Ideal amounts of CO2 parts per thousand

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pruyter
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Ideal amounts of CO2 parts per thousand

Post by pruyter » Mon Aug 13, 2012 2:11 pm

In order to get the perfect air/fuel ratio I should like to adust the carburettor of my Tiger with the aid of a gas analyser. I know that in the sixties gas analyser were not used to adjust carburettors, so obviously there is not mentioned an ideal CO2 percentage in the Tiger workshop manual. But perhaps someone has by now found out this percentage and I should be very grateful if somebody would take the trouble to inform me about it.
My Tiger is equipped with a 289 CI engine and a standard Autolite Ford carburettor. One of my friends owns a standard 260CI Tiger with also an Autolite Ford carburettor and he too wants to adjust the carburettor with a gas analyser.
So if anybody has the right figure and would be so kind to share this information with me and of course the other forum readers I would be a very happy man.
Best regards from Peter Ruyter

gtsmrt
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Post by gtsmrt » Tue Aug 14, 2012 8:13 am

Hi Peter,

I may be way off here, but wouldn't the amount of C02 produced be determined by the tune of the carburettor? You may be better to dyno tune your car to find a nice balance. That way you could see what air/fuel ratio you have across the whole rev range and make any adjustments then.

Regards, Robin.
Robin O'Dell
Tiger MK 1a
ENJOYING THE EXPERIENCE AS DAD WOULD HAVE

pruyter
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Post by pruyter » Tue Aug 14, 2012 5:33 pm

gtsmrt wrote:Hi Peter,

I may be way off here, but wouldn't the amount of C02 produced be determined by the tune of the carburettor? You may be better to dyno tune your car to find a nice balance. That way you could see what air/fuel ratio you have across the whole rev range and make any adjustments then.

Regards, Robin.
Hi Robin,

Thanks for your reply. I understand what you are saying, but I am talking about the ordinary adjustment of a standard Ford Autolite carburettor. Up til now I do it by hand en ear just as my friend is doing with his Tiger. As a coincidence I got a gas analyser of a friend who owned a garage and stopped with his business. So I wanted to use this opportunity to be sure that I adjusted the carburettor as it should. For a dyno tune I have to visit a specialist and pay for it. Another thing is the trouble we have here with petrol which is spoiled by ethanol with the consequence that after the car has been standing without using for monthes (as in wintertime) the carburettor is contaminated with something like gum. Then I have to open the carburettor and clean everything. After this job I have to adjust the carburettor again and then a gas analyser is a handy device.
Well if there is no information about the CO2 available then I have just to do it by hand as usual.
Anyhow I am thanking you for your reply!
Best regards from Peter

bigbob
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Post by bigbob » Tue Aug 14, 2012 11:52 pm

I've fitted a wide band lamda sensor in the exhaust & have a full time air/fuel ratio meter in the dash. It gives continuos reading on mixture under real driving conditions. Ideal for setting carb up correctly. Maybe over the top for a standard car though.

gtsmrt
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Post by gtsmrt » Wed Aug 15, 2012 8:18 am

Hi Peter,

If you have the gear, I would then aim for the lowest attainable C02 reading that you can get while still being road useable. From what I understand, if you are getting good fuel burn your C02 reading should be at it's lowest. I would just have a bit of a play and report back.

Regards, Robin.
Robin O'Dell
Tiger MK 1a
ENJOYING THE EXPERIENCE AS DAD WOULD HAVE

pruyter
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Post by pruyter » Wed Aug 15, 2012 4:41 pm

gtsmrt wrote:Hi Peter,

If you have the gear, I would then aim for the lowest attainable C02 reading that you can get while still being road useable. From what I understand, if you are getting good fuel burn your C02 reading should be at it's lowest. I would just have a bit of a play and report back.

Regards, Robin.
Hi Robin,

Thanks again for your reaction. In relation to your suggestion to aim for the lowest possible reading I want to add something I was reading this week in Practical Classics the wellknown english classic magazin. One of the the members of the redaction was trying to get his Montego adjusted with help of a gas analyser. The Montego should have 2.00 parts CO2 per thousand and had in reality 0.94 so its was really running lean. The comment of one of the experts of the magazine was as follows: "lean running (too much oxygen and not enough fuel in the mix) leads to higher engine temperatures. It can reduce valve life and increase engine wear. In the long run, it won't save cash".
In the Haynes manual for the Ford Mustang 1964-1973 there are given CO2 values but not for the first Autolite 2100D-carburettors. Just for the latest one there is mentioned 0.2 at idle for California and 0.5 at idle for others. Surely the severe regulations in California regarding emissons explains this difference.
What is puzzling me is: at what rpm is the CO2 measured? Is it always at idle as the Haynes manual is suggesting? I am totally new in this field and I like to learn.
So Robin I appreciate it very much that you are trying to gather some data for me and perhaps other forum readers can benefit from it too.
Thanks in advance!
Best regards from Peter in the Netherlands

pruyter
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Post by pruyter » Wed Aug 15, 2012 4:46 pm

bigbob wrote:I've fitted a wide band lamda sensor in the exhaust & have a full time air/fuel ratio meter in the dash. It gives continuos reading on mixture under real driving conditions. Ideal for setting carb up correctly. Maybe over the top for a standard car though.
Hi Bigbob,

