Timing at WOT?

[hammdo]

Yes, Mark tuned my VVE tables and it runs fantastic in blended mode. My blended rpm is higher due to the amount of torque I have.

Only on Coast-down does it even ‘buck’ a little...

-Don

[RobZL1]

This is an awesome thread. Mark and Don- thank you both for the input.

I tuned my VVE all the way to redline, too. Then when I put it in blended mode, WOT fueling went crazy. After monkeying with it for a week, I finally asked for help. Zeroing ALL the prediction coefficients fixed it. Now I can set my disable rpm anywhere, and it's fine. So I stuck it at 3000 and all has been good.

I tried you guys' smooth spark map on the drive home last night and into the office today. I like it. It might be a bit smoother driving than stock, but it's hard to say. I'm going to keep it, just because it looks better. LOL. You know, I was thinking- I bet if you were to plot a timing map of a vacuum-advance distributor, it might look similar to this style of map.

I still need to do some matching between main/idle/coastdown in the low rpm/low load areas, though. It is flipping back and forth between the main map and the coastdown map at low throttle input (FTC 0 to 7 to 0 over and over again). Once I get that smoothed out, I'll be good. Other than that I like it! Thanks for a different perspective.

Related side note- I wish we could control airflow or TPS entry points into FTC 7/15 for coastdown/decel. It would be nice to push it a little higher up once you have a cam (sort of like controlling DFCO entry points).

Here's the map I made following your lead:

[ABADZL1]

Are you having issues with RPM flaring high and low when slowing down with the clutch in?

[RyangAsh]

I've got 10 degrees more than most of you on e85, my suggestion would be not to play to much with the IAT timing table, it is what saves your ass. Just my opinion though.

[RobZL1]

Originally Posted by ABADZL1

Are you having issues with RPM flaring high and low when slowing down with the clutch in?

At one point I did. I think I fixed it with min airflow, though. Currently running 18 deg. at idle, 750rpm and about 10g/s airflow in the 800 rpm cell. Now it only sometimes does it for the first few minutes after I flash it, then settles in. I still haven't fully tuned idle- was saving it for last. Although this cam seems to be pretty forgiving for tuning in my very limited experience.

I'm always open to any suggestions or advice, though.

Originally Posted by RyangAsh

I've got 10 degrees more than most of you on e85, my suggestion would be not to play to much with the IAT timing table, it is what saves your ass. Just my opinion though.

Wow. So you hit 29-30 degrees of DELIVERED timing on e85, after all adders/subtractors/multipliers have been applied? That's higher than I've ever heard on these cars. Usually I have heard of 24-26 degrees to be typical on E.

[ABADZL1]

This fixed my coastdown oscillation.

[RobZL1]

Originally Posted by ABADZL1

This fixed my coastdown oscillation.

Thanks. Makes perfect sense to copy the main one into there. I hadn't really touched the coast tables yet. I just relaxed the main one a bit in the lower error cells so far. I'll give it a shot.

I did some spark table matching to get the spark variance to calm down when it was jumping between tables at low RPM and low throttle for my drive home. It's better- still needs one more pass probably.

I'm also still getting some cam "nibbles" when cruising around the 0.16-0.28 areas below 1800 rpm. I tried adding a few degrees of advance, but it didn't fully fix it. I'm going to try to add a couple more degrees and see where I land.

[DrkPhx]

Originally Posted by RobZL1

At one point I did. I think I fixed it with min airflow, though. Currently running 18 deg. at idle, 750rpm and about 10g/s airflow in the 800 rpm cell. Now it only sometimes does it for the first few minutes after I flash it, then settles in. I still haven't fully tuned idle- was saving it for last. Although this cam seems to be pretty forgiving for tuning in my very limited experience.

I'm always open to any suggestions or advice, though.



Wow. So you hit 29-30 degrees of DELIVERED timing on e85, after all adders/subtractors/multipliers have been applied? That's higher than I've ever heard on these cars. Usually I have heard of 24-26 degrees to be typical on E.

Actually 28 degrees at WOT or so is very common when running E85 on these cars.

[RobZL1]

Originally Posted by DrkPhx

Actually 28 degrees at WOT or so is very common when running E85 on these cars.

I stand corrected. 8 extra degrees is pretty awesome. Corn for the win!

[cray z1]

Ryangash, 28 degrees is impressive, approx how many degrees of timing are being pulled on average by your IAT tables?
My tuner has me at 22 degrees with 100% meth and 94 pump at high 70’s low 80’s temp still pulls 1-2 degrees of timing. I need to make some passes and increases from. I hope to squeeze a few mph in future with a couple of degrees more possibly.

[RobZL1]

Just to close out my thread-jack, here's where I landed on my main map after spending some time getting the low load areas better, and getting the transitional stuff sorted between the idle and coast down tables. Only has very minor 'surge' if you can even call it that, when it's at very minimal throttle input.

[RyangAsh]

Originally Posted by RobZL1

At one point I did. I think I fixed it with min airflow, though. Currently running 18 deg. at idle, 750rpm and about 10g/s airflow in the 800 rpm cell. Now it only sometimes does it for the first few minutes after I flash it, then settles in. I still haven't fully tuned idle- was saving it for last. Although this cam seems to be pretty forgiving for tuning in my very limited experience.

I'm always open to any suggestions or advice, though.



Wow. So you hit 29-30 degrees of DELIVERED timing on e85, after all adders/subtractors/multipliers have been applied? That's higher than I've ever heard on these cars. Usually I have heard of 24-26 degrees to be typical on E.

PM'd ya

[RyangAsh]

Originally Posted by cray z1

Ryangash, 28 degrees is impressive, approx how many degrees of timing are being pulled on average by your IAT tables?
My tuner has me at 22 degrees with 100% meth and 94 pump at high 70’s low 80’s temp still pulls 1-2 degrees of timing. I need to make some passes and increases from. I hope to squeeze a few mph in future with a couple of degrees more possibly.

On a 40-140mph pull after I switched to a varimax hx pump..it isn't pulling much timing at all even on hot days here in Kansas City. .5-2 degrees. At the times we actually go racing its pulling no timing and seeing more than 28 degrees... my suggestion is to get a hold of Ted Jannetty ...fueling has to be spot on to see these timing numbers..