Hello to all who have helped me with this project . @emerygt350 ,@TJB/914, @Superhawk996 , @ChrisFoley , @rjames , @MDTerp
I am in the middle of rebuilding my MPS and have a couple of comments and questions .
First when I opened up the unit I found the most difficult job was removing the rivets holding the two halves together.
When I removed the retainer plate to take out the old diaphragm it was in two pieces .
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I needed to take two measurements since I was replacing the stop screw , I needed to measure the the stop screw protrusion into the housing . The instruction sheet sent to me by a member had the measurements he must have made when rebuilding his MPS . His stop screw protrusion was 1.97mm and mine only measured 1.72mm.
His inner/outer screw assembly depth in the old diaphragm measured 6.51mm .
Here's one of my questions ?
when I measured mine I got two measurements depth to inner/outer screw assembly was 4.03
and depth to the washer outside the inner/outer screw assembly was 5.46mm.
Again there is a difference and since mine was never accessed before (epoxy over screw was not disturbed) is the difference in measurements ok and which measurement should I use I will try to attach a photo or two to help with my question.
this one .
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I have not touched either of these measurements yet and awaiting any help/comments.
I think it's this one to the washer on diaphragm .
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There you have it, now you know why it was a leaker. Good job! The last unit I did had a diaphragm do exactly the same thing upon disassembly.

The measurements are just to get you close . . . In the ballpark . . . Instead of being way out just randomly assembling. It will ultimately still need tuning which is why you have the tuning tools too.

Pay attention to reassembly directions - gasket placement matters. Chris’ instructions will get you there.

Thanks , I just needed some encouraging words , I will start assembly later or in the morning .

I agree the measurements just get you close when you reassemble everything. I wouldn’t worry that your numbers are off from mine. I would just reassemble back to your measurements and use the same reference points when measuring the new parts.

Well all done . I must say it was easier than I thought I was just making a bigger deal of it since this rebuild was my first . I actually found by using a heat gun to soften the epoxy it came out very easy . Even the threads cleaned up nicely with a little heat and a pick , no need for a tap to chase the threads came out nice and clean the screw removed easily . Here's a few more photos . Now for the fun part ,tuning my car to run better for my 2056 motor . More things to learn for me
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Another documented case of a completely fractured MPS diaphragm holding at least some vacuum. Amazing that it holds any vacuum at all, which affects the inductance values of the internal coils and ultimately injector pulse width.

Way to go. I mean you are disassembling the most important sensor in the system so a little worry is called for the first time you do it. I will send you some info on checking the curve.

Crazy that it could hold vacuum at all!

Mine did the same thing. It’s my belief that they don’t actually fracture into two pieces until you crack the case open.

I think it’s basically a giant stress crack but it’s not fully fractured. Thus the partial leakage.

Because there is the partial leak it basically prevents the diaphragm from moving anywhere near full travel - thus limiting further stress on the diaphragm when it’s assembled.

Then when the case is pulled open, it lets go all the way around. I can’t prove that but like you, seems to me if the whole thing was literally in two pieces it wouldn’t even hold the partial vacuum.

Well I was optimistic that my car was going to run a lot better this morning after installing the rebuilt MPS but that was not the case .I reconnected the retard to the distributor and removed that resistor I bought from AA in the CHT circuit and started the car and it would barely start , changing the timing did not make difference in the rough idling .Quite different from before I changed the diaphragm in the MPS . The car was rocking back and forth and running very rough . I first checked my plug wires and found them all intact . I then removed the distributor cap and inspected it and could see that the 4 contact points and the end of the rotor were burnt .Did not know what to think of this but figured this must be the rough running issue . I had installed a Pertronix system and removed the point/condenser several months ago so I decided to remove the pertaronix and reinstall my points /condenser. I also cleaned up the burn marks on the cap and rotor ( I installed brand new cap/rotor and plug wires after the rebuild of my motor) . I have not tried installing a new set of plugs since it was running ok yesterday .
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This did not make much change and after several hours of scratching my head on this one . I needed to take a break . Its going to be a busy weekend with Mothers day and another comitment so I may not get back. to this until next week .

You can pull the wires one at a time till you find the cylinder not firing. It also looks like your dizzy has shot bushings.

If it was rocking really bad I would say you were on two cylinders and I bet something is up with the wiring to the trigger points. Remember, it ran before you moved all kinds of wires in the passenger side of the motor.

This is going to be a tough love post.

