I must have a crummy vacuum pump lol, only vacuum.. Well, at least we know where to get a new oil sender if the KB unit goes bad, the Chevy oil sender I think is a little longer, but would still work and same thread. Maybe it off of a chevette or pontiac or something.
KB BAP anyone having trouble????
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Really? Mine is a cheap plastic one but you can connect the hose to the "outlet" side of pump for pressure, guess I assumed most had this ability
. I cant imagine the switches are too expensive or hard to find. Is there any numbers or anything on yours? Manufacturer stamped on it or anything?No, no part numbers at all. I just recognize it as the GM design. I know the 70's Chevy v8 is the same except the shaft is slightly longer, but it would work.
It's all about sharing information, thanks guys for the help. Now when I call KB in the morning I have an idea of what I am talking about. On the other site I have been asking if anyone is running thiers man. with the control knob and if so what are your start and run setttings. I have 0 to 30 to wide open.........help.
I am set at max 50% with 21 lbs 2 1/2" pulley, before the belt slip after replacing the belt at the dyno shop, first run the A/F was perfect with the KB chip. Second run screaded the belt lol..
I had my car retuned yesterday at a different facility and was told under boost the fuel pressure is not increasing and causing a dip in my tq graph. It doesn't increase on the dyno, but on the streets, it goes from 30 psi to 55 psi under boost. WTF?
KB said to hook up the BAP. I have the Diablosport chip. Shadowgray03, I know you say it's safer to have the BAP, but adding the BAP will not increase fuel pressure with a Diablo chip? The car was tuned by Willie at Diablosport's facility, so I realy doubt it's the tune. (They felt it was something else going on and not the tune) If the chip can't increase pressure, what could be the issue? Or the fix?
KB said to hook up the BAP. I have the Diablosport chip. Shadowgray03, I know you say it's safer to have the BAP, but adding the BAP will not increase fuel pressure with a Diablo chip? The car was tuned by Willie at Diablosport's facility, so I realy doubt it's the tune. (They felt it was something else going on and not the tune) If the chip can't increase pressure, what could be the issue? Or the fix?
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There seems to be a big misunderstanding of how the BAP works. First off, the EEC has no idea the BAP even exists. The EEC knows what the fuel pumps flow and it also monitors fuel pressure. The Fuel Pump Driver Module(FPDM) is directed by the EEC and controls voltage going to the fuel pumps. It knows how much to send based on sensors in the car, engine load, pump flow characteristics etc. However the EEC also monitors pressure instead of just replying on its info to command the pumps. What happens is under boost the BAP steps up voltage to the fuel pumps increasing output. Since the Diablo chip does not allow for an increase in pressure the EEC lowers the duty cycle on the FPDM until normal pressure is seen. In a tune like Diablo's that doesnt "USE" the BAP it can still play an important part of the equation. Since the FPDM can be maxed with the KB@17psi the BAP kicks in, pressure increases, EEC see's increase and cuts duty cycle. What this does is give us a little more headroom as far as the FPDM duty cycle is concerned.
If your car is falling on its face at 3k rpm though, im not sure what thats caused by.
Got to talk about this chip and fuel pressure, are you saying Diablo does not increase fuel pressure?????????
I borrowed my autotap to a friend so I have yet to log mine, but my understanding is that the diablo does not utilize increased pressure like the KB chip does. im not sure how they accomplish adding more fuel, perhaps they just increase injector duty cycle.
Well... The shop worked on the car for a few more hours today and this is what's going on.
After hooking up the boost a pump, the fuel gauge is seeing more pressure, but it still gets dips in the dyno graph. We took OUT the Diablo chip and the car makes more power, at this point. We made 501 rwhp 580 torque@ 4500 RPM with just the BAP. (Was told it's not lean due to the BAP) At this RPM, the rwhp is up 40 and the torque is up 100. They are trying to get the graph to look good at 2000-4500 rpm before taking her up to 6200 RPM, which I think is very smart.
The boost bypass valve is loose too and will be tightened down Thursday. The bypass might be leaking hot air in under boost and causing my power loss. We'll figure out what to do with the chip tomorrow.
The car does not like to be hot either. 1 pull on the dyno is good, but the temperature in the motor gets to 201 on the second pull and the dips in the dyno show bad. ...And the pull was only to 4500 rpm! Why am I in Florida??? I'll put a 160 thermostat in tomorrow.
This is a Mustang dyno and different then what I dyno'ed on before (DynoJet), so after this shop finishes working on the car, I'll dyno on the same dyno as before to see what the results are.
Shadowgray03, thanks for the info and you're correct. So far with the BAP, the graph looks a tad better, but very similar with or without the BAP with the Diablo chip.
After hooking up the boost a pump, the fuel gauge is seeing more pressure, but it still gets dips in the dyno graph. We took OUT the Diablo chip and the car makes more power, at this point. We made 501 rwhp 580 torque@ 4500 RPM with just the BAP. (Was told it's not lean due to the BAP) At this RPM, the rwhp is up 40 and the torque is up 100. They are trying to get the graph to look good at 2000-4500 rpm before taking her up to 6200 RPM, which I think is very smart.
The boost bypass valve is loose too and will be tightened down Thursday. The bypass might be leaking hot air in under boost and causing my power loss. We'll figure out what to do with the chip tomorrow.
The car does not like to be hot either. 1 pull on the dyno is good, but the temperature in the motor gets to 201 on the second pull and the dips in the dyno show bad. ...And the pull was only to 4500 rpm! Why am I in Florida??? I'll put a 160 thermostat in tomorrow.
This is a Mustang dyno and different then what I dyno'ed on before (DynoJet), so after this shop finishes working on the car, I'll dyno on the same dyno as before to see what the results are.
Shadowgray03, thanks for the info and you're correct. So far with the BAP, the graph looks a tad better, but very similar with or without the BAP with the Diablo chip.
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regarding the boost bypass valve, i think racerat had an issue where the valve was partially open.
can anyone post a pic so i can inspect mine? ... i just don't know where to begin.
can anyone post a pic so i can inspect mine? ... i just don't know where to begin.
A couple people have had issues with the bypass. Its in a very hard to reach, see spot on these cars. Its on the back side if the KB, there will be a blue hose (1.5-2" maybe) connected to it. If you look straight down from top of KB on pass side with car running you will see a small arm, if you blip the throtle via the TB you can see the arm operate the bypass. Some people have had the bypass rod come off and/or wedge so it wont close all the way.
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