Please evaluate this plan. Newb with bone stock 92 D250
01-28-2016, 05:45 PM
#1
Registered User
Thread Starter
Please evaluate this plan. Newb with bone stock 92 D250
First off, I'm brand new. I just got my this truck and I want to make a few mods to improve the performance. I've been doing a lot of reading, but I want the experienced people to tell me if my plan is close or way off.
I have a 1992 D250 5.9 auto. The truck has 237k miles and is a well maintained fleet truck.
My goal is 300 Hp, 650 ft lbs of torque. I would prefer minimal smoke and close to stock mileage while cruising. I will use the truck to pull a single car trailer with a 1/2 ton truck on it, about 7000 lbs.
My first mods will be a boost and pre turbo EGT gage. After that below:
Fuel Pin
3200 governor spring
turn full power fuel screw in (2 turns?)
4" downpipe and exhaust
Open up the stock airbox
Do I need injectors? Should I plan on them just because of the mileage of the truck?
How about turbo upgrade? I'm thinking 98 manual trans HX35 for the higher wastegate setpoint, but maybe I just need a 14-16cm^3 exhaust housing for my H1C?
How does this sound?
Thanks.
I have a 1992 D250 5.9 auto. The truck has 237k miles and is a well maintained fleet truck.
My goal is 300 Hp, 650 ft lbs of torque. I would prefer minimal smoke and close to stock mileage while cruising. I will use the truck to pull a single car trailer with a 1/2 ton truck on it, about 7000 lbs.
My first mods will be a boost and pre turbo EGT gage. After that below:
Fuel Pin
3200 governor spring
turn full power fuel screw in (2 turns?)
4" downpipe and exhaust
Open up the stock airbox
Do I need injectors? Should I plan on them just because of the mileage of the truck?
How about turbo upgrade? I'm thinking 98 manual trans HX35 for the higher wastegate setpoint, but maybe I just need a 14-16cm^3 exhaust housing for my H1C?
How does this sound?
Thanks.
01-29-2016, 10:59 AM
#3
Registered User
I love the plan.
It sounds about right.
If you start you list as you wrote it down above, you will know if you need that HX-35 by the time you get there.
You will learn from watching the boost and EGTs and by driving your modified truck while towing.
Welcome to DTR and enjoy the build.
One thing I would add is do some work to that auto if you want it to hang along with those engine mods.
I will let the auto trans experts advise you there, but a low stall converter and stronger flex plate should be on your shopping list.
It sounds about right.
If you start you list as you wrote it down above, you will know if you need that HX-35 by the time you get there.
You will learn from watching the boost and EGTs and by driving your modified truck while towing.
Welcome to DTR and enjoy the build.
One thing I would add is do some work to that auto if you want it to hang along with those engine mods.
I will let the auto trans experts advise you there, but a low stall converter and stronger flex plate should be on your shopping list.
01-29-2016, 12:50 PM
#5
Registered User
01-29-2016, 03:38 PM
#6
Registered User
01-29-2016, 06:16 PM
#7
Banned
sounds like a very sound plan. especially the gauges BEFORE you get crazy with the mods.
check out The Hungry Diesel for fuel pin and gov spring. he drives one of these things and designs parts from real life testing. great guy to work with too.
as others have mentioned, the trans will be the weak point. if money allows, look into what upgrades can be done for reliability/longevity. i don't believe in automatic transmissions, but hopefully some auto guys on here can point you in the right direction!
check out The Hungry Diesel for fuel pin and gov spring. he drives one of these things and designs parts from real life testing. great guy to work with too.
as others have mentioned, the trans will be the weak point. if money allows, look into what upgrades can be done for reliability/longevity. i don't believe in automatic transmissions, but hopefully some auto guys on here can point you in the right direction!
Trending Topics
01-29-2016, 07:30 PM
#8
Registered User
Welcome...and congrats on the new truck!
I agree with the others, your list of mods is spot on. But The 12cm exhaust housing might be a tad too small for an auto truck. The 16 or 14 would probably work better IMO.
I have a 14 on my crewcab, with the NV4500, and I like it. Runs a tad more boost on the HWY then I would like to see....but around town it's good. I drive fairly sedate though..
I agree with the others, your list of mods is spot on. But The 12cm exhaust housing might be a tad too small for an auto truck. The 16 or 14 would probably work better IMO.
I have a 14 on my crewcab, with the NV4500, and I like it. Runs a tad more boost on the HWY then I would like to see....but around town it's good. I drive fairly sedate though..
