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Hey there

Just a quick question, i recently bought a new turbo for my Ceff, the turbo in question is a Rx7 Series 4 front Compressor housing and plain bearing core with a rb20 turbine housing on the rear, it also has the Rx7 steel wheel too and the rear housing has been machined out to accomodate the exaust turbine.

The turbo was quite cheap so i bought it thinking that i could put it on myself and hoping that it wouldnt turn the RB20 into a lag beast.

I was just wondering if anyone else out there has dome something similar to this, what power they got, what the boost response is like, if the Rx7 hitachi HT18 (i think) turbo will actually be any better than the std RB20 one?

Also recently i had my car tuned by Dr. Drift (Sam) which was great as he tuned my std ecu and got all the A/F ratios all sorted out. only problem is that my knock sensors arent working correctly (i think) so he ended up tuning my knock fuel map instead of the normal fuel map as the ecu was always picking up a knock event and swapping maps to the knock fuel map.

My problem is that my car has started running rich again (lots of black smoke under accelaration eg running rich as it was before), i thought this might be to do with playing around with the knock sensors and maybe getting them to work again?

would it be possible to unplug the connections on the knock sensors to get the ecu to continually trigger a knock event and swap maps to the good "tuned" knock map? or can i just unplug the knock wires from the ecu to get it to swap maps? or will it just put the ecu into a different "safe" mode and not make any difference

Here is a dyno chart of before and after results, and it also shows off some of Sam's (Dr Drift's) great work

http://i3.photobucket.com/albums/y65/Ceffy_SA/Scan10001.jpg

Sorry about the long post :huh:

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Also recently i had my car tuned by Dr. Drift (Sam) which was great as he tuned my std ecu and got all the A/F ratios all sorted out. only problem is that my knock sensors arent working correctly (i think) so he ended up tuning my knock fuel map instead of the normal fuel map as the ecu was always picking up a knock event and swapping maps to the knock fuel map.

Sounds like a typical band aid solution... it's like putting stickytape over a red warning light. Oh well.

If it's a daughterboard open your ECU up and make sure there's a rubber hose or something jamming the chip into the daughterboard or it'll fall out. I think they use hope to hold the chips in in Melbourne.

When it falls out it'll run rich.

^^

Unfortunately its all we could do at the time, i know its not the best solution, but it will do until i get the knock sensors fixed in the future. i just want to get the car running on the good tune again.

I will have to have a look in the ECU tonight to see if anything is wrong.

Thanks someonestolecc

I know what you mean Ceffy_SA. I wasn't having a go at you, just that there are 2 types of people who work on cars.

Those where anything will do (or they just plain suck).. Typically their cars fall apart after some time. Then there's the other type of person who would work on their car as if it were their own, do a good job and end up with cars that function for longer than just the test drive.

I can't say what I would say because you're not meant to bad mouth businesses even if it's fact (in which case it wouldn't be defamation) on this forum.

I'd say 99% it's because the daughterboard has been installed dodgily. Hope it is - cheapest solution to fix it :D .. Good luck and let us know how ya went.

at the time of the tune was sam turning off the sensor and the car was running fine??

Hey there

Just a quick question, i recently bought a new turbo for my Ceff, the turbo in question is a Rx7 Series 4 front Compressor housing and plain bearing core with a rb20 turbine housing on the rear, it also has the Rx7 steel wheel too and the rear housing has been machined out to accomodate the exaust turbine.

The turbo was quite cheap so i bought it thinking that i could put it on myself and hoping that it wouldnt turn the RB20 into a lag beast.

I was just wondering if anyone else out there has dome something similar to this, what power they got, what the boost response is like, if the Rx7 hitachi HT18 (i think) turbo will actually be any better than the std RB20 one?

Also recently i had my car tuned by Dr. Drift (Sam) which was great as he tuned my std ecu and got all the A/F ratios all sorted out. only problem is that my knock sensors arent working correctly (i think) so he ended up tuning my knock fuel map instead of the normal fuel map as the ecu was always picking up a knock event and swapping maps to the knock fuel map.

My problem is that my car has started running rich again (lots of black smoke under accelaration eg running rich as it was before), i thought this might be to do with playing around with the knock sensors and maybe getting them to work again?

would it be possible to unplug the connections on the knock sensors to get the ecu to continually trigger a knock event and swap maps to the good "tuned" knock map? or can i just unplug the knock wires from the ecu to get it to swap maps? or will it just put the ecu into a different "safe" mode and not make any difference

Here is a dyno chart of before and after results, and it also shows off some of Sam's (Dr Drift's) great work

http://i3.photobucket.com/albums/y65/Ceffy_SA/Scan10001.jpg

Sorry about the long post :D

at the time of the tune was sam turning off the sensor and the car was running fine??

Ahh, i dont think so, i think he just burned the good tune onto the Knocking fuel map, and the A/F ratios acutally got better. No matter how much fuel he took out of the normal fuel map made any difference to the A/F as my ecu was always running on the knocking fuel maping

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