TiT or ToT.?
11-29-2005, 09:30 PM
#16
HAHAH
No idle stabilizer - and not even run without it one time and fuel tuned, plus 20 degrees F - that's why it stalled.
Campec - if I spent the time to get the injectors suited and then got the semi-sequential pairs in synch - I could balance them absolutely perfectly. But its not worth it - they are really not off by anything at all significant.
No idle stabilizer - and not even run without it one time and fuel tuned, plus 20 degrees F - that's why it stalled.
Campec - if I spent the time to get the injectors suited and then got the semi-sequential pairs in synch - I could balance them absolutely perfectly. But its not worth it - they are really not off by anything at all significant.
11-30-2005, 02:57 AM
#18
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Originally Posted by special tool
Also - being the nutjob that I am - I am sure you guys know that I have shuffled the injectors and the plugs to varify.....TWICE. 
11-30-2005, 02:58 AM
#19
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Since I did not hear any horror stories about EGT breaking off and causing problems, i think i will NOT go with the TOT. Instead, it sounds like cyl. #2 would be a good bet. Thanks Bill and ST.
11-30-2005, 08:03 AM
#20
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This is great info! IT's always been excepted that #4 was the hottest. I've also read that the stock manifold was a poor design hence the need to up grade.
This info actually shows that the manifold was designed well and there is no need to upgrade , unless one wants more flow.
Ground braking info , thanks.
This info actually shows that the manifold was designed well and there is no need to upgrade , unless one wants more flow.
Ground braking info , thanks.
11-30-2005, 09:22 AM
#21
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I have been running a 4 channel set up for the last three years – 1 and 4 are pretty even and 2 and 3 are typically about 50 degrees hotter.
Running a 12 to 12.5 to 1 AFR I see 1650 at the track with peaks up to 1700. Changing timing and fuel ratios does not have a ‘great’ effect on this. To get the EGT to decrease noticeably (100 degrees) can not be accomplished with timing and AFR changes.
The hottest recorded temps are about ½ way onto the warm up cycle – rich mixture and small throttle openings. Remember that you are reading the temps in the exhaust port – if the timing is retarded and the mixture is rich the fuel will still be burning in the exhaust manifold so you will see high EGTs – this does not reflect on the actual temps in the cylinder head.
It doesn’t really matter what cylinder you pick – what you are looking for is changes in EGT from mods to your set up – all cylinder will have the same delta in EGT due to tuning changes. Unless you are modifying the intake manifold then I would just use the cylinder that is easiest to access (typically #4).
Chris White
Running a 12 to 12.5 to 1 AFR I see 1650 at the track with peaks up to 1700. Changing timing and fuel ratios does not have a ‘great’ effect on this. To get the EGT to decrease noticeably (100 degrees) can not be accomplished with timing and AFR changes.
The hottest recorded temps are about ½ way onto the warm up cycle – rich mixture and small throttle openings. Remember that you are reading the temps in the exhaust port – if the timing is retarded and the mixture is rich the fuel will still be burning in the exhaust manifold so you will see high EGTs – this does not reflect on the actual temps in the cylinder head.
It doesn’t really matter what cylinder you pick – what you are looking for is changes in EGT from mods to your set up – all cylinder will have the same delta in EGT due to tuning changes. Unless you are modifying the intake manifold then I would just use the cylinder that is easiest to access (typically #4).
Chris White
11-30-2005, 11:51 AM
#22
Great..
5 min ago I was holding the exhaust Headers in my hand ready to drill a hole for a EGT probe in nr4# .. Just needed a coffee and check my e- mail first..
nr 2# it is then
Btw: somebody got a link to the aviation EGT thing ST has, or similar??
5 min ago I was holding the exhaust Headers in my hand ready to drill a hole for a EGT probe in nr4# .. Just needed a coffee and check my e- mail first..
nr 2# it is then
Btw: somebody got a link to the aviation EGT thing ST has, or similar??
11-30-2005, 04:42 PM
#24
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Someone must know why the head gasket fails on #4?
My head gasket has just gone, and i would like to know why, is it a weakness, or are my guru chips not the best for mixture and timing?
My head gasket has just gone, and i would like to know why, is it a weakness, or are my guru chips not the best for mixture and timing?
11-30-2005, 05:07 PM
#25
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Originally Posted by Tomas L
If #4 is not the leanest cylinder then why does the head gasket most frequently fail in that cylinder?
Coolant flow?
Weakness in the block/head?
Coolant flow?
Weakness in the block/head?
Many theories but no real answers.
BTW – its always the same point on the head gasket that lets go (not just the same cylinder).
Chris White
11-30-2005, 10:03 PM
#26
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Originally Posted by Trucho-951
I want to add an EGT probe to my street car and was wondering if folks here have ever experienced damage to the turbo from a deteriorating EGT probe placed upstream of the turbo, i.e. one that measures the turbo inlet temp. (TIT). I had read somewhere that if the thermocouple tip breaks off, it could damage the turbine.
