EGT/BOOST Gauge

[FD5]

Thinking about getting gauges but I have a few questions first:



1. What is the purpose of the boost gauge (Can you mechanically tear up a truck without the gauge or does it just make your truck look COOL)?



2. What is melted down without the knowing the EGT's (Heads, turbo charger, exhaust manifold)?



3. Should the sending unit for the EGT gauge be mounted before or after the turbo charger?



4. Gauge I am looking at has a weld in sending unit. Should I stay away from this and go with a thread in sending unit?



Maybe this info will help out others as well as myself.



John Hatch

 

[LSMITH]

John, I will answer the questions that I can for you.



1. the boost guage will tell you if you have a boost leak that is causing high EGT. It will also tell you how hard you are pulling, and can be a determining factor in shifting. You can pull one of these engines down on a grade to the point where EGT keeps climbing and boost starts to drop, if boost starts to drop and you are at full throttle DOWNSHIFT. It will also tell you what the wind conditions are like and give you a ballpark at the best speed for good economy for those conditions.



2. the piston is normally the first part to melt. The only cooling it has is the oil spray to the underside, nothing like the oil and water that the other parts have and it is aluminum and not iron.



3. for pulling the probe should be pre turbo in my opinion, it will react far faster and be more accurate as to what exactly is going on in the cylinders.



4. personally I would not use a weld in probe. I see no advantage to it. If you ever have a problem with the probe you have to cut it out and re weld another back in. Tapping the manifold is a piece of cake, works fine and makes a change a 2 minute job.



The boost guage is nice to have but not necessary. The EGT guage is far more useful to me. Having both is the way to go. Hope this helps.

 

[redneckdr]

egt

what lsmith said, + use some anti-sieze on the coupling you screw into the manifold. most are brass--in the cast manifold, will sieze, and getting out if you ever need to would be a bear. also works as a sealant to get a good seal.

 

[Batman]

I agree with LSmith.



With that said, if you are only going to put two gauges in, I would use EGT and trans temp. (put the trans sending unit in the hot line)

just my two pennies.

 

[redneckdr]

boost gauge

george, i agree with that, too. most of the time, if you lose boost, you don't need a gauge to tell you. lost boost is not as dangerous to the engine as high EGT, or to the transmission as overheating.

 

[jbone]

I agree with all the posts, used Westach gauges and have been very happy--all others appear to work just as well. I put EGT pre & Post--really want to keep that temp under control with the foot. I have my trans temp in pan just cause it was easier (looking for trend). looks good on the post, and all the power-smokers look!! My 2-cents.