10 Grand Redline?


J_Spec_NiTeMaRe
05-01-2003, 10:50 PM
Hey I was reading a test done on an Integra GS-R... They added a high performance cam to it and gave it a dyno run. They found that it pulled super hard all the way to the redline, and hit the rev limiter. My point is, they said that they thought it was possible to extract another 10-15 horses by adding valve springs to let the engine rev higher.

I have a few questions about this.

1. Is it car specific, that adding valve springs to the Integra makes the redline higher? Or can you do that with a Civic or Prelude?

2. Are there any other things one could do to make your engine rev higher?

3. How do you figure out your actual redline when you do finally increase it? Do you have to remove the rev limiter?

4. Are there any benefits of raising the redline on a stock car, or should it be only used on modded engines?

5. And finally, when you do increase the redline, does it take longer for you engine to travel that wider powerband, or does it cover the longer distance, faster?

6. An unrelated question, I have also read about the Apex VTEC controller...Does anyone know how it works? I am led to believe that your engine has to be at a certain speed, AND have enough oil pressure to move the camshaft over to VTEC mode.... Does anyone know how much it is, and is it worth purchasing? Any first hand experiences?

civickiller
05-01-2003, 11:14 PM
lot of people think that just by putting on a cam they get more power at a higher rpm than stock. not really true, u wanna make more power, get the engine more air, i e intake, tb, intake mani, p&p. the more air u get the engine the high the top end torque is. see the goal is to increase the torque at a higher rpm, instead of having it drop off like it normally does.

the upgrade fo the valve springs is so that when u do rev higher than stock, u dont break a valve spring, just adding the valve springs doesnt mean you got a high redline, but it does mean your valvtrain can handle higher than stock revs

as far as i know the only way to figure out a the peak power is to dyno it. u rev higher than stock, u have to either completely remove the rev limiter or just make it higher.

from what i read, theres no point in going higher than stock, on a stock engine, yeah it takes alittle extra time but not much

umm thats all i can answer, plz something respond if they think im wrong

91civicDXdude
05-02-2003, 12:11 PM
6. An unrelated question, I have also read about the Apex VTEC controller...Does anyone know how it works? I am led to believe that your engine has to be at a certain speed, AND have enough oil pressure to move the camshaft over to VTEC mode.... Does anyone know how much it is, and is it worth purchasing? Any first hand experiences?


VTEC controllers work by intercepting the VTEC signal from the ECU and adding its own signal. With a stock ECU, you have to have a certain engine speed, car speed, oil pressure, and temperature for VTEC to activate, but this is just a safety precaution. if you were to hook up a direct toggle switch to your vtec selenoid, it will tell the selenoid to activate VTEC whenever you toggle it to do so, as long as you have the proper oil pressure to ACTUALLY activate VTEC.

With a stock or very midly modified engine, a VTEC controller is nothing more than a shiny toy. But if you are like me and are using a non VTEC ECU with a VTEC engine, then a VTEC controller is a must to program in the fuel mapping and VTEC activation point.

On a heavily modified engine, a VTEC controller is an important tuning tool, especially with aftermarket cam(s).

94tegRS
05-02-2003, 09:33 PM
could I use my integra LS ECU and just get a VAFC when I go crvtec?

always thought i was gonna have to get a GSR ECU to have vtec kick in.

911GT2
05-03-2003, 01:41 AM
Higher lift/duration/overlap cams will get you more power up high, but it'll be utterly unuseable on an engine like the B18C.

Think people, how often do you put YOUR engine up to 9K??

PWMAN
05-04-2003, 07:59 PM
Originally posted by 911GT2

Think people, how often do you put YOUR engine up to 9K??

If I had a B18C I would scream it- which is like 8600 fuel cutoff I think. But I only have a B18B and cutoff is at 7200, so I only take it to 7K RPM, but I do so on a regular bases.

94tegRS
05-04-2003, 09:09 PM
yeah, me too, I took mine up to 7k every day, many many times.

liquid8
05-05-2003, 06:01 PM
i believe the gsr rev limit is at 8200. i'm pretty sure but i could be wrong

redmanjd
05-05-2003, 06:08 PM
if you rev you engine to high and to much your cams will start floating.that is when your cams are rotating too fast and the valve springs cant catch up. yes you can get dual valve springs but if you dont get new cams the springs will wipe the lobes off your can. and you also need to get your engine balanced so it doesnt fly apart and you need a block gridle. so high rpms = valves, cames, balanced, gridle

J_Spec_NiTeMaRe
05-05-2003, 09:16 PM
Alright thanks everyone. What is a block gridle though? And why would I need this on a Prelude(the import that I will probably end up getting)?

civickiller
05-06-2003, 03:26 AM
i thought it was 7800 because the b16 is 8200 which is suppose to be able to rev higher than the gsr.

block girdle, block guard ? if hes talking about a block gaurd, i would say get one if your going turbo or all motor or nos, but if its just a stock motor, u wont need one. it depends on what u doin to the motor, what the plans are

whtteg
05-06-2003, 10:25 PM
Originally posted by J_Spec_NiTeMaRe
Alright thanks everyone. What is a block gridle though? And why would I need this on a Prelude(the import that I will probably end up getting)?

