Austarion

Hey guys ive heard many times that MPI is better than the stock single point injection starions have. But what exactly are the benefits.

-Smoother acceleration?
-more hp?
-more torque?
etc

Thanks

It wont really add power to your engine but it will give it better throttle response as the fuel is directly sprayed into the intake ports instead of being mixed in the throttle body and dividing unevenly between the runners. Since you have better control over the fuel distribution it allows you to raise the boost within reason of your engines limits.

A new ECU will also allow you to get rid of factory restrictions (e.g. air flow meter) and will get rid of all the tired electrical components. MPI is pretty much a gateway to increasing the power of your engine.

Since ive had both, i know the benifets.
Converting to MPI removes all the problems associated with the factory computer and injection setups.

no more running rich
no more weird idle issues
no more dodgy airflow meter

My JA runs a Sonata manifold, no intercooler and a LINK computer.
The engine bay is much cleaner, The car runs very smooth.
Also MPI allows for higher power outputs without potentially damaging the motor. In the factory setup at high power outputs some cylinders run richer while the others run lean(read not good).

Also gets rid of leaky injectors which seems to be coming more and more common in these types of Mitsubishi injection systems.

Just remember to keep costs in mind oped as you have to purchase not only the MPI gear, but the ecu, installation and tuning on top.

Or be like me and buy someone elses hard work , lol rofl rofl

Funnily I just had it recommended to me by a mechanic - said it would be about $4000...... is that realistic? :(

The highest cost will be the purchase of ECU, and getting it installed & tuned.

If you do the bulk of the work yourself (wiring, fitting manifold, ECU, reworked coolant piping, etc) you can save substantially.

Do either of the L300 or the Sonata MPI system bolt straight on without modification?

And I heard the sonata one is more difficult to install but much better for the inter cooler piping...
Is it much harder installing a sonata MPI? and is it better than the L300?

All depends on what you want out of your car.

popular methods are.
*Standard L300 MPI manifold
This is good if you already have an intercooler setup as the throttle body is close to where the factory setup sits. Since it came from a RWD car the thermostat is located in a convenient location.

*Sonata MPI with relocated Throttle body
Usually the throttle body is moved from one side of the plenum to the other. Problem with this manifold is that when fitted to a Starion the thermostat housing sits at the rear of the motor. So some mucking around is required to make it all work. With a throttle body facing the front a more conventional intercooler setup can be done.

*Sonata or L300 intake with custom Plenum
Usually L300 is the better choice as its an easier fit due to thermostat location. Quite a few high power cars run this setup, KIT, Davidbek95, Bodeo. Bigger plenum helps in higher power motors and also lets you place the throttle body wherever you want.


If your on a budget go the L300. Can even run it un-intercooled till you can afford to cool it. When using any of these manifolds you will have to change the injectors and run aftermarket computer.



another thing, why am i awake at 2:30 when i start work at 6

better then having gone to bed early... ment to have started at 5am and gone out to your headlights half popped up and battery dead flat.... for a 2nd morning in a row... grrr

apparently yesterday morning they were going nuts when landlord was working outside, tried waking me up but was in alcohol induced coma lol

looking into a reliable daily today :) KS verada :P

If you can find the L300 manifold, then go for it! Undoubtably the best choice! However I must warn you, these are NOT an easy find! Nor are they cheap, even if you can find one. What's even worse is you need the dizzy to go with it, these are even more rare! I have searched Melbourne high and low for these parts. I got my setup resonable cheap, but the others I've sourced for some other members were not so lucky! Infact, the last dizzy I found, the guy wouldn't let it go for anything less then $350... :x

I got my entire setup for $190! I managed to get the manifold for $100 and the dizzy for $90!

Realistically, be looking in the $200 range for the manifold (make sure it comes with the fuel rail) and probably the same for the dizzy!

For L300 all i could get was one for $300 i think it was. Worth it in the end though.

So the sonata isn't worth the effort?

Also how hard is it to build a custom plenum? And is it worth it?

To make the most of a bigger plenum you will need larger turbo, headwork, cam, built motor, cooler. probably anything over about 250hp will benefit most from a larger plenum.

Some places you can get pre-made plenums you modify to fit the runners on your manifold.

Yes, I think that both the sonata and the L300 inlets have their restrictions and will need to be replaced with larger plenums in order to make the higher power figures.