Build Thread 1978 Fairmont: The point of no return...

MustangIIMatt

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You could always hide an electric vacuum pump from an 80s GM compact or an early Ford Powerstroke somewhere. They're surprisingly quiet and would give you full vacuum at your booster at all times and eliminate the potential trouble spots of a check valve and reservoir.
 
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CarMichael Angelo

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So...the cant leave well enough alone in me is wondering about adding a vacuum reservoir for the sole purpose of keeping a source of permanent vacuum for the transmission vacuum modulator, and of course, the power brake booster.
I am considering putting a one way ck valve on the supply vacuum source and then direct plumbing the booster, and the trans to the reservoir. Right now, when my foot is in it, the car won't shift into 4th because it requires a vacuum signal to do that, and I have a ck valve in that line because the vacuum modulator cannot see boost pressure.
( So obviously, it won't shift into 4th when in boost)
I also have a electric vacuum pump..that i may be able to purpose as a vacuum source..wondering if all im wanting to do is put a vacuum on that reservoir...would this be a good source to do that with?
 

90sickfox

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All the American makes and models are using some form of a vacuum pump ( usually the same exact one ). They are on everything from cruzes to town and countries. If you pljmmed one to a vacuum canister it would hold approx. 18in.hg. and refill when needed. I have one on my booster and it works well. Used it and the pressure sensor from a 2012 turbo chevy Cruz. I grabbed mine from the local pick and pull. Took the pump, relay- on the harness connector, pressure switch, and check valves.

Screenshot_20210201-163427_Chrome.jpg


On other models the relay doesn't just plug on the end of the vacuum pump connector. I still pull vacuum from the engine but the check valves close under boost. The vacuum pump then takes over if vacuum diminishes. The only vacuum reservoir on my car is the 4 inch round ball for the HVAC controls.

I can't find a picture of the factory vacuum switch anywhere on the web. Its just a 12v switch...on at 12in.hg. off at 18 or 19in.hg. it doesn't plug in the booster...but is in the group of hoses for the check valves.

20210201_164610.jpg
 
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MustangIIMatt

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So...the cant leave well enough alone in me is wondering about adding a vacuum reservoir for the sole purpose of keeping a source of permanent vacuum for the transmission vacuum modulator, and of course, the power brake booster.
I am considering putting a one way ck valve on the supply vacuum source and then direct plumbing the booster, and the trans to the reservoir. Right now, when my foot is in it, the car won't shift into 4th because it requires a vacuum signal to do that, and I have a ck valve in that line because the vacuum modulator cannot see boost pressure.
( So obviously, it won't shift into 4th when in boost)
I also have a electric vacuum pump..that i may be able to purpose as a vacuum source..wondering if all im wanting to do is put a vacuum on that reservoir...would this be a good source to do that with?
If the only thing vacuum does for the trans is control shifting into 4th, it could be used for that too. If the transmission is using vacuum for anything else, then it would have to continue using engine vacuum.
 

CarMichael Angelo

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All the American makes and models are using some form of a vacuum pump ( usually the same exact one ). They are on everything from cruzes to town and countries. If you pljmmed one to a vacuum canister it would hold approx. 18in.hg. and refill when needed. I have one on my booster and it works well. Used it and the pressure sensor from a 2012 turbo chevy Cruz. I grabbed mine from the local pick and pull. Took the pump, relay- on the harness connector, pressure switch, and check valves.

Screenshot_20210201-163427_Chrome.jpg


On other models the relay doesn't just plug on the end of the vacuum pump connector. I still pull vacuum from the engine but the check valves close under boost. The vacuum pump then takes over if vacuum diminishes. The only vacuum reservoir on my car is the 4 inch round ball for the HVAC controls.

I can't find a picture of the factory vacuum switch anywhere on the web. Its just a 12v switch...on at 12in.hg. off at 18 or 19in.hg. it doesn't plug in the booster...but is in the group of hoses for the check valves.

