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Discussion Starter #1
cobb stage 2 =285 hp & 340tq. 18g with cobb map = 365 hp & 322 tq. My question is how can stage 2 make more tq than the 18g ? With 80 less hp .Could someone explain the technical stuff to me in a way that I'll understand ? thanks in advance
 

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First what kind of cars are these? 2.5L or 2.0L? STi, WRX?
 

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thats just a genaric map for that turbo that will work for every car, if you were to get a protune with that turbo and supporting mods you would be well above those numbers
 

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Discussion Starter #6
thats just a genaric map for that turbo that will work for every car, if you were to get a protune with that turbo and supporting mods you would be well above those numbers
Yeah, I understand that. What I don't understand is with approx 80 more hp how could the tq go down by almost 20 ?
 

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Discussion Starter #7
C,mon guys I know there are some of you that know. Or is it some kind of secret that none of us noobs can know:)
 

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You know what a force is - when you push on something you are applying a force. Torque is a force applied to a lever arm; the combustion process allows a piston to apply a force to the crankshaft, turning linear motion into rotational motion. Your engine makes torque.

Power is how fast that torque can be continuously applied. Horsepower is torque*rpm/5250 (you will notice that the torque and horsepower curves always cross at 5250 rpm). The stage 2 setup has higher torque at lower rpm - great for daily driving - but the torque falls off at higher rpm as the turbo runs out of steam. The 18g requires more exhaust energy to get it spinning so the torque peak arrives later, but it doesn't run out of breath at the higher rpms so the torque plateau extends farther up the rpm range. I am surprised to see that the OTS map would show less torque on the 18g map, but as stated above a protune would quickly remedy that.

Remember it this way - a 4 cyclinder Chevy Cavalier and a two-rotor RX7 both make about 100 ft-lb of torque over a very broad range, but the chevy motor redlines at 6K and the RX7 at 8K. The RX makes a lot more horsepower.
 

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but the chevy motor redlines at 6K and the RX7 at 8K. The RX makes a lot more horsepower.
The RX-7 tach only stops at 8500 but any true lover of the RX-7's know that they will run much further then that :D lets just say they will rev until they melt.
 

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Amen! I had a Killer B in my 85 RX7 - Mazdatrix told me to be conservative when I ran it. 'Try not to go over 10,000 rpm...' :)
 

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Does anybody know ?

tshrey pretty much summed it up but basically puny turbo on a 2.5 vs a bigger turbo on a 2.5. Thats why, and like he said, those 340 torque come in early and die early, 18g torque is a much better curve at higher rpm's. But low end torque stage 2 would be a fun daily driver.
 

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Discussion Starter #13
tshrey pretty much summed it up but basically puny turbo on a 2.5 vs a bigger turbo on a 2.5. Thats why, and like he said, those 340 torque come in early and die early, 18g torque is a much better curve at higher rpm's. But low end torque stage 2 would be a fun daily driver.
It is a fun daily driver . But from what I've heard ,that much torque can break my tranny. So would the 18g set up be less likely to break my tranny even though it has more hp ? Right now I am at cobb stage 2 and the tq # are 340 . The 18g has 322 #tq .These are not dyno #s ,just the #s that are on cobbs website.
 

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18g has a higher chance of busting a tranny, you have more power and higher torque for a longer amount of time. Plus that 340 torque isn't wtrq.
 

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Discussion Starter #15
18g has a higher chance of busting a tranny, you have more power and higher torque for a longer amount of time. Plus that 340 torque isn't wtrq.
So ppg gears or sti swap before an 18g setup ?
 

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If you can save money for a tranny swap and do the turbo swap i'd do it and drive it till i bust it but thats just me. If your gonna have trouble saving money for a tranny swap after your upgrade, i'd hold off on it. Based on your other thread, i'd hold off on it.
 

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So ppg gears or sti swap before an 18g setup ?
I was using my 20g with protune (conservative) for 20k miles before i swapped in my 6speed. I also have an 06 and made sure therewas no harsh launching, smooth upshifts and rev matching downshifts. It might not be the same for other 06 stage 2 users, buti can confidently contribute i was running waaaay more power than stock on my original 5 speed. It was running well up until the day I took it out. The swap was preemptive and I had a buyer for my stock tranny.

Drivetrain upgrade isn't necessary but keep in theback of your head
 

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Discussion Starter #20
If you can save money for a tranny swap and do the turbo swap i'd do it and drive it till i bust it but thats just me. If your gonna have trouble saving money for a tranny swap after your upgrade, i'd hold off on it. Based on your other thread, i'd hold off on it.
Oh I'm definately going to hold off on it . I don't have any choice,or money. I just can't stop thinking about doing stuff to the rex. I drive my wife crazy when I talk to her about it. She thinks I'm obssesed :screwy:
 
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