The intricacies of early valver fuel injection

[randal 0]

A friend and I have been talking about VW and Honda engines, and how things are done differently - don't worry this isn't turning into a debate!

 

Anyway... I mentioned I have high lift cams in mine, and he said "have you had a remap to take advantage?"

 

My response to that was - "I'm pretty sure the KR ECU isn't mappable, as the KJet injection system is mechanical"

 

So given that engine fundamentals are the same, how is a "remap" achieved on the KR lumps to take advantage of things like cams, porting etc...?

 

ta

randal

[flusted 0]

The kr ecu only controls timing not fuelling so cant really be remapped.Instead you can have the wur mod done like i have and set co to 2%

[randal 0]

Ah haaaa, gotcha. What does your v-sam do with regards to this?

[flusted 0]

v-sam allows ignition timing to be altered across the rev range.I can basically write a map with as much or as little advance anywhere in the rev range

[Henny 0]

yeah, V-sam and K-star are basically aftermarket piggy back ECUs for the K-Jetronic system and (as flusted says) they allow you to map the timing much more than the standard system would allow you to do...

 

The only way to put a full engine management system onto a KR engine is to use electronic injectors and a full aftermarket management system... not really worth it unless you're doing something really silly like plonking a turbo or supercharger in there... ;)

[randal 0]

Haha, I wish! Sounds like an awful lot of hassle to "modernise" the KR's injection system, I can see why the 1.8T conversion has been so popular now.

 

Thanks guys, you've answered my question with bells on. Nice one. :D

[Henny 0]

yup, pick up a nice straight valver with a not so happy engine for £1200 ish, pick up a full engine conversion for £1500, put the two together and get a 250bhp sports car that looks fantastic, handles well and will embarrass a lot of much newer "sports" cars.... makes sense when you look at it that way doesn't it? ;) :lol:

[randal 0]

I would love to drop a 1.8T in there, more than anything. Something about the uniqueness of an engine conversion, and the idea of bringing an engine bay up to speed that really appeals to me - however the cost of which certainly doesn't!

 

Well, I've got a nice straight valver with a grumpy engine. Soon to have port and polished rebuilt top end to stop said strop!

[Kevin Bacon 5]

K Jet self adjusts to a certain extent but can only sustain about 200bhp, max.

 

K-star and V-Sam can't 'add' advance, they can only take it away.

[flusted 0]

not really worth it unless you're doing something really silly like plonking a turbo or supercharger in there... ;)

 

Or fitting itbs :lol:

 

I think v-sam can add advance as the first map i ran had -2 degrees at 6000rpm and the map h100vw sent me has +18degrees!!!!! :shock:

[h100vw 0]

I am sure you can advance VSAM like flusted says.

 

If you couldn't though. You could put loads of advance in with the dissy and pull out what you didn't want/need with the VSAM.

 

Gavin

[Henny 0]

h100vw, isn't that how Digifant does it anyway? 8)

[h100vw 0]

Digifant has a map in it though. It doesn't allow maximum advance all the time. There are limits built in the map. The knock sensor can trigger the ECU to retard the timing, which is what I think you were hinting at.

 

For best of all worlds you need the minimum amount of advance to get max power for the conditions. If 25 degrees of advance and 40 degrees both give the same power, then you should go with 25, any more is wasted.

 

It is possible that flusted could refine the map I created all those years ago and make it work better for his set up.

 

Gavin