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Got this memcal tune to look at today. Cars is a VS Ecotec with a decnt cam, ported heads, higher comp and a manual.

Nice young bloke I bumped into tells me his headers keep glowing and snapping near the manifold to head flange repeatedly so I asked him to look at the tune.

I've ID this bin as $51 VS ecotec.

Please open the bin n have a squiz. Tell me I'm seeing things cos I'm a bit effin shocked tbh

make sure you open it with the getrag xdf from the memcal ID tool, and compare it with BZPT... getrag bins have a different offset for loads of tables.

Sounds like it might be running too retarded timing in some areas possibly rich as well.

vlad01 wrote:Sounds like it might be running too retarded timing in some areas possibly rich as well.

Agreed. This guy skids his car a fair bit I'm guessing too so if it's lean up top won't be helping

tuner swapped out L67 injectors the guy had fitted for LS1 injectors

injector rate is set for 25 lb injectors, but then the fuel trims are backed off by 10% above 5500rpm. not sure what to make of it. any DTC codes? maybe its stuck in module mode spark?

Running a lot of timing up the top.


Doing a quick comparison,

Low + high octane fuel map - lots of timing
Injector flow rate
Open loop AFR target - richer
Power enrichment - richer
Cold BLM's -increased
Egnine rpm/fuel cuts increased
idle rpm Vs CTS - increased

Would need to plug the power enrichment numbers into a spread sheet to see exactly what is going on but it all looks to be a lot richer than standard.

Been cammed with some compression I wouldn't expect that much extra timing up top. Maybe they dumped in a lot of fuel to slow down the burn instead of taking out timing?

I thought it might of been richer. quite often too rich can make the exhaust glow due to it burning a whole lot slower, especially with reduced timing on top.

what was the timing like cruise to mid areas?

Yeah who really knows where the tune landed in reality..... given the cam they can normally get away with more timing than stock. Could be dodgy maf, module locked at 10 deg or a few other things. I wouldnt expect a little rich and little bit much timing to cause glowing exhausts thi it depends how long it was held near the limiter. My opinion is this tune might be close to being right but we wont know without a log.

edit: I just looked at my tune I did a few weeks ago on a dyno for a cammed up ecotec speedway car... over 20 deg timing at WOT, so they can take it when modified with a cam.
question: what do VS tunes do for spark when over 4800 rpm? the VT has an extension table. if there is something like that undefined in the VS bin, stock would be what, 12, 13 deg? on a modified engine that needs over 20 deg timing this is very retarded and could lead to exhausts glowing..

it just uses the corner cell. Then the only way to adjust from there is the advance and retard multiplier tables in power enrichment, not much to tune in those.

Personally for a VS whack enhanced on it and flick the getrag n manual flags. Full injector and spark tables.

The1 wrote:it just uses the corner cell. Then the only way to adjust from there is the advance and retard multiplier tables in power enrichment, not much to tune in those.

Personally for a VS whack enhanced on it and flick the getrag n manual flags. Full injector and spark tables.

This is what I did today. Happy days now n hopefully no more snapped headers