1986 460 Smog Pump Delete

[Bullnose Gator]

All emissions were stock, as far as I can tell, other than only having one charcoal canister. I've pulled the pumps and removed all non-essential vacuum lines/hoses.  Thanks to the brain trust here, and all of the posts/documentation I've spent hours scouring through, it actually still runs!

However, the idle is now low and rough (as expected), but before I start adjusting the carb, I was hoping to get yall's opinion on how I've run/capped the remaining vacuum lines thus far.  I capped the exhaust manifold/header tubes for now (spiders and rear), because I'll be installing new headers next.  I found these through another post, but welcome any suggestons for headers that will fit without any mount mods:

https://www.jegs.com/i/Hedman/500/89340/10002/-1

I left the charcoal canister in for now, because I think I'm going to loop the line that runs to the fuel tanks to it, but also need to confirm that I'm right about that line.

Sorry about the lighting in the pics, it got real late, and real dark on me real fast. Thanks in advance for any feedback or advice yall can give me.

[ArdWrknTrk]

Okay, there's no point in capping the EGR itself, or the check valve at the thermactor crossover to the back of the heads (it's a check valve!)
Nor the yellow and blue vacuum trees on the water neck.
If you don't have vacuum going to them, there's nothing to leak.

The rusty little line on the passenger side of the engine bay tees (Y's) to the rollover vent on both tanks.
Yes, that's what connects to the charcoal canister.

[ArdWrknTrk]

Remind me what carb you have?
Because tuning a 4180 is WAY different than a regular 1460.

What cam you have that wants or could use headers?
Generally they fit terribly in 4x4 trucks and most mudders just chop out the liners and run fender exit.

Gary has a nice pair of L&L's that he had coated by Jet-Hot but because he isn't running raised conversion mounts he's had to clearance the frame rail on the passenger side and use an Allen head bolt in the bellhousing because there's no room at all for a socket.

I would also suggest getting the actual Ford heat shield for the clutch slave and a PMGR starter with a heat blanket.
460's, even without the thermactor ports in the manifolds, run ferociously hot exhaust.
(ask Bill, Gary, Vivek, anyone..)

[Bullnose Gator]

Yeah I figured I over-capped. Speaking of, on the EGR, seems like "keep the EGR" is recommended a fair amount. But does that mean just "keep" it attached, like I did, or keep it and the vacuum line too?

Carb is a 4180. I just replaced my original 4180 with it at the end of May. It is a rebuild from Guaranteed Carbs. It ran WAY better than mine before this, so it was definitely tuned as originally intended with the emissions set up.

[viven44]

Your idle is low and rough. That tells me you addressed a vacuum leak which is good  now you just need to recalibrate the idle and adjust the throttle screw to come up to 750rpm or so… if you are running a stock cam the vacuum gauge should read 18” or more

Agreed with Jim that those vacuum control valves don’t need caps by principle but leave them on… may keep junk from getting in those tiny vacuum ports. That should preserve them if you plan to use them

If it’s the stock intake you don’t have a choice, EGR plate must stay as the carb won’t hook up straight to intake correctly but you can cap the vacuum lines (again to keep junk out)

[ArdWrknTrk]

A functional EGR allows a much more aggressive spark advance in cruise,
This results in improved mileage and more apparent power (even with a retarded cam)

By making some of the intake charge inert gases you effectively richen the mixture (of a non-adjustable carb) and stave off knock/pre-ignition from having a too lean mixture

[ArdWrknTrk]

If you want to get rid of the EGR style spacer you can just tap and plug the exhaust port in the intake manifold and use a generic 1"spacer, like I got from Trans-Dapt.

[Gary Lewis]

ArdWrknTrk wrote

A functional EGR allows a much more aggressive spark advance in cruise,
This results in improved mileage and more apparent power (even with a retarded cam)

By making some of the intake charge inert gases you effectively richen the mixture (of a non-adjustable carb) and stave off knock/pre-ignition from having a too lean mixture

Right.  So removing the EGR w/o addressing the spark advance can cause knock/pre-ignition at part throttle.  I had that on Big Blue when I got him as the previous owner had removed the EGR system but hadn't backed off on the vacuum advance and it would ping under load at part throttle, like pulling a trailer or carrying a load.

I got around it by running 91 octane gas when needed, but the better thing to do would have been to back off the vacuum advance.  Assuming your vacuum advance is adjustable you can see how to do that on our page at Documentation/Electrical/Ignition and then the Instructions tab followed by the Crane Cams tab.

[viven44]

I haven't found the correct VCV yet. The one I used for EGR is the 3 port valve and kicked EGR on at 125-140F or so which is probably too low so ran a bit rough.. EGR is off.  No pinging on my mall crawler so far  

I thought I heard some pinging early on as I pressed the throttle while cruising but it was just the engine revving up.

