Turbonator Boost Control T1 or T2?

[ShelGame]

Maybe they're almost the same after all...

So, GLHNSLHT2 posted a vac diagram over in the Turbonator SBEC thread showing a 'T1' vacuum diagram that looks just like a T2 vacuum diagram (here - http://www.turbo-mopar.com/forums/sh...=1#post1021161). Except that it's from a ~'92 car apparently. So, clearly I had to figure this out.

I looked over all of the US cals I have for the '92 T1's (and I'm admittedly missing a few); and they all have nearly the same boost control values as a '90/91 or '89 T1. Not at all like a 'T2'. Thinking about it, I realized that this plumbing will work just fine - as long as the WG Solenoid is plumbed normally closed (IE with no power to the solenoid) so that manifold pressure reaches the WG Actuator. This part is in fact completely backwards from the original T2. But, it's also the best of both worlds. You get the fast spool of the T2 type of boost control, and the fail-safe plumbing of a normally closed solenoid/vac system.

The plumbing in the post above should work with the 'T1' boost control in any of the Turbonator cals. And, I'm actually going to take a much closer look at the '92 boost control code now. It has many added control features that the earlier cals do not. Maybe I can learn some more from it.

I think that the TIII cals may use a similar boost control scheme.

[GLHNSLHT2]

so as soon as the car is on the solenoid shuts for fast spool up and then opens to send boost pressure to the actuator or is the solenoid always open and then just shuts a bit to keep air from flowing to the actuator if the boost level needs to go higher? Just trying to figure out how it has fast spool up like a T2? Or do you need to look at the code some more? Good to know either way.

[cordes]

Very interesting. I remember when that was posted about the 92 stuff. I'll be interested to see where it leads. I've heard some folks say that the boost control at the end of the TIII stuff was pretty darn good.

[bamman]

If you look at the bottom right of the VECI label where it says "When Equipped," you'll notice it looks like there is another label under what is shown. You can see the "ed" from another label under that label slightly askew to the right. You can also see where parts of the old label "bleeds" through like around the bar code and items on the diagram.

It could be someone put the wrong vacuum diagram on the car. There was a time when you could still order these labels from the dealer.

[GLHNSLHT2]

If you look at the bottom right of the VECI label where it says "When Equipped," you'll notice it looks like there is another label under what is shown. You can see the "ed" from another label under that label slightly askew to the right. You can also see where parts of the old label "bleeds" through like around the bar code and items on the diagram.

It could be someone put the wrong vacuum diagram on the car. There was a time when you could still order these labels from the dealer.

Sound in theory but doubtful as I know of the diagram I posted in the other thread and of one on another car here locally that both have the same diagram. Both diagrams show 90+ solenoids as well, Not earlier solenoids a T2 car would show

[bamman]

I just looked at the 92 FSM. It does show the 92 T1 as having the boost control being plumbed from the turbo to the solenoid and back to the wastegate versus the 91 style of from the turbo to the wastegate via the Positive Actuation Harness to the solenoid. Very interesting.

[ShelGame]

so as soon as the car is on the solenoid shuts for fast spool up and then opens to send boost pressure to the actuator or is the solenoid always open and then just shuts a bit to keep air from flowing to the actuator if the boost level needs to go higher? Just trying to figure out how it has fast spool up like a T2? Or do you need to look at the code some more? Good to know either way.

The solenoid is open normally, and closes to prevent the WGA from opening. The boost control software raises the duty cycle based on the boost target. But, it also can go 100% DC for spool up (that's a modification I made).

The T2 boost control is plumbed the opposite - the solenoid is normally closed, and the software goes to 100% DC on startup, and then reduces the DC based on boost target. So, they work exactly the same, it's just that the later version is a fail-safe method.

- - - Updated - - -

If you look at the bottom right of the VECI label where it says "When Equipped," you'll notice it looks like there is another label under what is shown. You can see the "ed" from another label under that label slightly askew to the right. You can also see where parts of the old label "bleeds" through like around the bar code and items on the diagram.

It could be someone put the wrong vacuum diagram on the car. There was a time when you could still order these labels from the dealer.

Could be, but that doesn't look like a 'T2' label. It doe look exactly like the TIII label. And the TIII duty cycle tables look like the T1 also.

Do any of the FSM diagrams show a restrictor? All of the earlier boost control systems used one, but the '92 T1 label posted above did not appear to have a restrictor. I think that would also be a big improvement to boost control response.

[HSKR]

If you look at the bottom right of the VECI label where it says "When Equipped," you'll notice it looks like there is another label under what is shown. You can see the "ed" from another label under that label slightly askew to the right. You can also see where parts of the old label "bleeds" through like around the bar code and items on the diagram.

It could be someone put the wrong vacuum diagram on the car. There was a time when you could still order these labels from the dealer.

That pic is from my car that i took when trying to get help with the vacuum stuff. It is the factory decal and not a sticker on top of another sticker. I will go out to the car to verify though since I see what you are talking about.

But that is how the vacuum lines were routed like. Or at least seemed to be routed like. There were a lot of "repairs" made on broken hard lines and some of the check valves were installed backwards from the diagram when I went through all the lines.

