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a lot of us run a GV with our 2 bar cals, either the stock cals or the ones from MP. work great. but, the 2 bar cals can only allow a limited time above 14.7 psi, then, LM goes into "overboost cutout".

the gv does not effect the boost signal the MAP sensor sees; the gv only effects the amount of boost signal the wastegate can sees.

ok here's the question/idea:

if you have a 3 bar cal, that can control fuel/timing/etc up to about 29 psi, couldnt one still use a gv to control boost onset rate? the 3 bar cal would still be seeing the actual manifold pressure (boost) and so would still be controlling fuel/spark/etc, but by also using the gv, one can dial in a prefered rate of boost onset, just like we are doing with any 2 bar cal.....only difference being that if the gv is set for a psi at or below the cal's upper control limit then we can get unlimited time-at-boost (ie: no overboost cutout).

is anyone using a gv and a 3 bar cal?
or, what's wrong with my thinking here.............
 

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3 bar cal's work the same as 2 bar cal's, only difference is how high it can read. Your thinking is correct. I run a G valve on my 3 bar cal, it's the only way to go for fastest spool-up possible.
 

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I run a grainger on my 3bar cal. Just keep in mind that the higher you go the more "off the factory scale" you are getting. Depending who does your cal, they need to be aware of how high you intend to go.
 

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Una said:
Not to bash TU, I understand Paul has to be able to do it to ALL the different computers, and the cal Rob posted is a SMEC only one. It might not even be possible for a LM or SBEC computer to do it, and that's why Paul doesn't offer it.
Paul's on the D-Cal list. I'm sure he's seen it. He probably just has a different way of doing it. More than one way to skin a cat as they say.

As for the T1/T4 SBEC, the boost control code is nearly the same as the '89 T1. I already modified the boost control routine to allow for switchable boost the same way it works in the '89. I'll post it once I get all the MAP related tables/constants/etc ID'd for a 3-bar setup.

I think it would be a bit harder to add this mod to the LM setup. It's not something I plan to do myself.

-Rob
 

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Una said:
Crazier than that, the cal Rob posted lets me use the factory cruise switch for high/low boost. Cruise switch in the on position would obviously be low boost, turn it off and you get high boost.. heheh, awesome idea there.. :)
Actually, if you think about it, it probably wouldn't be a good idea to run high boost while the cruise is on anyway. I know Jon Berube (not sure if he's on TD.com or not) ran it that way. He said his van kind of took off when the cruise control called for more throttle (and it got a ton of boost). Could make for a wild ride...
 

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I had Paul st mine up for no cut out, I want to be able to control things myself and raise the boost as I see fit maybe I will rig up my own 2 stage controller here soon

I dont see myself getting to 29 PSI anytime soon... till I get a aftermarket rail anyways...

Jeff
 

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You can't run a grainger with a 2 stage cal unless you also set up a selenoid and have a dual stage boost controller also which is just dumb and pointless to have a 2 stage cal then. I had paul do a re-cal and take out my dual stage and back to a single stage because I use a grainger.
 

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moparzrule said:
You can't run a grainger with a 2 stage cal unless you also set up a selenoid and have a dual stage boost controller also which is just dumb and pointless to have a 2 stage cal then. I had paul do a re-cal and take out my dual stage and back to a single stage because I use a grainger.
Why not unless I am misunderstanding?? I have mine set up for 16 psi pump and 17 and up 100 octane! I just use the MBC to put the boost where I want it, I don't need to run high boost on the street and I need 100 in the tank anyhow!
 

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Una said:
I assume your talking about the cal I downloaded, Rob's cal. Not the TU cal. As I couldn't fix anything in the TU cal if I wanted to. Anyways, no, the car doesn't seem to idle and richer than it is supposed to when it's cold. It doesn't stay cold for long.
I meant Rob's cal (I'm Rob - BTW :) ). Some of the other guys running that cal were having rich issues at cold idle (Dean Stillie/Jon Berube). I was just curious if you also had a rich cold idle, and how you fixed it.
 

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Rob,

When I went to 52pph injectors, I had a host of idle mixture issues. It took some tuning of the cold start and base fuel tables to get it right. I know your cal was originally 3-bar/33pph. I imagine that setup shouldn't require any cold start table tuning, but perhaps the lower resoltion of the in-vacuum area on the 3-bar MAP may be causing some errors to build up in the cal?
 

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minimopar said:
Rob,

When I went to 52pph injectors, I had a host of idle mixture issues. It took some tuning of the cold start and base fuel tables to get it right. I know your cal was originally 3-bar/33pph. I imagine that setup shouldn't require any cold start table tuning, but perhaps the lower resoltion of the in-vacuum area on the 3-bar MAP may be causing some errors to build up in the cal?
Yeah that could be. I was also thinking about the Pumping Eff Table. Mopar set it to a constant 86% below 2800rpm. Which, obviously, isn't realistic. I'm wondering if they fudged it a little to make sure that idle was slightly rich. But when converted to the 3-bar set-up, it's too rich. I think I'm going to try setting the PumpEff table to 75% below 2800 rpm and see if that clears up the idle richness.
 

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Una said:
It always weirded me out to see the boost gauge say 10psi, and the O2 gauge still bouncing up and down, because I was only at like 1/4 throttle. That problem is very much gone. :)
agreed, this makes me nervous as well! Good idea!
-mark
 

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minimopar said:
Rob,

When I went to 52pph injectors, I had a host of idle mixture issues. It took some tuning of the cold start and base fuel tables to get it right. I know your cal was originally 3-bar/33pph. I imagine that setup shouldn't require any cold start table tuning, but perhaps the lower resoltion of the in-vacuum area on the 3-bar MAP may be causing some errors to build up in the cal?
I had to pull quite a bit of fuel out of FuelColdEnrichmentCurveA to get it to cold start correctly when I made my 89 T2 a 52pph cal. Have a look at the cold start tables in S60.
 
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