Air fuel ratio readings on boost and rollers from SC?
18 July 2006, 12:07 PM
#32
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Hi,
its not piston nipping if you are running 4 thou clearance on race pistons, we allways map with a wide band lambda and finish on the road with det cans and the lap top pluged in, if its tinkling surley his knock link would be giving out warning signs.
Cheers
Kev.
its not piston nipping if you are running 4 thou clearance on race pistons, we allways map with a wide band lambda and finish on the road with det cans and the lap top pluged in, if its tinkling surley his knock link would be giving out warning signs.
Cheers
Kev.
18 July 2006, 12:23 PM
#33
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think you need to post up the graph rather than just say this and that, by not just seem like your shouting without backing up what you say and could be seen as perhaps not being completely true.
18 July 2006, 12:23 PM
#34
Swisstonihasher : Do you have "4 thou clearance on race pistons" and race valves???
Kev : Trust me. At EGTs of 935 C you are in the area where pistons melt and valves fail.
As you did not map the car, I am not critising your mapping. Maybe you have missunderstood but with high EGTs valve failure is round the corner and standard valves fail before a sustained 930 C.
Kev : Trust me. At EGTs of 935 C you are in the area where pistons melt and valves fail.
As you did not map the car, I am not critising your mapping. Maybe you have missunderstood but with high EGTs valve failure is round the corner and standard valves fail before a sustained 930 C.
Last edited by harvey; 18 July 2006 at 12:31 PM.
18 July 2006, 12:43 PM
#35
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Hi harvey,
I have been told that under grief the egt went up to 900 and under serious grief it once hit 915 degrees, I agree its not long before valves will melt at 935 if you keep your toe in, but thats why we have gauges they tell us when to back off, if we care to take notice.
My mapper is quite happy with 900 degrees and says that for very very short spells 950 degrees.
I have asked the owner to take a steady drive down and we can re-run it on the dyno overlaying the graphs to see if it has actually leaned off, we await his response.
Cheers
Kev.
I have been told that under grief the egt went up to 900 and under serious grief it once hit 915 degrees, I agree its not long before valves will melt at 935 if you keep your toe in, but thats why we have gauges they tell us when to back off, if we care to take notice.
My mapper is quite happy with 900 degrees and says that for very very short spells 950 degrees.
I have asked the owner to take a steady drive down and we can re-run it on the dyno overlaying the graphs to see if it has actually leaned off, we await his response.
Cheers
Kev.
18 July 2006, 01:15 PM
#38
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You should post the graph mate 
Not at SC, but on a dyno dynamics RR at G force motorsport.
http://img.photobucket.com/albums/v3...ark/graph1.jpg
Not at SC, but on a dyno dynamics RR at G force motorsport.
http://img.photobucket.com/albums/v3...ark/graph1.jpg
18 July 2006, 01:16 PM
#39
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I will post the roller sheets tomorrow now Kev, or earliest tonight (as scanned images at home)
Thanks Harvey, I've decided to halt driving
it till I get it checked out at a later date. Re 4 thou clearance and race valves - no idea but std heads, modified slightly with oe WRX 02 valves and CP pistons
This is not what I wanted to happen, being all public and disagreements...
Thanks Harvey, I've decided to halt driving
it till I get it checked out at a later date. Re 4 thou clearance and race valves - no idea but std heads, modified slightly with oe WRX 02 valves and CP pistonsThis is not what I wanted to happen, being all public and disagreements...
Last edited by swisstonihasher; 18 July 2006 at 01:22 PM.
18 July 2006, 01:36 PM
#40
Kev : Please do not missunderstand. I have not critisised Scooby Clinic in any way.
As I understand it, you did not map the car but did some power runs showing AFRs which now unsettle the owner.
I have already pointed out that in some cases it is possible to have different on road to rolling road AFRs for a number of reasons on MAF Sensor equiped cars. On road AFRs are required.
The owner then posted
935 C is his figure. I have no idea what pistons or valves he has but that temperature for any length of time does destroy valves and pistons. Combined with his AFR concern, this should be very worrying to anybody that wants to preserve their engine.
Having run in the past at up to 930C, I now consider 900C as around the top limit.
When my car is mapped I do not want to have to keep looking at the EGT to ensure everything is OK. On full power there is a lot going on and head in the cabin is sometimes inadvisable. If I do not look at a critical time I might miss the 950 C and loose an engine.
How long is very, very short?
I assume you are not referring to Subaru pistons and valves.
As I understand it, you did not map the car but did some power runs showing AFRs which now unsettle the owner.
I have already pointed out that in some cases it is possible to have different on road to rolling road AFRs for a number of reasons on MAF Sensor equiped cars. On road AFRs are required.
The owner then posted
It's the EGT temps of max 918 to 935 deg that started me off with worries re setup - car def lean and will get it resolved once funding available .
Having run in the past at up to 930C, I now consider 900C as around the top limit.
My mapper is quite happy with 900 degrees and says that for very very short spells 950 degrees.
How long is very, very short?
I assume you are not referring to Subaru pistons and valves.
18 July 2006, 01:56 PM
#42
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Thanks Harvey...but to be honest if I can boot the car and smile, no point driving her
. I'm not happy with the EGT's being that high on std valves and, like you said, I've got enough on my plate controlling the car let alone watching the EGT and knock link every 5 seconds (although I do have an EGT warning light, now set to 890 deg, which goes off all the time).
Will resolve this soon, plus post roller graphs.
. I'm not happy with the EGT's being that high on std valves and, like you said, I've got enough on my plate controlling the car let alone watching the EGT and knock link every 5 seconds (although I do have an EGT warning light, now set to 890 deg, which goes off all the time).Will resolve this soon, plus post roller graphs.
