Emissions data
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Re: Emissions data
I had a look at the plugs, they are a healthy brown colour. mike said that as the cr was 12/1 so timing was retarded, I have not any information about jets but could the cr and timing account for the very lean mixture readings at idle. the petrol was v-power.
- fueltheburn
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Re: Emissions data
If nothing else has been altered....Compression ratio ... Yes. You are sqaushing 9% more air into the combustion stroke compared to the original HC engine at 11:1 CR
- Lotus-e-Clan
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Re: Emissions data
The CR and ignition timing per se will not determine what AFR is required for idle.alanbell wrote:I had a look at the plugs, they are a healthy brown colour. mike said that as the cr was 12/1 so timing was retarded, I have not any information about jets but could the cr and timing account for the very lean mixture readings at idle. the petrol was v-power.
However they would influence the optimum AFR for max torque for a specific engine (combustion chamber design & SCR /DCR etc will affect optimum ign timing required) - hence there is a normally accepted range of AFRs for best power and torque across a range of differnt engines - you have to find whats best for your spec.
For example my Clan engine has a SCR (static comp ratio) of 11.8 and likes 36 degrees BTDC ignition timing within the power rev range and goes like stink with an AFR of 13.2 within the power/torque rev range (5000 -9000 rpm).
This figure shows relationship between AFR and CO etc ...
This table clarifies AFR and CO% readings ....
From the table you can see it's your 3.2 CO% (AFR 13.3) that makes most sense IF that 's what you have in the max torque range....it's even OK as an idle figure, if a little rich (unnecessary waste of fuel).
A standard Excel SE with an IDLE AFR of 14.2- 14.3 (CO 0.5%) is perfectly achievable. And ideally this is what we should all aim to have come MOT time.
The AFR of 20+ makes no sense AT ALL as a useable setting (in any context!) it's completely off the scale!
Last edited by Lotus-e-Clan on Sat Mar 10, 2018 12:27, edited 1 time in total.
Peter K
- alanmoss
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Re: Emissions data
MOT passed today, no advisories. Emissions data CO 2.848% HC 200 ppm
The carburettors have not been adjusted for several years and like Angus I usually run on 95 ron.
The carburettors have not been adjusted for several years and like Angus I usually run on 95 ron.
Alan
Excel Celebration, 1999 Mini Cooper S, Dacia Duster 4x4
Excel Celebration, 1999 Mini Cooper S, Dacia Duster 4x4
- Jason.goad
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Re: Emissions data
Mine Passed it's m.o.t today. No advisories.
CO 3.58% HC 224 ppm.
CO 3.58% HC 224 ppm.
- amarshall
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Re: Emissions data
MOT Passed again. Emissions data : A little high this year
2.24% CO
1122 ppm HC
2.24% CO
1122 ppm HC
https://www.lotusexcel.co.uk/
SORN - just say NO!
SORN - just say NO!
- marky
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Re: Emissions data
Yes - passed again on Saturday.
CO2 0.482 - don't think it has reached 1% in any of the tests yet!
HC 210
no advisories
Car starting and running great.
Mark.
CO2 0.482 - don't think it has reached 1% in any of the tests yet!
HC 210
no advisories
Car starting and running great.
Mark.
- Jason.goad
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Re: Emissions data
Passed today. Gave it a bit of a carb tune before going
Co. 2.82%
HC 573 ppm
Co. 2.82%
HC 573 ppm
- shaunw
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Re: Emissions data
Passed the MOT today with no advisories and really good HC emissions results which have steadily improved year on year for the last 5 years, hopefully as a result of the hours of work on the carbs, ignition and vacuum pipes and not just a fluke due to the notorious inaccuracy of the testing machines.
HC 182
CO 2.15
Shaun
HC 182
CO 2.15
Shaun
- Lotus-e-Clan
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Re: Emissions data
Passed MOT today (after a brief fail for a rear bleed nipple not properly nipped D'oh! )
CO 0.51%
HC 822 (quite a warm day)
CO 0.51%
HC 822 (quite a warm day)
Peter K
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Re: Emissions data
Great news Peter. I look forward to seeing the motor out and about sometime.
Kev W no.282
- MrCoolA
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Re: Emissions data
as long as it's not a SundayKevW wrote:Great news Peter. I look forward to seeing the motor out and about sometime.
Previously Jerry (Taylor)
Now "Black Flag"
Lotus Excel SEI1989 253.6hp 190lbft
Lotus Elise S3 1.6. Motorsport Green 2011.
Now "Black Flag"
Lotus Excel SEI1989 253.6hp 190lbft
Lotus Elise S3 1.6. Motorsport Green 2011.
- Lotus-e-Clan
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Re: Emissions data
You never know...MrCoolA wrote:as long as it's not a SundayKevW wrote:Great news Peter. I look forward to seeing the motor out and about sometime.
Peter K
- amarshall
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Re: Emissions data
This year's figures:
CO: 2.93
HC: 64
Carbs were rebuilt last year as they were clogged with silt.
CO: 2.93
HC: 64
Carbs were rebuilt last year as they were clogged with silt.
https://www.lotusexcel.co.uk/
SORN - just say NO!
SORN - just say NO!
- marky
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Re: Emissions data
MOT pass this morning
emissions data ;-
CO = 0.724
HC = 107
Mark.
emissions data ;-
CO = 0.724
HC = 107
Mark.