sr timing figures advice

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blu3man
 

Posts: 37
Joined: Sun May 02, 2010 9:58 pm

Re: sr timing figures advice

Post by blu3man »

I used the above tune on track today and it was marvelous.

Thanks for all the tips PL.

One thing I did notice was post stint, I was running quite rich while driving around at walking speed. I assume it was my wideband unit playing up though due to the heat.
PL
 

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Re: sr timing figures advice

Post by PL »

Cool. Glad it worked out. Sorry, I didn't get to have a good look at your logs - been a kinda busy weekend...

PL
martinbattye
 

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Re: sr timing figures advice

Post by martinbattye »

adding too much timing in the boost transisition area will impede motor response..

the turbo motor needs to get on to boost. so we must balance PCP and EGT.

too much timing and the motor is working against itself whilst turbo is trying to boost. also colder EGT = less turbine energy.

too little timing means a very flat motor.. yet nice high turbine energy..
ST240
 

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Joined: Mon May 17, 2010 8:12 am

Re: sr timing figures advice

Post by ST240 »

PL,

I'm bumping this as to not create a new thread.

My setup: rb25/30 (controlled via rb20 ecu), hx35, 740cc, z32 maf

I like the looks of your base timing map... A hell of a lot better than the stock rb20 map. Do you think it might be a good baseline to start with for my setup? Or do you have other base timing maps you use for RBs [hint hint] lol.
PL
 

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Re: sr timing figures advice

Post by PL »

To use *very* broad terms the RB timing maps tend to be a lot flatter than the SR20. As in they don't have that big mid range hole. They'll take more timing in the midrange and a little more up top. The overall timing numbers across RPM are much more linear than the SR.

PL
ST240
 

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Re: sr timing figures advice

Post by ST240 »

Can you comment on the original rb20 base timing map? It seems strange to me. It looks like theres a ton of timing mid-RPM at low load then none above or below. It also seems fairly high in high load areas...

Could a guy fill the "hole" on the sr20 map and try it? Like i said, yours looks a lot better than the rb20 base timing map.
PL
 

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Re: sr timing figures advice

Post by PL »

Here's one I did awhile back. RB20DET with GT2860, 440cc inj, Z32 AFM. From memory it was running about 16psi.
RB20DET IGN MAP.jpg
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Here's another one - similar deal but smaller turbo so it liked to detonate. This was also done in the middle of a hot Adelaide summer in a non-aircon dyno setup. So timing figures are a fair bit lower. RB20DET with GT2530, 600cc inj, Z32 AFM, around 16psi boost.
RB20DET IGN MAP 2530.jpg
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One last one seeing I seem to be getting the hang of this inserting images stuff. ;) RB20DET, Z32/440 with a "Blitz K26" turbo and external WG. I'm not familiar with this turbo but it must be biggish on an RB20 cos it was a laggy bugger but kicked butt once it got boost. Kept delivering at higher RPM too - note RPM scales going to 7500 instead of 6400. 18psi dropping back to about 17 up top.
RB20DET IGN MAP K26.jpg
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PL
 

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Re: sr timing figures advice

Post by PL »

Just dug out the dyno curve for that last one with the Blitz K26 on it. He actually contacted me out of the blue the other day to let me know how pleased he was with the tune. "Took it to a drift practice the other day and held it on the limiter all day - went perfectly". I guess if that's your definition of a successful tune then the figures in that last map are probably OK! ;)

Please note that I strongly advise against just copying the numbers in other people's maps and using them. You've got to give each engine what it wants. Some will take more timing than others. But hopefully this'll give you some idea. It's also very important to get the load scales correct for your particular application. If it's accessing the wrong load column then everything is thrown out. It's all in the Tuning Basics guide anyway...

http://www.plmsdevelopments.com/files/n ... basics.pdf
RB20DET Blitz K26 Z32 440.jpg
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PL
ST240
 

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Re: sr timing figures advice

Post by ST240 »

Thanks a ton PL.

I realize that it's not a good idea to simply copy maps. I imagine even more so with an RB30 hybrid. I have a question tho. We ran a pretty retarded map and it seemed we had audible knock with the retarded map more so than we did with the stocker. Any idea what thats all about? I figure it was some sort of interaction with the fuel maps? Frustrating to say the least.

I appreciate the tuning guide, however it is quite vague, but it does point you in the general direction. I found the software and mapping guides to be much more useful :) .

I think i have to do some more playing around, hopefully before i kill my engine haha.

[Edit]: would you do me a huge favour and show me the fuel map correlating to that dyno pull?
PL
 

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Re: sr timing figures advice

Post by PL »

Yeah, it's hard to write anything to do with tuning that has any level of detail cos you're trying to cater to all different engines and all different people with a broad range of tuning skills. Most of my stuff is to do with SR's cos they're my favourite. The more I have to do with RB's the less I like them!

RB20DET FUEL MAP K26.jpg
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RB20DET Blitz K26 Z32 440 afr.jpg
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ST240
 

Posts: 57
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Re: sr timing figures advice

Post by ST240 »

Really :(? Whys that? They are finicky bastards lol.
LooseEndsDrifters
 

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Re: sr timing figures advice

Post by LooseEndsDrifters »

Bringing back an old topic but can anyone share thier e85 ign maps for sr20det??
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