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Tuning with Dale Advance/Retard Distributor
Posted by: L L Garland ()
Date: May 22, 2019 04:41PM

I have a Dale Advance/Retard unit installed and I'm wondering if it should be disconnected when setting idle speed and ignition timing. Currently I have it connected to RH head and idle speed set to 850 and ignition timing set to 18 BDC. Just wondering if these are the best settings or would it be better to disconnect the vacuum line and reset.

Thanks for any of your input.

Leland Garland
1966 Monza w/ 180 turbo engine
Phoenix

Leland L Garland
65 Monza 180 66 4-sp
Phoenix AZ

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Re: Tuning with Dale Advance/Retard Distributor
Posted by: jjohnsonjo ()
Date: May 22, 2019 04:56PM

You want to time it with the manifold line pinched or disconnected. 18 is a good starting point with no vacuum. When you reconnect the line it should jump to the mid 20s. Now go back and add 1 or 2 degrees of advance at a time and drive, listening for any sign of pinging or knock. If the timing doesn't jump when you reconnect the line, the A/R is shot.

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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Re: Tuning with Dale Advance/Retard Distributor
Posted by: MattNall ()
Date: May 22, 2019 04:58PM

Disconnect! You want 30 deg. BTDC when idling..

As JO tells us... less than 24 at lower RPMs will allow boost sooner....

MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo




Edited 1 time(s). Last edit at 05/22/2019 05:00PM by MattNall.

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Re: Tuning with Dale Advance/Retard Distributor
Posted by: JimBrandberg ()
Date: May 22, 2019 07:57PM

The stock distributor stays at 24 BTDC initial until fairly high RPMs like cruising down the highway at 3000 RPMs. I thought the idea behind having some vacuum advance is to help in cruising situations.

If you stay with 24 BTDC initial the vacuum advance will kick it up to 30 or so at idle because it's a high vacuum situation. As soon as you accelerate the vacuum drops so vacuum advance lessens. I was worried about it but it seems to work okay. There's a way to shut off the vacuum signal at idle with a solenoid or something, I don't know about it offhand, but it's possible if you're concerned. The regular Rochesters block off the vacuum advance port at idle with the throttle plate.

If you back off the initial timing from 24 to 18 you are backing it off at high RPMs as well and losing horsepower.

All this assumes you are still using the turbo distributor. If you're using a different distributor with a different curve none of what I said applies.

If I'm off base here I'm glad to read more discussion and I'm learning new things all the time.

Jim Brandberg
Isanti, MN
CorvairRepair.com






Edited 2 time(s). Last edit at 05/22/2019 07:58PM by JimBrandberg.

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Re: Tuning with Dale Advance/Retard Distributor
Posted by: 63turbo ()
Date: May 22, 2019 09:02PM

There isn't anything wrong with 28 to 30 degrees at idle with vacuum advance engaged- if the idle speed is a little high, close the throttle stop a little more, and or let the engine idle at 1000. The idle mixture can be set a bit leaner that way, and with the extra idle timing, the throttle response is better, and the vacuum isn't so apt to fall when taking off.

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

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: Tuning with Dale Advance/Retard Distributor
Posted by: jjohnsonjo ()
Date: May 23, 2019 07:14AM

Kevin, that's a good point but it doesn't hold true for my car. I have been running 110 heads since the 70s. In my case if I advance the timing and close up the throttle I have a greatly reduced idle when I load the alternator, high beams and blower. Even if I start at 1000. It will go into the death spiral no matter how much advance I give it. There is not enough mixture going through the carb. What worked for me was using the solenoid to reduce the timing at idle and opening the carb. Much less difference between loaded and unloaded. Also when I hit the gas the timing jumps forward. Much better response off the line or coast to accelerate condition. I also added a boost retard limiting screw so I get full advance under boost. That being said, I bought a Black Box when they were on sale, just have not had the time to play with it..

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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Re: Tuning with Dale Advance/Retard Distributor
Posted by: kmart356 ()
Date: May 23, 2019 09:49AM

Both Kevin and J.O. provide excellent insights into what you might try with Dale Advance/Retard on the stock distributor.

My first tuning improvement was to use a custom 18* advance distributor (static 12* BTDC) combined with Dale A/R. The mechanical advance was all in by 3000rpm so timing was sitting between 25-30* at onset of boost. The Dale A/R would bring timing back to 23-24* under boost (still a bit low for making full power). Low end response (before boost) was much improved and boost was predictable.