Thanks for your reply. And yes....perhaps your solution is a little bit over the top for my humble standard Tiger. But I appreciate that you are trying to help me and that is what counts most for me!

Best regards,
Peter

martin172
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Post by martin172 » Wed Aug 15, 2012 5:44 pm

IIRC, a while back someone posted a link to a US site dedicted to SBF.

If you have no joy here, it could be worth seeking it out.
That's all the help I can be I'm afraid.

Anyone know the site name?

H, Sunny 65
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Post by H, Sunny 65 » Wed Aug 15, 2012 11:53 pm

To start with adjusting the fuel mixture on a fixted venturi carburetor only set's the mixture at idle, as soon as you move the throtle the mixture is down to jet size and air flow.
The CO% on idle should be about 1.5% +/- .5%. If you have a four gas emission tester as used in all UK MOT stations, you should aim for a lambda reading of 1.00 and a hydrocarbon around 75. Higher than 1 on lambda is running lean, lower than 1 will be running rich.
Or you can just wind the mixture screw in till it stops, and then wind it out about 1.5 turns.

Maybe some help Harry.

pruyter
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Post by pruyter » Thu Aug 16, 2012 6:11 pm

H, Sunny 65 wrote:To start with adjusting the fuel mixture on a fixted venturi carburetor only set's the mixture at idle, as soon as you move the throtle the mixture is down to jet size and air flow.
The CO% on idle should be about 1.5% +/- .5%. If you have a four gas emission tester as used in all UK MOT stations, you should aim for a lambda reading of 1.00 and a hydrocarbon around 75. Higher than 1 on lambda is running lean, lower than 1 will be running rich.
Or you can just wind the mixture screw in till it stops, and then wind it out about 1.5 turns.

Maybe some help Harry.
Hi Harry,

Thanks for your information. The device I got as a present from my friend who stopped with his garage business is a quite simple device so not a sophisticated four gas emission tester. I am aware of the usual way to adjust this kind of carburettors, it is just that I got this gas analyser that I wanted to use this opportunity to get it perhaps more right than adjusting the carburettor just by hand. So I thank you for the information that on idle I should aim for 1.5% +/- 0.5%. I am curious if I find a difference compared by the usal way to adjust this carburettor.
Thanks again Harry!

Best regards from Peter

pruyter
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Location: The Netherlands

Post by pruyter » Thu Aug 16, 2012 6:15 pm

martin172 wrote:IIRC, a while back someone posted a link to a US site dedicted to SBF.

If you have no joy here, it could be worth seeking it out.
That's all the help I can be I'm afraid.

Anyone know the site name?[/quote

Hi Martin,

Thanks for your reaction. For you it is clear what the accronymes IIRC and SBF mean, but for me as a stranger to english I haven't a clue. So you have made me very curious. I like to hear from you what they stand for. Thanks in advance!

Best regards from Peter

garyv8tiger
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Post by garyv8tiger » Thu Aug 16, 2012 7:00 pm

sbf is small block ford .not sure if the other is someones name .hes a strange fella martin :mrgreen:

martin172
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Post by martin172 » Thu Aug 16, 2012 10:35 pm

pruyter wrote:
martin172 wrote:IIRC, a while back someone posted a link to a US site dedicted to SBF.

If you have no joy here, it could be worth seeking it out.
That's all the help I can be I'm afraid.

Anyone know the site name?[/quote

Hi Martin,

Thanks for your reaction. For you it is clear what the accronymes IIRC and SBF mean, but for me as a stranger to english I haven't a clue. So you have made me very curious. I like to hear from you what they stand for. Thanks in advance!

Best regards from Peter
Sorry Peter, they mean If I Remember Correctly and small block Ford.
I shouldn't abbreviate really, It's just me being lazy.

gtsmrt
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Post by gtsmrt » Fri Aug 17, 2012 7:44 am

Lucky we're not teenagers replying Peter or we would all have no hope... :)
Robin O'Dell
Tiger MK 1a
ENJOYING THE EXPERIENCE AS DAD WOULD HAVE

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