Memcals: Knock sensors and limp home resistor packs

[greenfoam]

I'm sure I remember Bob or someone saying the actual sensor was the same part Chuff, but better ask him incase I have brain fade.

SlickHolden, I think the Fords have a more tech limp home where they cut cylinders and all sorts of things if they are overheating :O, the older Commodores just go into a budget backup spark and fuel mode when the main program breaks or something serious goes wrong

 

[Chuff]

I'm sure I remember Bob or someone saying the actual sensor was the same part Chuff, but better ask him incase I have brain fade.

My understanding was that the frequencies of the block are unique to the block, and as such you must use a knock board specific to the block, but I have also recently read that V6 knock boards work with the V8. I'm confused.

At the end of the day I'm looking for a cheaper alternative to monitor knock in my V8 without having to buy the HSV V8 memcal for around $200 when all I want is the knock board. A V6 memcal with a V6 or V8 knock sensor would be a much cheaper option.

 

[greenfoam]

Chuff from what I understand it's the Knock board inside the memcal that's different, not the knock sensor on the engine. But TTVN has tried the V6 knock board in his V8 and it works, maybe slightly different but works. So it does sound like the ideal cheap way out of the problem

 

[Chuff]

Cool, I'll borrow a V6 memcal and stick it my ECU, grab a knock sensor from Pick-A-Part, wire it up & give it a go.

Man, if this works I'll be wrapped.

 

[Immortality]

I'm sure I remember Bob or someone saying the actual sensor was the same part Chuff, but better ask him incase I have brain fade.

SlickHolden, I think the Fords have a more tech limp home where they cut cylinders and all sorts of things if they are overheating :O, the older Commodores just go into a budget backup spark and fuel mode when the main program breaks or something serious goes wrong

i know my old VK with the ESP ignition unit had a limp home mode, from memory all it did was leave the ignition at it's base timing with no advance, enough to get you home

 

[TO4355]

the knock sensors are the same for both the v6 and v8

you cant just throw in a v6 memcal without reprogramming it as it will be too rich and the ecu wont know whats going on as it has 8 input pulses instead of 6 and the maps will be all over the place

if you reprogram the v6 memcal with a modified v8 binary it will be fine
however the stock v8 binary on a v6 memcal will be too rich as the resistor packs or netres are different

you will need to lean out the binary to make it work properly its not a simple plug and play

im tinkering with the v6 memcal cores as u can get them for almost nothing where the v8 ones still cost a few$$$ to get onto

the knock board works fine as if i put an extra 5 degrees in it it loses power but cant hear pinging so thats good enough for working for me

i did a mates vp 5L on the weekend its got a 200,000km 5L with a 3" exhaust.......stock cat and engine pipes and we put a hsv style airbox k&n panel filter and 70mm t/b on it

after 20 mins of tinkering with the wideband AFR meter and MR ostrich we have a modified binary setup to run hard on a V6 memcal core

burnt onto an old vn v6 memcal and has been screaming since

 

[hakhawk]

just a query, why wont a stock v8 binary work on a v6 memcal? the tune will be fine, its only the limphome mode that will run weird.

as far as i know, the netres ic's have nothing to do with the binary while its not in limphome mode, as when i first started playing with memcals, i tried a memcal with th netres resistors and knock board unsoldered, so only the eprom was in the memcal. it ran fine, but obviously if eprom plays up, stops working, etc, the car simply stop running.


is the modified v8 binary solely to allow the knock board work properly?

 

[TO4355]

i have several memcal cores modified with sockets to swap eproms quickly

u can have an eeprom with a v8 binary on it and put it in a v8 memcal and it runs fine
swap the eeprom to a v6 memcal and it runs richer right through the rpm range

i assumed that in the beginning they would all run exactly the same just as i assumed that i could use the v6 memcal with the v8 binary and that only limp mode would be affected but i was wrong and just posting up what i have discovered

i found this out while dyno testing some different combos and couldnt work out why the factory BKBK program was so rich............turned out to be the different netres for some reason cos as soon as i plugged in a factory v8 memcal all was good............live and learn i suppose

the netres seem to affect more than just limp mode......im interested to know if vl400 or others know why exactly

 

[hakhawk]

very strange indeed, could you try a v8 binary on a memcal socket with netres resistors removed, see what differences it makes on the dyno?

might throw vl400 a email with a link to this thread, see if he can shed some light on it for us

 

[TO4355]

iv got some old pulsar memcals i might remove the netres and see what happens to the mixtures

i thought it may have been a crook memcal but i tried the same binary on 2 v8 memcals and 2 v6 memcals with the same results

they still run ok but not 100%

also noticed that
part throttle low rpm was rich
med rpm med throttle was ok
full throttle low rpm was lean and from 4000rpm ish up at full throttle was really rich as in 10:1 afrs