew the holder, and the jet sits in that. Watch out not to lose the rubber o-ring under the jet holder. Idle jets are hardly ever changed, but you should pull them out to make sure a piece of debris hasn't clogged the very small orifice.

The mixture screw located near the base of the carb will adjust the mixture at idle. With the engine running at idle (usually 900 - 1000 RPMs), screw it in until the engine starts to run rough, then back it out again until the engine again begins to sound a bit rough -- at that point, screw it back in 1/4 to 1/2 turn and you're all set -- a smooth running engine.

DaveW’s jets in 2006 were:

JET PRI SEC
AIR 200 140
FUEL 135 165
(FOR AVGAS, ~55F)

[Purple Frog]

Check cam timing, you could have had a rock get in the belt and it skipped a tooth....

[Purple Frog]

A well prepared pinto race carb will do this: At idle in the paddock if you rapidly go to wide open throttle it should "stagger" a bit before it revs up. (per DaveW in 2007)

[Steve Demeter]

You mentioned that it acts up with any steering input.

I would also check the pick up in the fuel cell to make sure it is in the right position. Lateral forces could be uncovering it.

This is a long shot I know

[DanW]

You mentioned that it acts up with any steering input.

I would also check the pick up in the fuel cell to make sure it is in the right position. Lateral forces could be uncovering it.

This is a long shot I know

Or there is fuel cell foam debris blocking the pickup.

[redcar9]

What 2B said. Timing.
Plus what gear set is in the car? What rpm at 110?
With the pinto in race mode you should never get below 5500 rpm.
If you are trying to drive out of T5 at 4500 rpm, that would be the problem.
Back in 2005 if you were DaveW in a pinto car at M-O you would be running a 90 mph 1st gear, 108 mph 2nd gear, 122 mph 3rd gear, and 138mph 4th gear. (all speeds based on reading at 6900 rpm)

Thanks for all of this info, let me look at all of this.

I think the timing was around 35 or so, I had issues starting when it was at 37.
This was measured at 4000rpm

[Purple Frog]

All the pintos I've been around start very easy... like they just jump to life immediately, no long cranking. Hit the starter button... boom.

I suspect something is out of spec. A lot of what you write sounds like carb.

There were some older pinto versions, usually built by Dixon, that had distributors locked without any advance. To start them cold one sometimes would have to set them back to 10 degrees to be able start and get warmed up. Once warm then you advanced it to the race spec. It was to me a PIA.

Does this car have an MSD ignition? I've seen them go wonky.

[Rick Kirchner]

just for grins, check your fuel pressure

[Joefisherff]

just for grins, check your fuel pressure

I'm with Rick, Rex Gunning chased an issue and determined that some of the fuel pumps are designated as a higher pressure pump versus the stock pump (which could not keep up with the fuel demand of a higher performance engine, he tried an electric pump and the issue was solved.

[roadracer]

Many good suggestions and checking timing with a light would be a good step if not already done. Pertronix ignition? They will fail and can appear to be a fuel starvation issue. Problems always end up being something simple... but hard to find.

There is a small fuel filter inside the carburetor on the underside of the fuel inlet. It has a 19mm brass cap. The filter is a fine mesh and worth checking. There should be a fuel filter between the fuel cell and the fuel pump and I'm sure you've checked it.

Float level has been mentioned but important to check it after the engine has been turned over on the starter and then the fuel line to the carburetor disconnected. This step guarantees the fuel pump will not be squirting more fuel into the carb when the top is removed. Also a good time to check fuel pressure as it is typically 3-4 lbs, not 10+ as mentioned above. Fuel level in the float bowl should be 3/4 inches. The needle valve has a taper and it should not have a ridge on it that could bind up.

The fuel float (brass?) can be an issue if it is hitting the side of the carb body, so look for any bright spots where it may be touching.
Also check the float to be sure it does not have a leak by giving it a shake. The float "drop" or free-play is important and it should be 1/4 inch. With the carb top on its side and the float pivot pin up and down, the seam on the float opposite the pivot should wiggle back and forth about 1/4 inch. The brass float has a small tab on the side to restrict movement and typically they are not adjusted properly.

Underneath the air correction jets are the emulsion tubes. Using a small easy-out or length of wire they can be lifted out, tapped on a hard surface to dislodge any foreign bits. Doing one at a time makes it easier to avoid mixing up the parts. They are easy to overlook.
Lastly, both carb venturis should be tight in the bore.
Good luck with this!

