tricked map sensor outpt v.

Has anyone ever tried connecting a 4.3 / 4.7 volts Dioed from map sensor output signal wire and dumping any overloaded voltage to map sonsor -/ground wire ? How is this dumping overloaded signal compare to GM 3 bar map sensor?
Will GM 3 bar map sensor hook up to R/T's map sensor connector terminal? Any info on low impedence/high flow injecotrs required to run 15+ psi on 92 Spirit R/T, those stock injectors indicated 225, how are these injectors perform incomparison to othersin turbo Dodge families ???
Are those injectors on Neon SRT-4 flow any better than T3 or T4?Is there a modified ECU for Spirit R/T?

Thank you for any advise offer.

Dow

Yes,we do it all the time,been around for years.We have many vendors that can supply just about anything you want.Go to the vendors section and the links section and read up a lil.

Rob,

Please, excuse newbee for asking stupid questions on an issue which have been asked 1,000 times before! If you have any info. on R/T's injector flow rate and any compatible upgraded ( highflow/low ) impedence injectors, would be greatly appreciated.
I had already visited suggested web site, but I could not find much info on R/T's performance parts. What is your experience in using 4.3 volts diode VS. GM's 3 bar map sensor?

Thank you

Dow

You are talking about two totally different things here.

Adding the diode "masks" higher map voltages from reaching the computer. Basically, you are capping the output at 4.3 volts so that the computer will not go into overboost shutdown. At map signals above 4.3, the computer will NOT add fuel. Basically, you are on your own above 14-15 psi of boost.

Using a 3-bar requires a computer calibration that is programmed specifically to handle the different signal sent from the map sensor. This will allow the computer to introduce more fuel automatically as boost raises above 14-15 psi.

You can install a Zener on your stock computer, but you cannot install a 3-bar map on your stock computer.

The question was: what has been your experienced in GM 3 bar map sensor with your modified computer compared to 4.3 or 4.7 diode with 5th injectorCold start injector)???

The 3 bar map monitors boost pressure above the 14.7 psi of the 2 bar stock setup, compare: using the cold start, diode and manaul boost control to go beyond 14.7 psi of boost is A MUCH CHEAPER!! way of getting that kind of boost, the other way being 3 bar map, +40 injectors and a recalibrated computer is expensive. Performance I would say goes to the better setup because the ecu (spark curve, injector width ect.) is made to do that where as the cheap setup is using the stock curve and fuel setup to go past 14.7 psi, your basically dumping fuel in with the extra injector. I use the cheap method, IT WORKS! my ecu is a TI and only boost to 7psi stock, I add fuel from that point via a Saab cold start.

[glhsken]

Quote:

Originally posted by dow R/T - 9 The question was: what has been your experienced in GM 3 bar map sensor with your modified computer compared to 4.3 or 4.7 diode with 5th injectorCold start injector)???

Your R/t is no different than any other T/d electronically with regards to this area.

#1. A 4.3v diode would be a bad choice. 4.7v corresponds to the higher 14.7psi boost cut-out.

#2 TIII injectors are the exact same as TII. 33 lb/hr units

To answer the experience ???..

Stock everything (stage II computer), the zener did just fine. to 20 psi for me

Upgraded Turbo, I/c, fuel... Blew a piston at 20 psi on a spike. Very fine line between too much fuel to idle and enough to support the boost. Race gas was required to run above 17 psi.

Recalibrated 22psi 3 bar set-up. I run around all day on pump gas.

I saw someone say the cheaper way works fine. It does, until you blow just 1 piston. Add the cost of that repair and you've spent more then the recal method.

Cal 150
injectors 140
3bar map (plugs right in) 60

Not to mention, you don't have to worry about an external system failing and leaving you lean (the cold start)

I totally agree with you on that, in my case I didn't have the money, I would like to go with the better ecu ect, now I just watch my fuel real close and pray the 5th doesn't fail.

the diode just stops the computer from going into over boost shut down. you have to add yoru own fuel. but there are tons of ways to do that..
i chose a ad/fuel/pres/reg/ and a FMU and larger injectors. it would manualy control my fuel flow by adjusting the fuel preasure in corralation to boost.. but at 14.2-7 PSI. the computer is out of fuel .. you have to do it yoru self.


you can do a 3 bar map calibration but it is NOT workable on a stock set up... they are not plug and play they use different voltage/PSI skew than a 2 bar..
so you get a custom calibration.. that is fine if you want a plug and play deal and know you wont go beyond what is programed into the computer... but if you change the sir flow into the motor other than boost ( say you go to a big valve head and poort the intake and change the cam) then the aftermarket calibration cant compensate.. it is programed off a MAP sensor which only reads preasure/vaccum.. it doesnt "know" and cant "read" the actual air flow in the motor. so . you will go lean and have to reporgram..

you can do it your self. and watch the guages and keep and eye oin plugs and tune your fuel your self. and be able to update it your self and control it yoru self.
or you can be at the mercy of a computer all day.. with that much custom work and modifications and a constantly changing and updating of perfromance parts i am chosing the manual route so i wont have to pay for a recalibration evertime i change something . i just monitor the A/F and EGT gueag and read the plugs . then add or subtract fuel to my personal needs.

but.. YMMV

Gentelman,

Thanks for good info. My 92 R/T has not run into lean condition at 14 PSI yet, IAW A/F gauge. However, I really wish to push it beyond 14.7 psi ~ 15 or 16 safely. I love the idea of cold start injectors, and already have 2 ready to be in install. The small banjo fitting with tiny plastic tube attached, could 3/16" fuel line
slipped over this end with out any fuel leak once clampped down?
Radio Shacks has 5.1 diode instock but not 4.7 Volt in their inventories, where can I purchase some? Any info on how to quiet down those noisy lifters or an adjustable cam timing gears compatible for R/Ts. No one has any adjustable cam gears listed for TIII, would thsoe made for neon fit?

Stay COOL , as always.

Dow

heh mail me a buck and i will mail you a 4.3 or 4.7 diode../
justin foden
12742 woodland drive
jacksonville florida 32218..

hmm./ dont know to much about T3 top ends..

1st. Class mail is coming your way.

Please, include a brief instructions & diagram.

Thank you

you want a 4.7 or 4.3? let me know

4.7 V diode will be the best choice, any other toys for our turbocharged Dodge?

Thanks

uhh full manual valve bodies and intercoolers..