i have a stock99 gsr. the only thing i did to it was take out the top half of the box to the intake. before, i couldnt FEEL when vtec hits. at 4400 rpms, i couldnt feel or hear anything. but at 5800, when the secondary butterflies opened, i could hear a difference. yesterday i put in a JDM b16 SIR ecu in my car, and now, at 5800-6000rpms, i HEAR and FEEL vtec. with this ecu, it engages vtec and opens the secondaries at the same time. i can actually feel when vtec hits, and my car does infact feel a little faster. just thought you guys might find that interesting. it was worth the money to me.

 

I would keep the stock p72 ecu on your gsr

 

Why is that?

 

Because with the butterflies open all the time, you lose torque. No need to change ECU's when the car is stock or mostly stock. It may feel like your gaining power because of the higher vtec point.

 

Keep your stock ecu.

 

 

with this ecu, the butterflies arent open all the time. they just open at the same time vtec engages, which is why it hits harder than the duel-stage p72 ecu

 

i wasn't aware the jdm b16 ecu had control over the secondaries.. only the p72 ecus. why would honda let the jdm sir ecu control the secondaries if the car that it's going into doesn't have it?

 

so you're saying that the secondaries are open all the time (even at idle and low rpms)? if thats the case, how come my car pulls a lot harder now when vtec hits than before? and if you're saying that i am losing torque by having the secondaries open all the time (if that's the case), am i gaining horsepower as a tradeoff? or am i just losing power, period? i'll take it to the track and/or dyno one day to see which ecu is truely better.


[Modified by spd18, 8:00 PM 11/2/2002]

 

I thought taking the top of your airbox results in loss hp. Something about sucking in hot air.

 

okay.. imagine a linear pull, non stop all the way to redline. you don't even feel vtec engage. now imagine a car that doesn't switch to vtec until 5600 RPM and then takes off. obviously, in the 2nd scenario you're going to feel the power transition a lot more, because you were going so slow in the first place before the vtec engagement.

 

I bet it takes longer to get to vtec now huh?

 

You lost low rpm power and gained nothing up top.

 

try drinving around with your stock ecu and drive it without hitting vtec. Then drive around with the other ecu and drive it around without hitting vtec. you should then be able to tell the difference. I think that you loose like 15 hp in the low rpm range with the secondaries open all the time. But if you like it then keep it in your car. Or take it to a dyno and get the real #'s instead of some butt dyno tests.

Just my $.02

 

okay i understand everything you guys are saying, and it does make sense. i have driven my car around with the stock ecu without hitting vtec, and i have done the same with the new jdm b16 ecu, and my car feels a little faster still (while at 2-4k rpms) with the jdm b16 ecu (over the stock). now i know the butt dyno is not accurate at all and i actually may have lost power and i just cant tell.. but my car does feel a little faster with the jdm b16 ecu (below 4k-ish rpms) than the p72. <shrug>. oh well, i'll mess around with both of them and i'll take it to a dyno to see for sure.

 

I'll tell you this much when I just had a cold air intake on my 98 GSR,I threw a remapped 95 obd1 p72 in my car and it feels faster no question.Car pulls harder during vtec no question at all.

 

how about getting it on a dyno to see if power has actually increased....instead of just "feeling" it.

 

I agree..i chip ecu's and i even agree that you should keep your stock ecu, unless you get a skunk2 IM, or a built motor. Stock cars dont benefit off of chipped ecu's. The reason why you think vtec pulls harder is because your not pulling hard in the low rpm's...by the time you get into vtec, its going to pull hard. Your stock gsr ecu will pull hard all the way through! its designed that way thats why! LOL dyno results would be nice though

 

[QUOTE]how about getting it on a dyno to see if power has actually increased....instead of just "feeling" it.

I agree..i chip ecu's and i even agree that you should keep your stock ecu, unless you get a skunk2 IM, or a built motor. Stock cars dont benefit off of chipped ecu's. The reason why you think vtec pulls harder is because your not pulling hard in the low rpm's...by the time you get into vtec, its going to pull hard. Your stock gsr ecu will pull hard all the way through! its designed that way thats why! LOL dyno results would be nice though [/QUOTE}
Yea but if you have a 98 GSR with I/H/E and throw a 95 ecu in there it will respond better to the bolt ons,maybe only 5 whp and a couple pounds of tq because the car is running less restricted you guys don't agree?That isn't worth it?

 

Converting from OBDII to OBDI might give you 5 whp. I'm not even sure if it does but doing that will set you back three-four hundred bucks as you need a new ecu and a wiring harness. With that much money, you might as well do something worth while.

 

Good exh=300to500$+labor,=2 to 3 whp
Good header=275to1000$plus labor,5 to 10 whp
Intake manifold=300$+labor,5 to 10whp
Mods cost dough.I just like to know my mods are being utilized the way the car is suppose to.

 

no, that ecu WONT control your 2ndarys, and the only reason you can 'feel' vtec more now, is because of the uneven balance in power.....go back to your stock ecu.

 

His car is stock with the top lid off his airbox. When you do a lot of mods, then its worthwhile.

 

alright i see what you guys are saying and it makes sense on why it feels like my car is faster. now my question is, if i got a skunk2 im with i/h/c/e, would the ecu benefit me then opposed to the stock? or would i still lose power (before 5800rpm when vtec hits)? if i did a b16 head swap then it would benefit me becuz with the b16 head i wouldnt have secondaries, just one stage of vtec.

 

ttt. one more question: if i got a skunk2 intake manifold would i benefit from the ecu, or would it only benefit if i had say a b16 head?