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Drag Racing Discussions => Electronics => Topic started by: gregm784 on December 12, 2019, 02:31:33 PM

Title: EGT port location preference?
Post by: gregm784 on December 12, 2019, 02:31:33 PM
I'm adding EGTs to the dragster. Is there a preference on EGT location? Short side of radius? long side of radius (aka top or bottom of zoomies)? How far from port or exh valve?
Title: Re: EGT port location preference?
Post by: wideopen231 on December 13, 2019, 03:27:21 AM
When building a set of zoomies and customer wants EGT.  I like bottom and about 4" out if possible. The furthure out you move them the lower the  temp will be at any point,in other words. If you normally have 1050 target temps and you move EGT 2" you will probably be burning pistons around 1000*,just example. If you have data from another setup put them as close to same distance as possible,if not then its where you like them. As for bottom I have been told some data recorder company's want them on top.IMO if you have probe center of pipe it should not matter.
Title: Re: EGT port location preference?
Post by: gregm784 on June 02, 2020, 11:02:31 PM
Finally warmed the car up with EGTs....

Idling temps are 150-200 for #1 & #2.  Rest are around 1000*

Numbers in picture are holding the RPM at 3500 for about 4 seconds. 

My thoughts are it is pretty fat on the barrel valve and burning the fuel in the pipes.  30* in the mag, 387" SBC, 671 on alcohol.
Title: Re: EGT port location preference?
Post by: wideopen231 on June 27, 2020, 06:16:19 AM
I would agree with urning fuel in pipes. Not all cars run same temps abd location is part of it.  My Top alcohol setup where  650 stage at 6500 and 1050 or less at finish line. At 1100 car needed bearing checked probably flattened few thou.At 1150 It probably needed a new piston in the hole. AGain not all are same. Plugs and bearings will talk to you if you listen to them. EGT are great for tuning if used correctly and best for keeping track of tune.
Title: Re: EGT port location preference?
Post by: gregm784 on July 07, 2020, 11:32:13 AM
We've now got one race (5 laps) on the data recorder.  EGTs are fun to watch.  nice even readings, minus the front two, which are expectedly cooler (hat nozzles only, roots blower pushing fuel forward)
Title: Re: EGT port location preference?
Post by: jeff/21 on July 07, 2020, 05:11:06 PM
I moved injectors around and were of different sizes 406 brodix heads 6-71 littlefield and all cylinders were close at 2500 didn't make any difference in the 1/4