When you encounter a problem - don’t run off like a squirrel on meth and start changing and swapping parts. You’re getting distracted and confused by all kinds of parts changes and assumptions. The random changes to timing and/or retard aren’t helping.

You should have visually checked and verified spark at each plug before jumping to conclusions and swapping from Pertronix back to points. Maybe I’m misunderstanding what led to that decision.

There is nothing going on in the distributor cap that would have changed overnight / since the MPS swap that would account for the behavior you’re describing. Could be as simple as the cap not having been properly seated or bumped during the MPS removal / install. Again I’m probably not understanding all that happened.

There is literally no telling what’s going on after all that chaos.

When you encounter the unexpected - go back to the basics. Avoid the urge to start swapping parts. Change one thing at a time. If it doesn’t help, revert to the original condition and don’t keep stacking changes.

The basics:

1) Spark. Visually observe spark at the plug. Set static timing at 7-8 degrees if the points are still in there. If you don’t know how to do this - ask and we’ll post instructions or provide a YouTube link. Avoid moving the timing around randomly. Verify you haven’t disturbed coil wiring. Test the condenser if need be - again post if you don’t know how.

2) Fuel - in this particular case (with a new and untuned MPS) I’d have stated by putting vacuum directly on the MPS and verifying the MPS connection all the way back to the ECU if necessary. I’d be verifying CHT resistance and wiring after playing with the resistor (which shouldn’t be in a late car anyway). observing plugs condition for grossly rich or lean conditions post photos. Use stating fluid if need if you think you aren’t getting fuel. Trigger points wiring as suggested by Emery. Grounds - did you knock off - disturb grounds serving injectors? Edit: did you bench test, the MPS for leakage - primary coil resistance, inductance etc on the bench before throwing it in the car?

3) Compression - don’t touch valves or anything at the moment. It certainly didn’t change due to a MPS swap or any of the other changes that were made.

Ron, here to help but at this point I’m not sure where to start - you need to get settled on what condition you want (points vs Pertronix) and how you intend to run the fuel injection (with resistor or not; I recommend without). You need to stabilize your timing settings.

You can work through this! Don’t give up. Be methodical in the approach.

I’m going to post this over here

This is another change you’re completely neglecting.

Generally speaking - you’ll find NGK and other spark plug makers recommend against anti-seize. This is because the plug needs a good ground path to the head to spark.

Anti-seize also modifies the torque spec - so the spec they give you is for no anti-seize. Torquing to their spec with lube can lead to stripping threads.

Now for reality. I use copper based anti-seize but very sparingly (not like this photo). You should get a good enough ground from contact between the plug shoulder and the head. But - - you’ve also added the CHT sender in the mix and ground path. If the CHT sender isn’t allowing a solid connection between the plug and head - ground path could be compromised.

I’m not posting this to shame you but rather to get you thinking about how many changes were introduced since it ran last and that things as simple as too much goop and/or a improperly seated CHT sensor could be causing your misfire / engine rocking that you initially described.

Note: if you don’t have a slot cut into the head to allow that CHT to seat properly, it often takes some creative bending to get that CHT down into the spark plug pocket correctly.

Examples / pictures
http://www.914world.com/bbs2/index.php?showtopic=312118

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What Hawk said.

And you just rebuilt your MPS, so it’s quite possible the rough running is it being way out of tune. After rebuilding mine and thinking I had all of the adjustment screws close to where they were before the rebuild, the car was running so rich that it barely ran and was stumbling badly.
Not saying this is the cause, it’s hard to say now given that you made multiple changes. Finding a baseline may be difficult now. Methodically check all the non-MPS changes you made.
If after that it’s still running badly, try turning just the inner screw on the MPS 1/4 to 1/2 turn clockwise to lean it out a bit and see if that makes a difference. This assumes your timing is in the ballpark.

Good luck.

Thank you Superhawk and emery ,You are correct in all you wrote I did a bit of squirreling today . I should have verified all the points you made . I basically need to pull back and start over but at this point I am beating myself up a bit as I should have known better . I will start correcting all these points next week when my head is clear and I have the time to commit to correcting my mistakes . When things went bad today I made a few bad choices . I should have asked about the CHT install since I was not well informed . I really screwed this one up today .
Thanks in advance for the questions coming next week .

Once it is all back together, remember that inner screw on the mps is a freebee. You can change that without disturbing all the other interconnected adjustments on the mps (outer and full stop interact). You can turn it in our out without worry as long as you hold the outer screw steady with Foley's tool. As rjames mentioned, once it's going again you can try leaning it out while in the car and running.

