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The reason compounds are so popular on Cummins trucks is because of the smaller displacement, which means they need more boost to make the same amount of power as a 7.3 and they are't moving as much air to spool a large turbo, the l6 also has a slightly lower power curve than a V8 7.3. A 5.9 Cummins truck with 600hp or more with a 66mm or larger single is going to be laggy and slow to spool down low no matter what you do, where as a 7.3 can spool a 68mm or larger pretty easily if its set up right. Even some of the highest HP 7.3s have tried compounds but ended up making more power on a large single. I am not saying compounds can't be made to work on a 7.3, because they can but a properly sized single turbo for your setup has proven to be all you need.
Finished up some 36 bolt beadlocks mounted on stock 16" steel wheels with grooved Duratracs.
Also got the "high flow outlet" for the gtp38, it also has the ebpv delete cast into it. Looks like I will need to open up the wastegate portion to optimize flow.
Quite a few people out there running compounds actually, you just don't hear much about it unless really looking for it or poking around on performance oriented sites/forums/groups/etc.
Dan Kropinak of SDK knows about compounds
Mario G at Night Shift Diesel runs triples (2 s366sxe over a s467.7 in the valley) with 350/200s.
Scott Morris (one of the links for Driving Line above) was running a monster s110 atmosphere with 400/400.
The fartbook group "7.3 Powerstroke Performance" and Powerstroke Army forum have quite a bit of info/threads about compounds. Compounds on a 7.3 will make power down low, so most of the time they aren't even considered remotely "safe/reliable" unless doing a fully built engine with billet rods, girdle, fire-ringed head gaskets, yada yada.
Quite a few people out there running compounds actually, you just don't hear much about it unless really looking for it or poking around on performance oriented sites/forums/groups/etc.
Dan Kropinak of SDK knows about compounds
Mario G at Night Shift Diesel runs triples (2 s366sxe over a s467.7 in the valley) with 350/200s.
Scott Morris (one of the links for Driving Line above) was running a monster s110 atmosphere with 400/400.
The fartbook group "7.3 Powerstroke Performance" and Powerstroke Army forum have quite a bit of info/threads about compounds. Compounds on a 7.3 will make power down low, so most of the time they aren't even considered remotely "safe/reliable" unless doing a fully built engine with billet rods, girdle, fire-ringed head gaskets, yada yada.
Have read a lot of what those guys have to say and their setups. Cant say I agree with the general statement of needing a fully built motor to be "safe/reliable" for moderate power levels. Then when you say "moderate power levels" all that is recommended is T4 T4 T4.
Have read a lot of what those guys have to say and their setups. Cant say I agree with the general statement of needing a fully built motor to be "safe/reliable" for moderate power levels. Then when you say "moderate power levels" all that is recommended is T4 T4 T4.
It probably could be ok at "moderate" (meaning still low like up to 450 hp) without built bottom end, but the compounds will make a lot more boost and will do it quickly and down low in the rpm band. Plus the setup will still be very expensive (turbo/piping wise) like the big setups. The 7.3 has enough displacement that it can run a bigger single than other setups and still spool it quick(ish).
However, I still think that having an easy/less expensive option for "tow" or "street" compounds for the 7.3 would be awesome. I think the drive-ability (spool up time) would greatly improve. In theory, could allow you to run slightly higher gearing, but still spool up and have power down low. Thus extending power band and allowing a faster "cruise speed" of say 75-80 mph at 2000-2100 rpm. Just my thoughts.
Well...
It's firearm deer season in Michigan so everything is on pause until tags are filled.
I am using the Excursion for my hunting rig though. Logging roads are rough and muddy, glad I have the beadlocks and grooved tires. A mild derail here (i dont care)...was having issues with the truck bottoming out in the front end on big bumps. Stock bump stops have fallen off and the soft front springs in the Ex cause steel on steel contact. Thought about swapping in new U-codes to pull the axle away from the bump stop mount and bring up the front end a little bit. Decided against it and went a different route to smooth out the ride.
First of all is bump stops, I have ran this style of bump in a different applications. They are bump stops for lowered trucks. Lowered trucks have little to no suspension travel so a soft bump stop is important to ride quality.
These are the stops. I run similar on my F350 and these things can absorb serious shock without transferring it to the cab. For example...Stock SD bumps and a large 6-8" rut jars at around 5mph, these bumps can soak up the same rut at 15mph without jarring.
To bring the front end up a little bit and retain the soft stock leafs I decide to go with a longer shackle. To be determined if they add 1.5" or not as the length of the shackle is not listed.
Lastly, for a ride that really soaks up bumps whether going slow or not...shocks. I have ran a few monotube Nitrogen shocks, KYB monomax, Bilstein 5100 and have always thought the Nitrogen preload hurt ride quality at slow speeds.
Monroe Gas-Magnum is a monotube shock without a Nitrogen charge (they do not extend on their own) but is a very heavy duty wide body shock. These shocks do not add spring rate to the leafs and do very well off road.
Hah! Cool. Good luck with your hunt. You gave me a bad case of beadlock envy in the other thread btw. Good info on the bump stop, springs and shocks too.
I am working to emulate your diff housing traction bar btw.
Hah! Cool. Good luck with your hunt. You gave me a bad case of beadlock envy in the other thread btw. Good info on the bump stop, springs and shocks too.
I am working to emulate your diff housing traction bar btw.
The way it was mounted to the diff cover bolts sent too much shock through the small 5/16" bolts. In turn it hammered the differential cover causing them to loosen and start leaking diff fluid. I think a way around this is to use a solid welded plate diff cover similar to something used for off road use for the mount.
This way there is 100% bolt engagement in the housing instead of the top 2/3 bolts. May still have leaking issues due to the fact that the RTV compresses. Concept works good but not sure how well it can handle a prolonged beating.
Next plan is to likely build a bolted mount that is weldrd to the axle tubes and comes across the top of the differential. Plan to keep the traction bar and shackle in the location I have it now with a modified mount.
