my boost problem solved!!!!!! yeay, beer for everyone!
05-10-06, 12:02 AM
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my boost problem solved!!!!!! yeay, beer for everyone!
Im jumping out of my skin right now, this is the first time since i bought the car 3 months ago that i truely felt the power!! my problem can be seen here:
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/still-boost-problems-calling-all-non-seq-fds-517966/
basically, i wouldnt see full boost on the stock non-sequential twins untill above 5000 rpms. shitty i know. on boost up i would hear a sskkwiish sskkwiish sskkwiish and then it would boost up. at 10 psi it would hold for about 1000 rpms then fall off. no matter what i turned the boost controller to it would fall off. today i got off my *** and started some actual diagnosing. i check the profect b if it was set right for internal WG, then i thought to check the sequential valve in the manifold, it should be off, the valve should be welded open as the other owner said.... i get under it and NO!!! its not only not welded, its not tied open,and it flaps when i blow on it its so loose!! so, i tied it open with a hanger wire, and then notice a bolt that goes in horizontally and hold part of the manifold together that leads to the rear turbine housing is loose.. or the nut was cause its a stud. THE MANFIDOLDS HAD A MILLIMETER GAP THAT WORKED ITS WAY OPEN LETTING HOT GASSES EXCAPE!!!so i get a ratchet and start to tighten to close the gap but the gap doesnt budge and the stud breaks. ****@!. doesnt matter, the manifold was wardped anyway... then i notice the heat sheild has burned clean through from the gasses escaping!!
well, after this i deside later on il change out manifolds or go single in a month because this isnt ganna fix without taking the turbos off. so i get things buttoned up and take her out for a spin. WOOOWW. this thing is fast as ****... even with a exhaust leak between the motor and turbos. and i see full boost by 3500 rpms. now were talking. i drive her around for a bit and get a race with a modified 01 mustang bullet. From a 2nd gear roll i run away FAST! i pull so hard ( like 15 car lengths) that i think he let off. he gets next to me and says " **** THATS FAST!, serisouly thats like, obsurd fast. you got a single on that?!" I say no, stock twins. but probably 340whp. this dude said that race he didnt let out of it at all.
remember guys, if you buy a modded car, never assume it was done right. i know the motor and fuel systems and stuff were done right because who installed them. but im ganna look through alot after this.
also, im having trouble with boost creep now and boost spikes. i see spikes nearing 14 psi while it holds at 12 psi. my profect b series 1 is set really low, like around 2/5ths turn on low setting, and less than a 1/4 balance. im ganna try and mess with the swtiches i the back because it says theres a setting for over boosting.
anywas, sorry to make this long, if you have these symptoms, and are non seq. looks at how the conversion was done, it may help your woes. btw, my mods are below:
mods are fuego racing built motor w/ atkins 2mm seals, mild street port.
non seq
fmic
greddy type s
fluidine rad
pulleys
supra pump
1600cc 2nds
aeromotiv fpr
PFC
greddy profect b
cltuch
lwfw
3.5 inch turbo back exhaust
twin intakes
etc, etc
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/still-boost-problems-calling-all-non-seq-fds-517966/
basically, i wouldnt see full boost on the stock non-sequential twins untill above 5000 rpms. shitty i know. on boost up i would hear a sskkwiish sskkwiish sskkwiish and then it would boost up. at 10 psi it would hold for about 1000 rpms then fall off. no matter what i turned the boost controller to it would fall off. today i got off my *** and started some actual diagnosing. i check the profect b if it was set right for internal WG, then i thought to check the sequential valve in the manifold, it should be off, the valve should be welded open as the other owner said.... i get under it and NO!!! its not only not welded, its not tied open,and it flaps when i blow on it its so loose!! so, i tied it open with a hanger wire, and then notice a bolt that goes in horizontally and hold part of the manifold together that leads to the rear turbine housing is loose.. or the nut was cause its a stud. THE MANFIDOLDS HAD A MILLIMETER GAP THAT WORKED ITS WAY OPEN LETTING HOT GASSES EXCAPE!!!so i get a ratchet and start to tighten to close the gap but the gap doesnt budge and the stud breaks. ****@!. doesnt matter, the manifold was wardped anyway... then i notice the heat sheild has burned clean through from the gasses escaping!!
