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It won't be out for a couple of months yet.

All it will do is basically reduce fuel consumption as the Microtechs at the moment are quite heavy on fuel.

There is also a possibility that the new microtech will have speed input hence traction control. Maybe maybe not. We will have to wait and see hope I guess.

Do a search for LT12 and you will find the users names.. :P

It is a good ecu just make sure when they are tuning that they don't tune the AF's on the limit as you have to leave some head room for cyclinders 5 & 6 as they often lean out. So ... Tune the af's to around 11.8 and you will be fine. Its better to be safe than sorry. :)

How much will they be? Im looking to change ecu's in the next few months. I have a M4 sitting on a bike which doesnt get used, maybee i'll steal that :P

It is a good ecu just make sure when they are tuning that they don't tune the AF's on the limit as you have to leave some head room for cyclinders 5 & 6 as they often lean out.

How does that work? How is it a microtech only thing?

Apparently the new Microtech is only going to be a couple to a few hundred more than the LT12.

With regards to leaning out of no. 5 & 6.. It isn't just a microtech thing. Look how many R33's have died recently due to to harsh tuning. It is common knowledge that all RB25DET's run hotter in no. 5 & 6. This is why when flow testing injectors you always shove the higher flowing injectors in no 5 & 6 to help cool these cyclinders down and make sure they arn't leaning out.

It generally happens as soon as you jump over the 230rwkw RB25DET boundry.

So make sure you get a AF print out on your dyno run and make sure there is a little head room left when it comes to fueling.

cylinders lean out because the injectors are blocked.

It's often 1 and 2 or 3 and 4 as much as 5 and 6. The factory plenum distributes air quite well to all cylinders but, after 100,000kms the injectors naturally enough need to come out for a clean.

On my car we had a ping at 4500rpm that did not show in the afr's (it was in the 9's). On consideration I believed it to be a single blocked injector and it turns out it was!

Imagine that. You have ultra rich afr's and all of a sudden you kill a piston.

I cleaned my injector No.1 with a foot spa and toluene, now it's all good.

That is in your case rev210.. But apparently cyclinders 5 & 6 always run hotter than the rest due to a cooling design.

You are right cyclinders do lean out because injectors are blocked but that isn't the only reason.. If you have your injectors on the limit with the stock rail. i.e running 260rwkw through stock injectors with upped fuel pressure cyclinders 5 & 6 do tend to run leaner than the rest. I am not totally sure Sydneykid explained it in a thread some where.

But that is what happens this is why you shove your higherflowing injectors in no 5 & 6.

Sorry to hijack this thread, but while were on the topic of microtechs I was wondering if there are any downside to running a LT8 on a RB20 instead of the LT12?

I bought my gts4 with it already installed and am now a bit worried as everybody with a microtech seems to be running a LT12 and not an LT8? :)

Are there any obvious disadvantages in the LT8? cos i thought the LT8 were designed for 4 cylinder cars not 6's.

Thanks, any help you can give me would be great:)

My old RB20 ran MT8, took a bit of work to get running right (could have been age of car, R31 GTSX)

Like many computers it wasnt that impressive at 1st, but once set up right it did what was asked of it.

Running them on a 6 cylinder is fine it just means you run wasted spark (3 of the 4 ignition drivers run 6 cylinders, so cylinders are fireds in pairs which isnt that big a deal in a road car)

Thats not to far off mine then.. Driving normally boosting etc.. I get 470kays to a tank but I seem to be one of the only freaks that get this type of mpg... Every one else seems to get 400 even sub 400's.

Boosting hard like the other night with the cruise I used 1 needle width under a 1/4 of a tank and did 141 kays... A big chunk of those kays was done at 180kays bouncing on and off the speed limiter so cruising on 180kays I was making 3psi boost just cruising.

I seem to get better kays on a long drive with hard driving than I do with short trips and normal driving (9kays round) driving to uni.

LTX-12 for R33 does not have closed loop. I rang them. It is already out, they just don't have enough production. They won't answer your calls in the morning anymore because they are working madly to produce them. You have to resort to calling the mobile number in the afternoon.

Microtech are at Putney in Sydney.

But they are pretuned for the R33 - you will still need to take it to a dyno real quick because Microtech said they will foul the plugs otherwise as they will run rich if you don't tune and install the air temp sensor. The pretune doesn't have the map for the air temp sensor at all. Needs to be put in while dyno tuning.

You can get R33 standard / R33 auto / and R33 GT models

If you want brand new ones for $1650 pm me.

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