Hp estimation
05-23-07, 12:44 PM
#1
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Hp estimation
Since what I have is quite comon, I was wondering if you guys can tell me how much hp I can expect.
S4 TII stock is 186hp
RB exhaust states + 60 hp on the website.
K&N intake is 3% more
so just that would come close to 254hp.
Is that what I can expect?
S4 TII stock is 186hp
RB exhaust states + 60 hp on the website.
K&N intake is 3% more
so just that would come close to 254hp.
Is that what I can expect?
05-23-07, 02:23 PM
#6
They advertise that because that was the best result they got.
Its not false advertisement.................ebemlishment and false hope, yes.
Are 90% of the TII's running around going to gain 60whp from simply bolting on an exhaust? NO... 20hp? Perhaps
Are 10% of the TII's running around going to gain 60whp from dropping their 3 exisiting, clogged, 20 year old factory cats/pre-cats in favour of a better flowing new system? NO.............they WILL however gain more then the above scenario due to increased boost pressure/better exhaust flow. Not just ehxaust alone, but what the exhaust allows the engine to do
Lastly, get an FCD for the love of God. Exhaust and intake on a non-ported S4 wastegate is just asking for a boostspike and a blown engine.
My guess - 200whp +/- 10hp
Its not false advertisement.................ebemlishment and false hope, yes.
Are 90% of the TII's running around going to gain 60whp from simply bolting on an exhaust? NO... 20hp? Perhaps
Are 10% of the TII's running around going to gain 60whp from dropping their 3 exisiting, clogged, 20 year old factory cats/pre-cats in favour of a better flowing new system? NO.............they WILL however gain more then the above scenario due to increased boost pressure/better exhaust flow. Not just ehxaust alone, but what the exhaust allows the engine to do
Lastly, get an FCD for the love of God. Exhaust and intake on a non-ported S4 wastegate is just asking for a boostspike and a blown engine.
My guess - 200whp +/- 10hp
05-23-07, 02:31 PM
#7
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^just read your sig and LOL'd 
maybe it's CAPABLE of adding (up to) 60hp considering you having SUPPORTING MODS (ex. boost controller, FCD).
depending on what your engine had gone through (high miles perhaps?) could also plague the engine's expected performance...
IMO, a stock S4 turbo II with intake and exhaust would make around 200rwhp...
using the fuel injector calculator ( http://rx7.com/cgi-local/2ndgencalc.cgi ), you can see that using the STOCK 550cc injectors at it's max will only produce about 254 FLYWHEEL HP. so trying to go past that point with a stock set up can lead to VERY BAD things... just a heads up
maybe it's CAPABLE of adding (up to) 60hp considering you having SUPPORTING MODS (ex. boost controller, FCD).
depending on what your engine had gone through (high miles perhaps?) could also plague the engine's expected performance...
IMO, a stock S4 turbo II with intake and exhaust would make around 200rwhp...
using the fuel injector calculator ( http://rx7.com/cgi-local/2ndgencalc.cgi ), you can see that using the STOCK 550cc injectors at it's max will only produce about 254 FLYWHEEL HP. so trying to go past that point with a stock set up can lead to VERY BAD things... just a heads up
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05-23-07, 02:34 PM
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Whats an FCD?
I did not port my wastegate....is there some other way around this? Just the 2 gaskets cost 175$ together...
I have 720cc for secondaries though...
I did not port my wastegate....is there some other way around this? Just the 2 gaskets cost 175$ together...
I have 720cc for secondaries though...
05-23-07, 02:56 PM
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Fuel Cut Defender. It tricks your ecu into thinking you're always under the amount of boost that triggers fuel cut. The side effect is a lean condition.
Yes, add restrictions to your intake and/or exhaust. In other words, put the stock equipment back in.
awesome, what about your fuel pump? fuel controller?
You need to be very careful.
Not having an FCD might be what keeps the engine alive.. at least for a little while.
awesome, what about your fuel pump? fuel controller?
You need to be very careful.
Not having an FCD might be what keeps the engine alive.. at least for a little while.
05-23-07, 03:00 PM
#11
RB claims those gains because it will allow more boost due to better flow and less backpressure. It is a fairly reasonable estimate for at the wheel gains, though maybe slightly high.
What they don't say is that you will need to do substantial upgrades in order to support that added boost. Upgraded injectors, fuel controller, ported wastegate, etc. You should port the wastegate in order to prevent boost creep, which is totally seperate from anything a boost controller does. A boost controller can add boost, not turn it down.
Anyway, the numbers you are talking about are FWHP, which are pretty damn pointless for any car discussion. My guess would be in the neighborhood of 200 RWHP with your mods.
