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Re: Turbo Ignition Timing – Optimizing Performance with 3D Timing
Posted by: dryenko ()
Date: May 14, 2020 07:00AM

Hi Ken,
Love the work and the astute technical acumen behind it.
The obvious question for me is what would be the cost to have you program a a CB BB with your latest [ or recommended ] curve, if one was sent to you?
Would having a different Turbo setup significantly change the installed parameters ?
Or would this just mean changing the initial timing point ?
Say with a E flow Turbo with a non stock A/R ratio?
And with with different CFM carburators?
Q-jet , Weber 40 [ or 45 ] DCOE , or 1.5 or 2 inch SU ?
Some of these may change the rate of boost vs RPM under load.
Because of the Q available.
Lots of questions, I know, so maybe just take this to emails, after your initial response?
TIA,
Bob C

Bob C aka Dryenko
Dobson, NC 27017

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Re: Turbo Ignition Timing – Optimizing Performance with 3D Timing
Date: May 14, 2020 10:17AM

DynoDave Wrote:
-------------------------------------------------------
> The most accurate way would be to do it on a dyno IMHO
>
> But I am very partial to dyno's as I owned a Dyno manufacturing company
> (DTS Dyno's) for 30+ years. lol
>
> I have a project underway with a 180 turbo engine using a Holley Sniper 2V that I am setting up on my engine dyno right now, but it has to be put on hold unfortunately because I just retired and am moving to Az.
>
> Once I get back at it will be doing a 3d map of both fuel and spark. Should be interesting and fun.

Used your dynos a lot over the years. I used to work at Kippley Performance Engineering in Sauk City, WI, and we had one of your units.

The dyno is great for doing WOT development for making good power curves, but it's really hard to simulate "road load", especially on a water brake. That's why I suggested what I did for acceleration because the weight of the car will stay constant (minus the small amount of fuel used each run), and if tested back to back, the conditions should be extremely close between the two tests.

I've done engine development all my life, and run dynos for a living, but we get things as close as possible on the dyno, and finish calibration in the intended application for the best results.

Good luck on your project!

---------------------------------------------------------------------------------------------
You're unique, just like everyone else...

Johnny B
Central WI

Wife's '68, 3.0L, twin-screw compressor and fuel injected in the works...

Project Pressurized Pancake


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Re: Turbo Ignition Timing – Optimizing Performance with 3D Timing
Posted by: DynoDave ()
Date: May 14, 2020 02:54PM

Actually Road load is very easy to do on a Dyno even a water brake.

I know most racers are interested in WOT performance but OEM's do it all the time. You just set up the mapping program in the dyno to do Manifold vacuum vs RPM.

I also have set up a in cyl pressure sensor system set up to see the exact point of detonation on my current dyno set up.

A chassis Dyno would be second best IMHO

Acceleration tests have a lot of variables to skew data... There are Accelerator type dyno systems but they are like yardsticks when you are trying to get as fine as 3D timing maps

Wow Kippley that brings back memories I still interact with the KB group and Jason Line on projects. Small world for sure!

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Re: Turbo Ignition Timing – Optimizing Performance with 3D Timing
Posted by: 63turbo ()
Date: May 16, 2020 08:53AM

What I've thought was extremely cool about this last map Ken did was that it is based more on rev rates for the engine vs boost rates, vs different load conditions. Although the 2D version that I've been running of wild child is very impressive, it is nothing like what Ken has done. 2d wildchild is very close to using a 140 distributor curve up to 2750, and then using a 110 timing curve on top of that out to 4000, plus vacuum advance plus boost retard, although the vacuum advance is taken away much differently than a mechanical can would do, and the boost retard starts removing timing slightly before boost, and is more geared around keeping the engine safe and happy at 20+ psi than absolute best safe power at lower boost levels. Max timing is 18 degrees past 15psi... I find that the power is a thing of beauty at 20 psi, and very "rev happy" below that. I'm sure I could do better with what I have by using a 3bar map sensor and pull the timing more in line with actual boost instead of pulling extra and early like now but it is an enormous improvement over any mech based set-up.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: Turbo Ignition Timing – Optimizing Performance with 3D Timing
Posted by: kmart356 ()
Date: May 19, 2020 02:17PM

The testing continued this past weekend with very good results except for this jagged kPa vs rpm curve under boost conditions. The video camera was set to 60 frames per second so I was able to see rpm climbing and record kPa.
This just ain't right is what I thought. As the old saying goes... "two minds are better than one". My discussion with Kevin pointed me in the direction of the noisy pressure reading that can cause the MAP sensor to react this way. (pressure pick up at the "carb pad"). Thanks 63turbo! The stock turbo distributor/boost retard is connected to right side carb pad. That is fine for the analog reaction time of the boost retard but when you connect that feed to a MAP sensor you get fast digital readings and the Black Box was reacting to that spikey signal by changing timing values and exaggerating the problem.





I was going to install a vacuum/boost distribution block but wanted to try a quick fix to test the theory of "smooth signal is good". Today I copied the CB Performance Vacuum Reference Kit for dual carb VWs that pulls manifold pressure off each of the intake plates and mixes the signals with T fittings. This is likely a commonly used approach but it had just eluded me until now when trying these aggressive timing curves.

Success! With the one sided signal connected to Black Box, the kPa readings were bouncing between 12-15 kPa and varied as much as 20kPa in the graph above. Now the kPA reading is steady at idle with +/- 1-2 kPA. I expect a smooth kPa vs rpm curve (and smoother engine response) next time we go testing.

Ken
'62 Spyder Coupe
Florida


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Re: Turbo Ignition Timing – Optimizing Performance with 3D Timing
Posted by: jjohnsonjo ()
Date: May 19, 2020 06:24PM

This is still analog but many years ago I tried to use a 4" industrial 15 PSI that I borrowed from work. No dampening, the needle flutter under boost was so bad I thought it was going to wreck the gauge.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa


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