Mike's 50

[reaper71]

Looking really good Mike

Mark

[MIKESAD50]

Thanks Mark

[MIKESAD50]

Well got the truck back from the exhaust shop today.
Drove it from exhaust shop to my shop about 3 miles.
Runs like S**t, loading up. not sure what is going on, may be fuel pressure or vacuum leak, not sure will hook up scanner and see if I can find out problem, should idle nice and smooth, but it aint.

It sure was fun driving it though, never made it over about 30mph.

Here is a link to You Tube videos. videos taken by my girlfriend Will post a picture of exhaust in the next few days.

https://youtu.be/6HPX2ZoeoUs

https://youtu.be/s-P_ngiQZXI

[mongocanfly]

Nice to see it running..you'll figure it out...trucks lookin good

[iowaboynca]

does look good under its own power.

[solidaxel]

Vacuum leak, MAF, O2, exhaust leak before O2, flange gasket, missing ground connection
Keep us updated on the problem solving, I am about a week out from starting my new LS3
and following your updates

[ptc]

Looks great!!!! nice to have on the road!

[MIKESAD50]

finished exhaust. may coat it or VHT high temp paint.

[Kansas T]

Originally Posted by MIKESAD50

Well got the truck back from the exhaust shop today.
Drove it from exhaust shop to my shop about 3 miles.
Runs like S**t, loading up. not sure what is going on, may be fuel pressure or vacuum leak, not sure will hook up scanner and see if I can find out problem, should idle nice and smooth, but it aint.

How about posting a pic of you air intake pipe and MAF sensor location. Those crate engines are very touchy about MAF placement. I've been through it on several builds. If the MAF is to close to the throttle body they load up and run terrible.

[MIKESAD50]

I'll take a picture tomorrow morning and post it.
Hooked scan tool up this morning and O2 voltages on both banks KOEO is 415mv and KOER O2 voltage is down to 10mv. Running really rich and fuel pressure is up close to 80psi.
I'm just ordered a Holley filter regulator assembly to try and bring pressures down.
I tried to keep the MAF away from the throttle and it is in a straight pipe section.

[solidaxel]

Originally Posted by MIKESAD50

I'll take a picture tomorrow morning and post it.
Hooked scan tool up this morning and O2 voltages on both banks KOEO is 415mv and KOER O2 voltage is down to 10mv. Running really rich and fuel pressure is up close to 80psi.
I'm just ordered a Holley filter regulator assembly to try and bring pressures down.
I tried to keep the MAF away from the throttle and it is in a straight pipe section.

Did you have the Air Cleaner on the end of the tube?

[MIKESAD50]

here is the intake system

[MIKESAD50]

Solidaxel,
I dont recall, what fuel pump system are you running with you LS3?

[solidaxel]

I am using a Camaro/Firebird in tank and a Wix filter
My instructions that came with the crate said to be 12 to 14" from the throttle, and it looks like you have that
How is the idle, does it "smell" "OK"

[MIKESAD50]

It smells really rich. not chugging black smoke but ricchhh.

[Kansas T]

The high fuel pressure could be a lot of it. The spec is about 60psi. solidaxel is right about what GM says in the instructions. I talked with GM tech support and their recommendation is to have at least 10 to 12 inches of straight pipe after the MAF sensor and the sensor needs to be installed in the top of the pipe. I would recommend moving your sensor closer to the air filter.

[mongocanfly]

80 psi does sound extremely high...
On my ls3 I'm going to run a areomotive 340 on it...I was told that would work fine..
On my lq9 my maf is right at the throttle and it causes no issues..my dyno man said it was fine.. on my ls3 I've got all the camaro breather system but I'm not sure how far away it is but I don't think its 12"...would have to measure to be sure though

[Kansas T]

Originally Posted by mongocanfly

80 psi does sound extremely high...
On my ls3 I'm going to run a areomotive 340 on it...I was told that would work fine..
On my lq9 my maf is right at the throttle and it causes no issues..my dyno man said it was fine.. on my ls3 I've got all the camaro breather system but I'm not sure how far away it is but I don't think its 12"...would have to measure to be sure though

Your probably not using GM's connect and cruise system on the LQ9. It seems to have a lot more trouble with MAF placement than some of the other computer systems.

[joedoh]

the LS3 fuel rail is returnless, depending on what you have used for a fuel pump and filter it sounds like maybe you are just hitting full pressure of the pump (80 psi) instead of what the returnless regulator at the filter sets it (60 psi).

I didnt read back through for what you used for a fuel pump and filter but thats just an observation.

[mongocanfly]

I had to look up what connect and cruise was....so no ...i guess I didn't use that..mines a junkyard lq9 with psi harness and stock ecm

[mongocanfly]

Mike I saw in post 64 the pic of your filter mounted on the rail....did you double check to make sure your pressure and return hoses are in the right place?...you may know already but pressure goes on the outside and return is in the middle..just asking..

[solidaxel]

Did I read on here somewhere where someone had the in and our (return) transposed on the fuel filter?

[mongocanfly]

Yep... that's happened a couple times on here recently....

[solidaxel]

,,,,,,,,,,,,, or maybe it was a restriction in the return line at the tank that made the fuel pressure so high

[MIKESAD50]

Guys,
Thank you all for the suggestions.
Mongocanfly, I did double check that I have the feed to the outside connection and return on the center connection.

Joedoh, I'm running a Aeromotive 340 Stealth in tank system, to the corvette filter than off to the fuel rails which have been set up returnless, they are Holley fuel rails but that shouldnt matter.
My thinking is the pressure and volume is overwhelming the filter/regulator., I was also thinking that maybe the return being only -6 might be restricting the return flow.
I will update as soon as I having this thing purring like it should be.

Solidaxel, I have not checked the return line from the filter to the tank yet. Its on my list to check when I get some time to look further into it.