KA24DET AEM Series 1 Tune

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Joined: Thu Jun 13, 2019 11:33 am
Car: 98 r34 gtt

KA24DET AEM Series 1 Tune

Postby Brettbabin4460 » Thu Jan 14, 2021 5:24 am

Hey guys,

Purchased a highly built 240sx last season and i've noticed some significant breakup going into boost. Generally occurs around 1500-4000 rpm and then pulls insanely hard.
Car runs otherwise great, I also noticed the breakup does not occur in first gear.

I tried gapping the spark plugs (BKR7E) tighter to see if it would fix the issue with no success.

Unfortunately the one thing that the previous owner cheaped out on was the ECU. The car is running an AEM Series 1 (Yes yes I know, terribly outdated) but I was wondering if anyone had the background knowledge to give my tune a quick lookover. My previous car had a Link G4 which was insanely easy to work with and I can't seem to get any momentum with this older ECU.

Current engine mods are;

Eagle H Beam Rods
WIseco Pistons
Timing Chain Tensioners
Cometic HG
Arp Headstuds
Kelford 264's
Supertech retainers & dual valve springs
LS Coil packs.. Couple other small things that the previous owner did not mention.
Precision turbo

Car is currently tuned 380whp @ 17psi.


I am unable to find the dwell setting although was told these engines are unhappy with anything over 2, wondering if anyone could point me in the right direction as I was unable through a bunch of time last night to find anything resembling a dwell table.

Also a general checkover of the tune from anyone with experience would be amazing. The car was tuned by a shop but I'm not positive on the quality of work they put out.

Thank you guys so much!
@hfx240 on instagram if you want to check out the car any further.

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Posts: 189
Joined: Wed Apr 10, 2019 2:50 pm
Car: 1995 240SX SE - KA24DE-T
2014 Camaro SS 1LE

Re: KA24DET AEM Series 1 Tune

Postby NukeKS14 » Sat Jan 16, 2021 11:04 pm

Havent toyed w/ an AEM series 1 in AGES but I think you're a little low on the dwell value; It's not the engine but the coil that determines the dwell. You may be thinking of the stock ignition coil? and even those are different between the S13/S14.


What EXACTLY are you gapping the plugs to? I'm at .044" on BKR7E-11s on Maxima coils and I don't get any blowout up to 21psi so far. Your engine build doesn't really matter; it's the combination of fuel/air/spark that is not occurring correctly.

What are your AFRs just before this happens? can be a fueling issue. S13 or S14 here? is your fuel pump hardwired? what fuel pump are you running? What fuel pressure regulator? could be clogged injectors, low pressure, a host of things really. How old is the sensor in your wideband? unknown? may be worth it to replace for $50-70 to ensure you're getting a good reading on AFRs too. What did the plugs look like when you pulled them? What condition are your plug wires in? What fuel are you running? It's winter and winter mix tends to be a little lower octane from the additives. Ethanol tends to go down at a lot of midwest stations during winter months, sometimes as low as E60ish.

Some more ignition specific settings to compare against for your AEM; http://www.ka-t.org/forums/viewtopic.php?f=2&t=26234

Looks like dwell settings are in
ignition> advanced ING> coil dwell setup> coil dwell

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