how SHOULD my current combo run

B18B1LS1 · Oct 7, 2018

Recently added Holders 190/100's and MPD s364.5 SXE, so far it's been pretty disappointing. Truck is an 04 Excursion lifted on 40" tires, current mod list is:

190/100's
MPD s364.5 sxe kit
RR fuel
studs and gaskets and orings
built 5r with DPC converter
4" exhaust
AFE intake
Erics ********** tuning

Smokes at idle, and heavy hazes pretty much non-stop when driving easy. EGT's are liveable around town after multiple tune revisions, but pretty high still. Had it out on the highway today for the first time, even locking out 6th and keeping the rpm's up around 2300-2400 the egt's would sit at 1200+ just to maintain speed at even the slightest grade.

java · Oct 8, 2018

That is very similar to the way my truck ran with 190/75s and a 64mm non vgt. I hated it! I switched to a KC Stage 2 vgt and couldn’t be happier.

Extended Power · Oct 8, 2018

The .91 turbine housing is killing you.
Get a .70 gated housing, and don't look back.

B18B1LS1 · Oct 8, 2018

Ugh! I heard this was such a great combo and one of the best street setups there is. I guess not. Is the gate on a .70 big enough to keep ebp in check?

B18B1LS1 · Oct 8, 2018

I did some searching on the interwebs and I don't see very many options for the t4 s364.5, any sources you guys know of? Lots of t3 stuff out there.

shmoozer · Oct 8, 2018

Is your excursion still factory gearing? I feel like that would hurt you the most.

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co04cobra · Oct 8, 2018

Factory 3.73s are hurting you too, assuming it is. Switch back to vgt in a excursion IMO. Driveability across the board should improve.

KCTurbos · Oct 9, 2018

I ran 205/30 and s364.5 and it was fun. I still prefer the quick spool of a vgt... but it was no where near as bad as you are describing.

I am gonna guess there is some sort of issue with your setup. Boost leak, exhaust leak, tuning issue etc...

The other thing is the 190/100s are notorious for being super smokey/hot... but should not haze at idle. Something sounds off.

Here is a video of my truck with s364.5/73/.91 33s and 3.73 gears
https://www.youtube.com/watch?v=Fki7NsqdCdM&t=7s

powerlifter405 · Oct 14, 2018

B18B1LS1 said:
Recently added Holders 190/100's and MPD s364.5 SXE, so far it's been pretty disappointing. Truck is an 04 Excursion lifted on 40" tires, current mod list is:

190/100's
MPD s364.5 sxe kit
RR fuel
studs and gaskets and orings
built 5r with DPC converter
4" exhaust
AFE intake
Erics ********** tuning

Smokes at idle, and heavy hazes pretty much non-stop when driving easy. EGT's are liveable around town after multiple tune revisions, but pretty high still. Had it out on the highway today for the first time, even locking out 6th and keeping the rpm's up around 2300-2400 the egt's would sit at 1200+ just to maintain speed at even the slightest grade.

Like Charlie was saying check for boost/exhaust leaks. Also, the gearing of 3.73's w/ the larger turbo and 40's is another big issue.

Tighten all the intercooler boots to spec. What you think is tight VS using a torque wrench might surprise you. Doing so, I've encountered no more blown boots.

B18B1LS1 · Oct 28, 2018

Still on stock 3.73 gearing. Which I know hurts egt's on the highway in 6th and in lockup. And also obviously makes it slower and works the trans/converter harder. But as far as boost and egt's the gears should be loading the converter harder and adding some rpm which I would think might help more than hurt as long as I'm not lugging it down low. All the shift points are set pretty high to keep the rpms up. 2400 rpm on the highway in 5th should be plenty to stay cool shouldn't it?

I've tested for leaks, and I haven't found anything. The compressor cover has a small leak around the circumference when cold, still need to pressure test it warm to see if it seals up 100%. Supposedly the s300's don't use an oring there?

Just loaded another tune revision today and added a No Limit intake in hopes of some more airflow. Did a short test drive and so far no real improvement. I'll drive more later this week hopefully.