[redcar9]

just for grins, check your fuel pressure

I'm working down the list of everyone's suggestions here is this one.

Started it up ran for a short bit, then ~1500rpm idle to full throttle.

https://youtube.com/shorts/DEW_wW31CD8?feature=share

[redcar9]

Here is a little update.

Fixed the spark plug gap down to 0.026"
The valve lash was all over the place #1 had intake at 0.04 and similar exhaust. I used the QuickSilver engine suggestions and only 2 of the 8 valves were correct.

This did improve and even out the compression across all cylinders. Taken with full throttle.

[redcar9]

delete

[redcar9]

All the pintos I've been around start very easy... like they just jump to life immediately, no long cranking. Hit the starter button... boom.

I suspect something is out of spec. A lot of what you write sounds like carb.

There were some older pinto versions, usually built by Dixon, that had distributors locked without any advance. To start them cold one sometimes would have to set them back to 10 degrees to be able start and get warmed up. Once warm then you advanced it to the race spec. It was to me a PIA.

Does this car have an MSD ignition? I've seen them go wonky.

After adjusting the idle mixer screw and the idle screw. It starts so much better! It now starts instantly just like you said.

Got the idle RPM 900-1050 or so much better than my 1400-1600 from before.

Here is the distributor, it does move some.
https://youtu.be/8twvmAp_L9E

I replaced all of the ignition last year chasing problems due to clogged tubes in the carb. I had Ivey redo the carb.
The ignition box is an MSD 6425
https://www.summitracing.com/parts/m...xoCqc8QAvD_BwE

The Jets...
Pri. Sec.
Fuel 160 165
Air 165 160

Jet picture.
https://www.dropbox.com/scl/fi/4yeo1...=4e1vq90g&dl=0


I put the timing at 37 degrees, but when I ran the rpms up beyond the 4k test point. I noticed around 6k or so the timing mark shifted.
https://www.dropbox.com/scl/fi/r6m71...=z8yq10cs&dl=0

[redcar9]

I'm with Rick, Rex Gunning chased an issue and determined that some of the fuel pumps are designated as a higher pressure pump versus the stock pump (which could not keep up with the fuel demand of a higher performance engine, he tried an electric pump and the issue was solved.

The test I did at full throttle the gauge was showing 2PSI, looks like that might be part of my issue? It needs 4PSI?
What electric do you recommend? I need to then add a regulator to cap it at 4PSI right?

[Purple Frog]

I raced for years in pinto motors with mechanical fuel pumps. Just saying... You may just need a fuel pump.

I know this is going sound complicated, but... The length of the pushrod that activates the pump is critical to get the correct amount of action. Some engines run the stock insulator block between the engine block and the pump. But... Some chassis required that insulator to be removed so that the pump would fit inside the chassis. In those cases the pushrod was cut down the amount of the thickness of the block being removed.

If by chance you have a "short rod" in a long rod application that could be the problem.

OBTW, I don't know the spec for how long the throw is supposed to be to operate the pump correctly. Any of the good engine builders should know. It can be measured by manually turning the engine over.

[Steve Davis]

...
I put the timing at 37 degrees, but when I ran the rpms up beyond the 4k test point. I noticed around 6k or so the timing mark shifted.
https://www.dropbox.com/scl/fi/r6m71...=z8yq10cs&dl=0

Sounds like you are making serious PROGRESS with this thing now.
That 'picture' of the timing at 6k is somewhat 'suspect'. For more info, we need a VIDEO of that if possible. That LOOKS LIKE a *LOT* of variation from the 'proper' location. There is a SPRING at the bottom of the dist drive (the bottom of the disto that fits down against (close to) the cam shaft). If that spring is broken or missing.. or just too weak, the dist drive can bounce up/down when the engine runs.. causing excessive variation of the timing. Only way to be sure would be to pull the disto.. if you do that, be VERY careful and note EXACTLY where the rotor is pointing as it comes out - it will turn a bit as it comes out.. and needs to 'turn back in' as is goes back in. Simplest to make sure the engine it at TDC before you start and note the exact 'pointing' of the rotor. Then make sure you get it back to that same point when the reinstall is complete (don't move the engine with the disto OUT!). That might be a bit much for you to take on, so skip all this if you don't feel comfortable doing it. Others might have better input - my engines are all VW FV), but pretty sure the Pinto is exactly the same.

