VTC_CiViC

Very simply, would there be any problems using say a P28 on an LS engine for tuning purposes? For example, I can write a .bin (Uberdata/Crome) for 450's on an LS, and then burn that file and use that chip in a socketed P28. Assuming I set VTEC higher than the revlimiter, would there be any other problems using this setup? I can't think of any but I figure somebody out there must have tried.. thanks

jaydmcrx

I have seen peopel use non vtec ecu's on vtec engines and just used an rpm activator switch to activate vtec. That prolly doesnt help but im sure the motor would run. Not sure how good.

VTC_CiViC

Yea I'm sure it'll run, I just wanna make sure there's not going to be any unforseen problems regarding a tune for one engine vs. another. The way I see it, I simply tune the lo-cam maps and the ECU will simply drive the car soley off the lo-cam maps all the time since it'll never see the VTEC x-over.

Pfieff

I would imagine you can just set the x-over to a high rpm then you don't have to worry about it kicking in. I know with my hondata I could just turn off the vtec x-over all together.

GimpyAccord

Inside of uberdata (or crome .. whichever you use) you simply disable VTEC by unchecking it. In Uberdata you will note that its under the "Misc" section. Then you don't need to set the xover high or anything. Its a simple 1 bit flag that tells the ecu if vtec is active/inactive... Honda did that so they wouldnt have to re-engineer every ecu.. they all share a very simular codebase. Also make sure the knock sensor is disabled if your ECU is not equiped, otherwise you'll find yourself in limp-mode hell.

VTC_CiViC

Yea it's a P28 so having the KS disabled was already #1 to do, just wanted to make sure there would be no other issues running this on a P28, thanks

Now here's something of interest. I was told some time ago that non-VTEC based ECU's (LS) actually run the same code as VTEC ECU's, they simply don't have it enabled. This being true, is it reasonable to say that one could use an LS ECU on a VTEC equipped motor and simply enable VTEC in the .bin you burn??

GimpyAccord

Theres more to it than that going the other way, but it CAN be done.. I do it all the time for people.

You must add hardware to allow a OBDI non-VTEC ecu to control VTEC. They're missing a couple transistors and some other very trivial electronics.

http://www.nitroburn.com/pgmfi...-Vtec

edit: There is a webpage for you that outlines the modifications that must be made to the various styles of mainboards used on OBDI Honda's.

VTC_CiViC

Excellent

jaydmcrx

sounds like a big payne in the butt just to ruin a vtec ecu wichever it may be.

GimpyAccord

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jaydmcrx &raquo;</TD></TR><TR><TD CLASS="quote">sounds like a big payne in the butt just to ruin a vtec ecu wichever it may be.</TD></TR></TABLE>

How is it ruining a VTEC ecu? Its still a VTEC ecu, it just has it disabled in the ROM. Its not like these are rare pieces of equipment.

omahaturbocivic

It works fine, I used my uberdata p06.bin based off the ls code on a buddys p61 gsr ecu I tested for a couple weeks and it ran exactly the same as it does in my p06. The code does not use the vtec hardware so its runs like its not even there.