Hello @Superhawk996 @emerygt350 , I started confirming the points you have made here,
I wanted to undo all the mistakes I made on Friday so first to address why I changed the Pertronix out - 1)My brother in law thought it was a good idea,2) I read if you accidental left the ignition on it could damage the ignitor part .I don't think I have done this more than 5-10 seconds max when messing with the motor and it died after starting . Because of the burn marks I discovered on the cap and rotor I thought maybe it had been damaged . I would like to reinstall it as it eliminates the dwell setting .
Should I do this to get back to where I was ?
I tried to start the car after installing the MPS and the car would not start .
there was no vacuum on my new gauge and the car would not start,( this was my fault because I removed the gauge the night before and I forgot to connect the vacuum line ) reconnected vacuum and tried to start car again.
Car did not want to start so I retarded the timing as I had done before to get the car to start, once started I noticed the vacuum was only 13-15 inHG and was idling rough.
I tried to advanced the timing but the gauge no longer showed a high vacuum reading of 21inHg any more , no matter which way I moved my timing the vacuum stayed at 13-15inHg .

1) Spark - I checked all plug wire connections and then (not sure if this was correct) used the timing light on each plug 1-4 and checked for a pulse ( Had a pulse on all four).
Pulled cap/rotor ( it was not disturbed ) and checked ,that's when I noticed the black arcing marks on the four plug connections and on the rotor I cleaned the contact points and reinstalled the cap/rotor but I still had rough/shaky idling.
Here's where I squirreled and decided to change the Pertronix unit for points/condenser (new point and condenser set gap to .016), this made no difference.
Now for a bigger problem I think I have created for myself to correct , this is when I did my worst squirreling around.
When I tried to start car after reinstalling the distributor I did not have the distributor seated all the way as I had thought by rotating it so that it seemed properly seated . I know this because I again pulled the cap and discovered the rotor would turn telling me it was not seated properly before I turned the motor over , this is why I assume I need to get establish TDC position and reinstall the distributor . I need some guidance here before I proceed .
Since I have to pull the distributor I would like to install the pertonix back before I proceed any further .

2) Fuel- I did some checks first today and have the following new information for you .
Rechecked the coil resistance on the MPS
between pins 7-15 94.2 ohms , pins 8-10 347.1 ohms . No continuity from the MPS case to any pins . Applied vacuum to MPS and verified the same resistance valued form the coils
I did a leak down test @ 10 & 15 inHg start points ,see photo for results
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I also removed my ECU and verified good continuity from the MPS plug back to the ECU plug .
I also pulled my plugs and verified if I had a groove cut in my cylinder heads for proper seating of the CHT sensor and removed the anti-seize .
here's a photo of the plugs and groove which I have #3 .
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Distributor trigger contacts :
connection to ECU 12-22 continuity , 12-21 no continuity (I must not have had my probe in correctly .
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CHT resistance ( with the resistor removed) ECU pin 23to GND (my outside temp.71 deg) =6.28 k ohms .
I also tested the trigger point wires themselves dizzy pin 22-ECU pin 22 000.4ohms , dizzy pin21-ECU pin21 000.3 ohms , dizzy pi2 12-ECU pin 12 000.5 ohms

Don't worry about TDC, the distributor only goes in one way, it has an offset on the shaft. You can put it in wrong and clamp it down so hard it will spin but don't do that.

I would go back to the pertronix for the moment.

Did you double check your trigger points connections?

If you can get it back to where it was when you tried running it, that would be great.

Hi ,
yes I rang out the wires from the trigger points plug to the ECU plug and I have continuity on all three ( I must not have had the probe inserted correctly (I added resistance values for the individual wires for both the MPS and the trigger points .
Also checked the resistance of the CHT wire without that added resistor in circuit and it was
000.2 ohms.

I will reinstall the Pertronix back and follow up here on this post .

What about the bad bushings in my distributor you mentioned ? Can I purchase parts and replace them or do I need to look for a new distributor . If only I didn't live in California I would buy a 123 .

First on the to do list

MPS is leaking down too fast. Something not right. Did you use a light coat of grease on the gasket. Did you assemble the gasket / diaphragm in the order indicated? 1st time i did one it didn’t seal properly - didn’t grease the gasket to see what happens - it leaked.

It should be holding vacuum much longer than it is.