20210201_164610.jpg
Yeah, I appreciate that. But i’m thinking i’ll take the easy approach comparatively Having to create a circuit to power the pump, and tie an additional circuit into the mS3 to shut it off when it reaches a certain vacuum is way more than I’m planning on.
i’ll put a vacuum reservoir in the mix, I’ll source manifold vacuum from the intake. I’ll plumb the power booster, and the transmission vacuum modulator into the reservoir and put a one way valve between the intake, and the reservoir
 

CarMichael Angelo

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After my last update, it made sense that maybe the locker was defective..Maybe that thing isn’t supposed to unlock in the middle of a turn going through an intersection. Maybe it isn’t supposed to snap and pop like there is something trying to seize up when going around a corner....Maybe you’re not supposed to be able to spin the one tire in an opposite direction as easily as spinning a tire on an open differential. Especially when the helical diff is 180 degrees the opposite.

So,...at the end of the day,..I call the dealer I got this thing from..He says...Send it back,....Maybe it’s defective..
 
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bird_dog0347

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I think they’re bled. It’s one of those things where I never know if it’s done. I have what feels like a good firm pedal, but I’m always wondering if it could be better. One things for sure, I’ve definitely managed to completely flush out the old fluid out of the system. The front bleeder screws are letting air get past them when trying to do a vacuum assisted brake bleed. I thought putting an oring over the threads of the screw would help seal it, but every time I shut the valve, the oring raised up a thread, and when I opened it again, the oring was above the caliper..
I guess the main thing was that clean brake fluid was pulling out of the caliper..the fact that air was finding its way down the threads may or may not have compromised the process. If i can drag kate down there on Sunday, I’ll do a regular bleed just to check. ( All while listening to how this is making her leg tired).
image.jpg

( this time i wasn’t forced to try and make an old line fit like before,...i started with a new one and bent it to fit)

I ordered a new AC drier..that’ll be here on Sat. If it gets here then, I’ll swap it out and put the thing back on the ground again. Depending on the weather..take it out for a test drive and see if this differential behaves any better with a slightly tweaked axle end.

More frustration to come i’m sure.
Hey Mike, this is what you need for the bleeders to make sure you aren't getting air from the threads.

 

droopie85gt

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Since you're not one to haggle over pennies when working on the Monster, I just noticed something. Maybe you've mentioned it before, but I have BBC waterpump to go change, so no time to search thru this, that, or the other threads. Why don't you replace the radiator? That huge diagonal pipe seems to take away a scenic view of the front of the engine. If not replace, at least take to a radiator shop and have the inlet moved to the passenger side. That is all. Good night.
 
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a91what

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Since you're not one to haggle over pennies when working on the Monster, I just noticed something. Maybe you've mentioned it before, but I have BBC waterpump to go change, so no time to search thru this, that, or the other threads. Why don't you replace the radiator? That huge diagonal pipe seems to take away a scenic view of the front of the engine. If not replace, at least take to a radiator shop and have the inlet moved to the passenger side. That is all. Good night.
what did you just do.... and why would you plant that in his head...

i think you like to :stir:
:think:


hey Mike why do you have that pipe travers across half the united states to get from the water neck to the radiator? :shrug:
 
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CarMichael Angelo

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Since you're not one to haggle over pennies when working on the Monster, I just noticed something. Maybe you've mentioned it before, but I have BBC waterpump to go change, so no time to search thru this, that, or the other threads. Why don't you replace the radiator? That huge diagonal pipe seems to take away a scenic view of the front of the engine. If not replace, at least take to a radiator shop and have the inlet moved to the passenger side. That is all. Good night.
So then,...that’s the critique coming from the peanut butter gallery?.....

I should move the top radiator inlet over? :flag:


Uhhhh...no.

The old ford oriented radiator was 180 degrees opposite of this one..( which now occupies the box that this Chevy oriented radiator came in) Its the lesser of two evils. The ford radiator lower is on the wrong side, so, the “huge diagonal pipe” would have to run across the bottom instead, but the space between the balancer, and the fan leaves no room for that. The upper would have to take a 180, then a 90 to tie it to the factory 2jz upper...

Dont you have some Chevy junk to do anyways instead of picking on my sht?
 
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CarMichael Angelo

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20210204_144956.jpg

This brilliant idea cost me 65.00. Add a couple of hours chasing fittings and hoses to that.
I had the vacuum ga. in a drawer for years now, so that isn't in the mix. Nobody had bulk 3/8" vacuum hose. After going to all three major A/P stores, I finally travelled downtown to the NAPA main store, and they had it. ( But even then they had to look it up in their catalog) :nonono:
When I get back home, I install the thing, and take the car out to see how it will shift. In reality, I don't need the thing, I have 16-18" of vacuum at idle, I just wanted to take the check valve off of the line that goes to the vacuum modulator to allow for full throttle 3/4 shifts. (pretty stupid in reality,...How many times will I actually be flat footing the thing past third gear?) By putting this thing in between I figured it'd hold vacuum and allow for that to happen.

