Big Blue's Transformation

[Gary Lewis]

Hmmm, maybe!

It would be easy to put a restriction in the vacuum supply by making a fitting that accepts a carb jet and has hose barbs on either end. But not so easy in the vent as I think it is just a hole in the housing. But, maybe I can drill and tap it to take a little hose barb, and then play with carb jets on it as well.

I'll look tomorrow, but that may be a much better way of smoothing things than doing it electrically.

Actually, I think I may be making this a whole lot harder than it needs to be. (What else is new?) In the illustration below there's a wye in the vacuum line between the valves and the servo, which is where the vacuum line to the dump valve attaches.

I'm pretty sure that this is that wye as I know for sure that the open port goes to the dump valve. So, why not put a restriction in the hose where the X is?

The downside to this approach vs the previous one is that the same restriction is used for both accelerate as well as decelerate. But there's no drilling, taping, etc. Just cut the hose and insert a restriction.

But, aren't most of the restrictions Ford used restrictions one way and a check valve the other? Or were there just restrictions? And, won't they be too restrictive? Look at the size of that hose!

Hmmm, I think I have a small valve that could be used as a variable restriction to test this out.

[ArdWrknTrk]

Actually, I think I may be making this a whole lot harder than it needs to be. (What else is new?) In the illustration below there's a wye in the vacuum line between the valves and the servo, which is where the vacuum line to the dump valve attaches.

I'm pretty sure that this is that wye as I know for sure that the open port goes to the dump valve. So, why not put a restriction in the hose where the X is?

The downside to this approach vs the previous one is that the same restriction is used for both accelerate as well as decelerate. But there's no drilling, taping, etc. Just cut the hose and insert a restriction.

But, aren't most of the restrictions Ford used restrictions one way and a check valve the other? Or were there just restrictions? And, won't they be too restrictive? Look at the size of that hose!

Hmmm, I think I have a small valve that could be used as a variable restriction to test this out.

There are the delay valves you find in the air cleaner housings but there are also V-REST you find in the distributor line.

If you're using ported vacuum you're probably not using the restriction anyhow?

My only thought to using a reservoir was that through the restriction it might take some time to adjust.

[grumpin]

There are the delay valves you find in the air cleaner housings but there are also V-REST you find in the distributor line.

If you're using ported vacuum you're probably not using the restriction anyhow?

My only thought to using a reservoir was that through the restriction it might take some time to adjust.

Are you sure this aggressiveness isn’t normal for this system?

I think mine works good, next week I could go for a drive and compare some things if you’d like.

[ArdWrknTrk]

Are you sure this aggressiveness isn’t normal for this system?

I think mine works good, next week I could go for a drive and compare some things if you’d like.

I think gary still hasn't accepted that even if everything is new.... it's still a 34 year old truck.

Not that I ever expect him to.

[salans7]

I think gary still hasn't accepted that even if everything is new.... it's still a 34 year old truck.

Not that I ever expect him to.

I've seen too many comparisons to his 2015 F150, so I highly doubt Gary will ever accept that his 34 year old truck will never come close to performing like his F150. It's just the engineer in him. They don't know when to stop trying to improve.

[Gary Lewis]

Are you sure this aggressiveness isn’t normal for this system?

I think mine works good, next week I could go for a drive and compare some things if you’d like.

Dane - An auto, like your C6, softens things quite a bit, but with a manual you feel it more. So, while it may be normal I don't like it.

Jim - It doesn't take but a few inches of vacuum to make the system work. I saw 3" of vacuum today and it was still pulling strong. But the system ties into the manifold vacuum on the firewall and there is no restriction at all, so whatever the engine has the speed control sees.

What I don't know is how much restriction will tame it. The size of that hose suggests that a V-REST might be too small, but I don't know. However, tomorrow I'll see what I have in the way of those devices, see if I can rig up some adapters, and give it a test to prove the concept.

