Proper tuning sequence?

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Proper tuning sequence?

26ftcobraBBF
I know you all could help me out with this question..
I'm wanting to dial the Cobra in so I know it's running/ starting the best it possibly can. Please let me know what the proper sequence is for the tasks below.
Ignition timing, curb idle, fuel mixture, choke kick off, and accelerator pump,.....and how the heck do you find the sweet spot on the dash pot?
Let me know if I missed any crucial steps. Thank you
Mike
'85 Ford Cobra Econoline E350 7.5L carbureted thing of beauty
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Re: Proper tuning sequence?

ArdWrknTrk
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Ignition timing... like just static timing?
Or base timing, centrifugal-curve (slots, weights and springs) , vacuum curve and total ?

Fuel mixture... just idle, or power valve, boosters, secondary springs, secondary metering plate, main jets, etc..

A lot of tuning there is no a-b-c-d.
You make a mixture adjustment, you have to go back and reset the curb idle.
You change the advance springs and you have to either add fuel or back it out of the rattles.
Depending on weights and springs, the centrifugal is coming in not far above idle (not often in our trucks, and less likely in an RV)

Accelerator pump cams can be changed or a different hole can be used.
This is more of something to address if your rig bogs instead of pulling.
You KNOW it isn't going to peel out, tires smoking.

Not sure what you mean by choke kick off.
Lots of chokes have a vacuum pull off, which cracks the choke open more when the engine starts.
You also have a fast idle cam that can have multiple steps.
This will hold the throttle slightly open until the engine is warm enough to idle properly (not full operating temperature)

It takes experience to juggle these settings in order to optimize your tune.
No one can say X carburetor needs to be 1 5/8 turns open on the idle jets in any 460.
Engines wear. Some have a different cam. Winter vs Summer fuel. The phase of the moon, today.

Bill Vose can help walk you through it, but no one can tune your truck over the internet.
It's down to you to understand the subtle clues and accurately report subjective observations.


 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.
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Re: Proper tuning sequence?

26ftcobraBBF
Awe man!!! (little kids voice) haha..

So in terms of basic, I have a new holley that the factory has set, and they say,         "it shouldn't" need any monkeying around with, so setting carb adjustments aside for now, and just talking timing is I have stock distributor from O'Riley's with a vacuum advance ( nothing fancy). This here is probably the dumbest question you've ever considered answering, but with the timing I know it says to unplug the vacuum advance and plug the hose, when doing that should the engine be warm (low RPM), or on start-up (with a higher idle)? I've already set timing 8° btdc as the under hood label suggest. The suggestion is based on all emissions equipment in place, should I set the timing differently than stated due to it not being an emissions ran system anymore? Ok and here's the dumb question since it's already set, if I put my timing light on it to verify where is now, would I need to remove and  plug the vacuum advance hose again to get the correct reading? Man I think I'm illuding common sense asking that, but I'm gonna let it fly..
To be honest I think it runs pretty good now, maybe im thinking that because it use to run really bad and that's all Ivev known from it. I'm thinking it may have a growing issue with the control module that I may just replace because there fairly cheap. It seems to run a little better before it warms up all the way, and also runs a little hot intermittently. I don't know though. That's why I mentioned it. The cooling system seems to be in decent shape with a new water pump, radiator cap, and a new thermostst. The radiator seemed ok.

On Sun, Dec 13, 2020, 11:49 PM ArdWrknTrk [via Bullnose Enthusiasts Forum] <[hidden email]> wrote:
Ignition timing... like just static timing?
Or base timing, centrifugal-curve (slots, weights and springs) , vacuum curve and total ?

Fuel mixture... just idle, or power valve, boosters, secondary springs, secondary metering plate, main jets, etc..

A lot of tuning there is no a-b-c-d.
You make a mixture adjustment, you have to go back and reset the curb idle.
You change the advance springs and you have to either add fuel or back it out of the rattles.
Depending on weights and springs, the centrifugal is coming in not far above idle (not often in our trucks, and less likely in an RV)

Accelerator pump cams can be changed or a different hole can be used.
This is more of something to address if your rig bogs instead of pulling.
You KNOW it isn't going to peel out, tires smoking.

Not sure what you mean by choke kick off.
Lots of chokes have a vacuum pull off, which cracks the choke open more when the engine starts.
You also have a fast idle cam that can have multiple steps.
This will hold the throttle slightly open until the engine is warm enough to idle properly (not full operating temperature)

It takes experience to juggle these settings in order to optimize your tune.
No one can say X carburetor needs to be 1 5/8 turns open on the idle jets in any 460.
Engines wear. Some have a different cam. Winter vs Summer fuel. The phase of the moon, today.

Bill Vose can help walk you through it, but no one can tune your truck over the internet.
It's down to you to understand the subtle clues and accurately report subjective observations.


