I have a lsv swap b18a block b16 head with gsr ecu (p72) at what rpm should vtec kick in? To me it feels late maybe almost 6 grand. Could it be wrong ecu? Could i use a a p28, get a vtec controller or is my problem bigger or do i not have a problem? Im just looking for some help im new to the lsv swaps i had a b16 swap in my old hatch and vtec popped at like 4,200 rpm's thank you in advance.

 

if that ecu is stock, it should be 4500rpm.

 

isnt a p72 a gsr ecu if so it should be 5500 right? also id just get a tune before you screw allt he work you just did

 

The P28 is what you want. VTEC will engage at the ideal 5200 RPM.

The GSR ECU you are using is most likely throwing codes as well because it will be looking for the IAB's which are not there.

 

The vtec switchover point all depends on your motor, and your tune.... a lot of my friends think that many LSvtec's run perfectly with their vtec point set to 4,500... but, thats not true. My friend has his B20Vtec set to 4300 and i had to have mine set to 5,800 for it to work at its best. It really just depends.

 

well at 4500 rpm's it sounds like the vtec's popping but dosnt feel like it then around 5800 it pulls hard as hell. At low rpms it fells a little slugish. A friend of mine told me to get a chipped p28 because the p72 (gsr) one is reading sensor's and thats why it feels the way it does at low rpm's and the vtec popping wierd.

 

Get it tuned.

 

I have an ls vtec.. I'm running a b18a block, b18c head (p72 gsr head) with b16 a pistons.. I'm running a custom tune, not just a stock gsr or si tune. you have a custom motor there for a custom tune should be put to use.. Your vtec should crack at whatever your tune is set, do you know if your ecu is virgin? to be honest, and some may argue.. it's better for your vtec to be a smooth cross over... you shouldn't get a HUGE boost in power when vtec kicks in, it should be smooth, that's a good thing. My B17 da integra has a chipped jdm pr3 ecu, vtec cracks low at 4200 rpms and I redline at 8800, but my vtec is super smooth, I can run between 4100 and 4300 and feel no difference, I just hear the vtec crack. The point isn't to gain power, it's to hold your power to redline.

 

its wherever your tuner sets it.

 

 

if its a stock p72 yes ur vtec is engaging at about 4500 rpms the reason you dont feel anthing till about 5500 or so is that because a gsr has IABS and they do not open till about then and when they open obviously there is more air coming into the engine and to balance the air full mixture the ecu adds more full with a lsvtec set up u probably dont have the IABS hooked up. And a lsvtec is not a gsr that being said u should get ur car tuned for its perticular setup and before you go get your car tunned id recomend getting a differnt intake manifold.

 

First of all. Like everyone said get it tuned. And no way you will not need a VTEC controller. Get a p28 and ask around for a reputable tuning shop.

 

thanks guys for all your input

 

Tuned with Hondata S300 or nothing! None of the suggested ECU's have the correct map to run an LSVTEC the right way.

 

or chrome or a stand alone or many other options. not just one option here.