boost spike to 1.6bar on 91 :-O
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boost spike to 1.6bar on 91 :-O
So I just installed my defi bf boost gauge. Everything is working perfectly, seems to be fine! I see a solid 1.3-1.35 bar of boost at WOT through each gear, maybe touching 1.4 in 4th and 5th. Sounds normal right?
If I downshift from 5th -> 4th or 4th -> 3rd and go WOT (I rev match if that matters here) I will see 1.5-1.6 bar EVERY time. It's insane. I don't hear/feel/see any knock or fuel cut or anything but I mean, damn!
Currently I'm running the HKS RS intake, stock d/v, stock downpipe, works HFC, megan racing catback. Haven't touched the boost solenoid or anything, but I am planning to install my buschur MBC tomorrow.
Additionally, stock as the boost should be, I see little to no taper at all ...
It all seems too good to be true, what could be up?
If I downshift from 5th -> 4th or 4th -> 3rd and go WOT (I rev match if that matters here) I will see 1.5-1.6 bar EVERY time. It's insane. I don't hear/feel/see any knock or fuel cut or anything but I mean, damn!
Currently I'm running the HKS RS intake, stock d/v, stock downpipe, works HFC, megan racing catback. Haven't touched the boost solenoid or anything, but I am planning to install my buschur MBC tomorrow.
Additionally, stock as the boost should be, I see little to no taper at all ...
It all seems too good to be true, what could be up?
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OK so I just did a 1st->2nd->3rd gear run. It's pretty cool outside, I'd say high 60's, no real humidity.
1st gear: peak to 1.3bar, taper almost immediately to 1.1 to shift
2nd gear: peak to 1.35-1.38bar, taper almost immediately to 1.1-1.2 to shift
3rd gear: peak to 1.4bar, taper slightly slower to 1.15-1.2
Now that sounds more like your normal evo right there... the taper doesn't seem to happen much in 4th/5th though, I presume this is due to engine load.
I'll do some more testing and report back if anything changes.
Still wondering about that 1.6bar spike though!
1st gear: peak to 1.3bar, taper almost immediately to 1.1 to shift
2nd gear: peak to 1.35-1.38bar, taper almost immediately to 1.1-1.2 to shift
3rd gear: peak to 1.4bar, taper slightly slower to 1.15-1.2
Now that sounds more like your normal evo right there... the taper doesn't seem to happen much in 4th/5th though, I presume this is due to engine load.
I'll do some more testing and report back if anything changes.
Still wondering about that 1.6bar spike though!
Well that MBC should help control the spiking, at the least.
If you haven't gotten a tune, do that. Also get a fuel pump for your mods. I'm using the Buschur MBC and I recently installed my Defi BF and saw that I spiked at 1.6bar(23psi) although I set it for 1.5bar = 21psi. I guess my prior boost gauge might not have been that accurate, but you never know.
It's not bad since I do have the fuel pump, engine not fuel starved, but I lowered the boost a bit to peak and hold at 1.5bar. Before it would spike to 1.6bar at 4th/5th and hold at 1.5bar. I'm not too worried about it since it's tuned for the mods.
The MBC will help with the spiking, but honestly... you'd never really know how accure the gauge can be, BF or not.
If you haven't gotten a tune, do that. Also get a fuel pump for your mods. I'm using the Buschur MBC and I recently installed my Defi BF and saw that I spiked at 1.6bar(23psi) although I set it for 1.5bar = 21psi. I guess my prior boost gauge might not have been that accurate, but you never know.
It's not bad since I do have the fuel pump, engine not fuel starved, but I lowered the boost a bit to peak and hold at 1.5bar. Before it would spike to 1.6bar at 4th/5th and hold at 1.5bar. I'm not too worried about it since it's tuned for the mods.
The MBC will help with the spiking, but honestly... you'd never really know how accure the gauge can be, BF or not.
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From: San Jose, CA
Originally Posted by rsboy
Well that MBC should help control the spiking, at the least.
If you haven't gotten a tune, do that. Also get a fuel pump for your mods. I'm using the Buschur MBC and I recently installed my Defi BF and saw that I spiked at 1.6bar(23psi) although I set it for 1.5bar = 21psi. I guess my prior boost gauge might not have been that accurate, but you never know.
It's not bad since I do have the fuel pump, engine not fuel starved, but I lowered the boost a bit to peak and hold at 1.5bar. Before it would spike to 1.6bar at 4th/5th and hold at 1.5bar. I'm not too worried about it since it's tuned for the mods.
The MBC will help with the spiking, but honestly... you'd never really know how accure the gauge can be, BF or not.
If you haven't gotten a tune, do that. Also get a fuel pump for your mods. I'm using the Buschur MBC and I recently installed my Defi BF and saw that I spiked at 1.6bar(23psi) although I set it for 1.5bar = 21psi. I guess my prior boost gauge might not have been that accurate, but you never know.
It's not bad since I do have the fuel pump, engine not fuel starved, but I lowered the boost a bit to peak and hold at 1.5bar. Before it would spike to 1.6bar at 4th/5th and hold at 1.5bar. I'm not too worried about it since it's tuned for the mods.
The MBC will help with the spiking, but honestly... you'd never really know how accure the gauge can be, BF or not.
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