well, after this i deside later on il change out manifolds or go single in a month because this isnt ganna fix without taking the turbos off. so i get things buttoned up and take her out for a spin. WOOOWW. this thing is fast as ****... even with a exhaust leak between the motor and turbos. and i see full boost by 3500 rpms. now were talking. i drive her around for a bit and get a race with a modified 01 mustang bullet. From a 2nd gear roll i run away FAST! i pull so hard ( like 15 car lengths) that i think he let off. he gets next to me and says " **** THATS FAST!, serisouly thats like, obsurd fast. you got a single on that?!" I say no, stock twins. but probably 340whp. this dude said that race he didnt let out of it at all.
remember guys, if you buy a modded car, never assume it was done right. i know the motor and fuel systems and stuff were done right because who installed them. but im ganna look through alot after this.
also, im having trouble with boost creep now and boost spikes. i see spikes nearing 14 psi while it holds at 12 psi. my profect b series 1 is set really low, like around 2/5ths turn on low setting, and less than a 1/4 balance. im ganna try and mess with the swtiches i the back because it says theres a setting for over boosting.
anywas, sorry to make this long, if you have these symptoms, and are non seq. looks at how the conversion was done, it may help your woes. btw, my mods are below:
mods are fuego racing built motor w/ atkins 2mm seals, mild street port.
non seq
fmic
greddy type s
fluidine rad
pulleys
supra pump
1600cc 2nds
aeromotiv fpr
PFC
greddy profect b
cltuch
lwfw
3.5 inch turbo back exhaust
twin intakes
etc, etc
Last edited by rt turbo; 05-10-06 at 12:19 AM.
05-10-06, 08:18 AM
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true, but less headaches. not so many hoses and solenoids to keep working in sinq. besides now i have a rediculous amount of wheel spin. i couldnt imagine a properly working seq. setup with my mods... 1st gear would be a 1/4 second. 
05-10-06, 10:35 AM
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Originally Posted by d1rx7
send beer to 2/18 blackwood st nelson nz. 
05-10-06, 11:55 AM
#7
For the boost creep problem, consider your flow mods:
FMIC, cat-back, intakes, and "etc etc". If the etc etc includes a midpipe and downpipe, then yeah, you NEED to remove those turbos and port the wastegate. Because you're simply outflowing the stock wastegate opening, which is why your ProfecB can't do much about it.
The other option is putting some restriction back into the system - a stock cat will usually do it.
Either way, you need to know what boost your PFC is tuned for and to watch that boost gauge. Or else your single turbo budget will become an engine rebuild budget. That would be sad and stupid.
Dave
FMIC, cat-back, intakes, and "etc etc". If the etc etc includes a midpipe and downpipe, then yeah, you NEED to remove those turbos and port the wastegate. Because you're simply outflowing the stock wastegate opening, which is why your ProfecB can't do much about it.
The other option is putting some restriction back into the system - a stock cat will usually do it.
Either way, you need to know what boost your PFC is tuned for and to watch that boost gauge. Or else your single turbo budget will become an engine rebuild budget. That would be sad and stupid.
Dave
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05-11-06, 02:45 PM
#8
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im tuned for 15 to 16 psi. the pfc records a peak which is a spike of .99mmhg, or 14psi. i watched the pfc and saw it holding around .83-.87 highest. so it doesnt go much over 13psi except for the spikes... and it still is below 16psi which I should be tuned for, and do have all supporting mods to run that. i never run over 14 psi unless i have half a tank of 100 octane. The autometer boost gauge seems to read around .5psi lower than the pfc shows. i guess either this gauge is wrong or the MAP sensor reads a tad high?
05-11-06, 03:00 PM
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ohh yeah, forgot to add, i do have a full 3.5" inch turboback exhaust...
I read on Greddy's site that you can set the rear of the profect b differently if you are overboosting. im thinking of trying that otehr setting and seeing how it goes. does anyone have any experience with changing those switches on the rear to cure overboosting?
I read on Greddy's site that you can set the rear of the profect b differently if you are overboosting. im thinking of trying that otehr setting and seeing how it goes. does anyone have any experience with changing those switches on the rear to cure overboosting?
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tiger18
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09-03-15 08:27 PM