 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with an Edelbrock 1826 and Performer intake.
Too much other stuff to mention.



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Mike
'85 Ford Cobra Econoline E350 7.5L carbureted thing of beauty
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Re: Proper tuning sequence?

ArdWrknTrk
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I see I'm not the only one working overnights!  

If you've read the emissions sticker you know that all adjustments should be made at operating temperature.
i.e.fully warmed up on the gauge is reading... whatever is a normal reading.

Often I will take a small mosquito hemostat and just clamp the rubber line going to the distributor.
This saves messing around pulling the line off and finding a piece of masking tape to cap it so you don't have a vacuum leak.

Yes, any time you check the static timing the vacuum advance must be disabled.

You've got an 80457-S, correct?
That carb should be close.
If anything Holley sends them out safe (a little rich) IME.

When you say "runs hot intermittently" that would have nothing to do with the module.
But it is worth it to purchase a quality replacement.
Many of us know about modules with no cranking retard or no heatsink contact for the transistor.

On the distributor, is it something specific to an E-350 motor home?
Did they ask you for the calibration code before handing it to you?
Or is it a generic DSII distributor?
The slots, springs and vacuum pot could be for anything, if they didn't.
And a 3,500# Mustang is NOT a motorhome.
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.
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Re: Proper tuning sequence?

ArdWrknTrk
Administrator
This post was updated on .
If you are just making basic settings and not taking a dive into recalibrating everything, probably the best thing you could do for power is to install a 'straight up' timing set and bring the base ignition timing to 10 or 12°.

You say the water pump was just replaced....
Too bad, because you were 90% of the way to the best $50 upgrade you can ever do to a 460.

https://www.amazon.com/dp/B001EHBYVC/ref=cm_sw_r_cp_awdb_imm_t1_JO01Fb7M9T2MY
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.
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Re: Proper tuning sequence?

Rembrant
This post was updated on .
In reply to this post by 26ftcobraBBF
I don't know how well this correlates to an '85 carbed 460, but I talked to Scott at Parkland Performance about mine (460 EFI) and the two things he suggested were to set the base timing to 13* btdc, and install a 180F high flow thermostat. Not sure what the timing advance is the EFI trucks...but Scott would have a good recommendation for what it should be.

Edit: Below I'm referring to my carbed 302. Above I was referring to the 460 EFI in my RV (now sold).

I'm no expert, but with a warm engine I set my timing and then played around with my idle mixture screws and idle adjustment, and a couple times had to go back and adjust the timing again. I was using a vacuum gauge, and I also had the benefit of having an AFR gauge installed.

This was also with a new Holley 4160, which had previously been re-jetted from the stock #66 jets to #68. I could probably swap a set of #66 jets back in there now but it's running so well I don't want to screw with it.
1994 F150 4x2 Flareside. 5.0 w/MAF, 4R70W, stock.
1984 F150 4X2 Flareside. Mild 302 w/ 5spd. Sold.
1980 F150 4X4 Flareside. 300i6 w/ 5spd. Sold in 2021.
1980 F100 4X2 Flareside. 351w/2bbl w/NP435. Sold in 1995

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Re: Proper tuning sequence?

ArdWrknTrk
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Scott always offers good advice.
12... 13* whatever it will take with no hint of detonation and no laboured cranking when hot.

Right, back and forth, back and forth.
Having a wideband AFR is a huge help.

EFI engines came with a straight up double roller timing set and (IMHO) that is the one best trick for an otherwise stock carbed engine.
Not to mention you get rid of the plastic gear that always clogs up the oil screen.
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.
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Re: Proper tuning sequence?

Rembrant
In reply to this post by 26ftcobraBBF
For what it's worth, I've purchased three different Holley carb books. One of them was a decades old reprint, and the other two were much more recent. This one below I found fairly helpful.

https://www.summitracing.com/parts/sad-sa216?seid=srese1&gclid=CjwKCAiAt9z-BRBCEiwA_bWv-HUzlGrXrbaOpl3D-bXVxhe3oPoJp3Pl-nmXr1Z_VcDFJ76akENWQxoCRNEQAvD_BwE

They're not detailed textbooks or anything...they're almost more of a coffee table book if that makes any sense, but they're handy for a quick reference of basic how-to's and techniques. If you enjoy reading up on this stuff, it's worth the 15-20 bucks to have it.

I now have a nice little collection of SBF and Holley books. Now that everything is running nicely of course I don't use them, but they're nice to have if I do need them.
1994 F150 4x2 Flareside. 5.0 w/MAF, 4R70W, stock.
1984 F150 4X2 Flareside. Mild 302 w/ 5spd. Sold.
1980 F150 4X4 Flareside. 300i6 w/ 5spd. Sold in 2021.
1980 F100 4X2 Flareside. 351w/2bbl w/NP435. Sold in 1995

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Re: Proper tuning sequence?

