speed limit defencer
03-26-09, 06:55 PM
#1
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speed limit defencer
ive had one in my car since i bought it but was recently told by a rx-7 mechanic that i should take it out for safety of my engine and that my car isnt set up for the higher revs and speed, my car basically stops pushing hard about 180km/hr isnt that stalk speed without a rev limitter,,,, and another question my horn starts honking by itself when i hit high revs hard (slammin gears) anyone know if thats just a factory sound or if somethings shorting? thx guys
03-26-09, 09:24 PM
#3
ive had one in my car since i bought it but was recently told by a rx-7 mechanic that i should take it out for safety of my engine and that my car isnt set up for the higher revs and speed, my car basically stops pushing hard about 180km/hr isnt that stalk speed without a rev limitter,,,, and another question my horn starts honking by itself when i hit high revs hard (slammin gears) anyone know if thats just a factory sound or if somethings shorting? thx guys
What kind of sensation are you experiencing when you hit the speed limiter. Do the rev's bounce slightly or does the car just stop pulling?
03-27-09, 04:13 AM
#4
Fuel Cut Defencer, FCD. It lies to the ecu about boost pressure when installing an aftermarket free flowing exhaust system. The FCD is part of the exhaust package sold by Racing Beat, the old HKS systems and others. An 87 TII should be able to hit 135 mph in 5th gear and not hit fuel cut.
The 'horn' you hear is the warning buzzer for rev limit. Warning goes off 6200-6800 rpm. Keep the tach under 7000-7500 rpm,. It will increase engine longevity and yield better ETs. A rotary can be built for much higher rpms, but stock ones aren't.
Not sure how 'special' your mechanic is, but I think that this is his way of telling you to back off hitting redline too much.
The 'horn' you hear is the warning buzzer for rev limit. Warning goes off 6200-6800 rpm. Keep the tach under 7000-7500 rpm,. It will increase engine longevity and yield better ETs. A rotary can be built for much higher rpms, but stock ones aren't.
Not sure how 'special' your mechanic is, but I think that this is his way of telling you to back off hitting redline too much.
03-27-09, 02:43 PM
#5
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i dont know when i hit the defencer ,, how could i tell... the car just stops pulling hard/basically stops excelling, the buzz is a horn,, like beep beep beeeeeeeeeeeeeeeep its acually my horn not a buzz is a horn suppost to go off? I do have 3" exhaust is that to big for a stock turbo setup... this engine is a jdm so i dont really know what they screwd up trying to put it in.
03-27-09, 02:48 PM
#6
the beep is the redline warning buzzer. It means shift up.
Does the car accelerate and then suddenly fall on it's face? That's fuel cut.
Does the car accelerate gradually until it stops pulling? That's your engine running out of power, probably due to a clogged cat.
Does the car accelerate and then suddenly fall on it's face? That's fuel cut.
Does the car accelerate gradually until it stops pulling? That's your engine running out of power, probably due to a clogged cat.
03-27-09, 03:05 PM
#7
A full 3" exhaust will cause boost creep issues on the stock wastegate. Fuel cut is at 8.6 psi, and under load in higher gears (3rd, 4th, 5th) you should be overwhelming the wastegate, which will increase boost right up to this pressure or higher. As mentioned, this will feel like hitting a wall since fuel is cut to rear rotor at this pressure level.
Do not just go buy a fuel cut defenser and throw that in. If your injectors and fuel pump are stock, you will likely overboost and blow the engine. Right now, that 8.6psi limit is harsh, but a good thing in that it's preventing 10-15 psi spikes.
The only real way to fix this is to get the wategate ported larger. If you don't have the means to do this, add some restriction back to the exhaust system.
Do not just go buy a fuel cut defenser and throw that in. If your injectors and fuel pump are stock, you will likely overboost and blow the engine. Right now, that 8.6psi limit is harsh, but a good thing in that it's preventing 10-15 psi spikes.
The only real way to fix this is to get the wategate ported larger. If you don't have the means to do this, add some restriction back to the exhaust system.
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03-27-09, 04:43 PM
#8
The best advice I can give you at present is to start spending hours/days reading through the 2nd gen tech and archive sections and learn everything you can about the turbo engines and how they are set up. From what it sounds like, your's may not last long if you continue to abuse it in the manner which you are.
As with any engine, there are rpm limits. What happens when you run a piston engine at 8k? While running a rotary at too high of an rpm may not fail quite as dramaticaly as it's boinger counterpart, the result is the same. Rotaries do not like overheating and turbo rotarys will NOT tolerate running lean or detonation.
The following links will lead you to the FSMs and other rotary related reading. These will come in handy if you continue driving/racing in the same manner as you have. Good Luck.
http://foxed.ca/foxed/index.php?page=rx7manual
http://www.wankel.net/~krwright/cars/rx7/manuals.html
As with any engine, there are rpm limits. What happens when you run a piston engine at 8k? While running a rotary at too high of an rpm may not fail quite as dramaticaly as it's boinger counterpart, the result is the same. Rotaries do not like overheating and turbo rotarys will NOT tolerate running lean or detonation.
The following links will lead you to the FSMs and other rotary related reading. These will come in handy if you continue driving/racing in the same manner as you have. Good Luck.
http://foxed.ca/foxed/index.php?page=rx7manual
http://www.wankel.net/~krwright/cars/rx7/manuals.html
03-27-09, 05:01 PM
#9
Former Moderator. RIP Icemark.
ive had one in my car since i bought it but was recently told by a rx-7 mechanic that i should take it out for safety of my engine and that my car isnt set up for the higher revs and speed, my car basically stops pushing hard about 180km/hr isnt that stalk speed without a rev limitter,,,,
Jspec cars are limited to 180km/hr. To fix the issue remove the instrument/gauge panel and remove the screw that is near the bottom left that says 180KM.
03-29-09, 11:22 PM
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its a lhd with a jdm engine i just did a compression test on it yesterday and i got 90-95 psi FR and 85-90 psi RR is that good,,, and why would one be more worn than the other do they just wear that way?