What they don't say is that you will need to do substantial upgrades in order to support that added boost. Upgraded injectors, fuel controller, ported wastegate, etc. You should port the wastegate in order to prevent boost creep, which is totally seperate from anything a boost controller does. A boost controller can add boost, not turn it down.
Anyway, the numbers you are talking about are FWHP, which are pretty damn pointless for any car discussion. My guess would be in the neighborhood of 200 RWHP with your mods.
05-23-07, 03:15 PM
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I forget what the exact pressure is that causes fuel cut but let's say that it's 7.8 psi. As soon as the boost pressure reaches anything over that, an FCD, when installed, fools the ecu into thinking that the boost pressure is only 7.8 psi. So if you're really boosting at 10 psi and the ecu is only adding fuel for 7.8 psi, that's a lean condition caused by the FCD. The injectors could very well be able to supply the ample amount of fuel, if only they knew the correct pressure. At least, this is the way I understood it when I had my TII. I'm sorry to everyone that read this if I'm incorrect.
05-23-07, 03:21 PM
#18
I dont see how they advertise 60hp gain and boost increase with no other mods. How will opening up the exhaust make the wastegate stay closed past the factory set boost setting? Ive never understood that. To answer the question Id say maybe look for a 25-30whp gain over stock
05-23-07, 03:28 PM
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I dont see how they advertise 60hp gain and boost increase with no other mods. How will opening up the exhaust make the wastegate stay closed past the factory set boost setting? Ive never understood that. To answer the question Id say maybe look for a 25-30whp gain over stock
Last edited by sonorous7; 05-23-07 at 03:33 PM.
05-23-07, 03:28 PM
#20
The wastegate is too small to begin with even with restrictive exhaust (barely). With no restriction in the exhaust, the engine can now breathe much better then before. Since it can breathe so well, it spews out MORE exhaust. The wastegate was too small before we added the extra flow, so now its overcome. More boost goes across the turbine fins instead of out the wastegate (because it can't fit all of it) and thusly produces more boost, then makes more ehxaust, which just snowballs the problem.
05-23-07, 03:42 PM
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It helps by adding the appropriate amount of fuel where it's needed. Search around for help on installing one. A popular choice is the Apexi s-afc II which goes for around $200 and piggy-backs onto your ecu.
05-23-07, 03:44 PM
#23
Fuel controller is a term more so then a specific product.
Products that fit the term would be:
S-AFC
HKS FCON
SDS Fuel Management
Greddy Emanage
AFC NEO
And all the standalones (Microtech, Haltech, Motec, PFC, etc)
Its simply a way of adjusting the amount of fuel you put in the engine. Ya know, managing your fuel.
Most would install at the ECU. Some would install at the injectors (kinda) And standalones let you pitch all that old cruddy trash in the garbage where it belongs.
Cost can range from $150 for used SAFC up to +$2000 for a full standalone.
Products that fit the term would be:
S-AFC
HKS FCON
SDS Fuel Management
Greddy Emanage
AFC NEO
And all the standalones (Microtech, Haltech, Motec, PFC, etc)
Its simply a way of adjusting the amount of fuel you put in the engine. Ya know, managing your fuel.
Most would install at the ECU. Some would install at the injectors (kinda) And standalones let you pitch all that old cruddy trash in the garbage where it belongs.
Cost can range from $150 for used SAFC up to +$2000 for a full standalone.
05-23-07, 04:04 PM
#24
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How does the SAFC connect to my ecu? I read the manual at http://www.apexi-usa.com/support_installation.asp but it doesn't say how to connect it.
And wont I need a wideband to adjust my air fuel ratio?
And wont I need a wideband to adjust my air fuel ratio?
05-23-07, 04:07 PM
#25
Ever hear of the reason behind why people port their wastegates? Obviously not.
The wastegate is too small to begin with even with restrictive exhaust (barely). With no restriction in the exhaust, the engine can now breathe much better then before. Since it can breathe so well, it spews out MORE exhaust. The wastegate was too small before we added the extra flow, so now its overcome. More boost goes across the turbine fins instead of out the wastegate (because it can't fit all of it) and thusly produces more boost, then makes more ehxaust, which just snowballs the problem.
The wastegate is too small to begin with even with restrictive exhaust (barely). With no restriction in the exhaust, the engine can now breathe much better then before. Since it can breathe so well, it spews out MORE exhaust. The wastegate was too small before we added the extra flow, so now its overcome. More boost goes across the turbine fins instead of out the wastegate (because it can't fit all of it) and thusly produces more boost, then makes more ehxaust, which just snowballs the problem.