redline shifting fact or fiction?

[Juice21]

ok i ve been talking to some new ppl lately that i am hanging with, and ive been getting some new info that seems far fetchd.

so now they are telling me that i should be shifting between 7.6k and 8k rpm.
and there telling me with there b16s, b18s, and b17s, with basic ihe, they are shifting at 9k rpm. my thing is that the h22 redlines at 7.2k i think. isnt the area beyond that red for a reason? i dont like taking risk because i dont have the money to pay for any problem i may cause to the engine but they are arguing with me telling me that the h22 can handle higher rpm shifts.

so can someone plz hit me with the facts. it is very much appreciated

[visualpoet]

Factory redline is there because the engine isn't tuned to rev much past that. When you start modifying an engine, you can move the point of safety (redline). In order for your engine to redline higher, you need to have adequate fuel/air delivery and removal to keep things safe, plus, (as you get it even further above factory) things will need to be balanced and well maintained. Unless you've really built your motor, I wouldn't listen to these people. It sounds like they want you to cook the block.

At least that's the way it was explained to me years ago.

[Juice21]

Factory redline is there because the engine isn't tuned to rev much past that. When you start modifying an engine, you can move the point of safety (redline). In order for your engine to redline higher, you need to have adequate fuel/air delivery and removal to keep things safe, plus, (as you get it even further above factory) things will need to be balanced and well maintained. Unless you've really built your motor, I wouldn't listen to these people. It sounds like they want you to cook the block.

At least that's the way it was explained to me years ago.

when u say built motor u mean engine internals ryt not just bolt ons? my ecu was tuned but nvr asked where is ok to shift at, supposed to get it etuned soon

[501accord]

i dont have the money to pay for any problem i may cause to the engine

then don't beat on the car... duh.

[CBAccordA4]

thats average for a tuned h22 shifting between 7500 and 8000. Stock h22 wouldnt make much sense revving up to 8000 but it will make more significant power up there when tuned. Now I wouldnt rev past 8 on a stock valve train.

[92turboaccord]

i thought there wasnt any power gains over 7200 if its stock... and a b16 is a high strung motor

[d112crzy]

Unless you took your car to a tuner, he sat in your passenger seat with a laptop and tuning tools, you are not tuned.

Your rev limit is determined by your power band. I've tuned stock block/head h22's that pull past 8k without a problem. That's pushing the limits of the valve train tho.

[CBAccordA4]

i thought there wasnt any power gains over 7200 if its stock... and a b16 is a high strung motor

Well over 7200 rpm might not be where the peak power is, but to achieve optimum acceleration you want the motor to be winding as fast and as safe as possible while making significant enough power. Therefore if your peak power is about 200 @ 6800 rpm and your making only 140- lower @ and under 7200 rpm, I probably would be revving in that range but if I was making 180hp @ 7200 then you have likely cause to be revving and shiftingup and around and even past that point assuming your engine can handle the revolutions.

Unless you took your car to a tuner, he sat in your passenger seat with a laptop and tuning tools, you are not tuned.
Your rev limit is determined by your power band. I've tuned stock block/head h22's that pull past 8k without a problem. That's pushing the limits of the valve train tho.

If you were referring to what I replied (not sure) well the h22 I was mentioned was tuned using hondata s300 by RPM in queens. I think everyone knows what "Tune" means. Anyway I was checking out your member shop, wish you were closer because your prices are pretty decent. You know anyone with a f22b stock motor that you can tune on??

[Shadow1]

if your not tuned then theres no point shifting at redline. your not making power that far so theres no point to shift there.

just like with the F22a. they dont make any power past like 52-5500 RPMs. so shift at red line where my power is gone?

[Juice21]

then don't beat on the car... duh.

how does this answer the question of if a h22 can shift between 7.5k and 8k im asking if its safe to shift there,

if u dont have the answer to help in this thread then plz dont post

[blackice]

redline is technically 7600 on the stock ecu with fuel cut at 7800.

[Flatline]

why'd everyone stop? this is really on my need to know list. personally i never shift within a couple hundred of redline just to be safe.


but i have seen vids of h22 Cb's revving up to 8k with ease.....

kit-2-lip had an H that broke a retainer and dropped a valve.... i'm not sure but i would say it's because of revving the motor into there too much...

[Fake Thug]

if your not tuned then theres no point shifting at redline. your not making power that far so theres no point to shift there.

just like with the F22a. they dont make any power past like 52-5500 RPMs. so shift at red line where my power is gone?

You ARE making power at redline its just peaked as in stationary/plateaud. Thats why there is no point in revving past 5800 on a f22. The wasted energy which amounts to wasted time can be better applied hitting the peak for a second then shifting.

[4GAccordH22]

If you were tuned on a dyno, you should have a dyno sheet. Look at your peak HP and where it is (probably right around 7K) and shift 200-400 RPM higher than that. There's no point in going much further than that as the higher you go, the more risk of damaging the motor.

Also, one thing that could increase your redline is your valvetrain. The valves have the possibility of floating about 8K on the H22, and that is bad. Stiffer valve springs and cams that can make power above 8K would effectively raise your redline beyond 8K

[batever]

then don't beat on the car... duh.

how does this answer the question of if a h22 can shift between 7.5k and 8k im asking if its safe to shift there,

if u dont have the answer to help in this thread then plz dont post

While I agree that the "duh" part of his comment was not respectful,
I disagree that his comment overall was unhelpful/ not a contribution to your question.

While he didn't directly address the theoretical safety of shifting between 7.5 and 8K, I think he was just pointing out that, if you REALLY can't afford to pay for engine work/damage, it's better to avoid high rpms in the first place. Even if the engine is designed to redline at 7000 or 8000 rpms, if you rely on the car for transportation and have no cash to pay for engine work, it's much more prudent to put off your need for speed and just keep the rpms below 3200 than it is to even go to 5000 or 7000.

Now, it sounds like you want to be able to shift high but do it within relatively safe parameters, that's your choice, still it's not as safe moneywise as keeping the RPMS in the lower range is.

The valve float issue would be the one that would cause you the real financial hardship if you run into it, that's what I would set my shifting limits at and that's what the redline is conservatively set at I believe--it's a warning that the valve train can't keep up with the pistons above that speed.

Also, depending on the age of the valve train, the springs can weaken over time, increasing the amount of time they take to return the valve to a closed position--all springs weaken over repeated cycling and repeated heating/cooling, so the redline for a new engine might not represent the conservative redline for an older engine/older valve springs. I'm not sure how much they weaken or if it's significant, someone else will have to chime in on that.