DIY Modification to Improve Performance and Fuel Economy of AJ16 and AJ6 Engines
#261
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I've just taken delivery of the latest batch of brackets. This takes the total production to 300. If anyone wants one, then please email me direct at andystodart@metronet.co.uk
#262
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So I have been reading lately a lot of people using K&N air filters, heat shields and positioning of the air intake to jam in more air. Today I discovered a post by XJRengineer from 2012 where he was giving reasons where you would want to reprogram your ECU. One of the reasons was:
"modifications to the engine that would increase the airflow by more than about 10% resulting in under-reading of the airflow by the saturated air meter and excessive enleanment of the fueling"
That raises the question if everybody is stuffing more air into the engine are they at risk of overdoing it? If people are using high-flow air filters and some sort of "ram air" are they at risk of doing something to force the long term fuel trim to make major adjustments? How much can we improve air intake before we over do it and how much extra air intake do we really need?
"modifications to the engine that would increase the airflow by more than about 10% resulting in under-reading of the airflow by the saturated air meter and excessive enleanment of the fueling"
That raises the question if everybody is stuffing more air into the engine are they at risk of overdoing it? If people are using high-flow air filters and some sort of "ram air" are they at risk of doing something to force the long term fuel trim to make major adjustments? How much can we improve air intake before we over do it and how much extra air intake do we really need?
#263
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#264
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#266
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I have recently manufactured my 300th crankshaft bracket, which I think is quite a milestone for this simple modification. Thank you very much to everyone who has shown their confidence in the idea and fitted one of these parts. I hope to continue to offer this part as long as there is demand.
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#267
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I just exchanged email with Andy, and he has suspended making his brackets and has no current plans to resume making them as it became too much effort to keep up with demand. I asked him for permission to add that status to this thread.
So if anyone has a bracket they never used, a spare, or were retiring a car with a bracket they were willing to part with, please let me know.
Andy is keeping a list of those that have inquired into the bracket, but at this time is not making any more.
Thanks to Andy for his expertise and the brackets he made so far! Here's hoping he'll find the time again to put them in production again
So if anyone has a bracket they never used, a spare, or were retiring a car with a bracket they were willing to part with, please let me know.
Andy is keeping a list of those that have inquired into the bracket, but at this time is not making any more.
Thanks to Andy for his expertise and the brackets he made so far! Here's hoping he'll find the time again to put them in production again
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Last edited by al_roethlisberger; 05-12-2014 at 08:35 PM.
#268
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Al,
Thank you for making us aware of Andy's decision. I'm sure none of us can fully appreciate all the time and effort that has been involved in making the brackets available.
Andy,
On behalf of all of us who have enjoyed the benefits of your timing advance bracket, I regret that others may not be able to enjoy the same. Between the livelier mid-range engine response and the significant increase in fuel economy, I'll never take your bracket off of our '93 XJ40!
Yours in appreciation,
Don
Last edited by Don B; 05-12-2014 at 10:43 PM.
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#270
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Al,
Thank you for making us aware of Andy's decision. I'm sure none of us can fully appreciate all the time and effort that has been involved in making the brackets available.
Andy,
On behalf of all of us who have enjoyed the benefits of your timing advance bracket, I regret that others may not be able to enjoy the same. Between the livelier mid-range engine response and the significant increase in fuel economy, I'll never take your bracket off of our '93 XJ40!
Yours in appreciation,
Don
Thank you for making us aware of Andy's decision. I'm sure none of us can fully appreciate all the time and effort that has been involved in making the brackets available.
Andy,
On behalf of all of us who have enjoyed the benefits of your timing advance bracket, I regret that others may not be able to enjoy the same. Between the livelier mid-range engine response and the significant increase in fuel economy, I'll never take your bracket off of our '93 XJ40!
Yours in appreciation,
Don
That increased mileage would be a huge boon on my 120 mile per day commute
![Wink](https://www.jaguarforums.com/forum/images/smilies/wink.gif)
In the meantime I've placed a "WTB" ad in the Marketplace to see if anyone has a spare they bought but never used, etc and would like to sell it.
Last edited by al_roethlisberger; 05-13-2014 at 05:29 PM.
#271
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The bracket is doing ok, from 12.5lt/100Km became 11.7lt/100Km, I watch it the last 5 months, all kind of driving type averages.
what is this stainless steel shield at the photos, above the filter element supposed to do?
what advantages will give colder air at the intake..?
how much colder?
Since the thread is for the bracket, the bracket is ok on the economy side, on the performance side I have no view/opinion
what is this stainless steel shield at the photos, above the filter element supposed to do?
what advantages will give colder air at the intake..?
how much colder?