The girdle bolts to the three center main caps on the crankshaft. It helps reinforce the rotating assembly at higher rpms, All b18c motors have them from the factory and you can put one on a b18b1 if you have the main caps, windage tray,oil pick up and pain, and ofcourse the girdle hehe:p I have all of these which came out of a b18c5 and I am going to build my b18b1 to give me 8200 rpm b/c I have a set of crower 62404 cams which are supose to produce good power and torque to 8200 rpms.:D

mellowboy
05-07-2003, 11:33 AM
Yeh if you wanna rev high u gotta build your bottom end. Get it balanced and everything. Theres a guy near my town runs 11 grand. Sure u can take it up that high ( when its built ) but that doesn't mean all the power is there:)

Frostbyte
05-07-2003, 05:10 PM
Originally posted by J_Spec_NiTeMaRe
Hey I was reading a test done on an Integra GS-R... They added a high performance cam to it and gave it a dyno run. They found that it pulled super hard all the way to the redline, and hit the rev limiter. My point is, they said that they thought it was possible to extract another 10-15 horses by adding valve springs to let the engine rev higher.

I have a few questions about this.

1. Is it car specific, that adding valve springs to the Integra makes the redline higher? Or can you do that with a Civic or Prelude?

2. Are there any other things one could do to make your engine rev higher?

3. How do you figure out your actual redline when you do finally increase it? Do you have to remove the rev limiter?

4. Are there any benefits of raising the redline on a stock car, or should it be only used on modded engines?

5. And finally, when you do increase the redline, does it take longer for you engine to travel that wider powerband, or does it cover the longer distance, faster?

6. An unrelated question, I have also read about the Apex VTEC controller...Does anyone know how it works? I am led to believe that your engine has to be at a certain speed, AND have enough oil pressure to move the camshaft over to VTEC mode.... Does anyone know how much it is, and is it worth purchasing? Any first hand experiences?

If you want to raise the Rev Limit on a Civic a thing to remember is the civic D series VTEC engine can handle a 9k redline without changing the Valve Train Componants.

flylwsi
05-07-2003, 06:20 PM
they thought it was possible to extract another 10-15 horses by adding valve springs to let the engine rev higher

stronger valve springs decrease valve float, which is bad, b/c they tend to slam into pistons at that point.

you can't make power at any higher rpm than the stock cam unless you change out the cam.

my car's cams run out of room at 6500 or so. i could rev higher, but the power has already peaked and is dropping.

you need to upgrade the cams to rev higher.

if you rev higher, you need to upgrade the springs, like i said.

you also need to consider the bottom end, b/c you're moving those commponents much faster than previously possible...

If you want to raise the Rev Limit on a Civic a thing to remember is the civic D series VTEC engine can handle a 9k redline without changing the Valve Train Componants.

to put it lightly, i'm going to at least question that statement...

if you rev you engine to high and to much your cams will start floating
as noted, cams don't float. they are firmly held in place.
valves float.

Frostbyte
05-12-2003, 07:56 PM
Originally posted by flylwsi

to put it lightly, i'm going to at least question that statement...

It actually has been proven many times over that the D series VTEC engines have a strong enough valve train to handle a higher redline. Infact if you get the Gude head package they tell you not to replace the valve train and to leave it stock.

Marasmus
05-13-2003, 02:15 PM
Raising the redline can certainly be done on any engine. Whether it will give you any positive results (or blow your engine) is entirely another story. Sometimes more is NOT better!

What actually makes your car move is torque. By widening your RPM range, you can get more effective torque to the ground because you can drice in each gear over a wider range. Alternatively, building your engine to produce more torque at the same RPM is the other way of getting more effective torque to the ground (stroking, boring, forced induction, nitrous). :)

Combustion engines and their components are all designed to run within a strict RPM range. Honda's engines (like most companies') are put together from the factory with components designed to handle a bit more than stock power, but using as little overkill as possible to create the most efficient and cost-effective machine. When you start working to raise the redline (and useful powerband), you will find that the requirements needed for MANY components to run in that range must be changed. Honda's bottom-end balancing on B-series motors is excellent, but the rods, pistons and bearings can be improved upon to gain added stability and reliability at high RPM.

Likewise, the valvetrains of VTEC engines can often go to 8600rpm without modification, but above that range, valve float and valve misalignment WILL occur and WILL destroy your engine unless you rebuild your head and valvetrain components to higher specifications. Lighter, stronger valve springs, valves and retainers are all needed. Some people even replace the rockers. Lubrication needs may require you to change the oiling system a little bit.

Air and fuel input must also be increased. Kick up a stronger fuel pump, bigger fuel rail and injectors, and a better fuel pressure regulator to ensure that you can get the fuel to the cylinder at those high RPMs. Your air intake will need an ugprading, along with your throttle body. You can either replace or port your intake manifold and head to accomodate more air and better air flow, depending on your application. Then, design your exhaust to meet the increased flow requirements with the least sacrifice of low-rpm efficiency.

Then come the ancillary things you wouldn't think about at first: clutch, LSD, certain sensors, ECU (reprogramming), underdrive pulleys (chances are your power steering pump isn't designed for 10krpm operation, nor your alternator!)... By the time you're done mapping everything out you'll realize that it'd cost you a solid $10,000 or more to really do it right. It's an expensive ordeal, and won't give you much (if any) more power than a good turbo or supercharger setup at half the price.

At the very least, you'll gain a serious respect for Honda's engineers, creating the fine-tuned balance of all the operating parts in that engine!

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