Also 6k is a bit high to be expecting things to remain 'calm' in that area. If the timing looks good and stable from ~3k to ~5k, it's probably fine. Too much vibration above 5k... especially if it's 'breaking up' at high RPM. In your short video of the fuel press you didn't spend ANY 'time' at the high RPM end.. so the indication never had a chance to stabilize .. a lot of vibration there too.. no to mention bouncing around on the engine like that. Probably get a much better reading with a long 'pipe' that could keep the gauge itself not 'sitting on' the engine. You don't need to stabilize the engine rpm way up at 6k - take it to 4k stable and read .. then take it to 5k and read again.. then maybe 5.5k.. watch for a drop in press as RPM goes up.

Keep at it and pretty soon you should have it working like it should. Don't forget that 'on carb' filter as well as any other filter that's in the fuel feed line. Found a friend's 'pre filter' just ahead of the carb totally crapped up with junk.. from not having been cleaned in several years of racing. He'd been complaining of 'high speed miss' for 2 seasons....

His Purpleness has been giving you outstanding info. He'll get you straight!

Steve, FV80

[redcar9]

Many good suggestions and checking timing with a light would be a good step if not already done. Pertronix ignition? They will fail and can appear to be a fuel starvation issue. Problems always end up being something simple... but hard to find.

There is a small fuel filter inside the carburetor on the underside of the fuel inlet. It has a 19mm brass cap. The filter is a fine mesh and worth checking. There should be a fuel filter between the fuel cell and the fuel pump and I'm sure you've checked it.

Float level has been mentioned but important to check it after the engine has been turned over on the starter and then the fuel line to the carburetor disconnected. This step guarantees the fuel pump will not be squirting more fuel into the carb when the top is removed. Also a good time to check fuel pressure as it is typically 3-4 lbs, not 10+ as mentioned above. Fuel level in the float bowl should be 3/4 inches. The needle valve has a taper and it should not have a ridge on it that could bind up.

The fuel float (brass?) can be an issue if it is hitting the side of the carb body, so look for any bright spots where it may be touching.
Also check the float to be sure it does not have a leak by giving it a shake. The float "drop" or free-play is important and it should be 1/4 inch. With the carb top on its side and the float pivot pin up and down, the seam on the float opposite the pivot should wiggle back and forth about 1/4 inch. The brass float has a small tab on the side to restrict movement and typically they are not adjusted properly.

Underneath the air correction jets are the emulsion tubes. Using a small easy-out or length of wire they can be lifted out, tapped on a hard surface to dislodge any foreign bits. Doing one at a time makes it easier to avoid mixing up the parts. They are easy to overlook.
Lastly, both carb venturis should be tight in the bore.
Good luck with this!

Thanks for all of this help!

It's an MSD Ignition box.

I didn't realize there was a filter in the carburetor, it did have some dirt I ordered a replacement. Nope this car didn't have a filter between the fuel cell and pump. Ordering that as well.

Yes, the fuel float is brass and it was low. Jay from Ivey gave me that help at the track and I increased it. He said 1/8" of an inch or so up the back wall above the radius.

Take a look at my video of the fuel pressure I think this is also an issue 2psi at full throttle.

Back to that brass float, it was rubbing on the bottom. It had nice play in both directions and we did adjust this to increase fuel level. No leaks in the brass float.
So this means I still don't have enough fuel in the bowl?
https://www.dropbox.com/scl/fi/rv1pf...=kydqydw2&dl=0
https://www.dropbox.com/scl/fi/dyl2a...=2i4xs083&dl=0


I tried to remove the emulsion tubes, but they were stuck. I will have to get another tool to remove them. All the other items you said to check were good.

Here is the engine running now.

https://youtu.be/mti28QOSEik

[redcar9]

I raced for years in pinto motors with mechanical fuel pumps. Just saying... You may just need a fuel pump.

I know this is going sound complicated, but... The length of the pushrod that activates the pump is critical to get the correct amount of action. Some engines run the stock insulator block between the engine block and the pump. But... Some chassis required that insulator to be removed so that the pump would fit inside the chassis. In those cases the pushrod was cut down the amount of the thickness of the block being removed.

If by chance you have a "short rod" in a long rod application that could be the problem.

