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MdMa
10-09-2016, 08:46 AM
The previous owner of my car has apparently advanced the timing...

Besides a slight power increase what other potential benefits are there to doing this, and what are the downsides?

He was also supposedly running 98 whereas I am back to 91.

PhilSSStevenson
10-09-2016, 11:52 AM
The previous owner of my car has apparently advanced the timing...

Besides a slight power increase what other potential benefits are there to doing this, and what are the downsides?

He was also supposedly running 98 whereas I am back to 91.

Advanced timing requires BP Ultimate 98RON. Otherwise you might get detonation (pinging)… Very bad for your engine…


Go back to 98RON. It is well worth it. And you will get a bit more mpg.

And yes, you will also get a better acceleration feel…

Cozzm0
10-09-2016, 02:22 PM
Throttle response, increased power, improved fuel economy is also possible.

Factory timing is 15deg BTDC, usually advanced safely to 18deg with higher RON fuels. This is especially important in summer, winter not so much.

MdMa
10-09-2016, 04:07 PM
Throttle response and power increases are not even a concern for me; I'm happy with stock.

However, which would yield better fuel economy/be cheaper to run, stock timing + 91 RON or advanced timing + 98 RON.

Every now and again I find (even when I was using 98) that the car sort of "idle hunts" and once when I came to a sudden stop before reversing, it stalled.
Could this be a side effect of having advanced the timing?

Cozzm0
10-09-2016, 04:32 PM
Throttle response and power increases are not even a concern for me; I'm happy with stock.

However, which would yield better fuel economy/be cheaper to run, stock timing + 91 RON or advanced timing + 98 RON.

Every now and again I find (even when I was using 98) that the car sort of "idle hunts" and once when I came to a sudden stop before reversing, it stalled.
Could this be a side effect of having advanced the timing?


Generally higher RON fuel + advanced timing will give you better economy. I can't say on a scientific level what is better for overall cost and efficiency but when E10 is 99c, i'm going 98 ron everytime. When E10 is 124c, i'll put 95ron in. I won't ever use 91/E10.

the idle issue is related directly to the idle valve and is very common. Cleaning and proper adjustment usually fixes the issue, its just in an pain in the ass place to get to so often some fine tuning/adjustment can help the issue, or at lest stop the stalling.

sss4me
10-09-2016, 04:34 PM
run premium, take all the **** out of your car, pump the tyres up, make sure the plugs,air filter and fuel filter are all in good nick, and be happy.

MdMa
10-09-2016, 04:38 PM
Generally higher RON fuel + advanced timing will give you better economy. I can't say on a scientific level what is better for overall cost and efficiency but when E10 is 99c, i'm going 98 ron everytime. When E10 is 124c, i'll put 95ron in. I won't ever use 91/E10.

Hmm... back to 98 it is then.


the idle issue is related directly to the idle valve and is very common. Cleaning and proper adjustment usually fixes the issue, its just in an pain in the ass place to get to so often some fine tuning/adjustment can help the issue, or at lest stop the stalling.

Could you please link me to a thread/guide/youtube on this issue?

Cozzm0
10-09-2016, 04:40 PM
http://pulsar.org.au/forums/showthread.php?133-The-SR20-Idle-Control-Valves-(IACV-FICD-AAC-Air-Regulator)-Inc-guides-to-cleaning

MdMa
11-09-2016, 08:23 AM
http://pulsar.org.au/forums/showthread.php?133-The-SR20-Idle-Control-Valves-(IACV-FICD-AAC-Air-Regulator)-Inc-guides-to-cleaning

Damn... looks like a bitch!

Whilst we're here, which spark plugs would be recommended for the advancement in timing?

Cozzm0
11-09-2016, 12:06 PM
Standard plugs are fine. BKR6EIX-11.

PhilSSStevenson
11-09-2016, 02:54 PM
Standard plugs are fine. BKR6EIX-11.

Cozzm0, the Red Jett runs on BKR5EIX-11

Why? I not sure now, can't remember. What the diff between '6' and '5'?


Phil.

Cozzm0
11-09-2016, 03:22 PM
N14's were commended a hotter plug for reasons i have no idea about.

PhilSSStevenson
11-09-2016, 04:33 PM
Maybe for the early SR20 'high port' N14's… Like the Red Jett's…

Hitmanuncut
12-09-2016, 08:30 PM
Cozzm0, the Red Jett runs on BKR5EIX-11

Why? I not sure now, can't remember. What the diff between '6' and '5'?


Phil.

That's the plugs heat range, It is indicative of how quickly the spark plug dissipates heat back into the head.

PhilSSStevenson
13-09-2016, 03:09 PM
Well Hitmanuncut, that's why the Red Jett's SR20 is given new oil every 3,000 klicks…

Never had any issues using the '5' heat range…

Maybe it likes the Crane LX-91 coil?
http://pulsar.org.au/forums/showthread.php?405-Crane-LX-91-coil

How's the bushes going?

Hitmanuncut
13-09-2016, 04:17 PM
Bushes are great thanks Phil, I hope Cozzmo has a win with turning some up on the lathe. Took one into pedders to see if they manufacture anything similar but that was a no go too. There isn't any reason you would have a drama using a '5' plug as it is only one step down from the OEM spec plugs heat range. Cheers for the book also, though I'm not sure when I'll get the chance to have a read of it, too busy studying at the moment.

Hitmanuncut
13-09-2016, 04:31 PM
N14's were commended a hotter plug for reasons i have no idea about.

Just so we're all clear, the higher the number of the heat range means it is more resistant to heat developed from the engine which is a (cold plug), a lower number means it will heat up more readily and is therefore referred to as a (hot plug).

PhilSSStevenson
14-09-2016, 05:00 PM
I remember now…

As I only do very short runs, max 30 mins, once a week, the '5' is why…

MdMa
18-09-2016, 10:45 AM
I remember now…

As I only do very short runs, max 30 mins, once a week, the '5' is why…

What about for someone who does short runs everyday (my work is only 5 minutes from my house)?

PhilSSStevenson
04-10-2016, 04:08 PM
What about for someone who does short runs everyday (my work is only 5 minutes from my house)?

Five minutes…

Don't go over 3500 rpm...

Cozzm0
04-10-2016, 04:22 PM
If you're only driving 5 minutes a day you shouldn't be under 3500rpm at all, keep it up high and enjoy the 5 minutes ! haha.

PhilSSStevenson
08-10-2016, 12:39 PM
If you're only driving 5 minutes a day you shouldn't be under 3500rpm at all, keep it up high and enjoy the 5 minutes ! haha.

How could you suggest that for a beautiful SR20? ;)