Jwalsh2

Hey! I recently bought a 91.5 w250 with around 120k on it. I am new to diesel mods and I have a few questions. My main issue rn is egt's... When cruising 65-70 in 5th I'm running right around 650, as to when I really stomp on it I get a huge cloud of coal before boost and itl bury the pyro at 1500. From what I've read, 1500* is NOT what you want to see. Any info about egts and or how to fix this would be greatly appreciated. Also current mods include,
Denny T fuel pin, 3200 rpm gov spring, extra long fuel screw, hybrid turbo upgrades(16cm exhaust side/60cm compressor side), 5x.014 SDX injectors, South Bend dual disc street clutch w/550hp rating, isspro gauges, 4" lift kit with new shocks, also 4" from turbo to trans cross member and 5" exhaust on back
That's what I can think of off the top of my head...

thrashingcows

I'm not a big one to mess with the pump settings. But I think with the mods that you listed you are getting way too much fuel, before the 16cm housing can spool up to get more air to clean up the combustion.

I would think you either need to loose the excess fuel, so dump the Denny fuel pin, or go back to stock injectors. Or make more air and go with a 12cm exhaust housing.

dieselJon

I assume you have the Denny T 2 pin?

AFC adjustment is your friend.

Jwalsh2

My intentions for the truck are to make more power, so deleting any existing upgrades was not in mind. I'd like to know what else can be done to help with the issue. All the upgrades that have been done were by the old owner. So there again, I don't know much about them. I've been told a bigger turbo would do a lot but now that u mention the 12mm housing I'm not sure. I do have the coin and the intentions of making it a real power plant. I just lack the knowledge. And yes it's the Denny 2. Thanks

MrFusion

62mm compressor wheel/housing. Definitely lose the 16cm housing and put 12cm on it. AFC tuning. Maybe back the fuel screw out a bit for now. Put a compound turbo set up on it since you're dumping a lot of fuel into into. Ya wanna make power...ya gotta pay to play!

Jwalsh2

Is there some kind of book for dummies on 1st gens? I've read for hours on this forum and still can't quite understand how some of this stuff works. Lol

oliver foster

It takes longer than a few hour to understand tuning a Cummins motor.

Your reading the right book, it just takes a while.

thrashingcows

I've been filling my head with 1st Gen info for about 5 years now. Still don't understand all the tuning, injectors and stuff.

Like Oliver said, it just takes time, and experience to understand things.

probablybroken

look in the stickies for tweaking the VE pump. My suggestion is turning back the fuel screw, popping off the top of your pump and backing out your star wheel as well as backing out the smoke screw and then see where that gets you. Mark everything before you do it though so you know how far you go.

Jwalsh2

Thanks for the advice guys. I will make an attempt tonight! Also, phatshaft turbos? Any suggestions?

1972RedNeck

62fmw/68/12 from the Hungry Diesel.

edwinsmith

If I remember correctly. I assume the thermocouple is placed just before the turbo and not after. If you're seeing 1500 after turbo you can go buy a new turbo for sure.

I found when I put a WG turbo and a pressure regulator to bring the boost up it dropped the EGT's down to a more reasonable level. AN intercooler would also help but water/methanol injection will really help. That's my next trick when I get back to working on mine.

Basically the more/cooler air you have the more fuel you can dump in there to keep EGT's down. There's guys on here who know a lot more than I do though so stay tuned and I'm sure they'll chime in.

Edwin

Jwalsh2

I really appreciate all the info in this guys. Thanks!!

oliverbutthead

I turned my starwheel up two turns and smoke screw up one turn recently and almost eliminated all my smoke before boost. Mine boosts quicker than yours probably because I run the HE351CW and I believe it has the 12cm exhaust housing. Boosts way faster than stock.

I never really understood the fine adjustments before either but kept reading and you just have to try it. Very easy! Just try to keep track of how far you move things in case you need to put them back.

You may have to move your adjustments a little more than I did since you have bigger injectors and bigger turbo housing. Performance will not suffer with these adjustments.

MARF75

351cw has a 9cm exhaust housing