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Let me start this thread with a disclaimer: I have never owned a boosted car. I do however have a strong mechanical understanding of the CDW-27 platform, helped with many engine swaps, rebuilt a CD4E, etc. I know how turbo chargers work, but I don't know about how the ECU must be adjusted to accept boost. This is the basis for my questions. My plans for the Cougar are as follows: First and foremost, this will be a track car, seeing 70% of it's time on the track ( Summit Point Raceway - 2 mile 10 turn road course). Therefore, my only conern is engine tune, durability, and power ... LOTS OF POWER! I plan to run at least 5 times a year during FATT (Friday At The Track) events and any possible "Seat Time" events held, funds permitting. By the end of the racing season next year, I would like to have my SCCA racing license and the following year, compete in the modified class. However, the other 30% of it's time will be spent running around the local area mountain roads (moving to West Virginia). I don't want to be forced to use 100+ octane race gas considering how expensive it is ... $5.50+/gallon. So, on to the questions at hand: Because I will need a "street" tune and a "race tune", I will obviously need a flip chip from ADC when I get the turbo kit. Since their solution is for one set boost level, how would the tune be affected by a boost controller? I'm figuring 8-12 psi of boost on 93 octane for the "street" tune vs 14-18 psi of boost on 100+ octane for "race" tune. So, I would definitely need the flip chip AND a boost controller to adjust the wastegate when I flip the chip. The chip controls the timing & fuel and the boost controller would allow me to up the boost for the setting in question and add more fuel, is this correct? At some point, shouldn't timing also be adjusted if the boost is increased more than a certain threshold?
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"Absolut Rara."
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"Absolut Rara."
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Boost controllers simply control boost by altering the signal to the wastegate for the turbocharger. All fuel and timing controls should be managed by the ECU.
IMHO, ideally you should have a two position chip, one position tuned for your "street" level of boost, and fuel, and you should have the other position tuned for the "race" level of boost and fuel. Then your boost controller should be set up to easily switch between the two boost levels, and make it tough to mix it up.
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Originally posted by Rara:
Boost controllers simply control boost by altering the signal to the wastegate for the turbocharger. All fuel and timing controls should be managed by the ECU.
IMHO, ideally you should have a two position chip, one position tuned for your "street" level of boost, and fuel, and you should have the other position tuned for the "race" level of boost and fuel. Then your boost controller should be set up to easily switch between the two boost levels, and make it tough to mix it up.
That is what I thought and had planned, but I find it odd that some people put these on their factory cars that come stock with 8 psi and overboost their engines to say 15 psi ... say for example, the VW 1.8T cars. That much more boost would definitely need to pull some timing no?
Last edited by fastcougar; 03/22/05 05:30 PM.
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"Absolut Rara."
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more than likely, yeah, they would need to change timing. But, on an engine that comes from the factory with forced induction, they usually have some method of compensating for more boost inside the ECU, though rarely is it ideal (because the factory never intended the increased boost) it can often keep an engine from turning into a pile of crumbly bits. The contour (or cougar) was never forced induction from Ford, so it never had any of the boost referenced controls in the ECU.
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Thanks Rara ... so there is no need for me to go all out and get the techno gadget controller like the Greddy Profec B or the APEXi AVC ... just a simple high/low controller.
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"Absolut Rara."
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not really, unless you want to set up rpm controlled boost curves and fancy stuff like that.
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Originally posted by Rara:
not really, unless you want to set up rpm controlled boost curves and fancy stuff like that.
Again, not being familiar with forced induction, I would assume that RPM boost curves would wook something like this:
2000-3000 RPM, run at 8psi
3000-4000 RPM, increase to 10psi
5000-6000 RPM, increase to 12psi
6000-7000 RPM, increase to 14psi
Is that a correct assumption?
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"Absolut Rara."
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not necessarily. Boost curves would depend on the turbo sizing compared to the engine, and to how the wastegate is controlled.