18 July 2006, 02:46 PM
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Yeh m8 and its got more potential. The excellent people at Quick Motorsport, Hereford - the only true place I'd trust with anything. They're tops, quality of work is 2nd to none.
18 July 2006, 02:48 PM
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Hi,
no missunderstandings harvey, and thanks for your input.
However here are my power graphs, this car runs almost the same spec as Swisstonihasher, is in daily use, has covered over 7000 miles and gets some serious grief as it is also the scoobyclinic demo car, so far no melted pistons (tempt fate, why not) 2 sets of rear tyres though!
Cheers
Kev.
no missunderstandings harvey, and thanks for your input.
However here are my power graphs, this car runs almost the same spec as Swisstonihasher, is in daily use, has covered over 7000 miles and gets some serious grief as it is also the scoobyclinic demo car, so far no melted pistons (tempt fate, why not) 2 sets of rear tyres though!
Cheers
Kev.
18 July 2006, 02:59 PM
#49
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Kev, seeing your graph does confirm mine's leaner than yours (not by alot) all the way upto 6000 rpm. Will post graphs tonight (once I'm back from a works party and if I can figure how to switch pc on by then!).
Also, any idea of your EGTs?
Also, any idea of your EGTs?
19 July 2006, 09:59 AM
#50
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Having a brain fart 
moment here people - how do you paste jpegs to the website as cut and paste doesn't work (prob to prevent pervs putting crap on the site I'm sure).
moment here people - how do you paste jpegs to the website as cut and paste doesn't work (prob to prevent pervs putting crap on the site I'm sure).
from last night.
19 July 2006, 12:09 PM
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Oh and just to confirm with all, Pat did map at Scoobyclinic using their rollers. She's running std ecu ecutek with no boost controller (just 2 port solenoid) at present.
19 July 2006, 12:11 PM
#59
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Just a "quick" note... 
I'll admit to being "guilty" of mapping the car
But it looks like things are being taken out of some proportion and context...
Re: rough running and CEL, what Tony has neglected to mention, or at least place sufficient emphasis on is the fact that the cams are pretty wild, so much so that it's not possible to achieve a "normal" idle and even with a raised idle an occasional missfire is the order of the day. Other than that, running an FMIC with a MAF is a recipe for "artefacts", the rich spike on the graph, for example, is a "pressurisation spike" where the MAF sees air going into the turbo but it's not going into the engine, it's pressurising the FMIC pipework. Such artefacts are unavoidable on a MAF based system, and they do detract from the driving experience, but that's a function of customer choice not to use and speed density system (as I would always recommend on an FMIC car) which is immune to these foibles.
Regards AFR, you cannot make a simple blanket statement about what AFR is "right". Mostly the engine will dictate what is and what isn't acceptable, and let's not forget that what we are seeing is the appearance AFR, not the actual AFR. For those that don't understand the difference, please take the time to educate yourselves before passing judgement on something you clearly do not understand.
I think Harvey has been somewhat unlucky to have had an issue with 930 degrees EGT, it's actually quite cool in the great scheme of things. I would normally recommend that people don't run over 950 degrees EGT for longevity reasons, but it's certainly not a problem to run more. I got over 60,000 miles out of my own car running around 950 degrees, again with standard UK valves. The only reason the the engine was removed was that it had already done about 60k when I got it, and at 120,000 miles it wanted freshening up. The turbo went in for a refurb but it was pristine despite running ALS on track.
As Kev has already indicated, we're more than happy to look at and adjust the car again if Tony is unhappy with the current setup. I'll happily set it up to run 11.0:1 appearance AFR to keep the keyboard heroes happy, but of course in the real world that will cost performance and fuel for no tangible benefit.
Best regards,
Pat.
I'll admit to being "guilty" of mapping the car
But it looks like things are being taken out of some proportion and context...Re: rough running and CEL, what Tony has neglected to mention, or at least place sufficient emphasis on is the fact that the cams are pretty wild, so much so that it's not possible to achieve a "normal" idle and even with a raised idle an occasional missfire is the order of the day. Other than that, running an FMIC with a MAF is a recipe for "artefacts", the rich spike on the graph, for example, is a "pressurisation spike" where the MAF sees air going into the turbo but it's not going into the engine, it's pressurising the FMIC pipework. Such artefacts are unavoidable on a MAF based system, and they do detract from the driving experience, but that's a function of customer choice not to use and speed density system (as I would always recommend on an FMIC car) which is immune to these foibles.
Regards AFR, you cannot make a simple blanket statement about what AFR is "right". Mostly the engine will dictate what is and what isn't acceptable, and let's not forget that what we are seeing is the appearance AFR, not the actual AFR. For those that don't understand the difference, please take the time to educate yourselves before passing judgement on something you clearly do not understand.
I think Harvey has been somewhat unlucky to have had an issue with 930 degrees EGT, it's actually quite cool in the great scheme of things. I would normally recommend that people don't run over 950 degrees EGT for longevity reasons, but it's certainly not a problem to run more. I got over 60,000 miles out of my own car running around 950 degrees, again with standard UK valves. The only reason the the engine was removed was that it had already done about 60k when I got it, and at 120,000 miles it wanted freshening up. The turbo went in for a refurb but it was pristine despite running ALS on track.
As Kev has already indicated, we're more than happy to look at and adjust the car again if Tony is unhappy with the current setup. I'll happily set it up to run 11.0:1 appearance AFR to keep the keyboard heroes happy, but of course in the real world that will cost performance and fuel for no tangible benefit.
Best regards,
Pat.