wiring vtec to go off secondaries

[A18A]

Hi there. I have here a F22B1 SOHC vtec. I also had a voltage regulator failure which destroyed the P0A ECU. Anyway, now my only other 2.2 litre ecu is a P39 for a F22B DOHC non-vtec. That F22B had secondary butterflies in the intake manifold whereas my F22B1 does not. I was wondering if I would run into any problems using a relay to wire up what's supposed to be the secondaries solenoid to the vtec solenoid instead?

I guess another important question would be, at what RPM does vtec kick in y0! on a P0A F22B1? and when do the secondary butterflies open on a P39 F22B?

I don't really like how the F22B1 doesn't really rev any higher than 5000rpm without a working vtec, but don't want to drive around all day with vtec engaged haha. I also have a budget of around $0 lol

[GhostAccord]

I would assume that the IAB's operate around the 3500-4500 rpm range???? That is where the H23 is set for anyway. That might be a bit high for an F22B1 VTEC engagement point. The stock P0A VTEC engagement is 2300/3200 rpm. Also if you are going to wire the p39 IAB for the VTEC engagement. You should know that on the JDM ECU the IAB is circuit is a (+) signal. It sends out the signal. Where as the USDM IAB circuit is a ground.

As for your 5000 rpm limit. As long as you have an operational ECU with no DTcodes stored (CEL). The engine should rev above 5000 even without VTEC hooked up. However, it may not run the best on 4 intake valves. Without VTEC the secondary intake valves only open enough to keep fuel from pooling behind the valve. Only when VTEC is engaged does the second valve open fully.

[deevergote]

The ECU is not programmed to fuel for VTEC operation, so I wouldn't suggest trying to run the P39 and activating VTEC in any other way. It could do damage to your engine, which would result in a far greater expense than simply getting another P0A!

One option is to go into the Classifieds and offer your P39 in trade for a P0A. P0As are common in the US, and the F22B1 is a turd of an engine... so nobody really uses it here. The P39, on the other hand, is hard to come by... because we never got the F22B DOHC here, and the ones that are imported rarely come with ECUs. Someone here would probably be more than happy to take a trip to a junkyard to find a working P0A to trade! (keep any such transactions to the Classifieds, though... posting elsewhere will get your thread deleted, and may get you and those involved banned.)

[GhostAccord]

Ah the voice of reason

[deevergote]

Sometimes the best answer isn't HOW to do it... it's if you SHOULD do it!


If someone asked me how to fit a Jalepeno up their arse, I feel it'd be best to advise them of the dangers, rather than handing them a tube of lube... then again... that could be feakin' hilarious to witness...

[A18A]

lol yes, that's pretty much what I meant ('should I' instead of 'how can I')

As for your 5000 rpm limit. As long as you have an operational ECU with no DTcodes stored (CEL). The engine should rev above 5000 even without VTEC hooked up. However, it may not run the best on 4 intake valves. Without VTEC the secondary intake valves only open enough to keep fuel from pooling behind the valve. Only when VTEC is engaged does the second valve open fully.

that's what I thought too, but I wired the vtec solenoid straight to the battery for a laugh & to see if it would do anything, to my surprise it actually revved higher & more smoothly (also louder lol) to past 6000rpm. not that i actually plan on regularly running the car at those revs

The ECU is not programmed to fuel for VTEC operation, so I wouldn't suggest trying to run the P39 and activating VTEC in any other way. It could do damage to your engine, which would result in a far greater expense than simply getting another P0A!

One option is to go into the Classifieds and offer your P39 in trade for a P0A. P0As are common in the US, and the F22B1 is a turd of an engine... so nobody really uses it here. The P39, on the other hand, is hard to come by... because we never got the F22B DOHC here, and the ones that are imported rarely come with ECUs. Someone here would probably be more than happy to take a trip to a junkyard to find a working P0A to trade! (keep any such transactions to the Classifieds, though... posting elsewhere will get your thread deleted, and may get you and those involved banned.)

sweet, didn't know that the P39 was a somewhat sought after ECU. I'll have to go get a spare one to trade. I'm sure they will be cheaper than P0As here lol. funny that. Don't really want to give up my P39 (yet) as I plan on using the F22B it belongs to in the future. Good call on the not-programmed-for-vtec thing. That thought never even crossed my mind. ah I guess I can just nana the motor till I acquire the correct ECU

[A18A]

sweet, some good news! I repaired the P0A ecu, it just suffered a blown zener diode, replaced that and the car runs now. CEL is on, but I think that's cause of the IAT sensor. which, for some odd reason, always was a error for that