J.O. mentions the Black Box. Being able to design a timing map specific for your engine and personal driving style is very advantageous. I have been running the Black Box programmable ignition (distributor locked at 0* TDC) since last Sept. The improvement in throttle response has been 5 star rated.

Ken
'62 Spyder Coupe
Florida


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Re: Tuning with Dale Advance/Retard Distributor
Posted by: L L Garland ()
Date: May 23, 2019 05:05PM

Thanks to all for your responses. I failed to mention in my initial post that my engine has an OTTO TB-20 cam installed. With this information would that affect any of your recommendations?

By the way, I do have the correct distributor for the turbo engine

Leland L Garland
65 Monza 180 66 4-sp
Phoenix AZ

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Re: Tuning with Dale Advance/Retard Distributor
Posted by: jjohnsonjo ()
Date: May 23, 2019 06:41PM

L L Garland Wrote:
-------------------------------------------------------
> Thanks to all for your responses. I failed to mention in my initial post that my engine has an OTTO TB-20 cam installed. With this information would that affect any of your recommendations?
>
> By the way, I do have the correct distributor for the turbo engine


Well you can look at numbers, but since you are already looking at timing, here's the down and dirty, there be no mechanical advance on a factory turbo distributor until 4K RPMs.

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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Re: Tuning with Dale Advance/Retard Distributor
Posted by: 63turbo ()
Date: May 23, 2019 06:49PM

I have a kind of hotter version of that same cam, and I can tell you for certain that you will never get what you should be able to get out of that cam
running the stock turbo distributor... that cam seems to want a lot of "rpm advance" like a stock 140 distributor has. The big problem with trying to add vacuum advance on top of the stock turbo distributor with the Dale unit is the
vacuum advance goes away too easy, and because of the flat timing of the stock turbo distributor, plus the boost retard leaves you hitting boost with way too little timing, and when the mechanical advance finally hits, it is way too late, especially for that cam! I would strongly recommend that you go to some sort of programable system- the easy, inexpensive, and probably the most "stock" looking (if that matters) is to get one of the "magic" Black boxes
from CB performance, as this unit programable, and can use a distributor.

One of the worst attributes of the stock Corvair Turbo's is the rotten distributor timing... the main attributes of this timing set-up is that it will positively prevent the engine from blowing up, and it does, kinda sorta work okay when loafing around... tall gear, low rpm, not quite into boost.
everything else about it is way wrong! the lack of vacuum advance causes it to run way too hot at freeway speeds... this one thing by itself can mean the difference between running at 400+ head temps and 300-320. Even with the Dale unit you wont be getting enough light load timing! for example, my Turbo runs 42 degrees at 3000 rpm, and 44 degrees at 4000 between 8" and 20" of manifold vacuum, and is ping free when I hammer it under those conditions. I think the Dale unit would be at 36 at 3000 rpm and 40 at 4000, until you hit a hill and then the true "death spiral" begins... the timing goes away too quick, heating the heads up a lot. The lack of rpm advance makes the engine feel like it has a big flat spot in it when accelerating, and then because of the "all at once"
retard feature, you get boost without any power until the late advance kicks in. With your cool cam, all those faults of the stock turbo distributor are exaggerated!

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

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: Tuning with Dale Advance/Retard Distributor
Posted by: JimBrandberg ()
Date: May 24, 2019 05:19AM

I said it wrong in my first paragraph above. What I meant to say is there is no mechanical advance cruising down the highway at 3000 RPMs, the vacuum advance gives additional advance under a light load (high vacuum) situation, which is a good thing and why you want the advance/retard unit in the first place.

I still say 24 degrees initial with the vacuum blocked off if using the stock turbo distributor, in other words stay where it was.

Different distributors with different characteristics is another story and Kevin gives good insight. My 24 degree comment is if just adding the advance/retard with no other changes. Certainly other changes would be beneficial and I enjoy reading about them.

I've always associated high cylinder head temperatures with too much advance and it's interesting to read that loafing along at highway speeds without the benefit of enough advance can cause high temps. I'd like to read more about why that is.

I haven't seen it yet but have a 180 to work on for a guy that reportedly runs fine around town but hot on the highway. Being a pilot he thinks it's all about fuel mixture. He said it didn't run hot when he swapped in a 150 carburetor. Again I haven't seen it yet but would enjoy forming some theories.

