Running really really rich after blower install

[VibrantRedGT]

We got the car running on the 4th of July. We stripped the car down to the stock block a month ago and installed GT40X Heads, TFS Stage 1 Cam, Scorpion 1.6 Rockers, New Pushrods, New Lifters, Edelbrock RPM Intake, 70MM TB. Initially a blower was going to be down the road. However a new Vortech V3i was ordered so we installed that as well. Only having 30lb injectors we decided to run the kits FMU until we can upgrade to larger injectors. We are using the stock MAF until we can get the adaptor to run the Lightning 90MM MAF (adaptor seems to be out of stock everywhere).

Like mentioned, the car started right up on the first crank. The idle was really poor and after hooking it up to the twEECer we noticed the TPS was maxxed, it wouldn't adjust. Pulled it off and noticed one of the ears was gone. Installed a new TPS last night and all is well, idle is fine.

The issue is the extreme rich condition. It's painfully rich. I had Autolite 3924's in the car because it wasn't going to have a blower but I regapped them for a blower. Last night I removed them to install 3923's. Cylinder 2, 4 and 6 were soaking wet, the rest looked to be normal. Put the 3923's and she fired right up and idled perfectly. Rich condition still very bad. Check all my hoses going to the fuel pressure regulator (replaced it while I was playing around), traced all my vacuum, plug wires, etc. No issues found.

Timing, not sure right now because I cannot see it on the balancer. We are using the twEECer to adjust. Fuel pressure, not sure right now because the power pipe is in the way of getting a gauge on the schrader valve. However I'll know these two numbers hopefully tonight.

I know, I know, get rid of the FMU. In due time it will go but for now the 30lb injectors by itself not a good idea.

Pig rich conditions at idle? Under no load, minimal vacuum pressure. I need places to look, don't want to throw parts at it until I chase the obvious. Let me know what you think.

 

[2000xp8]

Sounds like you are complicating things.
Undo whatever you did with the tweecer and just run a meter calibrated for 30's.

Nothing wrong with the fmu setup. It's simple and effective.
It's internet myth that a computer tune is any better than using the fmu.

 

[VibrantRedGT]

We aren't using the twEECer for much of anything. We turned of the smog, egr and calibrated MAF for injectors, other than that the computer is doing the work. We haven't done anything for fuel and timing because the car wasn't running. Now it's running but while the laptop was on the TPS wouldn't allow it to idle. TPS fixed now so it will idle, we can get the laptop back on the car.

 

[09secondGT]

sounds like a mass air problem, does the tweecer show maf voltage?

 

[VibrantRedGT]

I'm thinking MAF too. Was just told we added MAF voltage 0-4.999 on the twEECer. Obviously I'm not doing the tweaking, Rog may chime in. We have a Lightning MAF and if AFM would answer the phone I'm trying to buy the MAF adaptor so we can run it on the car. Right now this stock MAF needs to go.

*Note-don't say the MAF is backwards in this picture, it has been corrected, just laying in fender for pictures.

 

[87AODGT]

why play with the mass air curve at all in the tweecer if you have the stock maf? just set the injector slopes and breakpoints for the 30lb injectors and it should be fine. also make sure the FMU isn't hooked up backwards

 

[Beasty306GT]

ur also missing a vac cap on the throttle body in the pic

 

[VibrantRedGT]

Those were just pictures. The belts weren't on, etc.

The MAF is currently set up as such. When you say FMU on backwards, how is the possible?

 

[VibrantRedGT]

If you look in the picture I posted above you will notice the FMU is installed from the top fuel lines. The book says install from the bottom rubber lines (bottom passenger side). Will having these line up top by the intake fuel rails cause a rich condition. We will reroute the lines correctly this weekend. It's kinda the same thing just maybe a foot away. Don't know it that would cause it.

 

[VibrantRedGT]

I ordered the MAF adapter from AFM today and hope to have it in a few days so we can install the 90mm Lightning MAF. This stock one may be the issue.

Any ides if the fuel lines are installed up high in the fuel rails rather than down low would cause a rich issue? We are going to install those correctly this weekend.

 

[Rick 91GT]

You might be able to run the 30s with out the FMU on that setup.

I dont see where hooking the fmu lines up high should matter, but ive never done that. What disc is in the fmu? What the o2s look like on the tweecer?
I fought a tweecer years ago on the dyno, pulled it off for a pms and never looked back, im not a big fan but guys have had success.

Post up fuel pressure and timing. The 3923 is still fairly hot, try a ngk 7173 much better plug.

 

[FoMoCo17]

I agree you should be able to run without that FMU and determine if its too rich. Sounds like too much to me personally especially if your under 10 psi. Do a calculation on injector sizing to find out for sure.

 

[VibrantRedGT]

Here os the fuel pressure with the vacuum on.

I just took the upper intake off and valve covers. Going to adjust the rockers again and fix the fuel lines.

May remove the FMU and run it without for a little bit.

 

[VibrantRedGT]

Oops, here it is.

 

[FoMoCo17]

Your pressure is better than mine. But, it is not a pressure problem form what i read. Its the sizing of the injectors and then the added amount of fuel due to the FMU which is only activated at low vaccuum in the transition to boost. The 30#'s might be enough w/o the FMU ... if it detonates under boost, get out of it immediatley and re-install the FMU would be the only way to check manually. Have you had any contact with Vortech ... what size injectors do they recommend with your setup? Or, do the calculation. Three good options to follow.

 

[VibrantRedGT]

Vortech says use the FMU with the 6:1 disc. The 30lb injectors with forced induction is only good for 315hp, in NA form it's more like 400, both with 85% duty cycle. However we are going to disconnect the FMU since I have everything apart anyway. It will be a trouble shooting move.

Ordered some parts yesterday, hope to have them in a few days. Really need the MAF adaptor. That one is coming from Pro-m.