High pyrometer readings on 6.9L IDIT

[R Kingsbury]

Hello Oilburners! im new and looking for as much insight on these IDIs as i can lay hands on.
Ive got a 1984 F250 with a 1986 6.9L IDI with what I hope is an ATS 093 turbo (mismatched parts, at least the airbox and exhaust of an 093) and im looking for tricks to knock the EGTs down on it. ive found that more air from the turbo (13 PSI currently) will cool it but without studs (and the pump maxed out) im concerned for the motor. I know im asking for a lot from this motor already with the amount of fuel and air on stock head bolts but im wondering if im missing any easy tricks. Timing is also bumped up quite a bit from stock to knock the EGTs down at higher RPM (pumps wore out).

 

[Nero]

Turning the pump down a pinch is the easiest and cheapest way. The proper way would be to intercool it.

 

[R Kingsbury]

the intercooler plan is already in the works, is there anything i can do physically internally to the motor/pump (or another motor) beyond turning the fuel down? Im all about labor over cost, all mods are on the table and the next motor will already have studs and shaved pistons.

 

[Nero]

Running a larger exhaust and an intake that sucks colder air will help, but for cost of those parts, gains are minimal.

 

[R Kingsbury]

On the same note as the exhaust is the turbo restriction on the (assumed) 093 known to cause more heat than an alternative turbo? I know the turbo that we put on this motor has a bigger exhaust snail than the old turbo and that seems to help, but is there any known upside to an even bigger turbo or is it no longer a noticeable difference?

 

[gnathv]

What temps are you seeing?

 

[KansasIDI]

6.0 intake box

Just wondering if anyone has put a 6.0 Powerstroke intake on a 7.3 or 6.9 IDI. Seems @snicklas was talking about how the intake box bolts up to the battery tray. If no one has tried it I may well just try it anyway, if it don’t work my buddy with a 7.3 PSD said he might buy it off me.

www.oilburners.net

It makes a difference. If you have a muffler, maybe get an open flow unit. If you are straight piped then you’re probably pretty close to max flow. What diameter exhaust pipe do you have? I recommend at least 3.5”

 

[KansasIDI]

6.0 intake box

Just wondering if anyone has put a 6.0 Powerstroke intake on a 7.3 or 6.9 IDI. Seems @snicklas was talking about how the intake box bolts up to the battery tray. If no one has tried it I may well just try it anyway, if it don’t work my buddy with a 7.3 PSD said he might buy it off me.

www.oilburners.net

It makes a difference. If you have a muffler, maybe get an open flow unit. If you are straight piped then you’re probably pretty close to max flow. What diameter exhaust pipe do you have? I recommend at least 3.5”

Just make sure you read to the end… for a while I wasn’t that happy with it.

 

[Black dawg]

What temps are you seeing, and under what conditions. How much timing, and what injection pump?

I have a 6.9 pump on my 7.3, and even with the pump cranked, it is pretty mild

 

[R Kingsbury]

What temps are you seeing, and under what conditions. How much timing, and what injection pump?

I have a 6.9 pump on my 7.3, and even with the pump cranked, it is pretty mild

cruising near governor limit its hanging out at the 1050 mark, (probe is smack in the middle of the drivers side manifold) while going up the 9% to shingletown at 55 mph (2300-2400 RPM) it holds out at 950 and creeps up slowly till i back out. timing is set by trial and error for the coolest EGTs and by ear, and as far as im aware the pump is an original 84 era 6.9 pump thats been pulled apart and put together repeatedly. I have to agree its mild even all the way up. All of these conditions are just the truck hauling itself, no trailer.

Exhaust is 3" all the way through with a flowthrough muffler, ATS box is currently breathing the under the hood air since i havent gotten the air scoop installed yet.

Edit: includes a 3" downpipe

 

[Nero]

If it's not going above 1100 F I wouldn't worry about it.

 

[Kdo58]

Sounds normal to me, that's what mine does going up long steep hills.

 

[catbird7]

Easiest test would be turning the fuel down one flat and see what changes.

 

[gnathv]

Put a temperature probe under your hood and you’ll discover that at speed your under hood temp is the same as outside temperature. There’s a lot of air coming through the grill of your truck. The heat comes in when turbo compresses the air, intercooler is the ticket. Your EGTs are pretty normal maybe even on the low side.

Less fuel less everything EGT, power, etc

 

[Cubey]

Put a temperature probe under your hood and you’ll discover that at speed your under hood temp is the same as outside temperature. There’s a lot of air coming through the grill of your truck. The heat comes in when turbo compresses the air, intercooler is the ticket. Your EGTs are pretty normal maybe even on the low side.

Less fuel less everything EGT, power, etc

Agreed. The 27ft RV pulling 1500+ lbs through the mountains without "cold" air intake, due to the rigged up nature of the ATS 085 kit was slow and hot, as low as 1st gear and 20-25mph at 1000-1100° EGT.

55mph at 900-1000° on a 9% grade in a pickup sounds pretty decent.