Gary Lewis
Administrator
In reply to this post by 26ftcobraBBF
I agree with Jim.  But you may be planning just basic things.  So let me suggest a process.

I'd play with ignition timing first, and by that I mean base timing or what Jim called "static" timing.  It can really change other things, so if the engine is running fairly well play with it first.  Disconnect the vacuum advance and set the timing to what the sticker calls for plus two degrees.  Reconnect the vacuum advance and drive it and see how it responds.  Especially listen for detonation or pinging.  And see how it starts - does it kick back or start normally.

If it liked +2 degrees give it +4.  And maybe +6, but depending on what the recommended timing is I don't think I'd go over 14 degrees BTDC or you may have pinging or detonation next summer.

With that done you may have to adjust your idle speed if your vacuum advance is on at idle.  And then I'd adjust the idle air/fuel mix.  After that the choke since the idle mix does effect the choke.

As for the dash pot, is it the one that slows the closing of the throttle?
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: Proper tuning sequence?

26ftcobraBBF
In reply to this post by ArdWrknTrk
I try not to work to many nights but my schedule is dictated by my autistic 4 year old, and he's burning the midnight oil these days..ugh...

Yes on the Holley carb, that's the one

Makes sense on the hemostat, here on the west coast I think there called a roach clip for some reason. 

Module wise that was something I read on the internet about sluggish performance, and running hot( too lean) but maybe they don't pertain to a carb engine. When you say quality replacement are you referring to just motorcraft,bit is there s cheaper aftermarket brand you trust?

I have no idea about calibration code, and I'm willing to bet the highschool kid who sold it to me didn't know either, but you've got my attention with that where do I find my calibration code, or what it's supposed to be?  Would there be a calibration code stamped on the new one for me to compare to?


On Mon, Dec 14, 2020, 3:00 AM ArdWrknTrk [via Bullnose Enthusiasts Forum] <[hidden email]> wrote:
I see I'm not the only one working overnights!  

If you've read the emissions sticker you know that all adjustments should be made at operating temperature.
i.e.fully warmed up on the gauge is reading... whatever is a normal reading.

Often I will take a small mosquito hemostat and just clamp the rubber line going to the distributor.
This saves messing around pulling the line off and finding a piece of masking tape to cap it so you don't have a vacuum leak.

Yes, any time you check the static timing the vacuum advance must be disabled.

You've got an 80457-S, correct?
That carb should be close.
If anything Holley sends them out safe (a little rich) IME.

When you say "runs hot intermittently" that would have nothing to do with the module.
But it is worth it to purchase a quality replacement.
Many of us know about modules with no cranking retard or no heatsink contact for the transistor.

On the distributor, is it something specific to an E-350 motor home?
Did they ask you for the calibration code before handing it to you?
Or is it a generic DSII distributor?
The slots, springs and vacuum pot could be for anything, if they didn't.
And a 3,500# Mustang is NOT a motorhome.
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with an Edelbrock 1826 and Performer intake.
Too much other stuff to mention.



If you reply to this email, your message will be added to the discussion below:
http://forum.garysgaragemahal.com/Proper-tuning-sequence-tp82242p82246.html
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Mike
'85 Ford Cobra Econoline E350 7.5L carbureted thing of beauty
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Re: Proper tuning sequence?

Gary Lewis
Administrator
I think the calibration code will be on a sticker on the valve cover.  Should look like this:



Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: Proper tuning sequence?

ArdWrknTrk
Administrator
In reply to this post by 26ftcobraBBF
See Gary's reply.
It's also on the radiator support sticker.
That is the only way Ford engineers could put something past the EPA guidelines.
The calibration code details how the carb is tuned, where the timing is set, what kind of Cat may be installed, etc...

Just like the little aluminum tag attached to every carb that comes off the assembly line.
Each application has a specific distributor tune.

Gary and are using the NAPA TP-40 module.
I'm not sure what Cory has.
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.
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Re: Proper tuning sequence?

Gary Lewis
Administrator
Yep.  And I can pull up the calibration parts list if I knew the code, and the parts list gives the part numbers for things like the distributor, carburetor, etc.  Those things were very closely tuned to each application.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: Proper tuning sequence?

ArdWrknTrk
Administrator
In reply to this post by 26ftcobraBBF
I was your kid 53 years ago.  

What's his special interest?
No matter where on the spectrum, we all are fascinated by something esoteric.
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.
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Re: Proper tuning sequence?

26ftcobraBBF
I sure love my boy he's into wheels, and trains. He's high functioning on the spectrum and very smart.
Thank you for asking

On Mon, Dec 14, 2020, 6:41 AM ArdWrknTrk [via Bullnose Enthusiasts Forum] <[hidden email]> wrote:
I was your kid 53 years ago.  

