boosted running rich
#17
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Somewhere in a box I should have the original chips and an AutoThority set. A new set of factory 24lb injectors were installed with the supercharger, as 24lb was what the setup had used previously. I was wondering if one of the supercharger sellers keeps on hand chips for their "stage 1" kits with 6psi and no intercooler and if so if that would be a good place to start. How the hell do you add pics? There used to be an attachment cick on thing that I cannot now find
#18
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Is this a new problem? Has the car ever ran correctly or has it always been this rich since the install of the kit?
There are a list of reasons why a car could be running that rich, with or without the supercharger.
Start with the basics
1. Check the vacuum lines going to the FPR's for fuel, it's a sign one (or more) is leaking
2. Check fuel pressure at idle
3. One injector could be stuck open or just spraying too much
4. LH could be wonkey
5. MAF could need a rebuild
The list goes on, none of these have anything to do with the supercharger.....
"I think it has an adjustable fuel pressure regulator if that would change anything"
- An adjustable fuel pressure regulator or an FMU? Big difference. If you have an adjustable FPR it could simply be turned up too high.....
If it has an FMU, those should not effect fuel at idle unless they are broken. If you have one of those "spaceship" looking ones, that could be the smoking gun. Those are incredibly unreliable and when they fail could hike up fuel pressure everywhere.
Way too many questions in this thread for you to answer before we can really be of any help. Photos of your engine should help.
There are a list of reasons why a car could be running that rich, with or without the supercharger.
Start with the basics
1. Check the vacuum lines going to the FPR's for fuel, it's a sign one (or more) is leaking
2. Check fuel pressure at idle
3. One injector could be stuck open or just spraying too much
4. LH could be wonkey
5. MAF could need a rebuild
The list goes on, none of these have anything to do with the supercharger.....
"I think it has an adjustable fuel pressure regulator if that would change anything"
- An adjustable fuel pressure regulator or an FMU? Big difference. If you have an adjustable FPR it could simply be turned up too high.....
If it has an FMU, those should not effect fuel at idle unless they are broken. If you have one of those "spaceship" looking ones, that could be the smoking gun. Those are incredibly unreliable and when they fail could hike up fuel pressure everywhere.
Way too many questions in this thread for you to answer before we can really be of any help. Photos of your engine should help.
#19
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No issues b4 supercharger. current situation since install. taken to another shop (well renowned in business over 30 yrs) to check over work, claimed it was fine except for loose belt on supercharger...another grand thrown away
#20
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It appears you've uploaded the photos to your photo gallery, not this thread. So here they are:
#21
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Thank You! I'm horrible with tech stuff. And thank you to all who are trying to help with my issue. This site is a wealth of knowledge. I'll try and find the pics of the items I bought with the supercharger. A search of supercharger for sale might get a link. Thanks again
#22
Right, so same FMU as my supercharged 84. Please check factory pressure regulators for fuel on the vacuum line side, or even vacuum line on FMU (silver mushroom on the driver fire wall) for fuel. 5 minute quick check. It's happened twice on mine, same symptoms. Aging factory fuel pressure regulators giving up under increased pressure.
#23
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I'm not a fan of that regulator. Hours on the dyno testing more than one, they all went into the trash. The "selling point" of the BEGI is adjustability, which is a great idea on the bar napkin, it was never consistent enough for my tastes and actually locked up a couple of time (causing a spike in fuel pressure) this happened with each one I tested, wasn't a fluke. Maybe newer units are better, this was 15+ years ago.
You have a fuel pressure gauge (You'll soon be told that's a fire hazard) but at least you can check fuel pressure at idle - report back with that information.
Pull the vacuum line off the BEGI and report back what that fuel pressure is
After that, my first post still stands.....and reflects what Mike said
Start with the basics
1. Check the vacuum lines going to the FPR's for fuel, it's a sign one (or more) is leaking
2. Check fuel pressure at idle
3. One injector could be stuck open or just spraying too much
4. LH could be wonkey
5. MAF could need a rebuild
If aftermarket chips are installed, the tune on that could be suspect. A setup such as yours should be able to run with stock chips, adding fuel pressure under boost. Not idea since you'll be at stock timing (some vendors thinks this is OK to still be selling kits like this in 2018). However.....I see your intake air temp sensor is just before the MAF. This means it's probably seeing high enough temps all over to reduce timing to whatever the MAX retard is (unless someone monkeyed with the tune to change this). That could be enough to save your engine without a proper tune.
As to your previous question about chips from any vendor, the MURF928 setup is the only custom tuned 85/86 setup out there that I'm aware of using the stock brains, but there are too many variables to safely say "Here, use these chips". Not to mention those chips are designed to run with 42lb injectors and a modified MAF.
Again, this is only a partial list. The MAF is a wear item so maybe reach out to Roger and get the info on a rebuilt unit since it's inevitable that will need to be done sooner than later. Might as well start fresh so it's a known good unit.
My gut tells me the primary issue is around how the BEGI is adjusted assuming it's even working as intended.
Are the stock two fuel pressure regulators still installed or is one of them adjustable too???
We learned a 90 degree elbow without a diffuser isn't the best idea either, but I doubt that would be causing a rich idle.
At idle is there a lot of air coming out of the BOV?
You have a fuel pressure gauge (You'll soon be told that's a fire hazard) but at least you can check fuel pressure at idle - report back with that information.
