Safe boost on Fc?
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Safe boost on Fc?
I have a stock 87 turbo fc.. with cat back and a fuel cut defender.. I was wondering what should i run boost wise if i wanted to turn it up a little and still be "reliable"
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the stock turbo fuel pump has no extra capacity. it is important that the filter both in the tank, and in the engine bay are new. also its a good idea to check the fuel pump voltage, if its too low, then the pump will not supply enough fuel. sometimes this even means redoing the charging system harness!
plan B is something like an FD fuel pump, if you've got a friend with an FD, just take his stock one, it'll be sitting around.
the stock precat/dp sucks, it creates a TON of backpressure, which is BAD for a rotary. however i used to see 13psi on cold days, and the STOCK S5's run 8.5psi @peak boost.
so if you have the fuel system sorted, 8.5psi is fine, 10psi is on the high side for stock fuel, it can be done, but you should be considering bigger injectors and or an ECU upgrade.
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"the stock turbo fuel pump has no extra capacity. it is important that the filter both in the tank, and in the engine bay are new. "
True that. Inexpensive maintenance yielding comparative high return
"also its a good idea to check the fuel pump voltage, if its too low, then the pump will not supply enough fuel. sometimes this even means redoing the charging system harness! " "plan B is something like an FD fuel pump"
1. Run a heavy gauge wire directly from the battery, 30 amp fuse in between, back to the fuel pump area. Cut the wire providing the stock "hot" to the pump and run it to the trigger side of the relay, the new "hot" to one side of the relay, other side to the wire running to the relay, and of course wire to the chassis to ground the other side of the relay trigger circuit. This will eliminate very common voltage drop the stock wiring will provide.
2. Agree, replace the stock fuel pump with one from an FD, or buy a Walbro or Denso aftermarket fuel pump. Very easy install process.
Goal for 1 & 2 is to help insure you don't lean out on your fuel. You lean out, pop does your engine. You might want to also invest in an EGT gauge or Wideband (narrow band that sources off the ECU is only good for entertainment value, not meaningful information) gauge so you can keep an eye on things so to avoid this dreaded leaning out.
Cat back by itself won't change boost, so I'm assuming you'll be installing a boost controller to up the boost. In the alternative, a RB downpipe and presilencer will get you to higher boost all by itself. Full REV II better still.
With all the above I'd still limit yourself to 7-8.5 lbs boost if you're running the stock ECU. But that should get you kissing 200 rwhp.
True that. Inexpensive maintenance yielding comparative high return
"also its a good idea to check the fuel pump voltage, if its too low, then the pump will not supply enough fuel. sometimes this even means redoing the charging system harness! " "plan B is something like an FD fuel pump"
1. Run a heavy gauge wire directly from the battery, 30 amp fuse in between, back to the fuel pump area. Cut the wire providing the stock "hot" to the pump and run it to the trigger side of the relay, the new "hot" to one side of the relay, other side to the wire running to the relay, and of course wire to the chassis to ground the other side of the relay trigger circuit. This will eliminate very common voltage drop the stock wiring will provide.
2. Agree, replace the stock fuel pump with one from an FD, or buy a Walbro or Denso aftermarket fuel pump. Very easy install process.
Goal for 1 & 2 is to help insure you don't lean out on your fuel. You lean out, pop does your engine. You might want to also invest in an EGT gauge or Wideband (narrow band that sources off the ECU is only good for entertainment value, not meaningful information) gauge so you can keep an eye on things so to avoid this dreaded leaning out.
Cat back by itself won't change boost, so I'm assuming you'll be installing a boost controller to up the boost. In the alternative, a RB downpipe and presilencer will get you to higher boost all by itself. Full REV II better still.
With all the above I'd still limit yourself to 7-8.5 lbs boost if you're running the stock ECU. But that should get you kissing 200 rwhp.
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^ same here. Eventually any engine will give it up. But I also got 200,000 miles on my old 87 TII before a water seal crapped out. You could have a couple years life yet to go on your block if you treat her nice.
#16
Quote from the RacingBeat inc. Rotary performance Technical Manual
"Cast iron (stock) apex seals are best for many applications. as long as you never exceed 8,500 RPM (RX-8 - 9500rpm) and dont run the engine highly supercharged (not exceeding 12 PSI of boost) the stock seals will "seal" better and last a long time."
"Cast iron (stock) apex seals are best for many applications. as long as you never exceed 8,500 RPM (RX-8 - 9500rpm) and dont run the engine highly supercharged (not exceeding 12 PSI of boost) the stock seals will "seal" better and last a long time."
#18
I would say that ANY kind of detonation is a issue. With any kind of turbo.
I'm pretty sure that racingbeats statment was not factoring in any detonation. since a properly tuned engine will not be detonating...
I trust what racing beat has to say.. after all they have been building these engines for over 35 years. They also have broken bonneville salt flats speed records, have won plenty IMSA championships and won there share of NHRA drag racing with rotarys...
I'm pretty sure that racingbeats statment was not factoring in any detonation. since a properly tuned engine will not be detonating...
I trust what racing beat has to say.. after all they have been building these engines for over 35 years. They also have broken bonneville salt flats speed records, have won plenty IMSA championships and won there share of NHRA drag racing with rotarys...
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