I have a 1992 Civic HB w/ an H22a. My whole interior is from an Integra GSR, which means the stock tach. Would my tach be accurate still? I know the redline is different from what the dash says, do you guys know where an H22 redlines at?

 

it should work just fine. and the redline on H22A is @ 7400RPM.

 

Yes the redline is at 7400 but you stop making power at 6900-7000.

 

So then whats the point of shifting at redline??? just shift at 7100...right??? yes, no...i dunno no more

 

no you still want to shift higher because say you shift at 7100 rpms then in the next gear you'll fall back to like 6200, if you were to have shift higher you would land in a higher rpm like 6400-6500(just an example). atleast thats how i see it.

 

no. you don't stop making power at 6900-7000. that may be the peak, the point of powerband where the motor makes most power (hp that is, tq peak is ussualy less than that). if it just stopped making power there then there would be no point of the 7400RPM redline. the right way to say it would be that it makes less than peak power after 6900-7000RPM, as you can see from dyno different dyno plots.
once the motor has reached that peak point, the power curve will start to drop slightly. this is common with almost every engine, although there are certain types that continue to make more power even above the redline.
at 7400RPM H22 makes plenty of power (though dynos show it drop) as it carries the momentum of that peak number from just 400-500RPM before.
it is important to shift right at redline in order to acheave that peak power sooner in next gear. and with VTEC engines this needs to be done in order to stay on high cam (VTEC). believe it or not, if you shift just a little too early it can make a big difference in your acceleration. thats why the redline is marked past that highest point. it is the whole power band that matters, it doesn't really matter that at redline your motor makes less hp than at 6900-7000RPM. it is actually better that way for overall acceleration. that's how your power band and your tranny work together.

 

BB1 yes all of that is true. Thanks for clearing that up.

 

 

and as you mod your car this point will change, i run a GSR program in my lude, and have found i get the best ETs when shifting at 8k..or like 7900...i also get better times witching into 4th..although i can hold it in third tillthe end at like 8200...and i dont feel any drop off at 7..like its just winding out, it pulls, you can tell more clearly how well it pulls past 7 by pushing it in 4th gear...the revs build slower and allow you a better feel...peace

 

sounds good to me. 13.7 is very impressive although you won't admit what mods you got that we don't know of. must be the typeR sticker yO!
but anyway, that sounds like very fine power-band and i can almost feel it...
now you should get an SMS header, straight 2.5inch pipe, and a muffler of your choice. should make a very strong bolt-on only car.

 

redline is at 7400 but the fuel cut is at 7625rpm as indicated by my VAFC. at the fuel cut , the tach was way into 8000rpm... so the stock tach is not really accurate at high rpms.