Lets talk about PSD 7.3 Boost & Pyro #s

[KS Toy]

I have an 02 PSD with a 7.3 Aftermarket intake, 4" exhaust from the turbo back and have a Superchips programmer and am monitoring the system with a Bully Dog monitor. I have the programmer set on the lowest (tow) setting. A friend of mine gets in the truck and sees that the high boost reads 31.6 and tells me that I am lucky the engine is still in one piece. I got the reading running empty going up a hill. Just a couple of weeks before I had a reading of 30.4 pulling a loaded 25' enclosed trailer up hill so I do not believe I am getting a false reading. So... is this to much boost or what? Also, why is the high pyro reading only @ 819? (post pyro) I would guess with that kind of boost the pyro reading would be higher.

[Hottrod81]

I would cut your losses and take the chip out. If it fingerprints the computer and something goes wrong with the truck, your warranty is voided, that is if you still are under one.

[bigtoyfreak]

I have a 2000 PSD with a 6 speed, 3.5" downpipe to 4" exhaust with no muffler, super chip (80hp setting) and an upgraded compressor wheel. On a good long steep climb with the camper in the back and toy on the trailer (18.5k total) I only hit 900 to 1000 degrees on a hot summer day. If you have an after market intake ( I just run a K&N filter) and are running a towing setting on the programmer 819degrees doesn't seem to low to me. The most boost I've ever gotten with my truck is 27psi. The check engine light starts to flicker off and on when the boost is at max.

[BurnedBronco]

hell my 97 pegs the pyro at 1100 to 1200 every trip out with it. i have to back out.

[CSP]

That's about what I would expect from a post turbo pyro, especially since you weren't pulling a load.

[StoopidMonkey]

Isnt the stock turbo only efficient up to about 26 PSI?

[Robert]

Boost pressure can vary according to atmospheric pressure, temperature, etc.
I don't think 31 PSI is too much. I see big bore engines that run boost between 50 - 80 PSI without problems. 800 degrees for a pyro is definitly not very high.

[TurboDiesel444]

You really need to move your pyro probe to pre-turbo. Post won't tell you shit. I have an AFE intake, 4" turbo back straight pipe and SCMT set on 80 and only get over 1000 degrees pre turbo if I plant my foot. Max boost I've seen is about 24 psi. As long as you aren't hitting 31 psi on a regular basis, I think you're ok. The Ford engineers say 25 psi is the limit for the stock turbo which is when the SES lights up.

[Colorado Ron]

I have snorkel(cold air ) 3 positions chip, 4 inch down pipe and 5 inch open exhaust with a 6 spd. I hit 31 PSI all the time. Never had a problem. But my pyro numbers are alot high. I have mine mounted in the back of the driver side manifold. I hit 1200 often.

[Azrckcrawler]

The Ford tubos use bushings and are supposed to be good for a max of 25psi (forget what rpm that is). I didn't want to push it on mine so I installed a 25psi blowoff valve. Got it from Mcmaster Carr for a couple bucks. I'd think about moving that pyro sender, I bet your 800 degrees is really 1200 or more.

[DSI]

post turbo pyro's are shit... 300-700 degree variance. also, the edge attitude, and bullydog outlook tie into the maf sensor for the boost reading, so they are not alway's the most accurate. i've seen attitude module's show 58psi not even running hard when the analog gauge showed 23psi

[4x4not]

That would be my first guess.... post-turbo pyro temps? I know I have a CTD and not a PSD, but I can hit over 1200° pre-turbo, and 33# of boost. On a stock truck, no load WOT up a big hill. Once I bomb we'll see how that changes

[DSI]

Originally Posted by 4x4not

That would be my first guess.... post-turbo pyro temps? I know I have a CTD and not a PSD, but I can hit over 1200° pre-turbo, and 33# of boost. On a stock truck, no load WOT up a big hill. Once I bomb we'll see how that changes

living at 4500+ft i can hit 14-1500 just trying to merge into traffic if i'm not paying attention and i can only make 27-28psi up here, where as low level i can peg my gauge easily...

[Rallye]

Originally Posted by Azrckcrawler

The Ford turbos use bushings and are supposed to be good for a max of 25psi (forget what rpm that is)....

Ford doesn't make turbos - Garrett does. The Garrett GTP38 that's found in the 99-03 7.3 PSD has fully floating journal bearings that use an oil damper on the ID and OD of the bearing. Thrust load on the stock turbo is taken up by a standard plate type thrust bearing that uses an oil damper as well. If you are regularly boosting past stock of 25-27 psi, you run an increased risk of thrust failure (notice that I did not say you WILL fail). Also, if you are pushing boost limits, you also are at higher risk for mechanical failure of the wheels due to overspeed condition - especially when hauling heavy loads at high(er) altitude.

