Revving above 7 g's
I am rebuilding another engine soon with all DH Racing parts and I just wanted to know how to remove the rev limiter and all the electrical side stuff. I know the results of over revving and I don't need to be schooled there, it's common sense, but when it comes to the ECU and all I do need a little schooling
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no. cant do that. Your car will either run like **** or wont run at all.
And if you did try to use an older ECU, you'll be spending way too much time and money than trying to reflash your current ECU.
And if you did try to use an older ECU, you'll be spending way too much time and money than trying to reflash your current ECU.
Autocross Junky
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There seems to be this thought floating around the import scene of If you can rev the engne higher that should give me more power/accleration. Unfortunatly its wrong. (Though it would be nice if it were true) See, power and acceleration is baised on the torque curve of a given engine, and as described its a curve. Meaning it has a peak and then drops. so a given engine, Folowing its torque curve, will make more power till its peak and then start to make less power, as the engine starts to make less power, there will be a point where the engine is making the same power as it would be at a lower RPM in the next highest gear. That is your optimum shift point. Where is that on our cars, well I dont have a Dyno to tell you. But I can say that its probably only a few hundred RPMs past peak HP (6300 on the EX, 6100 on all others).
So, Like I said before, the only reason you would need to change the redline on your civic is if you have Extensivly changed the torque curve of the engine. and even then you'd need to dyno your car to find the optimum shift points.
So, Like I said before, the only reason you would need to change the redline on your civic is if you have Extensivly changed the torque curve of the engine. and even then you'd need to dyno your car to find the optimum shift points.
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Rep Power: 607 Originally posted by Zzyzx
There seems to be this thought floating around the import scene of If you can rev the engne higher that should give me more power/accleration. Unfortunatly its wrong. (Though it would be nice if it were true) See, power and acceleration is baised on the torque curve of a given engine, and as described its a curve. Meaning it has a peak and then drops. so a given engine, Folowing its torque curve, will make more power till its peak and then start to make less power, as the engine starts to make less power, there will be a point where the engine is making the same power as it would be at a lower RPM in the next highest gear. That is your optimum shift point. Where is that on our cars, well I dont have a Dyno to tell you. But I can say that its probably only a few hundred RPMs past peak HP (6300 on the EX, 6100 on all others).
So, Like I said before, the only reason you would need to change the redline on your civic is if you have Extensivly changed the torque curve of the engine. and even then you'd need to dyno your car to find the optimum shift points.
There seems to be this thought floating around the import scene of If you can rev the engne higher that should give me more power/accleration. Unfortunatly its wrong. (Though it would be nice if it were true) See, power and acceleration is baised on the torque curve of a given engine, and as described its a curve. Meaning it has a peak and then drops. so a given engine, Folowing its torque curve, will make more power till its peak and then start to make less power, as the engine starts to make less power, there will be a point where the engine is making the same power as it would be at a lower RPM in the next highest gear. That is your optimum shift point. Where is that on our cars, well I dont have a Dyno to tell you. But I can say that its probably only a few hundred RPMs past peak HP (6300 on the EX, 6100 on all others).
So, Like I said before, the only reason you would need to change the redline on your civic is if you have Extensivly changed the torque curve of the engine. and even then you'd need to dyno your car to find the optimum shift points.
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Rep Power: 0 Since I have an HX, I typically will REV 1st all the way up too 7K, that way I start in the next gear higher up and closer to the power, cause If I shift at 6500, that'll drop me down to 3250 in 2nd gear, which is fairly low, so I typically rap it all the way out in 1st, so I can be as close to 400 as possible
Autocross Junky
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Rep Power: 380 ^^ true, Shift points are also influenced by gearing. wich is the problem you are runnin in to. Too tall of gears, great for gas milage, bad for acceleration.
I too would like to change my rev limiter to ...say ... 8000. That would be nice. The idea is to get a reground cam and to change the limiter to 8 so I would have a better top end with all my gears
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Rep Power: 374 The ECU is whats limiting you from reving high. No one make a program yet that raises the rev limiter on the D17 ECU. You would have to built your valve train to hold up anyways. Plus you would need to dyno tune the car to make any power above 7K. You could try to get ahold of Hondata and see if they will do a custom reflash for you. One of these days some one will make a new ECU for us. Also, you can not use a older ECU. Because of the immobilizor(SP?) We have on our ECUs. You might be able to get an older ECU you work if you by pass the immobilizor. But then I don't know if the fuel maps on an older ECU would be the same as ours.
Autocross Junky
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Rep Power: 380 Originally posted by hooter73mc
Now people are starting to see it my way lol. I want to rev that high so that when I shift into 2nd I don't drop out of Vtec.
Now people are starting to see it my way lol. I want to rev that high so that when I shift into 2nd I don't drop out of Vtec.
VTec isnt nearly as important as you seem to think it is, especially in our cars. Like I said you need to look at the torque curve and that will tell you when is the best time to shift, Vtec or not. 
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Rep Power: 359 Yeah, the vtec in our cars is mainly for fuel efficiency during high revs. Doesn't do much at all.
And going on what Zzyzx said earlier about the power. I can tell when I'm driving that after 6000 the car is done until I shift. It doesn't have much of anything after 6000.
You can almost feel that optimum shift point, it's that point where you can feel the car stop pulling you back into your chair. .
And going on what Zzyzx said earlier about the power. I can tell when I'm driving that after 6000 the car is done until I shift. It doesn't have much of anything after 6000.
You can almost feel that optimum shift point, it's that point where you can feel the car stop pulling you back into your chair. .
Originally posted by pheaton
Yeah, the vtec in our cars is mainly for fuel efficiency during high revs. Doesn't do much at all.
And going on what Zzyzx said earlier about the power. I can tell when I'm driving that after 6000 the car is done until I shift. It doesn't have much of anything after 6000.
You can almost feel that optimum shift point, it's that point where you can feel the car stop pulling you back into your chair. .
Yeah, the vtec in our cars is mainly for fuel efficiency during high revs. Doesn't do much at all.
And going on what Zzyzx said earlier about the power. I can tell when I'm driving that after 6000 the car is done until I shift. It doesn't have much of anything after 6000.
You can almost feel that optimum shift point, it's that point where you can feel the car stop pulling you back into your chair. .
Autocross Junky
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Rep Power: 380 ^^ yes, but how quickly does it drop off after that point?
as in whats your Torque and HP at 7,000 RPM and where else does the car make those #s? (in lower RPMs)
as in whats your Torque and HP at 7,000 RPM and where else does the car make those #s? (in lower RPMs)