The other stand out is the ECU trigger points. They alternate as you rotate the engine. Did you only check them in only one position?

Whether or not I go back to Pertronix would depend on which you have. The newer version 2 & 3 supposedly has a protection built into them to prevent the ignition on burnout problem of the originals. So if I had an original - stay points. If you have one of the later 2 or 3’s I’d be fine to change back. The main downside of Pertronix is it just isn’t as easy to see it work but if you’re getting spark at the plugs - good enough.

FWIW - check spark visually. The timing light method can fool you if you have soot fouling of plugs. Just because the timing light flashes doesn’t not guarantee a spark has jumped the gap. Your plugs are looking janky but i don’t think they are the root cause of your problem. They have been too rich due to the CHT resistor and the fact that your MPS isn’t working properly.

Aren’t other guys in CA running 123’s?

Regardless - worn dizzy bushings or not - that doesn’t account for the no start issue.

Also with respect to the dizzy vs timing

Yes - start over from scratch. Assume nothing.

Find TDC on cyl #1 compression stroke. Install dizzy properly. Verify rotor position per Haynes / factory manual. Verify plug wires in proper order.

I'm not aware of any reason you can't run a 123 on your car here in California. If you are thinking it is because of the smog check, I don't think that's the case. You can correct me if you're aware of some part of the regulations that I'm not remembering. In any case, I wouldn't try switching out to the 123 until you have solved your current issue.

I don't have much to add to the advice your received so far from people with more experience than me, but do be sure to carefully check your distributor cap for a hidden crack. I couldn't tell from the picture if there was any streaking on the cap. There is some wear around the rim of the distributor cap that I can see in your picture (at 12 o'clock in the pic) that makes me a bit suspicious that the cap was moving around.

As far as putting a 123 in my California car I was told in order to pass the California smog test the car had to have all the original factory equipment that it was sold with . The biggest issue is I do not have a catalyst on my car but because my car was not sold in California I should be exempt , we will find out when I take it in for the test . I had a 73 VW bug that we rebuilt to a 1835 and when I went to get my smog test I was failed (even though the car was well below the carb standards ) because I did not have the original equipment it was sold with ,like the vacuum advance distributor ,oil bath air cleaner , something else I don't remember ,oh it was the carburetor .I had to put the old solex ,air cleaner and distributor on the car and go to a BAR station where after testing the car was now putting out more than the standard allowed but because it had all the original. equipment on it they gave me a waiver . I remember the guy doing the test was really pissed off because as he said he did not have the authority to open and inspect the motor and he knew it had a cam in it still but had to give me the waiver . I guess I can do some more investigation on the 123 but I just don't want to do anything that might cause me to fail and would hate to have to remove e it every two years for the test . I don't even want to install the Bursch I got for my car because I have the original muffler with the Cat delete pipe and plater on my air cleaner still .

I greased the paper gasket and installed it first then the diaphragm ,and next the retainer ring I did not gob a lot of grease on the gasket but covered both sides well and used wheel bearing grease as was suggested in lieu Haylomar .I removed the original rubber gasket ( it was more square than the supplied round one) that was on the electronic side and replaced it with the one supplied .
I can always open it back up and check if that does not sound correct just to double check .
I also can change the plugs with a new set I have .
I have already taken out the points and reinstalled the Pertronix , here is the box it came in .
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Not quite sure about the trigger points ( I only verified they were plugged in correctly on the dizzy and the conection to the ECU was good . I would say I checked them in one position How do I properly check them ?
How do I test the plugs properly ( I am new to this stuff so walk me through what I should do ) .
It's getting late so I will have to get back to the car tomorrow . I will wait for any new suggestions or comments .

The cap is brand new that wear was on the cap when I took it out of the box ,I assumed it was cleaned up during assembly that way . It was securely snapped into place .

I would open the MPS back up. I can post time lapse video of my MPS if necessary. It doesn’t leak down. I may have reused the OEM rubber seal - can’t remember for sure. I know from experience experience they leak if not assembled properly.

I wouldn’t worry about changing the plugs yet. Get it running better 1st. I’m old school - the way to test plugs is remove them, hook to spark plug wire, use insulated gloves or tools, hold metal part of the plug to the engine / ground, cranks the engine and watch for a bright, hot blue/white spark. Intermittent, weak yellow spark is bad news. Spark not jumping cleanly from the center electrode to the ground electrode is bad news. Seeing the spark as it jumps the gap gives you a lot of information. SAFETY NOTE: don’t do this right in the vicinity of the cylinder bore where fuel vapor may be. Fan housing is a good ground and a safe distance from cylinder opening. Better yet - disable fuel pump while doing this by pulling the pump relay.