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Also depends on whether the pistons and rods are stock vs forged. Either way, rods can take more boost at lower rpms than they can take them at upper rpms. I'm not sure the exact formula, but stresses are not directly proportional at higher rpms. For instance the stresses on the rods at 6000rpms isn't twice as high as at 3000rpms, it's more like three times. That's why you don't see a lot of high rpm street cars aside from the Honda S2000 with it's 9000rpm redline. And even they recently put a bigger engine with a lower rpm because too many people were blowing engines because of oil starvation at high rpm/high side g's cornering.
So if you get the right kind of boost controller, you could set it to get 14psi from when it spools up, around 2500-3000rpms(depending on turbo/engine/etc..) to about 5000rpms then lower it to 8psi near the redline. While your peak HP may still only be as high as if you just ran 8psi, your TQ will be much higher and at the lowest rpm possible(and where you do the most driving).
I know the first turbo kit for the Focus used a aerocharger turbo that had built in boost controller that put out 12psi at 3000rpms and 240wtq, but by the redline lowered the boost to 9psi. It all depends on how you set it up, but I'd push the most boost down low you can run then lower it up high, especially if you're boosting a stock engine. And any mistakes and the engine is toast.
EDIT:
So your chart would look like this
2000-3000 RPM, run at 14psi
3000-4000 RPM, same
5000-6000 RPM, decrease to 10psi
6000-7000 RPM, decrease to 8psi
Most of your driving will be done under 4000rpms and will feel awesome on the street like that. Also on track, having a lot ot TQ down low could help pull you out of low speed corners easier.
Last edited by Seawulf; 03/25/05 06:48 PM.
2000 Rio Red I4 Cougar
200whp & 210wtq at 9psi
254whp & 276wtq with NX 35shot
WRX TD04 Turbo, Cut Short Shifter, Strut Tower Bar, 17" ZN Wheels, Roush Springs, Starion Intercooler, NX 35 shot, HKS SS BOV, Full 3" exhaust,StreetFlight Chip
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Originally posted by Seawulf:
Also depends on whether the pistons and rods are stock vs forged. Either way, rods can take more boost at lower rpms than they can take them at upper rpms. I'm not sure the exact formula, but stresses are not directly proportional at higher rpms. For instance the stresses on the rods at 6000rpms isn't twice as high as at 3000rpms, it's more like three times. That's why you don't see a lot of high rpm street cars aside from the Honda S2000 with it's 9000rpm redline. And even they recently put a bigger engine with a lower rpm because too many people were blowing engines because of oil starvation at high rpm/high side g's cornering.
So if you get the right kind of boost controller, you could set it to get 14psi from when it spools up, around 2500-3000rpms(depending on turbo/engine/etc..) to about 5000rpms then lower it to 8psi near the redline. While your peak HP may still only be as high as if you just ran 8psi, your TQ will be much higher and at the lowest rpm possible(and where you do the most driving).
I know the first turbo kit for the Focus used a aerocharger turbo that had built in boost controller that put out 12psi at 3000rpms and 240wtq, but by the redline lowered the boost to 9psi. It all depends on how you set it up, but I'd push the most boost down low you can run then lower it up high, especially if you're boosting a stock engine. And any mistakes and the engine is toast.
EDIT:
So your chart would look like this
2000-3000 RPM, run at 14psi
3000-4000 RPM, same
5000-6000 RPM, decrease to 10psi
6000-7000 RPM, decrease to 8psi
Most of your driving will be done under 4000rpms and will feel awesome on the street like that. Also on track, having a lot ot TQ down low could help pull you out of low speed corners easier.
He would be right, to keep power up top u would start putting timing into the equation. lower boost and advance timing.
for example on my wrx i ran alota timing down low to have power then as boost built up in mid range i lowered timing as rpm rose i started to drop the boost and increase timing again.
Experience is the worst teacher; it gives the test before presenting the lesson.
Why do you need the cats when u have dogs 
04 WRX - TOTALED 3-5-05
Previoius Owned: 96 Contour LX with svt kit
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