Ok, I apologize if this is mentioned somewhere else please, if it is then please send me that direction and close this thread. I am new and tried to search around to find the possible solution, found one thread mention that the IAC was the culprit but that was about it.

Anyways, I've just installed a new Internal Wastegate V-Band TurboCharger. T3/T4, 8PSI, .63 Trim, .60 A/R along with a FMIC, Greddy Type RS BOV, Missing Link, Braided Oil Line Kit, and other misc. gaskets and fittings etc. I have a 1999 GS (in case you were wondering)

I'm using stock internals because I've read on countless threads that running 8PSI wouldn't harm anything. (*crosses fingers*)

Now I haven't taken it out on the road, but my mechanic says that he thinks it is running too lean. He also mentioned that I would have to send out the ECU to have it tuned. I didn't think that I would have to do that considering I was trying to boost just 8PSI. I have not purchased all the parts I had intended to yet ... I wanted to buy a FMU, a Fuel Pressure Regulator Kit, new Fuel Pump and anything else that I might need along the way.

My questions is this: Would those Fuel management parts solve my "lean" problem without tuning the ECU?

Thanks for any help or advice! I've been using these forums for so much help thus far.

Never turbo'd a 420A so I cant tell you about the FMU parts, but I will say that you cannot tune/modify a stock N/A DSM ECU in anyway. They are encased in epoxy. You can get an AFX ECU if you like waiting for months to get a part, or you can go Megasquirt which is well worth the price.

You need to buy an sfmu before you boost it at all. If you don't get one, you will blow your motor shortly.

Originally posted by 740 turbo brick
You can get an AFX ECU if you like waiting for months to get a part, or you can go Megasquirt which is well worth the price.

Sorry, bit of a rookie if you haven't already guessed it. What is the AFX ECU or the Megasquirt?

Thanks!

AFX ecu will not help with a boosted 420a. Megasquirt is a standalone computer. If you want info on them do a simple search.

Originally posted by Wes Tank
AFX ecu will not help with a boosted 420a. Megasquirt is a standalone computer. If you want info on them do a simple search.

Yep, did a search through Google. Thanks.

Welcome to 2gnt!

The factory ECU isn't tunable, so you can just ignore that concern for now. However, without any sort of variable rate-of-gain fuel pressure reglator (FMU, Super FMU) your setup has no way to provide additional fuel to compensate for the boost you're running. Yes, you'll be dangerously lean under boost, and yes you can cause engine damage even at 8psi without additional fuel. I would disconnect your internal wastegate and block it OPEN to prevent spooling the turbo until such time you can purchase and install an FMU at the least. Your stock injectors on a stock fuel pressure regulator, a 12:1 FMU and upgraded fuel pump (typically a walbro 255 HP) should keep you safe. A wideband gauge would also be a sound investment, I have and recommend the Innovate LC-1 with the XD-16 gauge addon.

Originally posted by DarkOne
Welcome to 2gnt!

That right there is a prime reason why I signed up for this forum. It actually has people that will read a question and actually help someone. I appreciate your time and effort and thank you for the response! That helps a ton.

:)

You will also need a fuel cut defender as well.

Thanks for the tip!

So this is what I've bought since I started this thread:

-Vortech FMU
-Vortech Air Bleed Valve (since I didn't spring for the SFMU)
-Walbro 255 HP
-Turbosmart FCD

My next question is, do you think that I'll be fine for at least a little while running stock injectors (maybe get them cleaned etc.)??

Thanks again!

As long as you keep the boost at reasonable levels and monitor your A/F ratio, yes, you will be fine on stock injectors.

Yeah, I don't plan on going past 8PSI because I don't want to change the internals. (already spent enough money on this project as it is)

Hopefully next year I'll have enough saved up and I can rebuild some things and push the PSI up.

Thanks again for the help!