Now my 302 on the Bronco definitely was pinging.... this was early on when I was getting used to carburetors, etc. I had no idea what that strange sound was as I stepped on the gas going 35 when everything else was quiet. I can't even recall that sound now but it didn't belong there. Even the 84 Bronco with myself and a kid was definitely "a load" for the 302

[85lebaront2]

Darth melted the rubber mud flap on the right side with the tailpipe. That is around 15 feet from the engine and has passed through probably 10 feet of dual pipes, the muffler and about 5 feet of tailpipe. This is a non-catalyst truck, but I did still have both smoke grinders installed.

After converting to EFI, I no longer have a smoke grinder as it's only function on EFI is to pump air into the catalytic converter and pre 1988 trucks do not have a catalytic converter on a 460. The heat from the right side manifold melted two vacuum lines that pass between th engine and two reservoirs on the right inner fender. These are probably 18" above the manifold on that side. Left side motor mount has a heat shield on top of it so the manifold heat won't melt it. I wire brushed the one for the new engine and painted it with high temperature aluminum paint.

[ArdWrknTrk]

Exactly why I say use the slave cylinder heat shield and a reflective blanket on a smaller PMGR if you really want to run headers.
Otherwise you're just setting yourself up for failure.

Note that both of these are reflective (IR) and have as little thermal mass as possible.

[Bullnose Gator]

Is the heat an issue only with headers, or am I going to now have lava running through the current exhaust manifolds?

Also, any expectations for how much adjusting ill need to so to the 4180 carb to get the idle right? I just want to have an idea so I don't go to far with it when there could be something unrelated wrong.

[ArdWrknTrk]

Heat is always an issue with 460's.
Moreso with thinwall headers than cast manifolds.

The 4180 is a federally compliant tamperproof carb.
About the only adjustment you have (without modifications) is to pull or chisel out the hardened plugs covering the idle mixture screws.

Then, like Gary said you're either going to have to run premium, retard the ignition advance, or both.

Honestly, you'd be better served by a 600 cfm 1460, 80457-S or a 650 AVS like I gave to Vivek.
At least these options are easy to tune and well supported in the aftermarket.  💡

Headers aren't going to change much of anything unless you get a hotter cam installed correctly and an intake that can flow on top.

[Bullnose Gator]

Correct me if I'm wrong, but I believe they already drilled out those hard plugs when they rebuilt this carb...

[ArdWrknTrk]

It looks like they ground through the base flange to get the plugs out  🤔

While this is fine, it is a violation of federal law to tamper with emissions.
And while I'm sure it's fine in the bayou, that wouldn't fly in Kaliphornia.

[viven44]

Why would the idle mixture be blocked off for emissions reasons? Wouldn't it be beneficial to periodically re-calibrate to a good idle mixture ?

The truck I saw today with a 4180 wouldn't idle under any kind of load.. I am wondering if its a bad idle mixture

[Bullnose Gator]

I think I'm starting to confuse a few things you guys have said so far...and to be clear, I plan to leave the EGR as is.

Since the idle mixture screws appear to be accessible now (thanks to the felons that rebuilt it ), should I start by adjusting those, or start with the distributor advance adjustment instructions that Gary kindly linked above?

P.S. I've been running ethanol free gas, so switching to premium would actually be cheaper here.  I just thought that ethanol gunked up carbs, but let me know if that's a legit concern or not.

[ArdWrknTrk]

$45,000 if a company, and $45,000 A DAY for records keeping/falsified testing etc..
The violation for individuals is closer to $4,300 'per event' whatever that means..

If you have an adjustable advance, like Crane explains in their instructions, then start by following the directions on the emissions/vacuum diagram located on the radiator support.

I usually adjust the mixture for highest vacuum, open up another 1/8-1/4 turn and set the curb idle speed per the sticker, then get into adjusting the distributor.
Sometimes the slot is just too wide and you have to take it apart and either weld up the slot or bush the stop pin.

Scotty has good recurve instructions!   👍

https://www.reincarnation-automotive.com/Duraspark_distributor_recurve_instructions_index.html
https://www.reincarnation-automotive.com/Duraspark_distributor_recurve_instructions_page-2.html

[Bullnose Gator]

Well first, I assumed all 4 plugs were drilled out, but just checked the two in the back and they are NOT.  So replacing the carb with one you recommended is sounding better and better.  

Second, I'm not sure I trust myself to do that recurve properly, and for the price he is selling them already done, it is probably worth every penny in time, frustration, and confidence that it was done right.  

Third, I've seen mention elsewhere of replacing the distributor with a "straight up" one, but haven't looked into what that means.  Is that similar to recurving the stock dist, or completely different?

[ArdWrknTrk]

You want to replace the timing chain set with one that's "straight up" (crank keyway pointing directly at the camshaft)

This is how these engines were first built, before 1970's emissions regulations had ford holding the exhaust valve closed to allow more time for the charge to burn.

I recommend a stock double roller timing set for an EFI 460 (1988 & later)
These are longer lasting than a Hy-Vo type chain and factory approved!

As for buying a distributor, you're going to have to give Scott all the information about your truck, how you intend to drive it & its engine.
Weight, gearing, tire size, carburetor, intake, headers, compression ratio, cam, cam timing, etc...

It might be wise to get all that in place before ordering.  💡