14point7 Spartan 2 install, Holley 4150 tuning, & exhaustcapades

You ever have one of those aha moments when you realize you done f'd up? Yeah, I woke up with that this morning. Guess who apparently thought he was timing a SBC? Yep, this guy. :suicide: Kinda goes along with my earlier post about not realizing how much you DON'T know or have forgotten. SO...... I'm going to Harbor Freight this morning and picking up a new timing light since the plug lead on my old one ended up vibrating down and resting on the #5 header tube and burned through the sheathing. :bang: It's the spring type and the spring's been worn out for a while and doesn't really grip the plug anymore anyway. Seems like a good reason for an upgrade.

All in all it was a very productive day that day!! (I hope my sarcasm is noticeable)

On a positive note, the timing marks on the damper should be right, so installing a timing tape should be a breeze. And if it doesn't stick for some reason I should be good since I'll have factory marks anyway.
 
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You ever have one of those aha moments when you realize you done f'd up? Yeah, I woke up with that this morning. Guess who apparently thought he was timing a SBC? Yep, this guy. :suicide: Kinda goes along with my earlier post about not realizing how much you DON'T know or have forgotten. SO...... I'm going to Harbor Freight this morning and picking up a new timing light since the plug lead on my old one ended up vibrating down and resting on the #5 header tube and burned through the sheathing. :bang: It's the spring type and the spring's been worn out for a while and doesn't really grip the plug anymore anyway. Seems like a good reason for an upgrade.

All in all it was a very productive day that day!! (I hope my sarcasm is noticeable)

On a positive note, the timing marks on the damper should be right, so installing a timing tape should be a breeze. And if it doesn't stick for some reason I should be good since I'll have factory marks anyway.
Thing is... If it wasn't for the marks on the balancer, you COULD just time it like an SBC. They actually share the same firing order, they're just numbered differently.

Don't buy HF's cheapest timing light, go at least one step up. I've had single-AAA keychain lights that were brighter than the cheapie.
 
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This one is the only one they had in store as well as the only one online.


I picked it up and already messed with the car. It is now confirmed, it is at 14 degrees BTC as far as the stock timing marks go. Vacuum was still around 14 inches and I played with the idle adjustment screws a little afterwards. A/F meter now reads between 14.3-15.3. After all of that, I revved it up to around 3k RPMs in neutral, the A/F gauge read between high 12s and low 13s. I think I'm going to jet it down probably 4 sizes before I take it on the road and check it under load. But I think I'm going to change the oil pan and intake gaskets first, while I have it on jack stands instead of going through all the effort of letting it down and lifting it back up again. I may start to tackle that later this afternoon but I need to mow the lawn, it's getting out of control.
 
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Sounds good on the ignition site.
Keep in mind, that when the power valve opens it will become very rich (PVCR holes in the primary metering plate are to big for street use) on the double pumpers. So don't jet down when the power valve is open and your reading is to rich. Your engine will then run to lean in mid-load cases (everywhere where the power valve is closed).
But for the first step I would also think that primary jet size of ~64 will be right (was you stock jet size 67?).
 
And now I have ANOTHER project!! YEAH ME!!! The drive belt on my mower broke about 1/3 of the way through the lawn. :nonono:

The primary jets are 71 as that was the stock size listed for the 4777. When I revved to 3000 I held it there for a minute or so in hopes that the squirter shot would be burned and wouldn't skew the numbers. I'll need to pick up a longer piece of vacuum hose as well, so I can watch it while driving. Mine is only long enough to watch it while I'm standing by the front wheel.
 
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No real updates on the Cobra, but I did rummage through the extra Holley parts I have stashed. I have all of these main bodies and probably enough other parts to put at least 2 more together. I ordered a rebuild kit for a 4160 to put one together, I think I'm going to go with the 1850-3 body. So I'll probably mess with the 650 this weekend as well as the gaskets that need replaced, then rebuild the 600 vacuum secondary and mess with that later.

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This post is more for my reference so I don't have to search for this stuff later. This is the Holley PDF document for their main body part numbers and corresponding parts for a complete, off the shelf carburetor.


As far as this document goes, the 1850-3 and the 1850-2 are both 600s. They both get number 66 primary jets and have side hung bowls and both have 134-9 metering plates.

The 3910 is a 780 double pumper with 71 and 76 jets with center hung bowls.

The 3310-2 is a 750 vacuum secondary with number 72 primary jets and center hung bowls. It has the 134-21 metering plate.

And the 4749-3 isn't listed but appears to be a 600 vacuum secondary destined for MOPAR engines from what I could find through Google. Apparently these are side hung bowls as well, but I have no idea about the rest of it. :shrug:

Edit: Pics are for reference if I decide to swap the metering blocks to get rid of the plates and use actual jets on the secondary side.

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I anticipate progress on this this weekend. The forecast is saying partly cloudy and 87*F tomorrow, a lot different than it has been the past couple of weeks....
 
Finished changing the oil pan gasket (https://www.stangnet.com/mustang-fo...ge-or-starter-replacement-in-a-302-ii.916401/) and the intake manifold gasket and I'm now taking a break. :) I have a couple things left to button up on the intake yet, but the plan is later this afternoon I'll have the car on the road and watching the a/f gauge. While the carb is off now, I'm going to jet both primary and secondary sides down about 4 sizes and see where that gets me.

But, before I started this morning, I ran to Harbor Freight and picked up a new jack. I like it so far! I'd definitely recommend it as long as it holds up....

 
I think I'm going to call it a success. It was 84° F today, a little on the cool side of average for around here which, in my mind, should work well. I ended up taking the jets down to 66 and 68 from 71 and 75 to begin with. I fiddled with the idle mixture screws a little again after the car warmed up and adjusted the idle again. Afterward, I ran to the gas station and filled it up. On the short drive the gauge ranged from around 12.4-14. something. I even stomped on it for a second and it dropped to a low of 10.something before bumping up to the 12s and 13s again. Seems that's about where it should be going from a bunch of different internet sources. That and I think I'd rather have it a tad on the rich side vs on the lean side and risk detonation. So that's where I'm going to leave it for now. It's going to be hard to not watch those numbers! Lol
 
A little. It felt a little more snappy. That and I wasn't dust cropping anymore. Lol

I intended on taking it out and shooting a little video while having the gauges visible in the video but couldn't find my renewed tags. By time I found them it was starting to get dark so I held off on that idea. It was supposed to rain overnight again but I think today is supposed to be a lot like yesterday. If it is I'll try to get out and record a drive.

And the added mufflers help A LOT. It's definitely quieter and I don't think I notice any change in how it sounds other than being quieter. Hopefully the video will reflect that as well if anyone compares it to an earlier in-car video. So far it's been a win on all fronts concerning everything I've done with the car recently. :)
 
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And the added mufflers help A LOT.
Very good that my recommendation did help you.
Sounds like your car is getting there, where you wanted it.
If you still have at highway speed a drone, i would change the rear muffler from the current chambered design to a flow-trough like magnaflow. The chambered mufflers are less effective at lower mass flow than flow-trough. Beside you car will pick up some performance because of the lower back pressure. At WOT the flow-trough are louder than the chambered mufflers, but this is where car guys usually want it loud.
 
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Ok, I lied. I decided to take the jets down a little more. :D

The primaries are now down to 64 (the smallest jets I have) and the secondaries are down to 66. I'll take it for a drive later to see where everything stands and I'll try to set my phone up for a video so everyone can see what it ends up with.
 
I found this article this morning which makes a LOT more sense than some of the other sources I found earlier.

 
Just got back from a short drive. I tried to record it with the gauges in view but it didn't really work. My mount fell after about a minute of driving.

But, all seems to be running well until I floor it and open the secondaries. I was only able to try that a couple times and the first seemed to read lean in the 16s. The second time it didn't drop quite so much and stayed in the 15s for a split second before returning to the 14s. Is appears the secondary jets need to go up, but the primaries seem to be in a happy spot. Cruising it remains in the mid to high 13s. Like I said, those are the smallest jets I have, so that's where it's going to stay.
 
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