First of all, it is all in your ECU, your TACH has nothing to do with it, you can drive the car around with no gauge cluster at all, and the car will still hit VTEC. IT gets the signal from the ECU.

 

Thanks for setting me straight on that. So, in other words, it sounds like the tach is just screwed up. I just need to get something hooked up to verify.

 

That's not quite right. VTEC uses a signal from the VSS which is located in the cluster to decided whether to engage VTEC or not. But yes, it doesn't use the actual tach.

I use my OEM tach and it works fine right up to 8200.

 

i would say your tach is fine....sure you went up to lets say 10,000 rpms. no...your tach doesnt max at 8,000....sure...the writing on the tach says eight...but in reality you can go all the way back to zero (because there is a bump stop do-dad there). like i stated earklier....STOP RELYING ON YOUR TACH!!!!!!!!!! pay attention and listen to what the car is doing and feeling...stop worrying about your gauges...they are there for reference only and really have no meaning once you find out in the beginning of tuning the car.......

for example....your gas gauge....you only need it in the beginning of buying or driving the vehicle. do you satre at the gas gauge??? no....you glance at it. from then you can realize how long you can travel or whatnot. from that beginning glance you can actually trip the odo and then never have to worry about your gas gauge again...just fill it up at 200 miles.

another example...boost gauage......you only need it in the beginning of the tuning process.....from then on out...you are not staring at your boost gauge. only there for reference. trust me....if the wastegate fails....you will feel a surge of power or vice versa.

now the final example...the tach....once you get good enough...you can hear where the car is at rpm wise. i dont even look at my tach anymore when i am racing...

so to close things up here....pay attention to what the car is doing??? does it sound like it is at 5,000 at 70? or does it sound like it is at 4,000 at 70. sure...put a new tach in it...but you are just wasting money....it is in wiring not the gauge itself.

 

Ok, ok, enough about the tach. I've been driving a manual trans for 24 years and actually a CRX for the last 15. I'm very familiar with the sound and don't need the tach to shift. Even though the b16 in this one revs higher and sounds louder (ractive exhaust) I still say something is wrong. The v-tech kicks in on a slow acceleration at around 80mph. That's a fairly common highway speed around here and I never had it kick in that early before. It didn't usually engage until 90-95mph. No, I don't drive that fast. But yes, like everyone else, I had to see what it could do.

Hell, maybe the speedo is screwed up. When it shows 70, maybe I'm really doing 80 and when the v-tech engages at 80, maybe I'm really doing 90. I dunno. I guess I can have someone drive another car by me to test the speedo.

 

dude...this thread is so stupid. you have no idea what you own nor drive. if you have driven a honda for 15 years you should know how to spell vtec. its not a phone moron. a b16 tranny has really close gearing. vtec activates regardless of flooring the car. if you drive slowly...(which you stated above) wherever your vtec point is.....it will switch to high cams. (vtec mode since you probaly dont know what vtec does). the i-vtec in later hondas changes the cam lobes while the throttle body is completly open...or floored if you will. this thread is stupid and you should be shot.

 

The thread is only stupid for the person that can't post a descent response. Let me clear some things up for you. The Honda CRX that I drove for 15 years didn't have a vtec. It had a D15 with a manual trans. In 15 years, the only thing I had to do was change the fluids, brakes, exhaust, battery, and an alternator. I don't think I even had to replace a light bulb in 15 years. What I'm trying to say is that it was basically a trouble free car. I knew how it rode, sounded, and handled.

The CRX I recently bought had the JDM b16 swap already done, and yes, I know little to nothing about the vtec motor. About all I know is that when the engine reaches a certain RPM, a mechanical sliding pin locks the other "high RPM" cam in place for more power in the upper range of the motor.

This thread was started so I could pick the brains of the so-called experts on why my RPM/speed ratio changed suddenly. So far this is what you've had to offer:

"omg...and your a senior member? is this your first b16 swap? yeah i thought so."

"your flywheel makes no diffrence at alll........if you dont like it...get a ls trasnny" (and you're ripping me on my spelling of vtec?)

"unless the needle is jumping around....you dont have a problem. did you just put the rims on?

"the only thing i can say....is pay more attention. you should be able to "hear" the cars rpms by now."

OK, I'm done bitchn'. Just a little frustrated at being ripped for trying to sort out what happened to my car. Bottom line is - the RPM/speed ratio has changed and I haven't done any mods to it. After giving it a good listen, I do think that at 70mph the engine sounds pretty normal to me. I can overlook the 70mph/5250rpm thing. However, the vtec does engage somewhere in the 80s instead of the 90s like before. This tells me that the vtec is kicking in when the tach says it's time and not the speedo. Apparently it gets the signal from the VSS (not the actual tach). I'm not getting any code from the ECU telling me that the VSS might be bad. If it's an electrical issue, do you have any suggestions?

 

its wiring...i stated this before. your cel came on...then you noticed the tah reading a diffrent measurement then what you noticed before. its not the tach...its not the o2 sensor. you have some wiring bugs that you might want to explore first. my guess would be this since you probaly arent throwing a code anymore correct? look up how to put a b16 into your crx.....follow all the wirring diagrams. sorry to be a moron towards you...but sometimes these questions are just dumb

 

i vote speedo~! :grinpimp: