I'm building a lemons car, it's a turbo f23. I'm going to buy a phearable ecu and tune this thing right so I at least have a chance at not grenading it. Can I fab up something to replace the valve so vtec is constantly engaged? Then I don't have to have a vtec ecu, less wiring, etc. This wouldn't be something you'd do on a street car obviously, it is a racecar. Is it reliable though? I need to take that into consideration since it's an endurance race. I know the vtec lobes and rockers are considerably smaller, I'm wondering if they will hold up.
Edit: I see I might be looking at the rockers wrong. The vtec arm is actually the big one in the middle, right? So reliability might not be an issue I just won't decrease rotating weight like killer cams are made for. That's not why I want to do this though, it's purely ecu related.
Edit: I finally found something on running vtec all the time. I've seen people electronically control it, I need to mechanically control it with a part made to simulate the solenoid activating vtec. The bad thing about this is the oil pressure drop, but I will be operating above normal vtec engagement point, so oil pressure should be adequate. I may even be able to make a manual valve to shut off vtec when it's idling. How does this idea sound?

 

Honestly, especially for a lemons car, keeping the VTEC system OEM is a better idea. The wear and tear on that can lobe and rocker could potentially end your weekend.

 

I could definitely see that if I was operating below 3500rpm which I hardly ever will. The valvetrain should be able to handle it if it's being oiled properly, which it should if I stay above 3500rpm, right? It's not like they could tell the difference between a vtec and nonvtec ecu and what I payed for it, they might not even know it's aftermarket, but I like to stay relatively honest. I'm not going to have the exact amount I paid lol, but in building a $500 car $25 is a lot of money and is the difference between a vtec and nonvtec ecu.

 

Its one wire. You are making it more complicated.

If you are only going to have one map anyway, you can build an RPM based switch for pennies or less from junk. The mechanical lock means you are absolutely without options. Electronic lets you run lower RPM on yellow flags, idle in the pit, start the engine with way less hassle.....the list really goes on.

 

just remember that vtec engagement using the solenoid is oil pressure dependent, and engaging it at too low an rpm wont be enough pressure to engage and will likely reduce pressure in your bottom end which wont help longevity.

I prefer to mechanically lock it rather than mess with all that.

 

It won't have power to the solenoid because the ecu won't have anything to go to it.
Yeah, I don't want to operate below 3500rpm if it's locked.

 

The solenoid doesn't care what the voltage comes from. ECU, hand switch, vtec controller or solar panel.

RPM switch schematic DIY- DIY RPM Switch Complete with pics - RX7Club.com

OR

$12 on Fleabay, set your vtaak at whatever point you want and it comes with a blinky light. -http://www.ebay.com/itm/1000-11000-Adjustable-Tachometer-RPM-Tacho-Gauge-Shift-Light-Lamp-Red-LED-TM-/251792211381?hash=item3a9ffc3db5&vxp=mtr

 

Using only a single rocker pad with that much movable mass will no doubt cause more wear on the pads, and the cam lobe itself.

If you wanted to mechanically engage the entire rocker assembly, take the small pins and return spring out of the rocker assemblies, find the OD, and machine a longer replacement rod. You'll need a reasonably high quality steel rod, but that would be all you really need. After that point, the VTEC solenoid will do nothing but flood the rocker shafts with oil, which should be just fine.

So you'd need:

Good steel rod.
A machinst to turn it down precisely, and perhaps machine to fit.

 

Last time i mechanically locked it i just used a small washer and the stock pins. Put the washer under the pin and slip it back it back in then slide rockers together

 

Had mine locked for a while with a Bisimoto cam. Used some extra locking dowels I had from a spare head. Worked just fine, was a PITA to tune throttle tip-in for street driving.

BTW: The VTEC cam lobes use roller tappets on the F23, where as the primary lobes run on sliding tappets, so wear with VTEC always engaged should be minimal.

 

Interesting. I might be hooked up with a stock ecu I can chip and not have to worry. Even less money, but a few more wires.
Good info though, I'll keep all that in mind.

 

<p>The easy options are to either machine new rods that are 1 pc instead of multple pc, or put a bb or something into all of the rockers. There was someone making and selling pins for the B/H series heads awhile ago.</p><p>&nbsp;</p><p>Pretty much what you would do to lock vtec on one cylinder to check valve clearance, but do it to all of them. Then just either leave the solenoid unplugged, or make a block-off plate.</p>

 

You know that a non-vtec ecu can be easily modified to be used as a vtec ecu, right?


What ecu are you running?

 

<p>That totally flies in the face of what he is trying to do i.e. remove the electrical components and solenoid from vtec engagement.</p><p>If he uses solid pins to lock the rockers, blocks off the solenoid ports, and tunes the car accordingly, it will be exactly what it sounds like he is looking for.</p>

 

VTEC is engaged from the factory from 2400ish RPM at WOT, and basically goes from "3 valve" mode(the second intake valve is held ever so slightly open), to all 4 valves open, with VTEC only operating on the intake valves. Both primary/non-VTEC lobes are pretty small on the factory camshaft. Setting it higher would probably lose power as it's tuned around those puny lobes to boost torque/efficiency at low RPM. Operationally, it's pretty optimal as set from the factory. Under the type of environment you'll be operating it in, set it at the factory point and just leave it, you may be able to gain something by shifting it around a couple hundred RPM, but not much. You should basically never have it disengaging VTEC under road racing conditions, even with LONG Accord gears.

I don't know about your experience road racing or autocrossing, but I've had to add .5-1 quart extra of oil to avoid VTEC dis-engaging under hard cornering. My car has 550lb springs, Bilstein HD's, and runs Toyo R1R's. Just something to keep in mind with the F23A1.

And please, gut that lower plenum, stick on a big TB(the H23A VTEC 62mm one is a nice bolt on), and match the upper plenum opening. I'm in the process of gutting the lower portion of my spare plenum to try to gain some power past 5000RPM where things start to fall off.