Jim Brandberg
Isanti, MN
CorvairRepair.com



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Re: Tuning with Dale Advance/Retard Distributor
Posted by: 63turbo ()
Date: May 25, 2019 08:27AM

JimBrandberg Wrote:
>
> I've always associated high cylinder head temperatures with too much advance and it's interesting to read that loafing along at highway speeds without the benefit of enough advance can cause high temps. I'd like to read more about why that is.
>
> I haven't seen it yet but have a 180 to work on for a guy that reportedly runs fine around town but hot on the highway. Being a pilot he thinks it's all about fuel mixture. He said it didn't run hot when he swapped in a 150 carburetor. Again I haven't seen it yet but would enjoy forming some theories.


Too much timing can cause high cylinder head temps, too little timing can cause high head temps, and too lean of fuel mixture can cause high head temps, and the reverse is true for all of the above! It has to do with load, and
the effects that the load has on the combustion temperature and pressure.
When timing is causing elevated head temps, whether it is too much or too little, it is basically being caused because the burn is completed with the piston too close to tdc, or with combustion temps too high. Ideally, the burn starts slow, and ends slow, but through a combination of less than ideal timing and fueling for the c.r. and load, the burn can also either start fast and end slow, or start slow and end quickly... these last 2 possibilities are the ones most associated with elevated head temps.

The big reasons why extra light load timing is so helpful on turbo's is that
load is reduced, and the engine is running more efficiently, leading to more energy being turned into work, and less being turned into heat. I found that on my car, the difference between having stock timing and sufficient light load timing was worth 50 to 100 degrees difference in peak head temps and 12-25% difference in gas mileage, but since the changes noted have all come with different combo's they aren't apples to apples comparisons.
Your head temps and mileage may vary!smiling smiley

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

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: Tuning with Dale Advance/Retard Distributor
Posted by: L L Garland ()
Date: June 03, 2019 09:14PM

I originally posted this question because I'm thinking about selling my car and I just wanted to ensure that the timing was correct. The responses from all of you are greatly appreciated and were very educational to me. I'd never heard of the Black Box and never really paid any attention to the subject of programmable timing. It has piqued my interest and I have gone back through the archives to read all prior posts relative to the Black Box and now find that I think that would be a fun project. Except for a couple things: I'm going to be 82 years old in a couple of months and I don't think I have the expertise or equipment to do a project like that.

Another question: I assume the Black Box, or something like that, would eliminate the need for the Dale A/R and the XR700 that I have installed. Am I correct in this?

Leland L Garland
65 Monza 180 66 4-sp
Phoenix AZ

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Re: Tuning with Dale Advance/Retard Distributor
Posted by: jjohnsonjo ()
Date: June 04, 2019 05:25AM

The Black Box will eliminate the need for the mechanical advance and the A/R. You would drive the Black Box with the points and could drive the XR700 from the black box or just use the BB on its own. You would need a lap top and a timing light, and possibly a serial to USB cable (cheap).


Ken sent me and others his code which is a good place to start. I'm working on my this week, but some other must do projects got in the way.


Glad to hear your still at it, I'll be 74 in a week.

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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Re: Tuning with Dale Advance/Retard Distributor
Posted by: kmart356 ()
Date: June 04, 2019 05:45AM

Leland-
Correct, no more Dale A/R. The Black Box has a built-in manifold pressure sensor which allows you to control timing during vacuum conditions as well as boost conditions - more precisely than with the A/R can.
In my installation, Black Box drives the coil directly. I don't have experience with the XR700.

If you decide to get a Black Box for your turbo, I will be happy to answer any questions on the installation and will send you a timing map file that will get you going.thumbs up

Ken
'62 Spyder Coupe
Florida


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Re: Tuning with Dale Advance/Retard Distributor
Posted by: L L Garland ()
Date: June 08, 2019 02:30PM

Ken,

I have gone ahead and ordered the Black Box from CB Performance and expect it to be here early next week. I sure would welcome getting a timing map from you -- it would be a big step in getting the BB installed. Do you need anything from me?

Thanks to you and all the others who have helped with responses.

Leland L Garland
65 Monza 180 66 4-sp
Phoenix AZ

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Re: Tuning with Dale Advance/Retard Distributor
Posted by: kmart356 ()
Date: June 09, 2019 07:27PM

Sending you a PM to exchange email address.

You do need to decide what distributor you will use to trigger the Black Box. The distributor needs to be “locked” for no mechanical/vacuum advance.

Ken
'62 Spyder Coupe
Florida


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