Which sensors to use with LT8S?
 

I want to get a LT8S but im unsure about which sensors to have it configured to. I was thinking GM sensors would be the way to go, since my S4 sensors are surely out of range after 16 or so years. Hell, a new TPS would probably be more than ALL the GM sensors, right? What do you guys use?

Also, is the Microtech group buy still happening on nopistons.com? OneEyedJack PMd me saying he was organizing one. Anyone know whats up?

Yes the group buy is still going on over at nopistons so join in. Also i cant tell you the price of gm sensors, but in my eyes newer sensors are always gonna be more accurate than 16 year old ones.

Exactly why I would rather fab up a bracket for a GM TPS and re-tap threads than spend a shitload on new Mazda sensors and use a PARTIAL RANGE TPS!! How does that work anyway? The ECU reads only manifold pressure after half throttle? Doesnt seem very accurate to me.

Also, to those of you using GM sensors, can anyone give me part numbers? Or tell me which year and model vehicle they are used on? Thanks everyone.

On my car there are two tps's. One is full range while the other isnt. Last time i looked the microtech directions gave you the wire colors for the partial range one. Although it aint that hard to get the full range one wired up, i did. Anyway the tps is ony used to switch between idle and load maps anyway. But my boost controller needs an accurate tps reading and i like my datalogs to be accurate.

How many sensors would someone need on a TII? And which are they?

Well I've just been looking at the wiring diagram for an LT8s onto a 13BT and it looks like you need: Air Temp, Water Temp, Throttle Positioning, Crank Angle and Oxygen sensors. Diagram is http://www.microtechefi.com/IMAGES/w...4-5fuelign.pdf if you want to check it out.
-John

You dont NEED a o2 sensor. Its just for datalogging really, so its up to you. I did hook mine up however.

Yeah I know that, but can I use the existing (OEM) ones???
if no, which ones Do I have to replace?, where can I buy them??

there's a map sensor included in the LT8, but how many bar? Do you know a place to buy a 3 bar map sensor for microtech and connector?

'cuz people told me that : http://www.microtechfuelinjection.com/index.htm was not the real microtech website, I dont want to get screwed...

thanks a lot guys

l-p

www.microtechefi.com is the official Microtech Website.
http://www.microtechefi.com/html/LT.htm has answers to some of your other questions.
-John

NOw check it out. They have a plug in for the FD so you dont have to rewire anythign. They dont make that for the S4???

I wouldn't use it even if it is available. Most problems with old cars are wiring related due to corrosion/bad grounds. Using a new EMS with old wiring defeats the purpose. I'd rather wire up everything with fresh wire. It's really not that hard to do.

awesome that its easy. Your the man to talk to then. Im paiting the engine bay tommorow so everythign is comming out. What do i HAVE to put back in??? The harness on the driver side, the one with the battery terminal, is this in fact 1 harness the same as the one comming out the passanger side firewal. Its got a lot of connectins to the coils and stuff that the new ecu will hook up to (lt8) I want to know everythign that can go.

From some of the reading I've done...the LT8 only uses the TPS for on/off idle. Therefore, you could use just an on/off switch just the same. As for the water and air temp sensors, thats where the GM versus Mazda sensor issue really lies. The Microtech needs to be reporgramed if you want to switch those 2 sensors around as their resistance is different. The TPS can be swapped out anytime.

I'm still trying to figure out what the GM sensor part numbers are, as well as their cost relative to new mazda sensors.
So, if anyone knows, please post up.
-a

Looks like I may have found some part numbers:
GM sensors at AutoZone: SU107 and SU109 water and air temp.
-a

I am using LTX8 without air temp sensor, trouble is it works great, what am I doing wrong ? RON

The air temp sensor only has one timing and or fuel correction map. So it just wont respond to any temp corrections you do program into it for other temps.

is it necessary to buy a 3 BAR map sensor??

I know it is for haltech, but I've never got a clear answer from the microtech...

General:-
.............................
Max readable boost with standard map sensor :- 25psi (40psi avail as an option)

straight from LT8S spec sheet ( http://www.microtechefi.com/IMAGES/s...ech%20LT8S.pdf )

do you think it's the same for the LT8?

are those info true?

they have the 3bar and 4bar as an option. Ill keep the stock 2 bar for now..