Pull the vacuum line off the BEGI and report back what that fuel pressure is
After that, my first post still stands.....and reflects what Mike said
Start with the basics
1. Check the vacuum lines going to the FPR's for fuel, it's a sign one (or more) is leaking
2. Check fuel pressure at idle
3. One injector could be stuck open or just spraying too much
4. LH could be wonkey
5. MAF could need a rebuild
If aftermarket chips are installed, the tune on that could be suspect. A setup such as yours should be able to run with stock chips, adding fuel pressure under boost. Not idea since you'll be at stock timing (some vendors thinks this is OK to still be selling kits like this in 2018). However.....I see your intake air temp sensor is just before the MAF. This means it's probably seeing high enough temps all over to reduce timing to whatever the MAX retard is (unless someone monkeyed with the tune to change this). That could be enough to save your engine without a proper tune.
As to your previous question about chips from any vendor, the MURF928 setup is the only custom tuned 85/86 setup out there that I'm aware of using the stock brains, but there are too many variables to safely say "Here, use these chips". Not to mention those chips are designed to run with 42lb injectors and a modified MAF.
Again, this is only a partial list. The MAF is a wear item so maybe reach out to Roger and get the info on a rebuilt unit since it's inevitable that will need to be done sooner than later. Might as well start fresh so it's a known good unit.
My gut tells me the primary issue is around how the BEGI is adjusted assuming it's even working as intended.
Are the stock two fuel pressure regulators still installed or is one of them adjustable too???
We learned a 90 degree elbow without a diffuser isn't the best idea either, but I doubt that would be causing a rich idle.
At idle is there a lot of air coming out of the BOV?
#24
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Upon startup A/F is 15.3 for a few seconds, 11.2 for a few seconds, settles in at 11.6 Pressure gauge has a black range and a red range on the gauge. Fuel press reds 200/30 on the two dials, not sure which is what. Underneath the aluminum spaceship thing, it appears to have other regulators under it, one on each side. Spaceship has two blue lines on the lower side and one black line on the top side. Please remember I'm clueless. Figured FPR is Fuel Pressure Regulator, what is BEGI and BOV? Found the old paperwork. I bought the setup from a lister "Temekun" who bought it from "Cosmo Cramer" but never installed it. On cosmo cramer's car it made 370hp/344tq on his '85. It seems to be the old F.A.S.T. kit if that info helps at all. Thread states that "Ted" sorted it out back then (2013). The thing runs great and pulls like a freight train. I'm just scared that running too rich that it is not getting lubricated properly so I'm afraid to drive it. Could be I'm just a flake and shouldn't be so worried.
#26
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Since you state that you are 'cluless', and there's nothing wrong with that, then I'd recommend taking it to someone who understands forced induction.
This stuff is not easy even for an experienced person, and almost impossible for anyone else.
This stuff is not easy even for an experienced person, and almost impossible for anyone else.
#27
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As stock Fuel pressure at idle on an 85/86 is around 32PSI, I'd say the 30 mark is about correct (not the 200dial).
The BEGI is the spaceship thing on the Firewall (that is about to take your wallet to Alpha Centauri) if it is not working and needs to be serviced at a shop rates.
It raises the FP only under Boost if set up correctly, and does not affect Idle and non-boosted running.
The BOV is a Blow Off Valve, it opens when you back off the throttle when you have been under boost, giving the Boosted Intake pressure somewhere to go as the Throttle is now closed (gas peddle was released).
It can be seen in the second pic, lower left, next to all the wiring and a fuse holder (its black with a vacuum line connected).
Depending on shop rates, $1k is not way out there to change the SC belt (to just re-tighten, yeah a bit high) , as it is not easy to get to being the closest to the engine block.
You need to do some reading and educate yourself on SC cars and how they work, else you will continue to spend big $, training others that do not.
And where are you located, I think I missed that?
Dave K
The BEGI is the spaceship thing on the Firewall (that is about to take your wallet to Alpha Centauri) if it is not working and needs to be serviced at a shop rates.
It raises the FP only under Boost if set up correctly, and does not affect Idle and non-boosted running.
The BOV is a Blow Off Valve, it opens when you back off the throttle when you have been under boost, giving the Boosted Intake pressure somewhere to go as the Throttle is now closed (gas peddle was released).
It can be seen in the second pic, lower left, next to all the wiring and a fuse holder (its black with a vacuum line connected).
Depending on shop rates, $1k is not way out there to change the SC belt (to just re-tighten, yeah a bit high) , as it is not easy to get to being the closest to the engine block.
You need to do some reading and educate yourself on SC cars and how they work, else you will continue to spend big $, training others that do not.
And where are you located, I think I missed that?
Dave K
Last edited by davek9; 09-15-2018 at 06:45 PM.
#28
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I'm in. Kansas City, Mo....., l'm capable of pulling to check plugs, pull a vacume line to see if fuel runs out, plug a line, smell, listen to a part. I by NO means consider myself a mechanic. Can anyone tell me if it will damage the engine to run this rich
#30
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I'm still in the, Pull the plugs camp,
I'll bet she is all loaded up from Cold starts, and then shutdowns before the engine had a chance to clear the Cold start mixture.
Your most likely running on 7 Cyl, and that will give you the same AFR results you are seeing.
Put in new Bosch plugs, one range colder that stock.
Dave K
I'll bet she is all loaded up from Cold starts, and then shutdowns before the engine had a chance to clear the Cold start mixture.
Your most likely running on 7 Cyl, and that will give you the same AFR results you are seeing.
Put in new Bosch plugs, one range colder that stock.
Dave K