Hey guys,

Just purchased a vafc with frog harness for my 00 s2k. I had two main questions. First, Ive read some issues with changing the vtec engagement point using the vafc. Ive read if you were to stay in vtec for more than 10 sec, it might through a check engine light or kinda stall.

Also, regarding the partial throttle and the ecu over a week period taking over the settings, Ive read that one can remove the ecu backup fuse and run the car without it. This in turn will never store the cars settings once it shuts off. Would this work in compensation for the partial throttle settings using the vafc. Has anyone tried this.

If by chance this doesnt work, I'm going the route of just tuning the WOT on the vafc.

Thanks for any input.


Update:

Well, changed out the spark plugs which were pretty beat up.

Noticed with these plugs that they were gapped at 52 for some reason .

I replaced it with denso iridium gapped at 44..

Then off to the dyno..

Have an 00 with a K&n FIPK and testpipe. Dyno graph will be posted up next week, printer was out of ink at the shop.

My base dyno was 194... I thought, that was pretty darn low. With my mods was at least hoping for around 200 but Ive heard diff dynos give diff numbers. This was on a dyno jet..

After 28 passes on the dyno, my final run was at 211.4. Almost 20 hp to the wheels. I was pretty excited except for the dyno plot. I thought I would have been able to get a couple more horses since after 8400, the hp drops. NOt as bad as the original dyno stock but still drops. We tried to lean it out after 8400 but after a certain point, didnt do anything.

My whole a/f ratio was around 12.5 and some low 13's in some points. But tried increasing some points to mid 13's to high 13's and it didnt benefit me.

My vtec engagement went to 5000, we saw some hp gain even at 4600 but it was minimal. The funny thing was that I thought I would lose hp going that low without being s/c but I didnt. I kept it at 5000..

So, in the end, for WOT, the vafc is a great buy and for a total of 300 with tune and part, I think it was a great investment.

Ill post the dyno as soon as I get it so that everyone can see...Thanks for all your help to my prior vafc post..

 

get it tuned by a professional they will know exactly what to do


did you get the vafc 1 or II? You can set-up the II to only make corrections on WOT, that way you never have to reset your ECU. Also yes, there is a setting to drop V-tec, but you will only want to drop it to around 5600 RPMs and do some fuel tuning to get the most out of your car.!

 

I have the VAFC1 but I belive both of them let you adjust low and high settings. Ivr read the best settings to use by gernby is 80,81 so that the vafc does not adjust any partial throttle settings.

I was thinking of dropping it to 5700 but after reading some prior post, I'm not sure if this is something everyone experiences with the vafc when lowering the engagement point. If thats the case, I dont mind leaving it the same as stock.

 

I don't know of any issues with CELs if you remain in VTEC for 10 seconds. Doesn't mean it's not true, I've just never heard of it.

 

i know i'v stayed in vtec for more than 10 seconds with no problems

 

Thats good to hear. I didnt hear about it much but did find some instances of it occuring.

And just to get some basic info on the vtec settings. If you dont want to use the partial throttle, you should set the low and high to be 80,81 with the partial throttle settings being all 0 and the WOT settings being tuned.

Does that seem about right..

 

I've run for 20 minutes at a time with VTEC engagement set to 5000 rpm's.

 

Great.. Thanks for all the positive feedback for lowering the vtec engagement.

On a car with intake and testpipe, whats the norm you have seen s2k members lower it to. I was thinking around 5700. But ive seen some members lower it to 4000 which I see kinda pointless but if it makes power, I guess its ok.

Voodoo, are you stock?

 

Don't tune it yourself unless you own a dyno so you can see where the engagement should be rather then the ricer way of guessing where it should be.


Don't leave the fuse pulled, that means your car will always be learning, in other words running sub-par ALL the time.

 

A VAFC is only as good as its tuner. A good tuner can get you some good reliable gains. An inexperienced one can leave you with burned valves/pistons if they don't know what they are doing or have the equipment to sniff the air fuel mixture.

VTEC cross over can give a very flat power delivery curve if the tuner knows what they are doing and give a healthy boost (15-20whp) in the 5-6k rpm range.

Many of us run in VTEC for extended periods...20-30min is no problem...so long as you have oil.