[ShelGame]

Here's another one - Mexican 2.5 T2 from 1991. Uses the same WG plumbing, without a restrictor. And, from what I remember, it has very similar WG Duty Cycle tables.



The other interesting part (to me anyway), is the solenoid controlled BOV. The '92 Mexico cars use this same vac diagram and the BOV code is In the '92 cals; even the US-Spec, though it's not used in the US-spec cars. But, I guess it could be. I can't really think of what the advantage of a computer controlled BOV would be, though.

I need to read the code, I guess, to see when it is activated.

[zin]

On the BOV being computer controlled, I can see some improved drivability if it reacted to "rate of change" in the TPS, kind of anticipating what's needed, and "getting ahead of it".

Mike

- - - Updated - - -

On the BOV being computer controlled, I can see some improved drivability if it reacted to "rate of change" in the TPS, kind of anticipating what's needed, and "getting ahead of it".

Mike

[GLHNSLHT2]

ok, look a bit closer at the T1 solenoid compared to the 2.5 T2 solenoid. See how the T1 has the lines going to the top 2 ports and the 2.5 T2 has them to the bottom 2 ports. That would lead me to believe that they're operated differently. So the 2.5 T2 is plumbed in traditional T2 fashion and the T1 is plumbed in backwards from that. What turbo did the 2.5 T2 use? A garrett like all the US T2 cars?

[HSKR]

Here's a pictureof the full T1 vacuum sticker on my '92. It is definitely a sticker over top of a stick. I tried peeking up a corner to see how easily I could get the tp sticker off to see what was underneath but it wasn't happening. But this sticker is definitely for the 2.5L T1, so I'm thinking the sticker underneath may have been for the 2.2L R/Ts or the 3.0 V6.

[ShelGame]

Yeah, you're right. Maybe I missed that about the '92 Mexico vac Diagram. I'll have to try and find it again. They definitely use the exact same boost control as the US from '92-on. Exact same software, just different cal data.

The '89-'91 2.5 T1 vac diagrams also all show the WGA using the top 2 ports (well, middle port; top port is plugged), with a filter on the bottom.

[ShelGame]

On the BOV being computer controlled, I can see some improved drivability if it reacted to "rate of change" in the TPS, kind of anticipating what's needed, and "getting ahead of it".

Mike

I guess the computer controlled BOV software could check the TPS, and if it's increased, force the BOV closed by switching off the vacuum to it. Might be a little faster to close than simple vacuum control...

Interestingly enough, the stock code doesn't look at the TPS at all. Only current MAP vs. a time-averaged MAP (as well as Baro), and if it's decreasing, it opens the valve. But, it's a Mexico-only application. So, who knows what it's real purpose was.

[GLHNSLHT2]

The '89-'91 2.5 T1 vac diagrams also all show the WGA using the top 2 ports (well, middle port; top port is plugged), with a filter on the bottom.

And that would make sense as if you feed into the middle port and run out the top port that would be normally open, so they cap it off or you'd have max boost. Going out the bottom port would be normally closed, so they just bleed a little out that port by opening the solenoid to raise the boost if need be. So with that thinking the 2.5 T2 would be normally closed like the other T2's. Who knows if I'm right or not but I think maybe this is getting me to a point where I'll be able to hook up and run the boost control on a turbonator cal and be able to adjust it a bit, I thought I had the vac lines ran correctly but I might of been missing a key item which is capping off that one nipple.

[bamman]

Do any of the FSM diagrams show a restrictor? All of the earlier boost control systems used one, but the '92 T1 label posted above did not appear to have a restrictor. I think that would also be a big improvement to boost control response.

Looking at the vacuum diagram, no. There is no restrictor or orifice.

According to Autozone's website (where I get all my vacuum diagrams btw) the 1992 T1 is a one only year when it comes to that diagram:
http://i16.photobucket.com/albums/b4...ps65de3124.gif

[HSKR]

Looking at the vacuum diagram, no. There is no restrictor or orifice.

According to Autozone's website (where I get all my vacuum diagrams btw) the 1992 T1 is a one only year when it comes to that diagram:
http://i16.photobucket.com/albums/b4...ps65de3124.gif

Okaym sinc ethat pic is the same as my underhood sticker but with a "key" to what some of the symbols mean I now have a few questions.

What is the difference between the "T" throttle body vacuum port and the "P" ported vacuum?
The vacuum ejectors on the weird triangle vacuum thing, are they something special and where would one find new ones? Not sure if what is on my car is factory or not.
Why is there more or less an open vacuum line coming of that triangle into the airbox? I would think that would bleed boost off.

Seems there is a lot of redundancy in the vacuum routing as well that could be eliminated/cleaned up Which I've kind of already started by taking the purge solenoid and vapor canister out of the routing on my car..

[GLHS60]

The vacuum ejector is to supply vacuum to the cruise control even when the engine is in boost.
Ported vacuum is only active after the throttle is opened.

Thanks
Randy

[88C/S]

So, which vacuum diagram would you use on an '89 VNT that now has a super60 instead.

[tryingbe]

So, which vacuum diagram would you use on an '89 VNT that now has a super60 instead.

TII.

Although, I never got the boost control to work correctly in Turbonator. I bought and installed an electronic boost controller and changing boost have never been so easy!