Unreal

I am running e30 right now instead of e55 like normal because I had to get gas the other day on the way to work.

Also it is a chilly 55F outside, so maybe it is weather.

But so far, so good.

miami993c297

That I know, but what I do not know is what was the base table you bumped by 10%...

This is a Dwell table I tuned for the D-585:



Christian

Unreal

Top table is what I bumped by 10%. Not the modifier table.

And so far, my numbers are no where near that high. They still drop off a ton at upper RPM like stock.

stevieturbo

Apparently they keep creating more spark power even up to around 8-9ms dwell.

However....Lance seemed to imply with the dwell, we should be aiming for a spark duration target or something, which can depend on lots of other factors.
Not really sure how the average person is supposed to figure that one out, but he did seem to suggest even the 4.5ms I was running might have been too much.

Way over my head that...I'll leave it at that until there is a problem, I run a little more on a friends 4cyl car, but we were trying up to around 45psi boost on it and it seemed to do so without any spark problems. I think that was only around 5.5ms, but would need to check what I left it at.

Unreal

So should I run them flat dwell vs RPM or drop dwell as RPM increase.

stevieturbo

I run them at 4.5ms throughout.

Really if anything they would require more dwell under high load vs low load. That may not be rpm dependant.

But time per firing will decrease with rpm, but even at 4.5ms that leaves tons of time in between each firing even at 7, 8000rpm

No idea how the OEM ecu deals with dwell though, there would be no need or desire to overdwell the coils especially at low loads.

Some of Lances comments towards the end of this thread

http://ls1tech.com/forums/generation...ory-coils.html

Unreal

Factory table drops as rpm increases. I'll probably just flat line it then.

stevieturbo

I guess it depends what it is dropping from and to.

And whether the tables reflect actual dwell times at the coil, or some other set of calculations going on based on the table.

miami993c297

HPTuners gives you access to some Dwell modifier table, that can be useful...

Christian

Unreal

Just loaded a tune with dwell set to 4.4ms. Will see what that does. Pretty big increase over stock at most RPM value.

stevieturbo

If that sounds like an increase...I'd query whether the numbers on the screen do actually mean that physical dwell time at the coil.

From what I gather, it's perfectly normal for most of the LS coils to be around 4-5ms ( just not the 585's )

Unreal

They are 4-5ms at low RPM and drop down to 2ms as RPM increase. the basically no change down low, with a big change up top.

stevieturbo

That seems very low up top, although I guess n/a they didnt have much need for a lot of spark or something

Unreal

So seems stronger. >4k the dwell is doubled so it should be getting more spark. Still have tr8ix at .028. Will maybe try gapping them up later.

For now, car runs damn good. Starts perfectly hot and cold, drives great.

neverstop

interesting the improvement is that noticeable. cool stuff.

Unreal

Power wise I don't think it did anything, but for idle/part throttle it seems to.