Could anyone tell me what a good VTEC activation point is on a street/strip b16 with almost all the bolt ons?

 

the stock point probly like 4500 or sompin, too low and you will bog down.

 

if u don't have cams and intake manifold

stock....5500rpm

mike

 

I have skunk 2 intake manifold, jg 65mm TB, headers, 2 1/4 exhaust, cold air intake, cam gears, fuel rail, ground wire set, and a spoon ecu chip. what would be a good vtec activation point?


[Modified by Waachback, 5:42 AM 4/2/2003]

 

i still say stick to the factory 5500 xover......if you ever get it dynoed, where the torque and hp lines cross, is supposedly where you want vtec to engage

 

the factory vtec is 5000 for the jdm b16a

 

anyone?

 

no its not its 5500

 

my first gen b16 is 4800, hmmmmm

 

Its 5000rpm in the CRX SiR (PWO)
and 5500 in EF SiR Civic (PWO)
5900 in SiRII civic (P30)
5500 in UK/Euro VTi civic

I have owned all four and know these figures for a fact


[Modified by mugenracer, 8:34 AM 4/2/2003]

 

hmm, JDM SiR gen 2 (SiR-II) 5500..... thats what i have, thats the xover. I do not know why your saying 5900, unless your going by a stock tach or something.

 

Seeing that you didn't list any performance camshafts mods, stick with the stock VTEC x-over point of whatever your ecu is set at. Spoon PW0/PR3 ecu's usually have vtec kick on at the stock point which ranges from 4800-5200rpm.

Stock 89-91 PW0/PR3 ecu's ranges from 4800-5100ish.
Stock 92-95 JDM/US P30 ecu's kicks on around 5500rpm.


if you upgrade the cams to Type-R, up your vtec x-over point to either 5500 or 5700rpm.

The dyno will show the best results and its usually around 5500-5700rpm (with R cams).

 

LOL i would know I currently own the car so i know when the vtec kicks in. Its like 4800-5100ish on my pr3. So do u guys think a 4500 vtec kick in is too low?

 

yes 4500 is too low. I know what my car's xover is too, 5500.... and thats for a P30 jdm ecu on a jdm b16 sir-II, factory tach's are always a little off, the autometer i had read 5500 when it switched, and im not going by that only, ive read its like 5500 or 5400, but never as low as 5000 for my particular motor. But yea id keep it at whatever it is now. I've got Hondata now though so I can always change mine.

The reasoning I believe and have heard not to lower it to 4500 with your current setup would be that the B16 just doesn't have the torque to start the climb from that low, now if you were running ls.vtec or etc i would say yes 4500 would be suitable due to making more power in the middle and down low compared to the B16 making power more towards the top end.

 

yeah it is too low, it might be OK with those cams on a bigger engine, like a 18 or 20, but not a 16...

factory is 4800rpm...

t..

 

pretty sure the spoon chip hsould set your vtec for you. take it to a dyno and find out wehre you should set your vtec. where you start to lose power its wehre your vtec should be set at

 

I would go anywhere from 5200-5700... As everyone else has said if you're in the high 4000rpm range you're too low and most likely be bogging... Toss a CTR IN cam in there and put it somewhere around 5500... As Katman said you'll see the best results around there... Good Luck

 

anyone else?

 

 

stock cams I would leave it at factory specs.....larger cams you tend to move the cross over up in the rpm range....and most of your dual butterlfy motors (GSR and H22) have a lower cross over because of the volumetric effeciency of the dual intake manifold

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Kataku2K3 &raquo;</TD></TR><TR><TD CLASS="quote">I would go anywhere from 5200-5700... As everyone else has said if you're in the high 4000rpm range you're too low and most likely be bogging... Toss a CTR IN cam in there and put it somewhere around 5500... As Katman said you'll see the best results around there... Good Luck</TD></TR></TABLE>

Judging solely by 'feel,' I would have to say it feels best at either 5400 or 5600.

 

Wherever it is stock, leave it . There is no point in touching it unless you have dyno curves. Adjusting it using your "butt dyno" will probably make it worse. Here is why:

The human body feels acceleration, not speed. Your butt dyno can only tell a difference in acceleration. If you set your vtec point at 6000rpm, you'll notice a larger difference in acceleration than the stock crossover point. This does not make the car faster! It only means there is a greater difference between your torque curves. If you set your point at 1000rpm, you'll most likely feel negative acceleration (bogging). Either way you made the car slower. Dyno the car in & out of vtec, set the vtec engagement point where the torque curves cross.

So in a nutshell...

Setting your vtec x-over point should only be done with dyno charts.

 

thanks