[V6vintage]

Another small question:
So - my single ignition coil which serves 6 cylinders manages dwell by itself via its onboard igniter. It fires with the logic going low.

What settings do i put in TunerStudio dwell settings?

At the moment the running dwell in my tune file is 3ms. I ask because if Speeduino is adding dwell, AND the coil is adding dwell, at higher revs, is there a risk of there not being enough dwell time before the next spark event? remember the coil is quite busy feeding 6 cylinders.

I am in the middle of building a triple coilpack driver, but Farnell have sent me the incorrect components twice now - and my rolling road setup day is booked for this monday!

I just want to make sure my single coil pack is configured nicely so it is as efficient as can be.

Thanks!

[PSIG]

You should be fine. I don't know if yours is dwell time or current limiting type. Most integral coil drivers are limiting (usually current), not adding, so you can clip it shorter but not extend it so long as to fry the coil windings. Do note that current limiting modules and coils can still burn-up if the dwell commanded is very excessive. The current limiting sheds the excess current as module heat. Your dwell figure would appear to be reasonable. Some users just throw extra dwell at them and figure they will limit the current for protection, which they do, but not happily.

Enjoy your dyno day! Do not go there looking for peak HP numbers. Go there for a full high performance tune. Peak HP numbers are cheap and relatively useless. You want comparisons with each change, and overlay the pulls for improvements, not numbers. You will usually see most improvements by working on weak areas, not concentrating on strong areas. By the end, some of the most valuable info will be form the dyno operator who can identify weak areas where hardware changes (based on the dyno results) will make the best gains, e.g., restrictive exhaust, cam valve timing weak in a certain area or way, ignition timing is det-limited due to fuel, etc.

You should prep your car fully for tuning. You are paying full price even when it's not pulling numbers - so get it as ready as possible before you go. If anything needs fixing or prep, you are just paying $180/hr for them to do it for you. Full tank of the fuel you want it tuned to, fresh spark plugs properly gapped, at least 2 extra sets of spark plugs, any tuning stuff or parts to test/swap, properly inflated tires, all fluids topped-off - and any other prep you would do if you were getting ready to stage at the races.

Your engine should be running perfectly, except it's not tuned. That means no misses, smoking, knocks, ticks or anything else. Your exhaust can have NO leaks or the tailpipe lambda will be thrown off. Be sure your cooling system is in tip-top shape, as much of your time (money) is spent waiting for cool-downs, and the faster your cooling system recovers the better. Your whole drivetrain should be up to the task and ready for action. For example - do you have a properly sized cooler for your auto tranny? Is your fuel pressure regulating properly? Do your sensors calibrate well? Are there any splits, cracks, or leaks in your vacuum tubing? And so on.

They likely have a prep sheet to help you get ready. Call them for a copy. Also, be sure to get copies of as many sweeps or pulls as you can - at least first, best, and final. Take a note pad or use your phone's voice recorder for notes. Set TS to auto-log, and note what each log was for, and save tunes again noting the changes on each for later review. Have fun and post-up!

David

[V6vintage]

Ah, thank you! It runs well at the moment but the dwell thing has always played on my mind because I was unsure.

Your engine should be running perfectly, except it's not tuned.

Yep it starts and runs well, is good on the motorway but i feel it has a flat-spot. I am weary of tuning the spark myself as i have a severe hearing loss and wear hearing aids... which funnily enough filter out most detonation-type noises

I'll treat it to a new set of spark plugs, the ones in it now have had a fair amount of carbon abuse! I also have a brand new lambda sensor to go in. Exhaust is brand new too and it doesn't leak


I'm travelling a fair distance to a tuner that sounds friendly and knowledgeable.... the tuners local to me don't know how to tune engines by ear :/ they were quite honest in saying that they rip the map from the ECU, send it to somewhere on the internet, re-flash the ECU with the new map and then do a power run to check. They could only do this for factory fit ECUs obviously! One tuner said it was impossible that my engine was made in 1974

The dyno I've booked is a four wheel drive retarder type so can do steady-state RPM tuning which will be great for adjusting spark and viewing output torque.

They likely have a prep sheet to help you get ready. Call them for a copy. Also, be sure to get copies of as many sweeps or pulls as you can - at least first, best, and final. Take a note pad or use your phone's voice recorder for notes. Set TS to auto-log, and note what each log was for, and save tunes again noting the changes on each for later review. Have fun and post-up!

