I got bored again and decided to finally figure out what increase in HP can be expected at 8,500 rpm. Lets start with base power with the peak HP of 140 at 6800 rpm. Using the reverse of the torque to HP formula to find the torque at 6800(HP/RPM*5200). This gives us a 6800 rpm torque of 107lb/ft of torque. So if we tune the engine to keep this 107lb/ft of torque up to 8500 what gains do we get, for this we use the normal torque to HP formula(Torque*RPM/5200). The HP increases to ~175HP at 8500rpm, sounds good to me. Now lets say you are making 210HP N/T(at crank) and change the rpms, we'll assume you are making 210 at 7,000rpm. At 7,000 you are making 156lb/ft of torque. Raising the rpm's to 8500 with the same torque gives us 255HP. Another good increase.
The key word is tuning, I don't know exactly what is needed to tune for 8500rpm on these engines, but I think cams and cam gears, and some intake and exhaust work would be needed. How many out there are thinking about doing high rpm tuning?

except it's really hard to get a 2.0L 4banger to have that much torque that high in the RPMs.. i know mine.. and most others drop off pretty rapidly in the high rpms. either that or they have good torque numbers up high.. but down low they really suck and it makes the car hard as hell to launch and get good consitent runs.

But definatly, you can get it to hold that torque all the way up there without blowing up the valvetrain or anything.. that'd be sweet.

even with tuning you aren't going to get that out of a stock 420A motor. the car makes 140 crank hp at 6K rom from the factory, not 6800. plus hp starts to dive for the worse after that.....so does torque. even if you did tune the car for higher top end performance, you are still limited to the mechanics of your engine......which will probalby go south at about 8k. raising yoru rev limit doesn't necessarily mean an increase in power.......it meand tha tif you are making power all the way to redline......but if you aren't, then that is really about it.

A.D.P.
bring it on............

A.D.P.
"...If you do too much, people become dependant. If you do to little, people loose hope. If you do it right, people won't be sure you've done anything at all."
bring it on...........

Ohh, I mixed 4800 and 6000 together, this actually means we dont need to go as high as 8500, so at 7700rpm you would be making ~180 HP, if you couldn't go that high than lets try at 7200, our rev limit. That would give 168. Ohh, and I've said it before and I will say it again, f@#$ low-end, if you have to re-learn how to launch the car than do it, its worth the extra power. Also if you can run higher revs than you don't need to shift as much. Also would a quad TB setup help at higher rpms?

damn man.. ya starting to sound like a honda owner "come on! if I can just squeeze 9K RPM outta this thing i'll make some decent power!" hehe.. not trying to diss on ya, but that is the honda stratagy for making power.. the higher rpm the more power for them.

I think I want to hang out with some honda owners, the good ones of course. Look at F1, you think they could make the same power out of a 3L engine if they werent running 18-19000rpm, I don't think so. I'm just adding another N/T mod that gives good results