Learn to tune your own car

[Alchemis]

yeah.. it's bouncing up and down when i throttle it hard.. when i do it the mild way... it doesn't bounce...

i believe my turbo-exhaust gasket is bad... causing me to have some minor exhaust leak somewhere down there that causing the turbos to spin un-even motion.

damn..... sound like it's time for a turbo rebuild... this time porting the turbo is a good idea.. allowing fast spool and better wastegate control :P

 

[Alchemis]

oh yeah my boost controller.... internal powerFC boost controller :)
it wasn't like that before... i believe wear and tear is unavoidable.

 

[SomeGuy_sg]

Interesting problem. Try a slow WOT. does the boost still spike ?

 

[Alchemis]

slow WOT....
which means the peddle does not all the way down.....let's say 50 % throttle..
it doesn't spike... and does not fluctuate...
when doing a fast WOT
100% peddle all the way....
even below 4K RPM it fluctuates when more than 0.5 bar boost...
the turbine sound fluctuates as well not just the boost reading...

this points me to the turbine is weak... because

if the turbine is okay... the boost reading fluctuates means somewhere inside the engine is leaking vacuum... and the turbine whistle sound solid and does not fluctuate...

either the fins or the gasket seal is bad in my turbos... leaky exhaust in them....

 

[phat7]

i would suggest that you look at both the vaccum boxes on the top on engine and the other behind the power streering pump.

 

[Alchemis]

after this tuning session.... the car difficult to start...sometimes can sometimes cannot.... my old man blamed i tuned the car wrongly....

now engine blown :P unable to start totally... the plugs are soaked with water...
death of o-ring... cost me RM150 tow back the car from Aman Suria.
next step.. rebuild.. mild street port... new o-rings, new apex seals, if my housing still usable, i'll use it....inspect my water pump as well.

now my old man blame me for tuning the car with dev....

what else i shouldn't miss when rebuilding ?

 

[jasonlel]

Oh no... Sorry do hear that dude. Darn...

after this tuning session.... the car difficult to start...sometimes can sometimes cannot.... my old man blamed i tuned the car wrongly....

now engine blown :P unable to start totally... the plugs are soaked with water...
death of o-ring... cost me RM150 tow back the car from Aman Suria.
next step.. rebuild.. mild street port... new o-rings, new apex seals, if my housing still usable, i'll use it....inspect my water pump as well.

now my old man blame me for tuning the car with dev....

what else i shouldn't miss when rebuilding ?

 

[- D i a b l o -]

ehem ehem..BRAPBRAPBRAPBRAPBRAPBRAP..renngggg!!!!! *ching*.... 500horsepower.?

All the best on the rebuild project CB.you gonna need it mate!

 

[phat7]

I got your message this morning. Its sad to hear the engine blew the coolant "o"rings. Wondering though what caused it? Fuelling was the same as before. We only stabilized the boost response, idling and advanced non boost timing figures by 1 deg. Water temp was good at 87C, Intake temps at 45C-60C and knock at max 40 under load. This things should not have caused any kind of water related damage. Oh well so many factors to look at. Please tell your dad tuning does not necessarily cause coolant o'ring damage but rather other factors like previous exposure to cracked radiator and ast could amount the coolant system on its last legs.

This is part of the reason i'm very hesitant to help because the blame will always be on the samaritan. Oh well. Do tell us what you plan to do.

after this tuning session.... the car difficult to start...sometimes can sometimes cannot.... my old man blamed i tuned the car wrongly....

now engine blown :P unable to start totally... the plugs are soaked with water...
death of o-ring... cost me RM150 tow back the car from Aman Suria.
next step.. rebuild.. mild street port... new o-rings, new apex seals, if my housing still usable, i'll use it....inspect my water pump as well.

now my old man blame me for tuning the car with dev....

what else i shouldn't miss when rebuilding ?