I should have the lend of a GoPro to see my ancient land rover on a rolling road! my dashcam should also record as it flies off the rollers and through the wall...

I've chatted to the tuners about when the allocated time slot actually begins i.e. is it after it has been strapped down or the moment the tyres touch the dyno? They said not to worry and that they are pretty chilled out and that I'll get my money's worth. They sounded quite excited to be working on a 1961 land rover with homebrew EFi...!

I will update my build thread with results... hoping to beat 138BHP as is stated with the (restrictive) carburettors.
If anything, miles per gallon is probably more important to me than peak BHP, as at the end of the day i'm driving an ancient tractor made of nothing but tin

Thanks for the input as always!

[PSIG]

They sounded quite excited to be working on a 1961 land rover with homebrew EFi...!

Nice! It sounds like your 'tuner shopping' will pay-off. A knowledgeable and thorough shop that is willing to work with your and your 'weird' system will provide much better value for your money. There is a huge difference in value from a 'quickie' shop that only tunes WOT fuel and spark for peak numbers (or worse), and one that does the real job of tuning all other operating areas including cruise, off-idle, AE, dwell, injector dead-time, etc, for a well-rounded tune that provides max power, max economy and best drivability all in one. That capability is, after all, one of the primary benefits of moving to EFI for either street or racing. It takes time, and time is money, but the investment brings much better results and value for your money spent. Or, is that invested?

I will update my build thread with results... hoping to beat 138BHP as is stated with the (restrictive) carburettors.
If anything, miles per gallon is probably more important to me than peak BHP, as at the end of the day i'm driving an ancient tractor made of nothing but tin

A good attitude even for racers, as peak HP will lose to better average HP, and with quicker lap times from better drivability. Street or race, you are looking for the same results across the entire tune. You can and should do additional tuning after they release you by reviewing those logs and tunes you saved , such as for optimizing timing advance in cruise as seasons or fuel blends change, for other features such as DFC or fuel trims, or if you change any hardware. They set the foundation with the reference data from it, and you can continue sharpening the edge of your tune from there, using that info and established data. The factory cars commit millions of dollars and months to tuning, and you are only getting a tiny tip of that, but the most important part. Hard data. Your work and improvements are only beginning.

David

[ladygaga]

The ideal dwell time for your coil pack will depend on its specific characteristics, such as the coil resistance, inductance, and saturation current. Typically, you want to set the dwell time to the minimum required to fully saturate the coil and produce a strong spark.

To determine the ideal dwell time for your coil pack, you can use an oscilloscope to measure the primary coil current waveform and adjust the dwell time until you achieve the best spark performance. Alternatively, you can refer to the manufacturer's specifications or consult a professional tuner for guidance.

In general, for a single coil pack managing 6 cylinders, a dwell time of 3ms should be sufficient for most applications. However, if you experience misfires or other ignition issues at higher RPMs, contextoyou may need to increase the dwell time to ensure that the coil has enough time to fully charge between firing events.

In TunerStudio, you can adjust the dwell settings under the Ignition Settings menu. Make sure to only adjust the dwell time if you have verified that your coil pack can handle the increased load and that the ignition system is functioning correctly.

[PSIG]

MODERATOR - Am I correct to assume these are "AI" replies with links embedded? Some appear to intend to actually be helpful (whether they are or not), but contaminated with links. Just curious.

[jonbill]

Yes, I believe them (this most recent post for example) to be bot generated from previous posts in the thread and/or phrases scraped from elsewhere on the internet that are related to keywords or concepts in the thread.
Sometimes they have embedded links, sometimes not.
I've no idea what the bot authors hope to gain either way.
Even when they appear to be harmless, I delete them. I don't think bots talking to bots on old threads is healthy.

[PSIG]

If still like days past, it is for search engine ratings. The more sites that mention one of their sites, the higher the Google web-crawl rating and higher on the search returns, and also that site valuation is often tied to the search rank ratings as another monetization. If they are not deleted, then we could be flooded as an easy site, so your work is important I think. I would much rather new members are barred from links and PMs in the first few posts, and bar links added for x-weeks (the source of re-visit edits). They hate that, saves you work, and gets our editing capability back. Thanks!

I did not mean to hijack the OP's thread. Please delete all posts in this OT vein.

[PSIG]

SPAMmer copied my reply and inserted a SPAM link... classic flipping us the bird.