With respect to the ECU trigger points - just rotate the engine about 1 revolution and verify both sets of trigger points are working. They alternate. One set open, once set closed. The more important thing is to be sure your electrical spade connectors from the wiring are right on the trigger points and making good contact. I doubt anything in the points themselves has changed from when it was runnning last.

Check your FI grounds.

That Pertronix box looks old, shop worn, annd doesn’t indicate igniter 2 or 3 so I’m going to assume that’s an original subject to burn out and flaky operation if ignition left on. Personally, I would stick with points for now while troubleshooting. The original Pertronix is a deeply flawed design in my opinion given that it can be damaged by leaving the ignition on. It’s a black box - you can’t see or measure what’s going on inside.

If you do the visual spark plug test and have a good strong spark with the Pertronix in place - then leave it. Just be aware of its flaws and keep the ignition off while you are doing other troubleshooting lest it go bad in the middle of the troubleshooting and cause more confusion.

I agree with hawk. The first time I rebuilt mine it leaked as well, just didn't get it back together right (I think I forgot the gasket or put it in the wrong place? Can't remember). After I put it back together right it held vacuum forever.

I appreciate your information . I figured that was how I should test the plugs but wanted confirmation . Good idea about the fuel pump ,don't want to start a fire . I unfortunately already put the Pertronix back in . Because of what I read I jump to turn off the ignition while I am in the engine bay if motors shuts off while I am messing around so I will be careful. I do carry a set of points/condenser/feeler gauge in my cars tool bag just incase,
I will recheck the trigger points I did verify the markings on the wires go to the correct terminals on the dizzy and good connection is being made . I need to reconnect the ECU and reinstall in its location today before anymore testing ,I also will use the old plugs ,I really did not want to put my new plugs in just yet until I get this problem figured out . I will need to order a new set for my tool bag .I will need to find someone to crank the motor over for me so I can test the plugs , I do not have one of those remote starter switches but that sure would make this easier because I usually only have myself for these things . I was thinking of opening up the MPS later today ( I really didn't expect to see so much leak down after replacing the diaphragm . I am almost 99% certain I replaced everything correctly in order . Paper gasket went in first then diaphragm then metal ring . The only suspect to me was using the new round rubber gasket over the old square edged gasket .The small ring was replaced on the big screw as shown in the diagram. Should I reapply more bearing grease to the paper gasket? I wouldn't think the settings I took and used for reassembly would cause a leak ? I will update this post as soon as I can get to these new things to do .

Ron got that Pertronix from me, and yes it is older. It sat in a box on my shelf for at least 10 years.... If it is a worry for you Ron I'm happy to refund your money and you can simply trash the Pertronix.

I went down the rabbit hole and I think you are correct about the 123 and the smog check. Of course everything depends upon who is doing the inspection. I believe the 123 would fall under the category of performance distributors, and these would require that the company submit it to the CARB for certification that it does not make the car run dirtier than the OE distributor. An exemption would then be issued. I couldn't find any documentation of this having been done.

Remote stater switch is about $15 and priceless in operation - eliminates the need for that helper.

Yeah - maybe a bit more grease on the paper gasket. But no means should it be slobbed all over but a dry gasket will leak. Tried it. It definitely leaked.

I also put a touch of silicone grease on the o-ring. I don’t recall that being in the directions but that’s what I do with almost any o-ring.

https://www.youtube.com/watch?v=Z0n2aTFRMiI?si=W8rg02X2Kwp4r_54


I cut this off at 1/2 hour simply because it doesn’t move.

Keep going on it until you get a good seal on the MPS

There is an art (and likely some luck) in getting the MPS to fully seal, even when you put things back together correctly. One thing that I've had good luck with is tightening each of the screws (or nuts/bolts) that replaced the rivets a little at a time before moving to the opposite one, similarly to how you would tighten lug nuts so that you tighten the whole thing down as evenly as possible.

I checked the trigger points and they are switching between 12 &21 ,12&22 with good continuity back to the ECU . I lightly rubbed grease on both sides of the paper gasket so I will take it all apart again and reddit .I did tighten the screws opposite of each other like lug nuts but I will just have to open it and try it again ,I will add silicone to the large ring , to get to the little one I will have to redo the adjustments . Not sure if I want to mess with that but if still leaking I will redo everything .Is the fuel pump relay the large rectangle silver one ? Still waiting on neighbor to test the plugs . I think I read somewhere what is needed and how to connect a remote starter ,this would be handy .

