Would appreciate some tuning advice for new 2056, Having trouble dialing in the AFR Options

[rbzymek]

So I replaced the 1.8L with a SCAT 2056 long block with a Web 73 cam and 42x38 valves. They provided 4 bolt (intake) heads so I could use the 1.8 tin and carry over L-Jet system. The CR is 8.5 and I have an adjustable FPR. The injectors are stock 1.8L L-Ject. I can dial in the idle AFR easily but I get rich 9.0 AFR on very light tip in. I also go lean at higher speeds (>4000). I suspect the static is set too high on the AFM. Any suggestions?

[djway]

When trying to get the old tired 1.8 to run I just jumped on the freeway while watching the gauge under load then at cruise.
I would get off the freeway and adjust the spring pressure then hop back on the freeway.
I kept doing it until the numbers looked acceptable.
In my case it was dumping too much fuel so I tightened the spring.

[rbzymek]

When trying to get the old tired 1.8 to run I just jumped on the freeway while watching the gauge under load then at cruise.
I would get off the freeway and adjust the spring pressure then hop back on the freeway.
I kept doing it until the numbers looked acceptable.
In my case it was dumping too much fuel so I tightened the spring.

Good plan. I have some FJ707 injectors on order which are replacements for 2.0 912 with L-Jet. I also have a fuel pressure regulator coming which is supposed to be for a 1.8 914 which should be 35 psi. All of the other FPR's I purchased are 40-42 psi. I will install the correct parts and give it a try.

[rbzymek]

When trying to get the old tired 1.8 to run I just jumped on the freeway while watching the gauge under load then at cruise.
I would get off the freeway and adjust the spring pressure then hop back on the freeway.
I kept doing it until the numbers looked acceptable.
In my case it was dumping too much fuel so I tightened the spring.

Good plan. I have some FJ707 injectors on order which are replacements for 2.0 912 with L-Jet. I also have a fuel pressure regulator coming which is supposed to be for a 1.8 914 which should be 35 psi. All of the other FPR's I purchased are 40-42 psi. I will install the correct parts and give it a try.

Clay,
I installed the FJ707 General injectors and the Beck Arnley 158-0073 FPR both of which reference a 2.0L 912 engine. Engine off pushing the fuel flap I get 41 psi on the gauge. It shows about 34 psi gauge at idle with the vacuum compensation. After a good warm up run I adjusted the AFM to get 13.5 at idle and about 12- 12.5 at WOT. My RPM limit is 4000 RPM unlit after break in. The throttle body is a 45mm bus unit. The bad news is that I get 8.5 to 10.5 AFR at part throttle tip in with some rich misfire. Heavy crowd is 13-13.5. If I tighten the AFM then I get 15-18 AFR at idle---no good. I think the fuel pressure is too high but this is about the third FPR that I have tried. Another issue is that I cannot get the idle below 1200 even with the TB screw all the way in. (need to see if there is a hole in the plate.) I looked for leaks and even plugged the air bypass hose. I used rubber cement on the runner hose sleeves and Permatex on the intake gaskets. Timing is set at 7 degrees with the vacuum hose off. Any suggestions would be appreciated.
Regards,
Ray

[ClayPerrine]

When trying to get the old tired 1.8 to run I just jumped on the freeway while watching the gauge under load then at cruise.
I would get off the freeway and adjust the spring pressure then hop back on the freeway.
I kept doing it until the numbers looked acceptable.
In my case it was dumping too much fuel so I tightened the spring.

Good plan. I have some FJ707 injectors on order which are replacements for 2.0 912 with L-Jet. I also have a fuel pressure regulator coming which is supposed to be for a 1.8 914 which should be 35 psi. All of the other FPR's I purchased are 40-42 psi. I will install the correct parts and give it a try.

Clay,
I installed the FJ707 General injectors and the Beck Arnley 158-0073 FPR both of which reference a 2.0L 912 engine. Engine off pushing the fuel flap I get 41 psi on the gauge. It shows about 34 psi gauge at idle with the vacuum compensation. After a good warm up run I adjusted the AFM to get 13.5 at idle and about 12- 12.5 at WOT. My RPM limit is 4000 RPM unlit after break in. The throttle body is a 45mm bus unit. The bad news is that I get 8.5 to 10.5 AFR at part throttle tip in with some rich misfire. Heavy crowd is 13-13.5. If I tighten the AFM then I get 15-18 AFR at idle---no good. I think the fuel pressure is too high but this is about the third FPR that I have tried. Another issue is that I cannot get the idle below 1200 even with the TB screw all the way in. (need to see if there is a hole in the plate.) I looked for leaks and even plugged the air bypass hose. I used rubber cement on the runner hose sleeves and Permatex on the intake gaskets. Timing is set at 7 degrees with the vacuum hose off. Any suggestions would be appreciated.
Regards,
Ray

The fuel pressure is a little high. What fuel pump are you using?

Also, you might want to try an AFM that has not been opened up. And also replace the gaskets in the oil filler cap. If they are bad,they will cause a false air issue, and make the car run bad. If someone that didn't know any better changed the AFM to compensate for the bad oil cap seals, you can get all kinds of screwy mixtures.

Clay

[porschetub]

When trying to get the old tired 1.8 to run I just jumped on the freeway while watching the gauge under load then at cruise.
I would get off the freeway and adjust the spring pressure then hop back on the freeway.
I kept doing it until the numbers looked acceptable.
In my case it was dumping too much fuel so I tightened the spring.

