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Need some advive for supercharger Installation

  • Thread starter Thread starter ponsai03
  • Start date Start date Jul 4, 2009
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ponsai03

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May 24, 2009
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Jul 4, 2009
#1
  • Jul 4, 2009
  • #1
About a month or so ago I wrote requesting information on H/C/I for my 90' LX. By that time I think I already have done 50% of the work to the point that the lower intake and valve covers were removed from the engine.
Reading here and there changed my plans and now I decided to run a supercharger, Vortech V3 to be exact. No H/C/I will be performed.
Now, I have few questions for my new configuration. Vortech says that no ignition retard box will be needed when running 5-6 psi. But at 5-6 psi, Do I have to start at any determined timing or just leave it as it's from the factory?
Why is timing has to be adjusted when running an engine under boost?
Second: Vortech says that with the supplied FMU and 91 octane, no additional fuel mods needs to me made. Is this true?
What does exactly "tunning" really involves? I've heard this in almost every forum and don't know exactly what it is.
Third: Since the heads are one step away from removal, do you think refreshing the gaskets will be a good idea since the engine is about to get 100K miles? Any recommendation for H/gaskets for boosted engines?
I know I have asked so much questions a nd sorry for that. Any feedbacks would be really appreciated.
1990 Mustang: 73mm Mass air, 70mm Throttle, shorty headers, 2.25" exhaust with Flowmasters, 3.73 gears, 5Spd., Sumitt Racing Ignition box(no boost retard).
Thanks a lot
 

84Ttop

They make new pistons every day, so why worry?
5 Year Member
Jul 2, 2009
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#2
  • Jul 5, 2009
  • #2
First, Your head gaskets are fine so long as the car hasn't been severly overheated. We recently installed a supercharger on a 180,000 mile 94 w/ no problems.
Second, The FMU closes off the return line to the fuel pump under boost, therefore the pressure increases and the fuel feeding the motor increases as well.
Third, with 5/6 lbs of boost, you really don't need an ignition retard
Fourth, tuning is just optimizing your fuel and ignition curves to make more power. If you install the supercharger on you engine everything will be fine because vortech designed it for a stock engine. You are however leaving some hp on the table by not tuning your combo.

Hope this helps
 
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ponsai03

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May 24, 2009
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Jul 5, 2009
#3
  • Jul 5, 2009
  • #3
Thanks. I was thinking on installing a fuel pressure regulator to get more fuel to te injectors. I hasn't run the car with the 70mm throttle and the 73mm mass air but I think that with this combo I will need more fuel anyway along with the SC.
Do you think I'm gonna have any problems using 19lb injectors? Thanks
 

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
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4
0
Miami, Ok
Jul 5, 2009
#4
  • Jul 5, 2009
  • #4
ponsai03 said:
About a month or so ago I wrote requesting information on H/C/I for my 90' LX. By that time I think I already have done 50% of the work to the point that the lower intake and valve covers were removed from the engine.
Reading here and there changed my plans and now I decided to run a supercharger, Vortech V3 to be exact. No H/C/I will be performed.
Now, I have few questions for my new configuration. Vortech says that no ignition retard box will be needed when running 5-6 psi. But at 5-6 psi, Do I have to start at any determined timing or just leave it as it's from the factory?
Why is timing has to be adjusted when running an engine under boost?
Second: Vortech says that with the supplied FMU and 91 octane, no additional fuel mods needs to me made. Is this true?
What does exactly "tunning" really involves? I've heard this in almost every forum and don't know exactly what it is.
Third: Since the heads are one step away from removal, do you think refreshing the gaskets will be a good idea since the engine is about to get 100K miles? Any recommendation for H/gaskets for boosted engines?
I know I have asked so much questions a nd sorry for that. Any feedbacks would be really appreciated.
1990 Mustang: 73mm Mass air, 70mm Throttle, shorty headers, 2.25" exhaust with Flowmasters, 3.73 gears, 5Spd., Sumitt Racing Ignition box(no boost retard).
Thanks a lot
Click to expand...

Yes you can run stock timing with just 5-6 psi, set it at 10* base.

The reason timing is changed is under boost, the air fuel mix in denser and requires less total timing to produce optimum power. Also too keep detonation away.

And tuning is the best way to go IMO. You get the larger injectors and MAF and actually tune the EEC itself setting the target fueling to the correct AFRs and the timing as well. Then you can ditch the FMU.

Depending on what you combo is and MAF, its possible to start pegging the maf with the boosted setup, meaning the ECU cant add any more fuel, and when the stock EEC is tuned to deliver fuel more for a N/A egnine, you can see how things can get hairy real fast. Thats where the FMU comes in, like stated above it raises fuel pressure real high getting the injectors to flow more fuel per given PW.
 

84Ttop

They make new pistons every day, so why worry?
5 Year Member
Jul 2, 2009
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South Jersey
Jul 6, 2009
#5
  • Jul 6, 2009
  • #5
if you buy the complete kit and use the fmu your 19lb injectors will work fine. that is what the kit is designed to be used w/ from votech!
 
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