Car only has intake/hfc/exhaust. 2005 year. Installing EMS and was wondering what you guys set your redline to?
What can our motors rev to safely? Yes it is going to be professionally tuned.

 

There are several good threads about this. The maximum "safe" rev limit is going to depend a lot on how often you plan to hit it, and whether you'll ever "bounce" the rev limiter. Unless you intentionally tune for a very soft rev limiter (retard timing ~20 degrees for the last 100 RPMs), then bouncing the rev limiter can cause peak RPMs well beyond the rev limit. However, this may be more of an issue with the OEM ECU than it is with the AEM EMS. If the AEM can calculate engine RPM quicker than the OEM ECU, then it would be less of an issue.

That said, most people agree that 8500 RPMs on the AP2 is safe.

 

I could not find anything when I searched. Have any keywords to search for?
Wow 8500 redline? I dont plan on bouncing off the limiter but when your on the track, sometimes it happens so I'd rather be on the safer side.

 

http://www.google.com/search?q=raise...archBox&ie=&oe=

Keep in mind that the stock rev limit for an AP2 is 8200, so 8500 isn't really all that much higher. However, if you keep the gas pedal pinned to the floor even after the rev limiter kicks in, the engine will go 200+ RPMs beyond the rev limit, depending on which gear you're in. When I datalogged my AP2 in 3rd gear with the stock tune, it would exceed 8400 while bouncing the limiter.

 

The better question is, what do you hope to gain out of revving past 8200 rpm. Unless your engine has some more major mods you are exceeding your peak power band... power usually falls off before redline on our cars.

 

Power falls off but that longer redline keeps you in vtec for your next shift, where the power is

 

Optimal shift points are determined by how much torque is making it to the ground before and after the shift, not how much torque or power is being made at the flywheel. For example, if you are getting 135 ft-lbs of torque at 8500 RPMs, then that will equate to 2100 ft-lbs to the rear wheels in 1st gear (at about 39 MPH). However, when you shift to 2nd gear, your RPMs will drop to about 5500 RPMs where the engine makes about the same torque to the flywheel, but is greatly reduced to the wheels by gearing to less than 1400 ft-lbs to the rear wheels. The gap in torque decreases with each gear, but it never gets to the point that you would benefit from shifting earlier than the rev limit unless there's something wrong with the motor.

 

for what ?

That's the only real question, you know what adding rpms does to an engine - presumably you have handle on your finances and your ability to repair or replace the consequences of adding them.

I used to work for this idiot that thought spoon had laid down a challenge with there 11,000 rpm b16 - so we went about modifying a spare b16, spent tons of money and time into it and was able to exceed there limits and do so with an engine that could last at least 20 minutes that an average sprint race would go on for.

The problem is the engine was complete shit on the street and the reliability to cost ratio was horrendous and the power output to cost with other options were considerably better. I've known people to stuff nsx motors into the back of a del sol and produce a car no faster than a turbo b series swap for half the cost.

There really is no safe rpm limit, you might miss shift at red line and mechanically run the engine up to 14,000 rpm and then game over, can you afford to take those risks and why you would want to are yours to answer.

My answer is with your level of tuning and mods it's simply a bad idea to mess with it. You could and maybe see some gain but your going to pay for it in reliability over time, but it's your money.

 

Ive never fallen out of vtec when shifting on the stock ECU. If you're getting the car tuned its almost guaranteed that your vtec crossover point is being lowered which will keep you there anyways.

 

Ive never fallen out of vtec when shifting on the stock ECU. If you're getting the car tuned its almost guaranteed that your vtec crossover point is being lowered which will keep you there anyways.
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Ok you're abit confused, let's say I begin to build power at 5k in vtec with a redline of 8.2k. If i where to lengthen the redline to 8.5k, my next shift will put me higher than 5k making more power than I would at 5k. Gernby explained it a little better lol