Engine/Transmission (1994 - 1998) New parts are on....what is the deal with my EGT temps?

[CMartin]

I finished installing some parts today. I installed a TST #10 plate, AFC springs, K&N FIPK kit, 3½" downpipe with removed cat and muffler, plate full forward.

Under WOT in 4th gear the truck pulls HARD and boost hits 35psi (or more). The hottest my exhaust got was 950°F. I have not yet installed my 16cm² turbo housing or my 370 injectors, will these increase the EGT temps?? The plate alone with the K&N and the AFC springs greatly increased the performance, and the smoke is minimal. I was under the impression that just the #10 plate may create very high EGT temps but I am not experiencing this problem?? Is it only when towing under WOT or something?



How much MORE power am I going to feel with the 16cm² housing and the 370 marine injectors. I also plan on getting the 3 or 4ggsk... . any opinions on which is better? I would assume that the higher RPM is better, but at what cost to longevity or reliability?



Thanks, CHAD

 

[the whale dog]

Chad

Yes your EGT will go up when towing and during long climbs at WOT at the bottom of high gear The new turbo should lower EGTs as it will move more air just watch the pyro as it will sneak up fast when it decides to go up hope this answers your question Kevin

 

[tURBOdIEZEl]

chad. with the 4kgsk you will need to put in heavier springs. everyone with the 3kgsk seems to be pretty happy. my new bombs are about to be in (370's, 191's, 3kgsk, 16cm2 housing, #10 plate, and AFC springs) so i will let ya know how my pyro runs under WOT. hope that helps ya.

 

[JGK]

Chad,



I assume your pyro is pre-turbo. 950 degrees seems low, but you said that was in 4th. Shift into 5th and stay in it and I'll bet you'll see higher numbers.



Get either of the GSK kits, but as said, the 4K kit "requires" heavier valve springs to avoid valve float. But the kits really help with improved upper end rev range. However, that will contribute to higher EGTs up there.



You will notice a difference to EGTs as well as power with the 370s. You'll like them.



On mine, with a real hard run through the gears, the EGTs will stay under 1350 until I stay in it in 5th, then all of a sudden as I get up to and pass 100 MPH, they'll jump quickly to 1500+. Fortunately, I don't drive that fast too often!



-Jay

 

[CMartin]

Chad,



I assume your pyro is pre-turbo. 950 degrees seems low, but you said that was in 4th. Shift into 5th and stay in it and I'll bet you'll see higher numbers.



Get either of the GSK kits, but as said, the 4K kit "requires" heavier valve springs to avoid valve float. But the kits really help with improved upper end rev range. However, that will contribute to higher EGTs up there.



You will notice a difference to EGTs as well as power with the 370s. You'll like them.



On mine, with a real hard run through the gears, the EGTs will stay under 1350 until I stay in it in 5th, then all of a sudden as I get up to and pass 100 MPH, they'll jump quickly to 1500+. Fortunately, I don't drive that fast too often!



-Jay

Actually, my EGT probe is post turbo... . right behind the exhaust housing in the down tube elbow. I would venture a guess of about 4" from the turbo itself. Ok, so right now my engine goes to 3300 rpm and falls on its face, what will the 3gsk's do for me? What rpm will it allow the engine to rev to?

 

[Andy Redmond]

One rule of thumb. . add three hundred degrees to post turbo temps to equal the real numbers.



Plug up your hole and put your thermocouple up on the manifold so you can get more accurate readings.



Stay less than 1250 deg. or you'll pay the piper. . eventually!



Sounds about normal for the # 10 plate. If you tow heavy and or in high altitude you will need the HX40 or more eventually. (with the 370's and gov springs).



The 16cm2 housing will let you run more throttle a bit longer before reaching danger zone. You can alway slide the plate back towards the firewall in . 010 or . 020 increments to balance egt's once all the mods are on the truck.



>>What will the 3k springs do?



They will prevent defueling until the high gov. point 3-3300 in your truck. .

