Nistune Forums

When i started off with my 3076 map i was stuck for a base map and found the following very useful. it was posted up by a user "BenFenner" on the sr20 forum so credit can go to him. ive just flipped it to suit the way nistune works
next one is for a T67-25G 8cm kit with 264cams @1.5bar hopefully the above timing maps help with the bigger power SR20det's on the forum. just remember to knock 3-4deg off the main load sites to start off with and build it back up to suit your set up.

please feel free to post up other base maps to give people a starting point. i know PL has a great base map for GT28rs/2871 kicking about.

ill stick up my map once im happy with it, a few more weekends on the road should smooth it out a good bit!

I'll do some screengrabs of a few of my well proven maps and upload them here as starting points for people too. Might do the fuel maps too.

Although most SR maps tend to follow the same formula as you've used - you need to pull timing in the midrange to avoid detonation, then sneak it back in up top as VE drops off. SR's will only make good top end if you give them the timing they want. You can't run "flat" timing maps like RB's tend to use.

PL

yeh, as you say the SR tell tale map from a SR will see a dip between 4-5000rpm and build back up a couple of degree's by red line.

As a rough guide for anyone,
standard s14 turbo @ 1.1-1.2 you can run 10 degrees peak (4-5krpm) and after 5k to redline you can build up to the likes of 17-18deg.
in the boost transition i would run ~15deg but seen plenty of maps with higher. Some people use the engine(i.e make as much power through NA) to reduce turbo lag others rich and retard the map to get hot exhaust gas.

for larger (g)t28 style turbos at higher boost 1.4-1.5bar its very similar 9-10 degrees at peak and sneak in a couple of degrees to about 12-13 at redline. boost transition is helped slightly by the fact its more efficient and cooler charge air

above is based on UK super unleaded (98 octane)

Boost transition is certainly the area where they differ. I have a pretty standard tuned IGN map that I use as a starting point and it doesn't usually change too much. Except in the boost transition area.

I traditionally try to run as much timing as possible here after seeing some drastic driveability changes on a mate's car when it was an auto. He was complaining that it was just too doughy coming on boost - and with the auto it was just horrible (S13 SR20DET, 2871R + .64 hsg). We added a heap of timing in the boost transition area and really woke it up.

BUT this was an auto and bigger than std turbo. I used the same maps on a manual car with T28 and it rattled like hell on boost transition. Obviously the T28 boosts up faster, so you need to change boost transition timing to suit. This is actually very easy to do on the dyno, and I now double check this once I've done the full load tuning. It's easy to hold the car in the boost transition area and listen carefully for detonation. It's not making big HP so doesn't heat up too fast, and detonation is easy to hear in this relatively low RPM range.

Where I have failed to get a result is in adjusting timing/mixtures in the boost transition area to maximise torque. I either can't hold the throttle steady enough or a chassis dyno just isn't sensitive enough to pick a difference. Maybe this is where an engine dyno would be better. So I tend to do final boost transition tuning on the road. This is certainly an area that is overlooked by many (dare I say most?) tuners. Tuning it on the road is definitely the way to go but it takes two people and a lot of time.

PL

s200rat wrote:yeh, as you say the SR tell tale map from a SR will see a dip between 4-5000rpm and build back up a couple of degree's by red line.

As a rough guide for anyone,
standard s14 turbo @ 1.1-1.2 you can run 10 degrees peak (4-5krpm) and after 5k to redline you can build up to the likes of 17-18deg.
in the boost transition i would run ~15deg but seen plenty of maps with higher. Some people use the engine(i.e make as much power through NA) to reduce turbo lag others rich and retard the map to get hot exhaust gas.

for larger (g)t28 style turbos at higher boost 1.4-1.5bar its very similar 9-10 degrees at peak and sneak in a couple of degrees to about 12-13 at redline. boost transition is helped slightly by the fact its more efficient and cooler charge air

above is based on UK super unleaded (98 octane)

What AFRS you run with these timing numbers?

nissangts wrote:What AFRS you run with these timing numbers?

boost transistion i go for 12.5 -> 12.1 and aim for 11.5 -> 11.8 through peak torque and redline.

s200rat wrote:

nissangts wrote:What AFRS you run with these timing numbers?

boost transistion i go for 12.5 -> 12.1 and aim for 11.5 -> 11.8 through peak torque and redline.

Ok I was thinking more 11.6-11.9 with timing figures like that under load.

It's difficult (and dangerous) to try and be this specific - you can use these figures as a starting point but in the end you need to give each individual engine what it wants. There are so many things that can mess you up - fuel octane level, intercooler efficiency, variations in compression ratio, spark plug heat range, etc. etc.

I've had some cars that just detonate as soon as you try to give them timing. But one thing is for sure - the ones that make the power will be the ones that will take the timing without detonating!

PL