Since the thread is for the bracket, the bracket is ok on the economy side, on the performance side I have no view/opinion
#272
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Sounds like you're referring to the heat shield in my posts #223 & 224?
I described its purpose as best I could in those posts (note: it is made from aluminium sheet, not SS).
Basically it helps to shield the filter pod from engine heat, instead concentrating cold air flow from behind the head lights and fender cavity. Several posts in this thread (and others) discuss the benefits of cold air induction. The side panel on the shield helps to protect the pod from water splashing up underneath.
As to whether a shield is necessary is a matter of opinion, but I feel it can only do good and no harm.
I described its purpose as best I could in those posts (note: it is made from aluminium sheet, not SS).
Basically it helps to shield the filter pod from engine heat, instead concentrating cold air flow from behind the head lights and fender cavity. Several posts in this thread (and others) discuss the benefits of cold air induction. The side panel on the shield helps to protect the pod from water splashing up underneath.
As to whether a shield is necessary is a matter of opinion, but I feel it can only do good and no harm.
#273
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Dear All,
Due to the continuing demand, I have decided to restart production of my revised crank sensor brackets for AJ16 engines. My wife will be processing any enquiries and orders for brackets on my behalf at her email address helenstodart@gmail.com . However, she will not be able to answer any technical question. For that I would refer you my original thread.
DIY Modification to Improve Performance and Fuel Economy of AJ16 and AJ6 Engines
There are couple of questions that I am regularly asked about these brackets, which I shall endeavour to answer below
1. It is not necessary to use a higher octane fuel than 95RON (approx. 90 pump octane / 90 anti-knock index (AKI))
2. the bracket will also fit AJ6 engines fitted to XJ40 after VIN 667829 and XJS vehicles after VIN 179737
Thank you to everyone for your continued interest in these brackets.
Due to the continuing demand, I have decided to restart production of my revised crank sensor brackets for AJ16 engines. My wife will be processing any enquiries and orders for brackets on my behalf at her email address helenstodart@gmail.com . However, she will not be able to answer any technical question. For that I would refer you my original thread.
DIY Modification to Improve Performance and Fuel Economy of AJ16 and AJ6 Engines
There are couple of questions that I am regularly asked about these brackets, which I shall endeavour to answer below
1. It is not necessary to use a higher octane fuel than 95RON (approx. 90 pump octane / 90 anti-knock index (AKI))
2. the bracket will also fit AJ6 engines fitted to XJ40 after VIN 667829 and XJS vehicles after VIN 179737
Thank you to everyone for your continued interest in these brackets.
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#274
#275
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Dear All,
There are still a few brackets left from the most recent batch that I have had manufactured, if anyone wants one. If so, please contact helenstodart@gmail.com
I have recently discovered that it is not possible to simply define which XJS engines my brackets will fit by the VIN number. In addition to the VIN number needing to be greater than 179737, the engine number must also exceed 161587. I hope this clarifies the position for any XJS owners wanting a bracket.
There are still a few brackets left from the most recent batch that I have had manufactured, if anyone wants one. If so, please contact helenstodart@gmail.com
I have recently discovered that it is not possible to simply define which XJS engines my brackets will fit by the VIN number. In addition to the VIN number needing to be greater than 179737, the engine number must also exceed 161587. I hope this clarifies the position for any XJS owners wanting a bracket.
#277
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....the distributor micrometer adjustment for optimizing timing advance ...O for simpler days! Only been the proud owner of Carson, a 1997 VDP for three weeks and I've been devouring these excellent forums ...
But I did panic when I read that Andy's Famous Bracket was to be no more .....but then thrilled to discover production had been restarted ...so I mailed today and hope I'm not too late!
Just one question about placing what amounts to a permanent 5 degree increase in static advance .....I'm wondering about the effect this has during starting and whether it could make for hard starting? I've noticed that my X300 does crank more than I'm used to before the engine fires ....nothing too excessive, but noticeable.
I'm guessing that the ECM must normally retard the timing briefly during starting so perhaps this is not a concern?
But I did panic when I read that Andy's Famous Bracket was to be no more .....but then thrilled to discover production had been restarted ...so I mailed today and hope I'm not too late!
Just one question about placing what amounts to a permanent 5 degree increase in static advance .....I'm wondering about the effect this has during starting and whether it could make for hard starting? I've noticed that my X300 does crank more than I'm used to before the engine fires ....nothing too excessive, but noticeable.
I'm guessing that the ECM must normally retard the timing briefly during starting so perhaps this is not a concern?
#279
#280
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I noticed Zero difference in crank times before/after installation. But then, mine has always been something of an "instant starter" - Fortunately, I've never even had time to notice if I get revs during cranking on the rev-counter....lemme find some burled elm to knock on....