Good plan. I have some FJ707 injectors on order which are replacements for 2.0 912 with L-Jet. I also have a fuel pressure regulator coming which is supposed to be for a 1.8 914 which should be 35 psi. All of the other FPR's I purchased are 40-42 psi. I will install the correct parts and give it a try.

Clay,
I installed the FJ707 General injectors and the Beck Arnley 158-0073 FPR both of which reference a 2.0L 912 engine. Engine off pushing the fuel flap I get 41 psi on the gauge. It shows about 34 psi gauge at idle with the vacuum compensation. After a good warm up run I adjusted the AFM to get 13.5 at idle and about 12- 12.5 at WOT. My RPM limit is 4000 RPM unlit after break in. The throttle body is a 45mm bus unit. The bad news is that I get 8.5 to 10.5 AFR at part throttle tip in with some rich misfire. Heavy crowd is 13-13.5. If I tighten the AFM then I get 15-18 AFR at idle---no good. I think the fuel pressure is too high but this is about the third FPR that I have tried. Another issue is that I cannot get the idle below 1200 even with the TB screw all the way in. (need to see if there is a hole in the plate.) I looked for leaks and even plugged the air bypass hose. I used rubber cement on the runner hose sleeves and Permatex on the intake gaskets. Timing is set at 7 degrees with the vacuum hose off. Any suggestions would be appreciated.
Regards,
Ray

The fuel pressure is a little high. What fuel pump are you using?

Also, you might want to try an AFM that has not been opened up. And also replace the gaskets in the oil filler cap. If they are bad,they will cause a false air issue, and make the car run bad. If someone that didn't know any better changed the AFM to compensate for the bad oil cap seals, you can get all kinds of screwy mixtures.

Clay

(IMG:style_emoticons/default/agree.gif) keep it all stock and don't add lots of changes till you get to a point where you don't know what is working or not.
Stock injectors and afm will flow to what ever displacement change is made,increased fuel pressure has no effect and is not required ,an adjustable FPR will sort that.
I don't know about the cam you have and how it works with your big valve heads you have with the L-jet,if the AFM wiper is bouncing around @ idle there is little you can do ,can indicate poor vacuum signal ,but do check for air leaks as this system has no tolerance for them.
Good luck.

[rbzymek]

When trying to get the old tired 1.8 to run I just jumped on the freeway while watching the gauge under load then at cruise.
I would get off the freeway and adjust the spring pressure then hop back on the freeway.
I kept doing it until the numbers looked acceptable.
In my case it was dumping too much fuel so I tightened the spring.

Good plan. I have some FJ707 injectors on order which are replacements for 2.0 912 with L-Jet. I also have a fuel pressure regulator coming which is supposed to be for a 1.8 914 which should be 35 psi. All of the other FPR's I purchased are 40-42 psi. I will install the correct parts and give it a try.

Clay,
I installed the FJ707 General injectors and the Beck Arnley 158-0073 FPR both of which reference a 2.0L 912 engine. Engine off pushing the fuel flap I get 41 psi on the gauge. It shows about 34 psi gauge at idle with the vacuum compensation. After a good warm up run I adjusted the AFM to get 13.5 at idle and about 12- 12.5 at WOT. My RPM limit is 4000 RPM unlit after break in. The throttle body is a 45mm bus unit. The bad news is that I get 8.5 to 10.5 AFR at part throttle tip in with some rich misfire. Heavy crowd is 13-13.5. If I tighten the AFM then I get 15-18 AFR at idle---no good. I think the fuel pressure is too high but this is about the third FPR that I have tried. Another issue is that I cannot get the idle below 1200 even with the TB screw all the way in. (need to see if there is a hole in the plate.) I looked for leaks and even plugged the air bypass hose. I used rubber cement on the runner hose sleeves and Permatex on the intake gaskets. Timing is set at 7 degrees with the vacuum hose off. Any suggestions would be appreciated.
Regards,
Ray

The fuel pressure is a little high. What fuel pump are you using?

Also, you might want to try an AFM that has not been opened up. And also replace the gaskets in the oil filler cap. If they are bad,they will cause a false air issue, and make the car run bad. If someone that didn't know any better changed the AFM to compensate for the bad oil cap seals, you can get all kinds of screwy mixtures.

Clay

(IMG:style_emoticons/default/agree.gif) keep it all stock and don't add lots of changes till you get to a point where you don't know what is working or not.
Stock injectors and afm will flow to what ever displacement change is made,increased fuel pressure has no effect and is not required ,an adjustable FPR will sort that.
I don't know about the cam you have and how it works with your big valve heads you have with the L-jet,if the AFM wiper is bouncing around @ idle there is little you can do ,can indicate poor vacuum signal ,but do check for air leaks as this system has no tolerance for them.
Good luck.

Clay,
You were correct when asking about the fuel pump I am using. It turns out I installed a (cheap) MostPlus pump but turns out it is 5 Bar and 300 l/min as opposed to the correct one which is 2.5 Bar and about 167 l/min. I have ordered the correct Bosch replacement pump. I suspect that the MostPlus pump was swamping the bypass mechanism in the regulator. If there was no more range of authority in the regulator then at higher manifold vacuum like a light tip in the regulator cannot compensate for the vacuum which would cause excessive fuel flow at high manifold vacuum. Hence the 8.5 to 9.0 AFR on tip in. More to follow.