OBTW, I don't know the spec for how long the throw is supposed to be to operate the pump correctly. Any of the good engine builders should know. It can be measured by manually turning the engine over.

https://www.apexspeed.com/forums/sho...into-fuel-pump

It had the 0.25" spacer, but the metal push rod that actuates the fuel pump was a little short and worn looking 1.97"
Just going to replace both as I want to dyno tune the car and that's expensive.

[redcar9]

Sounds like you are making serious PROGRESS with this thing now.
That 'picture' of the timing at 6k is somewhat 'suspect'. For more info, we need a VIDEO of that if possible. That LOOKS LIKE a *LOT* of variation from the 'proper' location. There is a SPRING at the bottom of the dist drive (the bottom of the disto that fits down against (close to) the cam shaft). If that spring is broken or missing.. or just too weak, the dist drive can bounce up/down when the engine runs.. causing excessive variation of the timing. Only way to be sure would be to pull the disto.. if you do that, be VERY careful and note EXACTLY where the rotor is pointing as it comes out - it will turn a bit as it comes out.. and needs to 'turn back in' as is goes back in. Simplest to make sure the engine it at TDC before you start and note the exact 'pointing' of the rotor. Then make sure you get it back to that same point when the reinstall is complete (don't move the engine with the disto OUT!). That might be a bit much for you to take on, so skip all this if you don't feel comfortable doing it. Others might have better input - my engines are all VW FV), but pretty sure the Pinto is exactly the same.

Also 6k is a bit high to be expecting things to remain 'calm' in that area. If the timing looks good and stable from ~3k to ~5k, it's probably fine. Too much vibration above 5k... especially if it's 'breaking up' at high RPM. In your short video of the fuel press you didn't spend ANY 'time' at the high RPM end.. so the indication never had a chance to stabilize .. a lot of vibration there too.. no to mention bouncing around on the engine like that. Probably get a much better reading with a long 'pipe' that could keep the gauge itself not 'sitting on' the engine. You don't need to stabilize the engine rpm way up at 6k - take it to 4k stable and read .. then take it to 5k and read again.. then maybe 5.5k.. watch for a drop in press as RPM goes up.

Keep at it and pretty soon you should have it working like it should. Don't forget that 'on carb' filter as well as any other filter that's in the fuel feed line. Found a friend's 'pre filter' just ahead of the carb totally crapped up with junk.. from not having been cleaned in several years of racing. He'd been complaining of 'high speed miss' for 2 seasons....

His Purpleness has been giving you outstanding info. He'll get you straight!

Steve, FV80

Hi Steve!
Yes, Purple Frog is helping so much. I didn't know what to search to find that data. Thanks Purple!!!

Lots of info thanks! I just marked the distributor body and pulled it, I know I will have to find TDC and do timing over again. Grabbing the bottom gear of the distributor and turning the rotor it does have a spring effect, but feels a little crunchy.

There is NO spring between the bottom of the distributor gear and the engine. Should there be one there??

https://www.dropbox.com/scl/fi/jb5kl...=t4u8558m&dl=0
https://www.dropbox.com/scl/fi/ko4xa...=3ydmrh3h&dl=0

Yes, the timing mark was okay 3k-4.5k or so, but as it got higher it becomes jumpy. I was smooth on the throttle trying to hold and let it stabilize on an RPM. This would explain the erratic RPM and the car jumping/ no power when I was on the track.

Fuel: The fuel pump top bolt was finger tight and it's an older ford made in England pump. I agree I didn't wait long enough and I should have vibration isolated the gauge to measure fuel pressure and let it try to stabilize. What I saw not in the video was sustained full throttle caused the pressure to drop to 2PSI and never recover. At this point I will just replace the pump worst case I have a spare pump. Going to order one from pegasusracing.com

Thanks for all of this help everyone!

[redcar9]

Found yet another possible explanation to the issue of it having jumping RPMs and no power in the corners.

https://www.pegasusautoracing.com/pr....asp?RecID=226

The car is running a MSD blaster 2 is oil filled and it seems that the Pertronix Flame-Thrower II 12V Ignition Coil is epoxy filled.
This explains a lot! I actually understand electricity. haha!

I'm considering going with the Pentronix coil and this distributor.https://www.pegasusautoracing.com/pr...sp?RecID=30147


What ignition box should I be running? I currently have a very large MSD 6AL PN 6425

[Purple Frog]

I had issues with MSD over the years, so i converted all my engines to Pertronix. Happily ever after. YMMV

[BeerBudgetRacing]

I had the Crane/Fast Fireball Xr3000 setup with the optical trigger. Probably in service for over 10 years. Zero issues.