What actually happened was that the 1/2 shift got soft and sluggish versus the neck snapper that it was before. Evidently, putting vacuum on the modulator reduces line pressure to the trans, and the end result was a mushy 1/2 gear change.

Which left me no choice but to put the trans line back onto the manifold, and reinstall the ck valve to keep the modulator from seeing positive pressure.

The follow up road test confirmed, that I got my great 1/2 shift back.

That leaves me with this pointless thing with the power braker booster now the only thing plumbed to it (well and the derelict vacuum gauge..that is still there too) Something that I didnt need for the sake of the brakes at all.....
*sigh*:dead:
The Other thing I learned while doing this test drive today is that 6000 RPM is gonna be it for this thing. In other words,..revving it past that actually causes the boost to drop, just like it did with the Tiny Wheezer. Except Now with there's a completely different turbo in the mix., the only thing I can definitely say is.......................................that the Lag has returned, Other than that...It might be faster, It might be slower.
I decided that I would take my boost gauge and plumb it directly into the compressor housing Like Work Turbo wanted me to do, and then try and watch the gauge while running the engine up to RPM to see what it tells me for boost....The purpose being to determine if there was boost loss through the intercooler..But....That's a recipe for disaster at full throttle. I could only watch it at lower rpms, and what the gauge said, and what Tuner studio said were one in the same. Now, whether or not that changes at RPM's north of 6000,....:shrug:I'm gonna have to either have #1 ride along to watch that, or hook up the go-pro to do it instead.
I also have added new perks too.....For the first time since I've been beating on this engine,..I'm pretty sure I heard pinging.

I datalogged the outing..If anything, There probably is too much timing, a little too lean,...or Too much boost (car made a high of 23.3 psi) for the gas that's in the car.
As to be expected, Once I get the thing back home I immediately pull the plugs...
20210204_162038.jpg

it looks like 1 and 4 have aluminum specs on them.
All 6 look to be way too hot either from fuel, timing, boost, or all of the above.

So then...This thing isn't going any faster than it presently is. If anything it'll be slower cause one things for damn sure....I'm not hurting this engine.
I've already returned the boost duty back to 40% after having bumped it to 44% in November at the track trying to get the tiny wheezer to go faster than it was. Ironically, I'll probably call Boost Labs and talk to the guy about changing the turbine housing to get rid of the lag, and what it makes, and how it runs after that will just have to be.
2021-02-04_14.58.59.mlg
 

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droopie85gt

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what did you just do.... and why would you plant that in his head...

i think you like to :stir:
:think:


hey Mike why do you have that pipe travers across half the united states to get from the water neck to the radiator? :shrug:

Who ME? :oops:

So then,...that’s the critique coming from the peanut butter gallery?.....

I should move the top radiator inlet over? :flag:


Uhhhh...no.

The old ford oriented radiator was 180 degrees opposite of this one..( which now occupies the box that this Chevy oriented radiator came in) Its the lesser of two evils. The ford radiator lower is on the wrong side, so, the “huge diagonal pipe” would have to run across the bottom instead, but the space between the balancer, and the fan leaves no room for that. The upper would have to take a 180, then a 90 to tie it to the factory 2jz upper...

Dont you have some Chevy junk to do anyways instead of picking on my sht?

Well, I gave you the solution in the second part of my post. Take it out, take it to a radiator shop, if there's even one around anymore, have them move the UPPER to the other side, leave the lower in the same place. Problem solved.

Speaking of which...so the Ford rad in the box is passenger upper and driver lower? What's the dimensions? Stock Fox?

Actually my nephew is 21 and takes straight after his dad. All I really did was provide instructions and hand him tools. He's been rebuilding his own dirtbikes since he was 10, worked in a motorcycle shop for years and now works at a high end (like $15k bicycle sales) and is a pretty good mechanic.

