Quick Q re diagnostics lead MBE.

[shoggyraminator]

Hello, do you need to fit the resistors as below when making the lead up, IE will it work with only the three wires from end to end? Regards

http://www.thetvrsite.com/files/ecu/ECU-lead-pictu...

[JensenA]

Yes, do it exactly as the diagram. Personally I just use a bog standard off the shelf serial cable

[shoggyraminator]

cheers!

[gcpeters]

JensenA said:

Yes, do it exactly as the diagram. Personally I just use a bog standard off the shelf serial cable

isnt that a no then? as your using a standard serial cable that doesnt have the resistors?

GP

[jammy_basturd]

When you make your own lead up you need the resistors. When you use a pre-made standard lead off the shelf you don't.

[shoggyraminator]

jammy_basturd said:

When you make your own lead up you need the resistors. When you use a pre-made standard lead off the shelf you don't.

Must admit that I would not have thought that a standard serial cable would have any resistors in line, hence my question. Not sure what value the resistors are adding to the set up + why one value 1K and the other 50 ohms more at 1.05K. 50 ohms is a very small difference when you are in the area of 1K.

Surelly if they were important they would be pre inserted on the PCB?

I might make a lead up with them fitted and not fitted to see what happens, but was just curious if someone had made a working lead with no resistors.

[Ballsy]

I use a bog standard one bought from amazon or ebay(cant remember which), works fine!!

[JensenA]

I can't remember the reason for the resistors. It is something along the lines that if you use a bog standard serial cable, it prevents a certain part of the ECU from being ever being reprogrammed. However there will never be any need for that part of the ECU to be reprogrammed anyway. It's just that the special lead with the resistors is the 'proper'/'correct' way to do it.

[headcase]

The lead shown is for re mapping the MBE, that is the reason for the resistors so unless ou are remapping then you dont need the resistors.

[julian64]

The lead with the resistors prevent any possible damage to the MBE ECU bits that are used for live mapping. The damage as far as I can tell would only be caused by an RS232 lead having connected earths. A few cables you buy have all their unused pins connected to a common earth. This would be bad.

The MBE ecu cannot do live mapping as standard but can be converted to do so.

[Nickccc]

I've got the lead from MBE with the resistors, as long as you don't need to use "Easi Map" then you don't need
them. Allthough there are a few handy options within the Easi map software. If, for instance your having lambda prods,
you can dissable lambda controle, might be handy maybe.
There are a few other interesting tweaks aswell. Though since the rebuild I havn't plugged the laptop in once.

[shoggyraminator]

Someone previously has had some work done to mine I suspect. It has short induction hoses fitted and Austec racing stickers on the air filter and ECU box and there is a print off from some dyno run.

Much to my disgust the car hardly pops and bangs on the over run even with the cats off. Is there a way to use this easimap software to increase fuelling during over run to improve the matter, or is it just not worth going anywhere near this? Regards.

[Nickccc]

It could be done, though you'll need an EPROM writer.
To be quite honest, the potential for damage is too risky I
wouldn't bother unless you know how to safely remap an ECU.
I've not seen a Cerb yet that doesn't pop and bang on the over run.
Mine was mapped at Austec and it'll do two foot long flames.

[JensenA]

shoggyraminator said:

Someone previously has had some work done to mine I suspect. It has short induction hoses fitted and Austec racing stickers on the air filter and ECU box and there is a print off from some dyno run.

Much to my disgust the car hardly pops and bangs on the over run even with the cats off. Is there a way to use this easimap software to increase fuelling during over run to improve the matter, or is it just not worth going anywhere near this? Regards.

If it's not poppin' and bangin' then it may be running too rich.