[Steve Davis]

Found yet another possible explanation to the issue of it having jumping RPMs and no power in the corners.

https://www.pegasusautoracing.com/pr....asp?RecID=226

The car is running a MSD blaster 2 is oil filled and it seems that the Pertronix Flame-Thrower II 12V Ignition Coil is epoxy filled.
This explains a lot! I actually understand electricity. haha!

I'm considering going with the Pentronix coil and this distributor.https://www.pegasusautoracing.com/pr...sp?RecID=30147


What ignition box should I be running? I currently have a very large MSD 6AL PN 6425

The BIG issue with the Pertronics ignition modules is that they have (at least) 2 versions. A 'standard' older module Pertronics module REQUIRES a primary resistance (coil primary) of something over 3 ohms.. Some of these newer 'hotrod' (flame thrower type - probably like your MSD) have resistance down close to ONE OHM.. They will burn out the standard Pertronix in a hot second... or damage it significantly. I have no idea what an MSD would do to it. Pertronics also has a 'more robust' version to handle the low ohm (high current) coils, but it costs about 3 or 4 times more. There is probably a way to tell which you have.. other than when it burns out, but I don't know what it is. If the whole system is working OK, you are mostly likely fine, but be careful changing things.. make sure that the total ignition system matches it's requirements.

I agree with Purple. Your Pinto has no need for an MSD. It's just something else to burn up and leave you stranded. I DO use pertronics (or equivalent) in my distos, but I make sure I have a coil with a reasonable ohmage resistance. And those hi falootin' jobs do NOT. I learned all this the HARD way . Also don't EVER leave your ignition switch on without the engine running for more than a few seconds - not ONE second, but no more than 30 worst case. Some Times the Pertronics will survive .. most of the time - like if you forget it and find it later, it will be TOAST!

OH.. after looking at your removed disto, I don't think it has a spring.. someone here that KNOWS, confirm that. I base my thought here on the GEAR that on the bottom shaft.. the Vee gear is all the way at the bottom instead of 'alongside' the shaft. At least, that's what I THINK I remember....

Steve, FV80

[redcar9]

I had issues with MSD over the years, so i converted all my engines to Pertronix. Happily ever after. YMMV

Which ignition box are you using?

[redcar9]

I had the Crane/Fast Fireball Xr3000 setup with the optical trigger. Probably in service for over 10 years. Zero issues.

Interesting, I didn't realize they were using optical pickup to do location.
Can you set a rev limiter with this box?

[Rick Kirchner]

The crane fireball was one of the few setups that actually worked.

But all you really need is a pertronix or a powerspark unit, and a blue coil. Its not rocket science.

[kea]

The test I did at full throttle the gauge was showing 2PSI, looks like that might be part of my issue? It needs 4PSI?
What electric do you recommend? I need to then add a regulator to cap it at 4PSI right?

Weber Carbs are designed with # 3.5 Max fuel pressure, not 4
At full throttle, 2PSI (as long as the fuel flow is OK) is fine.

[jrh3]

I had Pinto power problems with a very worn throttle shaft and carb. Easy enough to check. Pegasus bearings helped a bunch.

[BeerBudgetRacing]

Interesting, I didn't realize they were using optical pickup to do location.
Can you set a rev limiter with this box?

It's been a few years and I never messed with it at all, so I'm not certain.

[Joefisherff]

The test I did at full throttle the gauge was showing 2PSI, looks like that might be part of my issue? It needs 4PSI?
What electric do you recommend? I need to then add a regulator to cap it at 4PSI right?

Something like this:

https://www.pegasusautoracing.com/pr...asp?RecID=8440

I would think you would want 4PSI consistently to keep the bowls full.

[Rick Kirchner]

Something like this:

https://www.pegasusautoracing.com/pr...asp?RecID=8440

I would think you would want 4PSI consistently to keep the bowls full.

But get the plastic ones. The pinto vibrations will break the ears off the metal ones in a few seasons if you mount it whee the mechanical pump goes.

[redcar9]

The BIG issue with the Pertronics ignition modules is that they have (at least) 2 versions. A 'standard' older module Pertronics module REQUIRES a primary resistance (coil primary) of something over 3 ohms.. Some of these newer 'hotrod' (flame thrower type - probably like your MSD) have resistance down close to ONE OHM.. They will burn out the standard Pertronix in a hot second... or damage it significantly. I have no idea what an MSD would do to it. Pertronics also has a 'more robust' version to handle the low ohm (high current) coils, but it costs about 3 or 4 times more. There is probably a way to tell which you have.. other than when it burns out, but I don't know what it is. If the whole system is working OK, you are mostly likely fine, but be careful changing things.. make sure that the total ignition system matches it's requirements.

