[Land-speed] EGT

[Dave Dahlgren]

What is the lobe separation is the real number I am after do plugs look like 
it is a happy engine? I have run some pretty good overlap in a SC engine 
that would be too much for a turbo. 107 to 108 lobe centers with an intake 
centerline of 110 is pretty common. The idea is to blow a little fresh air 
over the piston to cool it down and screw the fuel consumption or brake 
specific readings this is not a mileage test..LOL The charge air cooling is 
a good idea on two fronts.. first it will make more power with less boost 
second it will lower the intake air temps a ton which will lower the egt as 
well. Right now I would bet the intake air temps are well over 300 possibly 
close to 400. If you drop the intake air temp 200 degrees the egt goes down 
with them.  as you suggest the O2 sensor readings are probably not worth 
worrying about just read the plugs.
Dave
----- Original Message ----- 
From: "Skip Higginbotham" <saltrat at pahrump.com>
To: "Dave Dahlgren" <ddahlgren at snet.net>; "Adin, David" 
<DavidAdin at mercydurango.org>
Cc: <land-speed at autox.team.net>
Sent: Tuesday, September 30, 2008 12:04 PM
Subject: Re: [Land-speed] EGT


> Hi Dave,
> Cam timing is 322 duration split, ignition timing is 30 degrees locked, 
> a/f ratios are not accurate (according to gage engineering) due to short 
> stacks, 12", and sensor about 4" from valve (1 cyl).....but it read .5 to 
> .6 volts at power and RPM until the rockers both broke on that cyl.
> Skip
>
>
>
>
> At 08:33 AM 9/30/2008, Dave Dahlgren wrote:
>>tell me about the cam timing and ignition timing a/f ratios if you have 
>>them..
>>Dave
>>----- Original Message ----- From: "Skip Higginbotham" 
>><saltrat at pahrump.com>
>>To: "Adin, David" <DavidAdin at mercydurango.org>
>>Cc: <land-speed at autox.team.net>
>>Sent: Tuesday, September 30, 2008 11:06 AM
>>Subject: Re: [Land-speed] EGT
>>
>>
>>>David,
>>>Are you running a turbo?
>>>Skip
>>>
>>>
>>>
>>>At 07:59 AM 9/30/2008, Adin, David wrote:
>>>>Hi Skip,
>>>>
>>>>FWIW: 1600cc Miata, 22lbs boost EGT = ~1800.  My a/f was right on.
>>>>
>>>>What I noticed was how long the temp stayed up there, keeping in mind I
>>>>had never been in the boost for two miles on the street.
>>>>
>>>>My guess (and purely a SWAG) is:  good a/f with this egt is ok.
>>>>
>>>>I'd ask Dahlgren . . .
>>>>
>>>>Regards,
>>>>
>>>>David in Durango