running rich after head job
running rich after head job
Okay so heres the deal, I had a blow headgasket due to overheating. Headgasket replaced head milled problem solved. now heres the issue
Before the BHG I was runnign at +50 on my SAFC at 16 psi. After the headgasket replacement I am running at -30 on the SAFC, go figure. I am very nervous that now all of a sudden I am running so much richer and have not idea why.
Symptom 2
Now this is just a posssible symptom. On my boost controller I was at about 38% to run at 16 psi before the BHG now I am at 50% to run 16psi and I have no idea why I have to dial the controller up so much higher to obtain the same boost.
Now one possible answer is that before the bhg it was winter and around 40 degrees, so I guess it is possible that since now it is 85-90 degreees out that the teimp is what is creating the need to turn the boost controller up to obtain the same boost level. But again it makes me nervous not to know or understnad why.
P.S. yes I know I have mispellings
does anyone have any suggestions as to what may be going on?
Before the BHG I was runnign at +50 on my SAFC at 16 psi. After the headgasket replacement I am running at -30 on the SAFC, go figure. I am very nervous that now all of a sudden I am running so much richer and have not idea why.
Symptom 2
Now this is just a posssible symptom. On my boost controller I was at about 38% to run at 16 psi before the BHG now I am at 50% to run 16psi and I have no idea why I have to dial the controller up so much higher to obtain the same boost.
Now one possible answer is that before the bhg it was winter and around 40 degrees, so I guess it is possible that since now it is 85-90 degreees out that the teimp is what is creating the need to turn the boost controller up to obtain the same boost level. But again it makes me nervous not to know or understnad why.
P.S. yes I know I have mispellings
does anyone have any suggestions as to what may be going on?
Eidt tihs psot frist tehn we can hlep you out buecase I cna't raed atynihg you wtore. Just kidding but it's crazy how even if the first and last letters are in place you can still read what's written. Tricky that human brain. Oh, as far as your question, sorry man I don't know much about turbos just that they make you go faster.
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Joined: Aug 2004
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From: Nevada
How much did they mill the head?
When they mill your head your effective Compression Ratio goes up.
I would think you might need more fuel to prevent knock.
Dont have a for sure answer cause I have never dealt with the AFC before but I'm a little stumped.
When they mill your head your effective Compression Ratio goes up.
I would think you might need more fuel to prevent knock.
Dont have a for sure answer cause I have never dealt with the AFC before but I'm a little stumped.
Morris,
What size injectors are you running and are you running a stock fuel pump. My entire experience with FI was that I was running waaay too rich with 440's and a 255 Walbro. So before you had your HG problem you were running as lean as the SAFC will allow.
On the basis of adding 50% fuel did you have a solid 12:1 or what did you line look like??
Did you do any fuel changes between the HG fix - resulting in going from adding 50% to having to pull 30%?? When did you add your FPR??
Jonny
What size injectors are you running and are you running a stock fuel pump. My entire experience with FI was that I was running waaay too rich with 440's and a 255 Walbro. So before you had your HG problem you were running as lean as the SAFC will allow.
On the basis of adding 50% fuel did you have a solid 12:1 or what did you line look like??
Did you do any fuel changes between the HG fix - resulting in going from adding 50% to having to pull 30%?? When did you add your FPR??
Jonny
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Joined: May 2001
Posts: 2,465
Likes: 0
From: Illinois
I'm usually running around poor after a head job but that's another story. 
I too am surprised that you were at +50 before. That would seem to be very rich. What do your A/F ratios look like now?
I too am surprised that you were at +50 before. That would seem to be very rich. What do your A/F ratios look like now?
Well we only milled it enougth to make sure that it wasnt going to be warped. at the+ 50 I was at 12.2, I wanted to add more boost but could not becasue the injectors did not seem large enought to flwo enough fuel to support more boost. My guess is that the Fuel pressure somewhere along the line got dialed up some and that this is what is causeing me to have to pull fuel now. But it seems to be runing okay so I will probably just choose not to worry about it too much. I just would feel better if I knoew for sure what caused the change. It has been about 4 months since the car went down to me getting it back so I my reccollection could be faulty I guess.
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