I agree with Purple. Your Pinto has no need for an MSD. It's just something else to burn up and leave you stranded. I DO use pertronics (or equivalent) in my distos, but I make sure I have a coil with a reasonable ohmage resistance. And those hi falootin' jobs do NOT. I learned all this the HARD way . Also don't EVER leave your ignition switch on without the engine running for more than a few seconds - not ONE second, but no more than 30 worst case. Some Times the Pertronics will survive .. most of the time - like if you forget it and find it later, it will be TOAST!

OH.. after looking at your removed disto, I don't think it has a spring.. someone here that KNOWS, confirm that. I base my thought here on the GEAR that on the bottom shaft.. the Vee gear is all the way at the bottom instead of 'alongside' the shaft. At least, that's what I THINK I remember....

Steve, FV80

Thanks for this info Steve. I called Pertronics and they knew a ton of stuff!
I measured the resistance of my MSD oil based coil at 0.8ohm.

What they recommend was this.
PerTronix 600 rev limit box so it will output a signal to the AIM EVO 4 data logger.
PerTronix 45111 Flame-Thrower II Coil 45,000 Volt 0.6 ohm Black Epoxy
PERTRONIX D192400 DISTRIBUTOR w/ Ignitor I installed

Yes, he said if you leave the ignition on (engine not running) for more than 2 min it will burn the Ignitor I inside of the distributor.
He said that the Ignitor II can have dwell problems around the 2800-3500 or so RPM. Which would present like the issues that I was having.

Additional he told me to confirm the resistance between the battery negative terminal and the base plate of the distributor. It should be 0.2Ohms. Mine was reading 30ohms!!!

Going to order these parts and give it a shot. I will post the dyno tune results once this is done.

[Rick Kirchner]

Thanks for this info Steve. I called Pertronics and they knew a ton of stuff!
I measured the resistance of my MSD oil based coil at 0.8ohm.

What they recommend was this.
PerTronix 600 rev limit box so it will output a signal to the AIM EVO 4 data logger.
PerTronix 45111 Flame-Thrower II Coil 45,000 Volt 0.6 ohm Black Epoxy
PERTRONIX D192400 DISTRIBUTOR w/ Ignitor I installed

Yes, he said if you leave the ignition on (engine not running) for more than 2 min it will burn the Ignitor I inside of the distributor.
He said that the Ignitor II can have dwell problems around the 2800-3500 or so RPM. Which would present like the issues that I was having.

Additional he told me to confirm the resistance between the battery negative terminal and the base plate of the distributor. It should be 0.2Ohms. Mine was reading 30ohms!!!

Going to order these parts and give it a shot. I will post the dyno tune results once this is done.

I've had a couple of different rev limiters. Nothing but trouble.

And I'd say, you really don't need one if you build a good shift linkage with helicopter joints. All the rev limiter will do is protect you from a missed gear, but not the other, even more bad scenario - the 3-1 shift going for 4th. For that, you need a good linkage.

AIM makes an amp to isolate the dash/logger from high voltage spikes. Don't know if there's an improved version, the ones I have die if you let the battery voltage drop too far when cranking. I fixed that with a switch and a dedicated protection circuit (big-ass capacitor and a zener diode)

[chrisw52]

Interesting, I didn't realize they were using optical pickup to do location.
Can you set a rev limiter with this box?

There is no rev limiter with the Fast XR3000. I use a MSD soft touch rev limiter https://www.summitracing.com/parts/msd-8728.
https://www.summitracing.com/parts/fst-3000-0226

This setup has worked for me since 2016

[roadracer]

Pertronix makes some fine ignition equipment for road cars. The epoxy-filled coils are excellent. For some reason they may have switched to an off-shore supplier as the quality of the ignition parts has changed. Whatever you have may work for a while. Heat and vibration are the enemy of ignition reliability.

The Crane/FAST ignition systems(optical sensor) have been very reliable and feature a small separate ignition box, unlike the Pertronix unit which fits inside the distributor cap.

Ask the engine buillders for their recommendation as they know what works and will stay working.
Good luck with this.