 

[Alchemis]

yeah can't avoid it as you know that older generation people doesn't speak so much about facts and explanations.
but he never bugger me anymore i explained to my mom that listens to me and she translated it :)

now get back to the plan.......

1) strip the engine and determine the root cause of failure
2) determine what must be changed
3) determine what needs to be changed when it's stripped down regardless good or bad to safe guard future
4) source for a 99 spec turbo as i know that my turbos are tired
5) i might need dev's Y pipe if he got it back....
6) mild street port
7) what kind of Apex seal to go for ? Hurley ? Atkins ? or just OEM Mazda 2mm ? or any aftermarket 2mm ?

 

[Alchemis]

okay... as you all know, my car is ready....
i got my datalogit i got my Wideband.
let me show you all some pictures about tuning the engine.

1) use datalogit to do a map watch on your AFR in a 20x20 grid... it's something that outside dyno tuning folks unable to provide you that accurate.
below is my log run. but as u know, still running in... thus i'm only tuning on the cruise side only.
http://img406.imageshack.us/img406/4568/mapwatchlu9.jpg

2) take a sample 20x20 target AFR map... this is something that what you want your car's AFR to look like. this is my target. as you can see it's pretty lean on what i want to run.... according to my information googling and also rx7club.com our car can run safely on cruise of AFR 16.. but my balls not that big i set it to 14.
http://img133.imageshack.us/img133/1129/targetafrrn3.jpg

3) the template allows calculation of what correction AFR we should plug into the INJ map after we re-cal base which reset the INJ map to all 1... less than 1 means lean up, more than 1 means richen up. below picture shows my correction map. there are some lean up and there are some richen up.. my idle now solid at 14.. very nice and clean smell in exhaust.. doesn't polute my house :P
http://img406.imageshack.us/img406/5720/correctionjn5.jpg

i'm yet to tune the boost area after i run in my car... slowly learn how to tune the IGL and IGT as well. hopefully this benefits our group of RE owners in future tuning of own car.

 

[phat7]

why is your feedback from wb in rounded numbers? set decimal places on datalogit to read from wb accurately.

 

[Alchemis]

okay.. still learning how to use that :) i'll explore more on the decimal places. probably i missed out something :)

there's one big question in my mind... does running lean around AF 14 to 15 cause too much heat on the exhaust ?

 

[phat7]

CB, when you called you asked about leaning and richening procedure. Call me again with regards to other parameters.

 

[Alchemis]

dev, sorry that i forgot to call you.. will definitely call you someday.


at the moment.... i've did adjustment, and here is my run.... i've run- in my car.. and hell i'm running freakin rich on the boost side....

http://img86.imageshack.us/img86/4810/latestafrtn8.jpg

look at the boost area on the right corner end.... super RICH... time to lean up...

below is my target AFR...

http://img86.imageshack.us/img86/5811/targetvf5.jpg

after i put in the INJ correction map and RECALC it...
i got the adjusted BASE MAP.... and due to the readings are not full map.... i've did a change which is calculate the average around the adjecent blocks and plug it in.. just incase i need to use that few blocks... else i'll be suddenly running ultra rich thus causing a big back fire or sudden stuttering. target air fuel 11.3 on boost.. currently is 9 or below..

http://img363.imageshack.us/img363/724/adjustedbasemapxo3.jpg

as you can see the BASE map is being adjusted by me... Yellow color means those boxes that i got AFR logging... red boxes means those are the ones i plug the numbers from the sky to match the yellow boxes (that has target AFR of 11.3 on boost)

soon i'll put it in and see.. hopefully i don't blow my engine running too lean...

 

[Alchemis]

blue color is i don't give a damn... never use it anyway :P

 

[Alchemis]

with all the adjusting... i managed to get results as below.... almost perfect AFR....
a little bit more to adjust... next step will be my IGL and IGL-IGT Split.. that's the crucial one... from what i can see.. my knock levels are below 20 so far...

http://img291.imageshack.us/img291/6845/almostce4.jpg