And, as others have pointed out, post turbine temps are pretty much meaningless, as far as giving you information about how much you are stressing the components. By definition, a turbine extracts heat from exhaust flow to make mechanical power, so downstream temps can be hundreds of degrees less than pre-turbine temps. For Class 8 Diesel apps, 1400F is usually the rule-of-thumb pre-turbine hard limit. for the PSD, 1200 is hot, but probably not severely hot. Remember that turbine inlet temp is greatly affected by speed and load, so if you are cruising around town at 5psi, your temps are going to be a lot less than if you're hauling 12k# over the pass at full boost.

As for wheel clearances, shaft axial play is uually about 0.003"-0.004", and for radial play, if your insert a piece of regular printer paper between the wheel and housing and push the wheel with your finger, if the papers doesn't tear, it's usually OK.

Just the opinion of a lowly turbo engineer...

Mike

[FF3PM]

Post turbo pyro probe location will vary quite a bit from pre turbo pyro probe location readings. Pre turbo pyro probe readings are considered the benchmark. There is no constant number you can add to post readings to equal pre readings due to load, RPM, and other variables. Just for conversation add 300-400 to your 800 and now you are in the more realistic range. Stock SD turbos will not live long making boost nearing 30psi. The map on them falls off around 25psi, meaning they loose efficiency, and start adding a lot of heat to the intake. Boost and EGT do not have any correlation to each other. As far as the engine staying together @ 30 psi boost, your friend is incorrect. But also 50-80 psi boost on a stock PSD isn't going to happen with a stock turbo let alone a single turbo, head gaskets, heads, or head bolts, and the PMR's.

[tdavis]

My '01 Superduty with Edge Juice w/Attitude, and pre-turbo EGT probe hit 1200F in Utah, at 20psi..

I have never seen higher than 20psi with the Juice in milage/tow/drive modes.

[wideopenDiesel]

You really have nothing to worry about keep your programmer ..I like my Pre turbo readings ..I think it's more accurate..the Post as it has been stated above is not quite as accurate.. With pre turbo , when towing I try to stay below 1200* anything above that I back down..though it is few and far between, as far as your Boost I have a stock Turbo and it is nothing to se it up around the 32-34lb mark been like that for 3 years now and no problems at all ..something you might wanna watch is shutting down ..when towing hang aroung and let the Engine Idle for a bit before shutting down. At Pre Turbo I try to never shut mine down about 300* and a post I would say at least 200*.. Hope this helps

[4x4not]

On the topic of cooling down... I feel it is ABSOLUTELY essential to have some kind of turbo timer for a turbo diesel truck, especially one that is used to tow and/or is bombed. I have a BD X-monitor w/ a cool engine shutdown module, and have it set to shut the truck down @ 278°F, pre-turbo. I could probably get away with a little warmer but even on a hot summer day (like yesterday, in the 90's) driving it kind of hard it will cool off in less than 3-4 minutes.

[CanuckJeeper]

Dang you guys are running cool compared to mine!

I have a '01 F350 with:

TS Performance 6-way chip
AFE Stage 2 air intake
Flo-Pro 4" exhaust

If I put the chip in the highest setting, I can see the 1300-1400F (post) DANG fast. 10 seconds or so of WOT and I'm at that rating.

Any ideas to lower the EGT's?

JP

[wideopenDiesel]

What code is your Computer...a simple programing change from TS could fix that problem

[KS Toy]

Ok, thanks for the info. I have it set to de-fuel @1250 so there is not a problem there. The monitor has another set of leads for the pyro so it looks like I need to hook them up pre-turbo. Also, I never did see the SES light come on but I might have been looking at the cloud of black smoke if it did flicker.

[PCJEEPN]

My 2000 F250 will only get up to about 22 psi max. I don't think I have seen it any higher. My pre-turbo EGT's will run up to 1000-1200 when I stomp on it. Usually will not climb over the 1200 mark. I have 4" down pipe, 5" muffler out, Edge Eolution programmer, and aftermarket open element filter. Keep in mind that I am running at sea level.

Stephen

[wideopenDiesel]

Originally Posted by KS Toy

Ok, thanks for the info. I have it set to de-fuel @1250 so there is not a problem there. The monitor has another set of leads for the pyro so it looks like I need to hook them up pre-turbo. Also, I never did see the SES light come on but I might have been looking at the cloud of black smoke if it did flicker.

With the SES light it should have stayed on for a while if you set it off with to much boost.. They will stay on for several minutes .but will reset with a simple reset of the key.. I have a Boost regulator inline from the turbo to the MAP sensor I have my boost guage line in line before the regulator. This is now sounding like your guage, because it it electronic, may need to be re-calabrated??

[roundeye]

With all the talk about boost, pyro etc. I bought a evolution programmer for my 02 F350. Then I decided to sell my Ford. So, now I have a programmer for sale. It's the EEF 1000 unit. I paid 408 bucks for it and it's brand new.
Anyone interested, call me at 530-642-8003 and I will give you a great deal.