vanillagorilla

iTrader: (1)

From the looks of it, it'll take a lot of work with the factory manifold. I have no clue how the hell to get one to fit in the hole, let alone clamp onto the manifold. All the pics of the 3 bar's I've seen have the electrical connector in the wrong spot and they don't even resemble the factory and some 2 bar MAP's.

I'm thinking of just taping into the vacuum port on the side of the manifold, but with the boost gauge, the waste gate and BOV all referenced out of that port it seems like a bad idea. What about the port on the TB? That might create an obscure reading though. Thoughts?

whitt1

Cobalt SS MAP is 2.5bar and matches our trucks MAP plug.

TurboGibbs

iTrader: (6)

I'm not sure if anyone supports tuning for the 2.5 bar???
I have a 3 bar and now full speed density tuning, well when it runs again
HPT is what I am using. I had software issues to start with but HPT jumped right on it and fixed it. I don't know if I was the first to have it on an 05 truck or the first on a late model truck factory computer system since the software wouldn't work. Anyhow, i'm using the 3 bar map that came with my autometer cobalt boost guage. It is the old style that used a vacuume line going to it.

CHEVY6000VHO

iTrader: (2)

I don't get this mapping stuff.
Elaborate a little please.
What are the benefits of them?

Jim

whitt1

The Cobalt 2.5 bar MAP works fine with my 2bar HPtuners,I did leave the stock sensor in the intake manifold and run a vacuum line to the the 2.5 bar MAP the vacuum port is smaller on the Cobalt 2.5 bar MAP.

TurboBerserker

iTrader: (1)

A 3 bar tune would work as well most likely. You just need to get the scalar correct in any case.

TurboGibbs

iTrader: (6)

1 bar map only reads up to 1 atmosphere 14.7 psia which is 0 psig, it just reads vacume basically.
2 bar map reads from vacuume to 14.7 psig
3 bar map reads from vacuume to 29.4 psig

On a FI engine when you are in boost with a 1 bar map you can tune fueling for rpm only, in a nutshell. A 2 or 3 bar benefits arn't as big of a deal with a supercharger vs turbo since boost is pretty much linear with rpm. But it can still be helpful with tuning since you typically don't need the same amount of fuel @ 2 psi as you do at 10psi. That is how it is really helpful with a turbo because boost is dependent on engine load and it can be anywhere in the rpm band dependent on driving conditions. Basically with 2 & 3 bar maps you can custom tune your fueling with any boost level at any rpm. That is a quick and dirty but maybe it will get you started.

vanillagorilla

iTrader: (1)

Which port did you get the vacuum/boost signal from? Is this with the stock manifold? I think there's enough room on the main port, but if not I'm thinking of using the fuel pressure regulator's port. I like your idea of just leaving the factory MAP in there too. My next question was on how to plug it.

So no 3 bar people? How do you scale a 2.5bar with HPT? I thought you just get 3 choices with custom OS's. 1,2 or 3 bar.

whitt1

I had an extra vacuum port on my Radix intake manifold and the MAP sensor worked with my 2bar tuning,plug & play with HPtuners.

CHEVY6000VHO

iTrader: (2)

So will I be needing a 1 or 2 bar map with these mods: Radix (3.0 pulley), cam 220/570/570/117lsa, meth kit, and Dynatech LT's?
I thought that some of the meth kits came with 2 or 1 bar maps. If so, which ones?

Jim