What's his special interest?
No matter where on the spectrum, we all are fascinated by something esoteric.
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with an Edelbrock 1826 and Performer intake.
Too much other stuff to mention.



If you reply to this email, your message will be added to the discussion below:
http://forum.garysgaragemahal.com/Proper-tuning-sequence-tp82242p82274.html
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Mike
'85 Ford Cobra Econoline E350 7.5L carbureted thing of beauty
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Re: Proper tuning sequence?

ArdWrknTrk
Administrator
Back then there was no diagnosis for me, though I would beat my head on the wall I was able to read far beyond my class and had -have- a verbose lexicon.
I grew up in the space age so was into rockets (and chemistry... any kind of material science), but every kid is special and I'm sure he'll put his passions to good use if given the chance.  
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.
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Re: Proper tuning sequence?

26ftcobraBBF
Here's what I have. I don't see a code though....

On Mon, Dec 14, 2020, 7:30 AM ArdWrknTrk [via Bullnose Enthusiasts Forum] <[hidden email]> wrote:
Back then there was no diagnosis for me, though I would beat my head on the wall I was able to read far beyond my class and had -have- a verbose lexicon.
I grew up in the space age so was into rockets (and chemistry... any kind of material science), but every kid is special and I'm sure he'll put his passions to good use if given the chance.  
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with an Edelbrock 1826 and Performer intake.
Too much other stuff to mention.



If you reply to this email, your message will be added to the discussion below:
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NAML

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Mike
'85 Ford Cobra Econoline E350 7.5L carbureted thing of beauty
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Re: Proper tuning sequence?

26ftcobraBBF
In reply to this post by Gary Lewis
Dash pot ..yes with no vacuum, or power, it just softens the throttle closing... Forgot to ask to at what point do I put the vac guage on to check it out? Before adjusting the fuel mixture right?

On Mon, Dec 14, 2020, 4:44 AM Gary Lewis [via Bullnose Enthusiasts Forum] <[hidden email]> wrote:
I agree with Jim.  But you may be planning just basic things.  So let me suggest a process.

I'd play with ignition timing first, and by that I mean base timing or what Jim called "static" timing.  It can really change other things, so if the engine is running fairly well play with it first.  Disconnect the vacuum advance and set the timing to what the sticker calls for plus two degrees.  Reconnect the vacuum advance and drive it and see how it responds.  Especially listen for detonation or pinging.  And see how it starts - does it kick back or start normally.

If it liked +2 degrees give it +4.  And maybe +6, but depending on what the recommended timing is I don't think I'd go over 14 degrees BTDC or you may have pinging or detonation next summer.

With that done you may have to adjust your idle speed if your vacuum advance is on at idle.  And then I'd adjust the idle air/fuel mix.  After that the choke since the idle mix does effect the choke.

As for the dash pot, is it the one that slows the closing of the throttle?
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker in front & 10.25 Spicer/Trutrac in back, & EEC-V MAF/SEFI




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Mike
'85 Ford Cobra Econoline E350 7.5L carbureted thing of beauty
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Re: Proper tuning sequence?

26ftcobraBBF
In reply to this post by ArdWrknTrk
I know bummer on the timing set. Just the water pump was we quite the job. I didn't realize it till it was all back together, then after running it seen a little moisture seep out from where it had previously sealed.
Probably a good thing though is because if I would have done the timing set up I probably would have considered an RV can... You know how it goed to"since your in this far might a as well".

On Mon, Dec 14, 2020, 3:06 AM ArdWrknTrk [via Bullnose Enthusiasts Forum] <[hidden email]> wrote:
If you are just making basic settings and not taking a dive into recalibrating everything, probably the best thing you could do for power is to install a 'straight up' timing set and bring the base timing to 10 or 12°.

You say the water pump was just replaced....
Too bad, because you were 90% of the way to the best $50 upgrade you can ever do to a 460.
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with an Edelbrock 1826 and Performer intake.
Too much other stuff to mention.



If you reply to this email, your message will be added to the discussion below:
http://forum.garysgaragemahal.com/Proper-tuning-sequence-tp82242p82247.html
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NAML
Mike
'85 Ford Cobra Econoline E350 7.5L carbureted thing of beauty
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Re: Proper tuning sequence?

ArdWrknTrk
Administrator
An RV cam involves pulling the intake, rocker arms, pushrods and lifters.
DAMHIK!
Consider a towing cam instead..

But the water pump backing plate is a weak link.
And once you are there......

Actually, the Ford HD cam is quite good for something like an RV if it is set 'straight up'
My old engine would just keep pulling, to 6k.

The convolute weep passages in the back side of the timing case are a darn sight better than coolant in your oil pan!
Be careful not to fill them with sealant on R&R the timing case.

I can offer advice, but it is only my personal experience, and I am no guru.
 Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.
123