To be on the safe side, I was thinking of placing it downstream, i.e, measuring the turbo outlet temp (TOT) but am not sure if placing the EGT that far from the engine still provides useful info.
To be on the safe side, I was thinking of placing it downstream, i.e, measuring the turbo outlet temp (TOT) but am not sure if placing the EGT that far from the engine still provides useful info.
11-30-2005, 11:22 PM
#27
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12-01-2005, 12:59 AM
#28
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There are different types of EGT’s, some are closed (stainless steel tube) and some have exposed thermocouple. The closed type has slower response time, but is more rugged/durable than the open type. I just completed installation of 6 selectable EGT’s (bought here ), 4 for the exhaust (closed style) and 2 for the intake (open style) and my very first measurements at idle seem to confirm ST’s and Chris’ observations.
Reg. headgasket: Only cylinder #4 has relative large triangular shaped water passages close to the “fire ring”. With high combustion pressure, marginal clamping force and rusting of the corrugated metal in the center layer of the standard HG the fire ring tend to be pushed oval and sometimes too oval as in the picture.
Laust
Reg. headgasket: Only cylinder #4 has relative large triangular shaped water passages close to the “fire ring”. With high combustion pressure, marginal clamping force and rusting of the corrugated metal in the center layer of the standard HG the fire ring tend to be pushed oval and sometimes too oval as in the picture.
Laust
Last edited by Laust Pedersen; 01-14-2013 at 03:33 PM.
12-01-2005, 02:32 AM
#29
Formula One Spin Doctor
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Originally Posted by Chris White
I have been running a 4 channel set up for the last three years – 1 and 4 are pretty even and 2 and 3 are typically about 50 degrees hotter.
Running a 12 to 12.5 to 1 AFR I see 1650 at the track with peaks up to 1700. Changing timing and fuel ratios does not have a ‘great’ effect on this. To get the EGT to decrease noticeably (100 degrees) can not be accomplished with timing and AFR changes.
The hottest recorded temps are about ½ way onto the warm up cycle – rich mixture and small throttle openings. Remember that you are reading the temps in the exhaust port – if the timing is retarded and the mixture is rich the fuel will still be burning in the exhaust manifold so you will see high EGTs – this does not reflect on the actual temps in the cylinder head.
It doesn’t really matter what cylinder you pick – what you are looking for is changes in EGT from mods to your set up – all cylinder will have the same delta in EGT due to tuning changes. Unless you are modifying the intake manifold then I would just use the cylinder that is easiest to access (typically #4).
Chris White
Running a 12 to 12.5 to 1 AFR I see 1650 at the track with peaks up to 1700. Changing timing and fuel ratios does not have a ‘great’ effect on this. To get the EGT to decrease noticeably (100 degrees) can not be accomplished with timing and AFR changes.
The hottest recorded temps are about ½ way onto the warm up cycle – rich mixture and small throttle openings. Remember that you are reading the temps in the exhaust port – if the timing is retarded and the mixture is rich the fuel will still be burning in the exhaust manifold so you will see high EGTs – this does not reflect on the actual temps in the cylinder head.
It doesn’t really matter what cylinder you pick – what you are looking for is changes in EGT from mods to your set up – all cylinder will have the same delta in EGT due to tuning changes. Unless you are modifying the intake manifold then I would just use the cylinder that is easiest to access (typically #4).
Chris White
Hello All,
Have to be very careful here with all this , chris i believe your egt probes are impropely installed, and is giving you heat soaked readings instead of a true EGT reading .
your engine will not last at 1700 and at the very least you would have lost your Turbine by now.
Installation of the probe into the tubular header is very critical as to the installed height and this is why you are not seeing any changes when you move the timing. 3 degress either way will move that EGT my friend very rapidly under load.
Having probes in each cylinder is not uncommon and used mainly when adjusting engines on the dyno in full sequential mode, as this is the only true way to adjust each cylinder based on A/F and EGT.
The highest EGT when all is adjusted correctly will take place at max piston speed , hence you will see more heat at 9000 rpm wide open than at 6000 rpm wide open. So appropriate measures has to be taken to have the egt remain safe after peaking @6000 rpm so as not to be "off the scale"@9000 rpm, If you are seeing high egt's at partial load low rpm your mapping is incorrect.
12-01-2005, 02:39 AM
#30
Formula One Spin Doctor
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Originally Posted by ross255
Someone must know why the head gasket fails on #4?
My head gasket has just gone, and i would like to know why, is it a weakness, or are my guru chips not the best for mixture and timing?
My head gasket has just gone, and i would like to know why, is it a weakness, or are my guru chips not the best for mixture and timing?
Careful mapping of the engine paying attention to this will solve the problem.
for those who are not in the position to do so, put a plug 2 heat ranges colder than the rest. Your guru chips might also be too aggressive for your setup.
PS. Laust , Love the Lambos , wanted an espada for a long time ( going back 25 years) , wow you really have both ? very rare cars !