Jim & Shaun (and whomever else chimes in before I get this posted) - Yes, it is the engineer in me. I'm ALWAYS trying to improve things. And watching the vacuum gauge twist back and forth tells me that a lot of improvement can be had.

And here's what I'm thinking for a restriction, assuming that a V-REST is too restrictive, like I think it will be. This is a piece of aluminum bored through with hose barbs screwed in from either end and a Holley jet below the right one. I believe I have the correct tap for those jets as I'd planned to use one in my leak-down tester - but didn't.

[ArdWrknTrk]

Dane - An auto, like your C6, softens things quite a bit, but with a manual you feel it more. So, while it may be normal I don't like it.

Jim - It doesn't take but a few inches of vacuum to make the system work. I saw 3" of vacuum today and it was still pulling strong. But the system ties into the manifold vacuum on the firewall and there is no restriction at all, so whatever the engine has the speed control sees.

What I don't know is how much restriction will tame it. The size of that hose suggests that a V-REST might be too small, but I don't know. However, tomorrow I'll see what I have in the way of those devices, see if I can rig up some adapters, and give it a test to prove the concept.

Jim & Shaun (and whomever else chimes in before I get this posted) - Yes, it is the engineer in me. I'm ALWAYS trying to improve things. And watching the vacuum gauge twist back and forth tells me that a lot of improvement can be had.

And here's what I'm thinking for a restriction, assuming that a V-REST is too restrictive, like I think it will be. This is a piece of aluminum bored through with hose barbs screwed in from either end and a Holley jet below the right one. I believe I have the correct tap for those jets as I'd planned to use one in my leak-down tester - but didn't.

Seems a clunky thing when you could put a plastic restrictor in there and change up, as much as you want with a set of number drills.

I have a little Huot set that goes to #80.

It was under $20 (decades ago)

[ArdWrknTrk]

Dane - An auto, like your C6, softens things quite a bit, but with a manual you feel it more. So, while it may be normal I don't like it.

Jim - It doesn't take but a few inches of vacuum to make the system work. I saw 3" of vacuum today and it was still pulling strong. But the system ties into the manifold vacuum on the firewall and there is no restriction at all, so whatever the engine has the speed control sees.

What I don't know is how much restriction will tame it. The size of that hose suggests that a V-REST might be too small, but I don't know. However, tomorrow I'll see what I have in the way of those devices, see if I can rig up some adapters, and give it a test to prove the concept.

Jim & Shaun (and whomever else chimes in before I get this posted) - Yes, it is the engineer in me. I'm ALWAYS trying to improve things. And watching the vacuum gauge twist back and forth tells me that a lot of improvement can be had.

And here's what I'm thinking for a restriction, assuming that a V-REST is too restrictive, like I think it will be. This is a piece of aluminum bored through with hose barbs screwed in from either end and a Holley jet below the right one. I believe I have the correct tap for those jets as I'd planned to use one in my leak-down tester - but didn't.

This thing has what???

Three analog inputs and probably operates at a Mhz, if that?

I'm sorry.

Go buy a 2020 truck.

Enjoy and appreciate this one for what it is. A survivor of days long past.

[Gary Lewis]

This thing has what???

Three analog inputs and probably operates at a Mhz, if that?

I'm sorry.

Go buy a 2020 truck.

Enjoy and appreciate this one for what it is. A survivor of days long past.

This one is hardly a "survivor". Save for the body it comes closer to being a '95 than an '85.

And yes, that piece of aluminum would be clunky, but a V-REST is similar. And once you drill it out you can't go back.

I'm not saying I'll make that, but it is what came to mind to allow tuning the speed control. Perhaps I'll get lucky and nail it on an early try, but I'm doubting it.

As for buying a 2020, I have a 2015 and there's not enough difference to make it worthwhile to change. But, Big Blue is "close" and dialing in the speed control will bring it that much closer. Besides, the vacuum restriction was your idea!

[grumpin]

Dane - An auto, like your C6, softens things quite a bit, but with a manual you feel it more. So, while it may be normal I don't like it.

I hadn’t thought of that.