It's not a problem fiacra ,
I don't want any money back . Everything with this car is a learning experience for me . I will just be extra diligent when outside of the car tuning it . If I was to eventually pass a smog test I could then install the 123 but would have to remove it every two years or find a guy as everyone tells me that looks the other way . Hopefully Jay Leno's law passes and I won't have to worry about the smog check any more . I know there is a lot of controversy about that law . I could also buy a newer version of the Pertronix if I wanted to but I would rather put that money into a 123 but first order is to get my car sorted out and pass the smog test .I want to drive my car to my first WCR in June .

Good luck with this, my MPS is leaking too, watching and learning.

Just a heads up, there are other places the MPS cases may leak besides the gasketed locations. If vacuum loss still occurs investigate/repair these also. Methods I have used:

-Case to outer plastic 4-pole harness connector interface. Run a line of superglue around this joint.
-Check valve at internal port, back of case. Not much to repair here, but replace the check valve if you have a donor MPS case.
-Center-most adjustable screw (inner screw) to outer screw at the center of the diaphragm fixture. Add a small dollop of grease over the slotted screw head to seal the threads, grease will get sucked into the threaded joint if there is a vacuum leak.
-Joint interface between the pleated diaphragm and its center threaded pressed on fixture. Run a line of superglue around this joint.

dbl dbl.

I wouldn't advise you do that. Unfortunately those people are out there, and I'm sure you could find a shop that would do it, but I'd like to think you are a more ethical person than that. I know you can do this the right way.

The "large rectangular box" on the relay board is the voltage regulator. Here's a link to a picture of the relay board with the relays labeled.

http://www.914world.com/specs/SirAndyCarbFuelPumpRelay.php

And here's a link to a video explaining the relay board.

https://www.youtube.com/watch?v=YLgQxpNHzIU

A remote starter switch is cheap, easy to get, easy to use, and invaluable when adjusting the valves.

[quote name='SVG223' post='3205335' date='May 13 2025, 05:18 PM']
Good luck with this, my MPS is leaking too, watching and learning.

Well I opened my MPS and found that the order in which I assembled was wrong . I installed the spacer ring over the part load stop which was wrong .I corrected this installing 1st the paper gasket(regreased) then the diaphragm followed by the spacer ring and the part load stop plate. Put it back to gather and tested and it still has a slow leak. I followed Jeff's advice and sealed the plug connection and then the area around the diaphragm center ring . I will put it back together later and test again and update .
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I switched from a round o-ring to square in my kits a long time ago. Use grease on the round one, for sure.

I think that is exactly what I did the first time too. While you have it out, map the curve. I sent you some emails describing how...

Hi Chris,
I am still having leak down issues .It's a lot better but not ideal . How about if I put the old square gasket back in ? What's your opinion on that ?
I did all the things Jeff recommended but still had significant leaking .
I figured if the connection plug could be leaking at the base why not through the pins so I covered the plug with Gorilla duct tape .Here are my results after that last fix .
Next I am going to go around the case halves with electrical tape and put the square ring back in . I will update soon .
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Hi emery,
Thanks for the curve, I will check my email shortly .Definitely will be easier when out of the car .
Ron

Although no leak is best. That leak is pretty slow so if it can't get any better I bet you will be fine.

Get rid of the adapters

Go straight from vacuum pump to MPS

Heat / stretch tubing as necessary to avoid the adapters which are all possible leak paths then retest

Mine takes 45 seconds to leak from 10 in/hg to 5 in/hg and runs lean with 22 inches of idle vacuum. I added fuel pressure and 270 ohms of resistance to the cht. It runs strong with a smooth idle at 900 rpm. It craps out above 4500 rpm, I'm probably going to send in my injectors to be cleaned, and due for a valve adjustment. Ideally, it shouldn't leak, but what you've got now should work fine. Does anyone use Permatex Form-A-Gasket No. 2 Sealant on the mps?

There are some things you can do with the mps to ensure it's getting the extra goodness at full throttle but I am not sure that is your problem. Do you have the Foley kit in your mps?

@Superhawk996 I removed the connectors and my leak down numbers are still about the same . I am at a loss . All this for nothing . I am thinking I should just by a new MPS . I know where might be able to get one but its going to be expensive .