Exhaust gas temperatures
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Le Mans Master
Joined: Apr 2000
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From: New York New York
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Exhaust gas temperatures
A friend of mine has a 70 LT-1. When he checks his exhaust manifolds with an IR gun, he reads 600 degrees. I think this is high.
He has spark knock that he is trying to find the cause.
Compression is around 240 PSI, which I also think it is high, the gauge is accurate, I used it on my car and got 150.
The timing is set at 38 total without the vacuum advance.
Any ideas?
He has spark knock that he is trying to find the cause.
Compression is around 240 PSI, which I also think it is high, the gauge is accurate, I used it on my car and got 150.
The timing is set at 38 total without the vacuum advance.
Any ideas?
Intermediate
Joined: Mar 1999
Posts: 48
Likes: 0
From: cohasset mn usa
Re: Exhaust gas temperatures (redvetracr)
Hey Redvetracr, Why did You pick that cyl over the rest? I seen places that use # 1 instead. What I understand is We should watch the leanest cyl and adjust to that.But then again how do we tell without haveing a probe in each one? :chevy
Race Director
Joined: Aug 1999
Posts: 18,126
Likes: 174
From: WI
Re: Exhaust gas temperatures (philo)
philo, As in all things, you ask a question and (in this case) I got 8 answers. #7 was easy and i could hit a straight spot in the spaghetti (headers). I just shoot for a temperature range BUT I also read the plugs and in the case of the last race I changed jets three times during the weekend (I also changed the timing). It all paid off as I won the race. ...redvetracr
Le Mans Master
Joined: Feb 1999
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From: Hoosier
Cruise-In III Veteran
Re: Exhaust gas temperatures (plaidside)
Just a thought. Those IR guns have to be callabrated to the surface they're pointed at. Exanple..a coated header reflects differently than a cast iron header and the heat readings will vary considerably.
Race Director
Joined: Jun 2001
Posts: 16,483
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From: The Only Corvette in Gila Bend, Az.
St. Jude Donor '09
Re: Exhaust gas temperatures (AlwaysWave)
On my 93 F350 with a fuel injected 460 the temps exceed 1750 degrees...as tested by Banks with a stock motor... and mine is no longer stock.... :D
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From: Reno Nevada
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Re: Exhaust gas temperatures (norvalwilhelm)
I've seen glowing headers and that must be around 12-1300. I had thermoTec header wrap on and melted the pimary pipes
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From: The Only Corvette in Gila Bend, Az.
St. Jude Donor '09
Re: Exhaust gas temperatures (norvalwilhelm)
How do you keep valves in a motor at 1750 degrees? 1400 is getting dangerous.
All I can say is that Ford put it out this way, and the big block fords with fuel injection are well known for warping the cast exhaust manifolds.
The only real replacement was to go with Banks high tensile stainless steel.
The factory manifolds were over $800.00 for just one side. And I was warping them about one every other year.
I paid over $1,700.00 for the Banks setup, and have not had any problems for the last 5 years...
[Modified by Desertdawg, 5:19 PM 11/26/2002]