How can I Lower My Egt's

[Mopar1973Man]

Wash it out with water...

 

(Please don't do this it will do damage to a diesel... Just trying to be a bit funny)

[rburks]

Wash it out with water...

 

(Please don't do this it will do damage to a diesel... Just trying to be a bit funny)

IS THAT FROM ERIC THE CAR GUY     OR     MIKE THE TRUCK GUY      

[Mopar1973Man]

IS THAT FROM ERIC THE CAR GUY     OR     MIKE THE TRUCK GUY      

 

[KBecker443]

I’m also having an EGT issue was hoping a new turbo would really help. It hasn’t quite made the difference I was hoping for. Cruising around my egts are 8-950 and normal freeway driving 65-70 I’m pushing 11-1200. I have a 99 with 125hp Injectors, S&B CAI, 4 inch exhaust, BWS364SXE and a quadzilla. My worry is when hunting season comes around having issues pulling my 5th wheel. Anything I can do or check to help lower my EGTS also my MPG is 14.5 and has dropped since the new turbo from 16.5

Edited March 23, 2018 by KBecker443

[Me78569]

You are underfueled for the turbo so you are having to use duration to make up for it.   what are the full specs of the turbo? 

 

I would stepup to some bigger injectors, 7 x .012's or similar +-.001 get V2 on your quadzilla and go from there.    

[Mopar1973Man]

First off you running 37" tires. What is your gear ratio? Hopefully 4.10 or higher.

 

Edited March 23, 2018 by Mopar1973Man

[Me78569]

2 minutes ago, Mopar1973Man said:

First off you running 37" tires. What is your gear ratio? Hopefully 4.10 or higher.

 

Completely missed that.    How about 5 speed or auto?  an auto paired with 3.55's and 37 would be a nightmare setup

Edited March 23, 2018 by Me78569

[KBecker443]

BWS364SXE waistgated .70AR T3 HX40 this is the turbo Powerdrivendiesels reps recommended for me. I ordered it before I joined this forum. 

[Mopar1973Man]

37-inch tires on 3.55 gears is a final ratio of 3.00:1 which is WAY TOO TALL geared! This will create a HUGE amount of EGT's. For towing performance, you would want 4.88 gears for 37" tire for towing. 

Edited March 23, 2018 by Mopar1973Man

[KBecker443]

I believe it’s the stock gearing I’m the 3rd owner of the truck and when I bought it the previous owner told me they never touched the rear end. 

[Mopar1973Man]

Change the gears to 4.10 if you not towing. 4.88 if you plan on towing. The whole EGT problem will go away. 

 

Looking cool on 37" inch tires comes with a huge price tag. It will be about $4,000 to re gear the axles. I've just finished this project with a local gent with 37" tires. Now the EGT's are good and low and the power is super. 

Edited March 23, 2018 by Mopar1973Man

[KBecker443]

Alright will check that out for sure, didn’t realize Gearing would effect EGTs that way. 

Edited March 23, 2018 by KBecker443
Spell check

[Mopar1973Man]

Absolutely its called rolling resistance. Final gear ratio of 3.00 is way to high of rolling resistance and put a huge amount of load on the driveline and drivetrain and the engine so the net result is high EGT's as the truck is pull ing in a super high gear it was never design for.

[AH64ID]

2 minutes ago, KBecker443 said:

Alright will check that out for sure, didn’t realize Gearing would effect EGTs that way. 

 

When you don't have the mechanical advantage of gearing the motor has to work harder to keep the tires rolling. This effect, combined with the reduced rpms of tall gearing makes for higher load at lower rpms and you run higher egts.

 

Just a little example...

 

lets assume it takes 400 lb/ft of tq to make the truck run 65 mph in OD.

 

With 3.55's you're running around 1500 rpms. With this gearing the motor has to make 169lb/ft.

 

With 4.10's you'd be running around 1730 rpms. With this gearing the motor has to make 141lb/ft.

 

With 4.88's you'd be running around 2060 rpms. With this gearing the motor has to make 119lb/ft.

 

The work required doesn't change, but the motor isn't working as hard with lower gearing.

 

[Me78569]

Yea 37's on 3.55 gives you an effective gear ratio of 3.00:1 out back.  You have to be doing 80 before you have enough RPMS in OD to get the 64mm turbo spinning at any real speed.  

 

Regear or drop the tires to stockish and your issue should get much better.  I would still prefer to see much bigger injectors with the 64 so you aren't forced to use a ton of duration to get the fuel you need.

 

 

[Mopar1973Man]

5 minutes ago, Me78569 said:

would still prefer to see much bigger injectors with the 64 so you aren't forced to use a ton of duration to get the fuel you need.

 

Most likely won't need the turbos after re-gearing the axles. 

8 minutes ago, AH64ID said:

With 4.88's you'd be running around 2060 rpms. With this gearing the motor has to make 119lb/ft.

 

Perfect RPM range for towing on 37" inch tires at 65 MPH.

Edited March 23, 2018 by Mopar1973Man

[Me78569]

Here's a gearing calc we built to figure out tires vs rear end

 

 

 

 

[KBecker443]

So 4.88s and what size Injectors if I was to upgrad them? 

Also how do I determine which axles I have? 

[Mopar1973Man]

I would do the gears first. Then the whole tuning aspect will change so don't do any injectors or turbos till you get the gearing done. I'm betting the turbo(s) you got now are too big.

Edited March 23, 2018 by Mopar1973Man

[Me78569]

Gears first, no amount of other mods are going to solve your issues.  the engine simply has to work too hard to move down the road.  

 

 

Once that is done you shoudl define a power goal.  with the 64mm turbo you have ~550hp worth of air ( i dont know exact flow on the turbo), which means you need 7 x .011's or similar to match that.  Under using a turbo is just as bad as over using.  you want to be in the fat part of the turbos map.  To low in the map and you get high egts and poor performance too high in the map and you get high egts and poor preformance.

Edited March 23, 2018 by Me78569