You know that rush and hard pull from 1700-2200, it keeps pulling like that! :-laf



Be nice to your clutch, its next!

 

[boondock]

Is your clutch stock?? Won't be lasting with a #10 all the way forward and 39" tires. Once you put the 370's that thing will be slipping everytime you get into it. Move you egt to pre turbo.

 

[Bob4x4]

If you have a california truck the #10 plate is mild! The federal version as a whole new ball game.



Bob

 

[Cooker]

At WOT 950 post turbo is definitely over 1300 pre-turbo. If you are adding more fueling, I agree that moving the probe pre-turbo would be best.

 

[CMartin]

Truck is not a CA truck... . it is federal from Texas originally. No EGR!

Yes my clutch is stock, but not for long... maybe a couple of weeks. The reason I put the EGT POST turbo is because I did not want to get the metal shaving down inside the manifold while drilling. They will go right through the trubo won't they?

Ok so I guess it is time to put the 370's in, the 16cm² housing and the 3gsk springs... . and of course a clutch.

If I am over 1300°F now (pre turbo) then how long does it take to ruin the nigine in that fashion... and what is MAX temp?

By the way, thanks so much for all the help and answers so far.

 

[Bob4x4]

I would not use that 300 degree difference rule! I have seen 600 degrees difference on my lil 94 (425/1100)



Bob

 

[RT66DOC]

Put some grease on the drill and tap. Then stick one of those skinny pencil type magnets in there a few few times and move it around. You'll get most everything out and what's left [if any] won't hurt the turbo. Worked fine for me many miles ago.

 

[CMartin]

Put some grease on the drill and tap. Then stick one of those skinny pencil type magnets in there a few few times and move it around. You'll get most everything out and what's left [if any] won't hurt the turbo. Worked fine for me many miles ago.

That's a good idea, I should have thught of that because I do heli coils on spark plugs all the time at work and thats what we do. Anyway, atthis point it does not matter because I broke my rear yoke last night so this morning I went out and started to pull the turbo exhaust housing to change it to the 16cm² housing. I figured now was a good time since I will be down for a week or more waiting for parts. Well, 3 of the 4 turbo-to-manifold bolts broke so I am pulling the manifold (taking a break at the moment ) and taking it to work on Monday to remove the broken bolts. At this point, I will throw it in a vise and just install the EGT probe at that same time

 

[RT66DOC]

Do you know the correct location for the EGT probe in the manifold?



Also, you might take a look at the manifold at the #1 to check for signs of shrinkage. I recently read here somewhere that one of the gents "relieved" the slots in the manifold a bit to allow for shrinkage. Don't know if that's a good idea or not but if it is, now would be a good time to do it. Hey - as long as you're already down for a week you have time to order an ATS 3-piece.

 

[CMartin]

Well, I don't "KNOW" the correct location you might be talking about, but I WAS going to put the probe near the flange that the turbo mounts to. I figure this way the probe will see the temp accurately from all 6 cylinders??

***EDIT***Actually, I just found THIS... . so I would say I DO now know where it goes

http://www.dieselpage.com/gipda.htm



WHat is an ATS 3 piece? I am new (VERY new) to Cummins so there are a lot of parts/performance upgrades I am unfamiliar with.

Thanks

 

[JGK]

CMartin,



An ATS 3-piece is a 3 piece exhaust manifold. The turbo mounts to the center section and it covers cylinders 3 and 4. The end pieces use tight fitting slip joints to join to the center section and they mate up to 1 and 2, and 5 and 6.



The advantages are that they flow better and eliminate the problem the stock manifold has of shrinking over time, which, on occasion, has broken off the mounting ears at number 1 or number 6 cyliders on the head.



It'll set you back about $465, more or less, as I remember. If you decide to get one, search the threads here and/or inquire as to the techniques of fitting the pieces together and mating to the head. If done right, its pretty easy. If done wrong, you'll cuss it all afternoon.



-Jay