He's stubborn like his dad (and maybe me :nono:)he put the fan on before the lower rad hose and fought that spring clamp for 30 minutes. I walked out and said take the fan back off, you can't spend the night here. He said oh no, I can do it. I said well at least take the ONE bolt out of the belt tensioner that your fighting between it and the fan. Boom. Clamp fell in place. I think he would have spent hours trying to get that clamp on without taking the fan back off.

It is still seeping at the front ps intake corner, but it now holds coolant longer than it takes to pour more in.
 

HemiRick

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Theres a reason flow goes in one side of a rad and comes out the other....so the coolant has to go thru the core, if both inlet and outlet are on same side coolant can bypass core.
 
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droopie85gt

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Theres a reason flow goes in one side of a rad and comes out the other....so the coolant has to go thru the core, if both inlet and outlet are on same side coolant can bypass core.

That's why they call them crossflow radiators??? :thinking:That only matters if he drives it long enough to over heat. There's no GoPro videos showing such a thing. I only pointed it out because he seemed to have run out of 3AMD discussion points, but I see the turbo has spoken, again.
 

CarMichael Angelo

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That's why they call them crossflow radiators??? :thinking:That only matters if he drives it long enough to over heat. There's no GoPro videos showing such a thing. I only pointed it out because he seemed to have run out of 3AMD discussion points, but I see the turbo has spoken, again.
It’s now “ devolved” into reality argument sessions..
In one side of my head it’s like:
Is it really that important that I make XYZ power? That I have go XYZ fast in the 1/8th mile?
Why isn’t the ”fun factor” the critical design element, and making it a really fast, fun, reliable, STREET car not the objective instead? ( Which was the original design objective way back when the Monster was just a tiny little lizard)
Then the other side pushes in : How fast does it have to be for me to consider it fun to drive? How long will that last before it isn’t fun anymore? How long will that be before you’re right back to where you are.........right now?

It is become the literal vicious circle.

When I say “I’m getting there”, each day brings me that much closer to it..I’ll call Boost lab, and see what he thinks about my 2 JZ that will happily rev to 7200 rpm, but won’t make any more power past 6,000.
I think 23.3 psi is the limit for 93 octane..I guess I can dump in more water meth sooner, but again,......why?
If I back this thing down to 20 psi, and it runs w/o pinging, then the reliability quotient goes up exponentially. If I put the street tires back on, ( and I am gonna put the street tires back on).. Then by nature if the beast it’ll feel fast too.

So thats 2 outta three.

Ill call Boost lab here in a bit, and see what he tells me....I’ll let you guys know how that went.
 
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General karthief

wonder how much it would cost to ship you a pair
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How many builds have we read about that made big numbers on a dyno or drag strip then they 'turned it down' for reliability on the street, happens all the time.
It's just a few key strokes and/or a spring change away. Right?
 

CarMichael Angelo

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Well......Hell.

The problem has probably been right under my nose ( literally ) this whole time.

I call boost labs, tell them what’s happening...and he tells me that I need to check the wastegate for sealing, and diaphragm leaks.

“Uhhhhh...I don’t have to check it for leaks,...I KNOW it’s leaking....It has always leaked at the inlet..No matter what I do, it always seems to leave evidence of exhaust gasses getting by it, I can smell it, and hear it.”

Well until you get that problem solved, as boost pressure increases, the exhaust leak you can see, hear, and smell at idle is probably bad enough at 6000 rpm to actually limit boost or actually loose it as RPM increases beyond that.
have you ever put a vacuum on your diaphragm to see if it’ll hold vacuum?

“Nope”

You need to do that to be sure it isn’t leaking,...How big are the air lines going to your wastegate ports?

“1/8”..

You’d probably be better increasing them to 1/4”.

You should command that the gate stay at 20psi as soon as the engine comes into boost to allow it to build pressure sooner instead of later,....you’ll gain more low end torque on what is a pretty low torque engine, and a fairly high friction transmission.

Ever since putting this combo together with the new wastegate, I’ve never been able to get it to seal properly. There has always been a leak there. If there was room so I could put a flex coupler in the tube going to the wastegate inlet, I’d do that, but there isn’t. Maybe I can cut the down pipe, and put a 3” flex coupler there instead, and that might give the mating surfaces enough flexibility to make this sht work..
maybe there’s something wrong with the wastegate mounting flange...I’ll check that too..I need to put a vacuum pump on the Wastegate diaphragm....And I’ll put bigger lines to the gate..

Maybe I’ve found the fix.
 
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