makes boost so fast... is that normal?
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makes boost so fast... is that normal?
87 tii with 3"dp and cone filter and stock WG and stock catback.
under WOT in first gear it makes 4-5lbs by 3kRPM and hits fuel cut at 5k rpms or so.
is that normal? i just got the car and people keep telling me that is making boost faster than normal. Could the turbo be upgraded? would that make it go slower or faster?
I keep hitting fuel cut even with my FCD! its a hks FCD and no one knows what to set it to.
under WOT in first gear it makes 4-5lbs by 3kRPM and hits fuel cut at 5k rpms or so.
is that normal? i just got the car and people keep telling me that is making boost faster than normal. Could the turbo be upgraded? would that make it go slower or faster?
I keep hitting fuel cut even with my FCD! its a hks FCD and no one knows what to set it to.
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Well first thing is first. YOU DONT WANT TO BE HITTING FUEL CUT. I mean thats the point the engine goes caa-boom. Get that thing tuned right. You should be gradually continuing to boost not hitting fuel cut, thats really dangerous. As far as boost, one of the main reasons its creating boost so fast is 1. a 3" dp and 2. you have a stock wastegate. Once you get that FCD tuned you should boost to 12 or 14 psi or so but you need to get that under controll very quickly.
Turbo's must be modded in sequence so that you dont risk blowing up your engine.
Turbo's must be modded in sequence so that you dont risk blowing up your engine.
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i have a s4 turbo on the way with "grosely" ported WG as he put it and ported exhaust runners. im going to send mine in to get upgraded.
so no one knows what setting to put this thing on? the hks fcd that is.
so no one knows what setting to put this thing on? the hks fcd that is.
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Originally posted by RylAssassin
Well first thing is first. YOU DONT WANT TO BE HITTING FUEL CUT. I mean thats the point the engine goes caa-boom. Get that thing tuned right. You should be gradually continuing to boost not hitting fuel cut, thats really dangerous. As far as boost, one of the main reasons its creating boost so fast is 1. a 3" dp and 2. you have a stock wastegate. Once you get that FCD tuned you should boost to 12 or 14 psi or so but you need to get that under controll very quickly.
Turbo's must be modded in sequence so that you dont risk blowing up your engine.
Well first thing is first. YOU DONT WANT TO BE HITTING FUEL CUT. I mean thats the point the engine goes caa-boom. Get that thing tuned right. You should be gradually continuing to boost not hitting fuel cut, thats really dangerous. As far as boost, one of the main reasons its creating boost so fast is 1. a 3" dp and 2. you have a stock wastegate. Once you get that FCD tuned you should boost to 12 or 14 psi or so but you need to get that under controll very quickly.
Turbo's must be modded in sequence so that you dont risk blowing up your engine.
#5
Originally posted by Matlock
When does fuel cut go kaboom? It's not much different then ignition cut. I use it as my rev limiter and have hit it multiple times.
When does fuel cut go kaboom? It's not much different then ignition cut. I use it as my rev limiter and have hit it multiple times.
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When does fuel cut go kaboom? It's not much different then ignition cut. I use it as my rev limiter and have hit it multiple times.
An ignition cut wouldent be as bad as a fuel cut, in my opinion. But why cut anything at all is my point.
As far as tunning that HKS, i have no clue i dident even know they made a FCD...
Last edited by RylAssassin; 09-01-03 at 09:02 PM.
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Originally posted by Matlock
Explain please???
Explain please???
don't quote me on either, but I just know fuel cut has killed a few engines.
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But there is no fuel. Fuel is what goes kaboom. So your lean actually your only running air. Dunno, I'm not worried. THe reason to cut something is 1st, 2nd gear, lightweight flywheel, and T4=9k before you can think about shifting.
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there is still fuel in the intake runners for a rotation or two after it cuts. That means it's extremely lean for a second.
And I don't know about the RX-7 turbo, but my MR2's turbo will produce 13-14 psi in just first gear.
And I don't know about the RX-7 turbo, but my MR2's turbo will produce 13-14 psi in just first gear.
Last edited by rotary>piston; 09-01-03 at 09:20 PM.
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Goog thing I am extremely rich. Back to the question your turbo will spool quit fast with those mods. Sounds right to me. I am a moron when it comes to these wacky rotary engines though!
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But there is no fuel. Fuel is what goes kaboom. So your lean actually your only running air. Dunno, I'm not worried. THe reason to cut something is 1st, 2nd gear, lightweight flywheel, and T4=9k before you can think about shifting.
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fuel cut
When fuel is cut to one of the rotors you will run lean and risk an incredible chance of blowing your engine. If you don't have an FCD then you should not be breaching 8 or 9 psi otherwise you will risk destroying your engine.
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yea thats why im asking for help tuning this thing.... i dont want anymore runs to "test" it.
im waiting to hear back from the guy on here that makes them... so i guess ill take it easy till then.
im waiting to hear back from the guy on here that makes them... so i guess ill take it easy till then.
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Re: fuel cut
Originally posted by PureSephiroth
When fuel is cut to one of the rotors you will run lean and risk an incredible chance of blowing your engine.
When fuel is cut to one of the rotors you will run lean and risk an incredible chance of blowing your engine.
Based on people's shared experiences with FC's, there does seem to be some risk of engine damage when repeatedly and frequently hitting fuel cut, but this is not due to lean condition.
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Originally posted by Matlock
But there is no fuel. Fuel is what goes kaboom. So your lean actually your only running air. Dunno, I'm not worried. THe reason to cut something is 1st, 2nd gear, lightweight flywheel, and T4=9k before you can think about shifting.
But there is no fuel. Fuel is what goes kaboom. So your lean actually your only running air. Dunno, I'm not worried. THe reason to cut something is 1st, 2nd gear, lightweight flywheel, and T4=9k before you can think about shifting.
Do you honestly believe my being stronger or faster has anything to do with how strong or fast I am in this place? Do you think that's air you're breathing? hm...
ANYHOW.. there's going to be some fuel left over somewhere in the system when it cuts fuel at full throttle.. that's why it can run lean.
#17
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Originally posted by Barwick
You think there's no puddling of fuel in the intake runners when you're running under boost? Hmmm?
ANYHOW.. there's going to be some fuel left over somewhere in the system when it cuts fuel at full throttle.. that's why it can run lean.
You think there's no puddling of fuel in the intake runners when you're running under boost? Hmmm?
ANYHOW.. there's going to be some fuel left over somewhere in the system when it cuts fuel at full throttle.. that's why it can run lean.
Is everyone forgetting that the injectors do not flow all the time? Their pulse corresponds to eccentric shaft rotation, and thus to airflow. The injectors are not on all the time.
The injector pulse is cut, so their is no flow of fuel for that specific combustion chamber. There is no fuel, and thus no combustion.
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