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420a turbo swap

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j3st3r

Proven Member
36
0
Jan 23, 2014
somerset, Kentucky
ok i have almost everything to start a swap to turbo i just have a question. how do i off set the fact my ecu can not read positive pressure in the intake? is there a piggy back system or a new ecu? any thoughts? plz post links btw just planning on running a 7-8 pounds
 
ok so just add a wideband?
no need to add to the ecu?
 
ok so i did a search and all im finding is to put a fuel management system on it like a vortech should that be all i need?
 
i was looking at them but OMG the price like i said i was just looking for 7-8 pounds but was i correct in saying thats all i need?
 
ok but still if i add fuel with a stand alone system do i have to anything to the ecu like a piggy back since i cant afford the mega squirt?
 
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Boy here we go. Man adding a turbo to a non turbo. Its gonna get pricey very pricey. In the end you will think, man i should've just got a gst-x for a decent price. That is my prediction. Keep me posted man.
 
I owned a Boosted 420A and it was tuned on Mega Squirt. This will be your best bang for your buck.

Are you upgrading piston, rods?

If you are intentionally looking to be different and you plan on doing the correct way, Kudos to you because its not cheap and it takes some work.

If you are just aching for a little more horse power and want the turbo feel, I suggest you just purchase a gst or gsx.

I bought a 95 gst for $300. It had a rod knock but for under $800 and some labor, I had a running car and it was exactly what i wanted.

If you search around, you can find them. I drove 3 hrs away to pick mine up but it was well worth it.
 
How can you say you have almost everything you need, but have nothing for fuel management? :p

At the LEAST - FMU (Fuel Management Unit, 12:1), Walbro 255lph fuel pump, fuel cut defender/missing link, and a wideband to monitor air/fuel ratio so you don't melt a piston. Don't quote me, but I don't believe you need a fuel cut defender if it's a 95 420a. It's been a few years since I built mine, so the info is a little fuzzy.

http://www.dsmtuners.com/threads/how-to-build-a-420a-stage-2-turbo-kit-for-under-1000.181134/

Memorize that and you'll be off to a good start.
 
thanx everyone i have a complete build forged everything .30 over and port and polished heads this is NO stock block the fmu is on order i was just asking for a small build do i need any thing for the ecu i am about 25 grand in to this build and almost tapped out i just want the turbo.
 

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25k into the build and your trying to cheap out on the most critical part. Yea you can get away with a 12:1 FMU but you will never get the full potential of your build with out a way to tune it.

Megasquirt is by far one of the cheapest methods for tuning the 420a. If you can follow directions and don't mind some research get one of the diy kits from DIYautotune. All you need is basic soldering skills and the ability to read.

MS1 starts at $219 for the kit. MS2 for about $260 and MS3 for about )380.

http://www.diyautotune.com/catalog/megasquirt-iii-c-76.html

I have had MS on my car since around 2011. I love it! I got the MS3 with the MS3x board so I have more than I will ever need. The learning curve is steep but there is a ton of documentation to help.
 
thanx everyone i have a complete build forged everything .30 over and port and polished heads this is NO stock block the fmu is on order i was just asking for a small build do i need any thing for the ecu i am about 25 grand in to this build and almost tapped out i just want the turbo.

Forgive me, I'm not trying to judge; But why in the hell would you dump all of that money to build your engine, if you aren't willing to pony up the roughly $300 it would take to get running on an MSII setup, running just an FMU instead?

You're cheaping out on the one major component you don't want to cheap out on, your tuning solution.

All that aside, if you're hellbent on half-assing it, you can run a Missing Link or an FCD. One (The Missing Link) is mechanical, the other electrical. The Missing Link is simply a check valve installed in-line with your MAP sensor. This will prevent the MAP from seeing positive manifold pressure. The FCD is simply a voltage clamp (IIRC) that wires in to your existing MAP.

Lastly, it says you want to run seven or eight pounds of boost, but your profile doesn't list on what. There's a world of difference between seven PSI on a 14b vs a 20g or an HX40...whatever.
 
Thats alot of CASH!!!! I didn't build the one I bought, but the previous owner only had $4500 into a fully built and blue printed motor along with all the necessities to be able to fully tune the car and make it reliable.

If your paying someone for the work, I would ask where exactly is all that money going.

Don't skimp on your tuning. Make sure you get something that will be able to tune everything needed to ensure this will be reliable and make sure you have a well known tuner do the work.
 
not just the motor the body work, paint, interior, custom fab fenders, audio, video, etc...i built this car to be a very good street car. oh and btw does the fmu go b4 or after the fuel regulator? what should the psi on fuel b?
 
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The 12:1 FMU is going to raise fuel pressure 12 PSI for every 1 psi of boost. So with stock fuel pressure at roughly 45 psi your fuel pressure will be at 141 psi at 8 pounds of boost.

As for placement use google. I don't remember where it goes because I wanted a proper tuning system.
 
ok thank you all for all the insight. and 141 psi is kinda high or is that just me? any sugestions on an fic other than mega squirt ?
 
I have to agree here.... if you already have 25 grand into the car, don't skimp out on the most important part!! Especially if you spent the cash to have the motor built! I would think the money for megasquirt would be cheaper than another forged engine build?

Trust me, the ability to tune your car with a stand alone system will be 100% completely worth the money, and save you time and headaches trying to work around it and "trick" the computer.

141psi is not that high under load. 25-60psi is the normal-ish range for most fuel injected cars at idle. Start going into direct injection, like on the new cars, and that idle psi shoots up to 2500psi!
 
Im trying to think how I could even go about dumping that much into my 420a. I did the math and all together to fully build and turbo with portfueler, Im looking at around 10k invested, including what I paid for the car.
 
ok thank you all for all the insight. and 141 psi is kinda high or is that just me? any sugestions on an fic other than mega squirt ?

Depends on if you have inspections where you live and how strict they are. Both tuning systems are 'off road use only'. I am pretty sure with FIC if you wire it right you can get away with no CEL. But with FIC I believe all you can do is adjust fuel not spark. Don't quote me on that tho. I am an MSer and love it.
 
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