Recently, I just got a motorswap with auto to manual tranny conversion. Compared to my previous stock D15 engine, this is a really big change.. (B18C) So right now I'm kinda feeling curious and concerned about my car. I find that on my car, I think VTEC kicks in at 4900rpm. Is it similar with other high performance engines? btw, I have the SiR tranny installed.

I do know what VTEC is from the basics.. but I want to know what I have to be aware about it. So when your VTEC kicks in, you can't keep it up for a certain amount of time or else your engine will go. Is that right? This is what I heard from someone, but I'm not to sure. I know Honda/Integra cars have pretty high rpms. Say if you are driving on highway, how would one control from going into VTEC all the time (just driving normally)?

Also just wondering... what is your RPM at when you are speeding at around 100km/hr? (for auto drive or 5th gear for manual drive?) I think most cars be at 3000rpm going 100km?

Any details or advices would be appreciated.

 

Just be smart. I drive every day at 100 mph down the freeway just barely above 5K in VTEC. It's not a big deal, just don't abuse the car. Drive it like any other normal manual car. Don't beat the hell out of the car for no reason, but at the same time, don't worry about it, don'tbaby the thing. Run it out every now and then.

 

VTEC=all day long!!!!!!!

oh btw... https://honda-tech.com/zeroforum?id=34


[Modified by BlueR, 9:20 PM 5/28/2002]

 

Ok.. just wondering. Thanks for the link. My friend just told me to post in here.

Today, this would be my third day driving stick shift... since my auto tranny has been converted to manual shift.

By the way, this is a 1994 Honda Civic EX Sedan.


[Modified by sweetcivic, 6:24 PM 5/28/2002]

 

From what I understand is, sweetcivic got:
- B18C5 short block
- USDM B16A head
- USDM B16A tranny
- An OBD1 ECU but she didn't tell me which

She is kinda worry that the VTEC kicks in too early. Hope my info helps on solving her problem. TKS!

 

spoonek4, thank you

 

Your VTEC kicks in at 4900? Do you have an aftermarket ECU. The VTEC on my buddy's SIR kicks in at different ranges, sometimes it kicks in at 4600, then sometime it kicks in at 5500. Can anyone explain this?

 

U're welcome...

 

check the a/f ratio if your worried about vtec changing over too quick. It is possible that if the vtec is changing over and your running too lean it may cause serious problems. You should be ok though. Don't baby the vtec, it wants to be used like a 2 dollar hooker. Just make sure to use synthetic oil and don't let it run dry. Keep the engine rev happy but dont bounce of the rev limiter all the time and you'll be fine. Have fun.

 

Thanks for the comments advices you guys. It's a big change for me from a non-vtec motor to a vtec motor. And I never driven a vtec car before. So I'm still a bit new at this. I think I found a few answers from a few friends as well.

^_^

 

Same here. I have a chipped p-28 and when I first dyno'd it (by itself) the Vtec kicked in @ 5300rpm. Then the other day I sold my vafc and ran the ecu by itself again and the Vtec kicked in @ 5500rpm. Weird.

 

I think he's confusing the secondary intake runners opening with the cam switchover....

 

even with that, the 2ndarys dont open up till 5700 under 'normal' conditions, and shes thinking its at 4900? who knows.

BTW, nuthing wrong with bein 'in' vtec just watch the oil consumption


[Modified by hybrider93, 1:58 PM 5/29/2002]

 

That's what I was told.
Well, ok now I just found that my RPM is 3000 when I'm at 90km

 

The VTEC engagement point is also throttle dependent from what I understand. WOT will make it engage at a lower RPM.

 

It sounds likely that the ECU is from a B18C1. The VTEC switchover on those is between 4400~4900 RPM (throttle position dependant). Of course, there are no secondary intake runners if you're using a B16 type head, so that is moot.

As for VTEC being harmful, no way. That is some bad info there. Now running constantly near redline would not be good, but sustained VTEC operation is nothing harmful.

If you've got a 99-00 Si (SiR) tranny, I'd suggest swapping the 4.29 final drive for a 4.40 from an earlier B16 or B17 (the B18C 4.40 will not fit).


[Modified by MK Ultra, 8:14 PM 5/29/2002]