01-29-2016, 09:46 PM
#9
Registered User
Thread Starter
Thank you all for the replies.
I didn't mention it, but I do understand the trans will not live all the way through these mods. I'm thinking about a stronger auto but an NV4500 conversion with a south bend clutch seems like about the same money.
How big is would the difference be between my H1C turbo with a 16 cm^3 exhaust housing (like this: BD 16cm Exhaust housing) and the HX35 from a 2nd gen? Total power? Boost rate?
I'm finding plenty of "ran great off of a 200k mile 2nd gen" HX35s on ebay for $250-$400, lots of chinese Hx35 clones for $300 and a gamut of new HX35s from all sorts of weird applications with oddball inlet and exhaust fittings and small and large housings for $400-$1000. Looks like a real new Holset HX35 meant for a 2nd gen is around $1200. Are there any of the less expensive options that are wise buys or should I just bite the bullet and buy the real deal from the get go? Of course the turbo discussion is for when I get that far along...
I didn't mention it, but I do understand the trans will not live all the way through these mods. I'm thinking about a stronger auto but an NV4500 conversion with a south bend clutch seems like about the same money.
How big is would the difference be between my H1C turbo with a 16 cm^3 exhaust housing (like this: BD 16cm Exhaust housing) and the HX35 from a 2nd gen? Total power? Boost rate?
I'm finding plenty of "ran great off of a 200k mile 2nd gen" HX35s on ebay for $250-$400, lots of chinese Hx35 clones for $300 and a gamut of new HX35s from all sorts of weird applications with oddball inlet and exhaust fittings and small and large housings for $400-$1000. Looks like a real new Holset HX35 meant for a 2nd gen is around $1200. Are there any of the less expensive options that are wise buys or should I just bite the bullet and buy the real deal from the get go? Of course the turbo discussion is for when I get that far along...
01-30-2016, 12:44 AM
#10
Registered User
I would stay away from any knock off turbo's. Buy a gennie HX35, or Holset turbo/cartridge, and if it needs a rebuild, buy the bearing and service kit right from cummins....do not buy the off shoe kits for $50 or less off e-bay. I did, and it ruined my HX35. 
The BD 16cm housing would work fine, and is a good product. But it won't spool all that much quicker then the 18 that you have now...but might be enough to make you happy with an auto?
I'm thinking of getting the 16cm just to try. I like my 14, but the Hwy cruising I'm sitting around 4-5 psi. For best fuel economy you would want to see less then 5 psi boost while cruising....1-2 is best.
The BD 16cm housing would work fine, and is a good product. But it won't spool all that much quicker then the 18 that you have now...but might be enough to make you happy with an auto?
I'm thinking of getting the 16cm just to try. I like my 14, but the Hwy cruising I'm sitting around 4-5 psi. For best fuel economy you would want to see less then 5 psi boost while cruising....1-2 is best.
01-30-2016, 05:23 PM
#11
Registered User
5psi boost is ok. I would get 20.5mpg in the ford in my sig running 3-5psi out of the aurora4000. There were a lot of other differences than what is shown in my sig though (stock head, 181/210 cam, stock pistons, 5x16 injectors)
There's a lot that goes in to achieving good mpg
As for me, I wouldn't be concerned with the 12cm housing on an hx35. At 300hp and the rpm the VE is happiest at, I really don't think the housing is going to be a problem.
I would definitely recommend an hx35 or wh1c to hit your goal, and it should keep things cool enough for towing.
As for 300hp this is what I would do
4" exhaust
hx35 or wh1c
Adjustable boost elbow for the turbo (set the wastegate at 38psi if it wants to make more pressure than that)
THD fuel pin, 3200rpm spring and low pressure lift pump upgrade
gauges, obviously
5x12 injectors
Tune the fuel screw only mildly (to your liking), not to runaway. With 5x12s you should only have to give a turn or 2 on the fuel screw to get to 300hp. The nice thing here is with the injectors, it leaves a little on the table to grow if you decide you want more power
The injectors will still run as clean as stock, and may even run cleaner because with 237k miles on the stock injectors, they're going to be popping WAY low. probably below 200 bar
open up that intake like you mentioned.
Fix your KDP and skip the IP gear a tooth and pull the IP away from the head.
Do that, and you'll really like it, I just about guarantee it.
That's just about exactly what I'm going to be doing with the motor sitting in my garage (which is going in the ford, and the motor in the ford in my sig, is going to be set aside for another project) because I have the same goals as you with the motor
There's a lot that goes in to achieving good mpg
As for me, I wouldn't be concerned with the 12cm housing on an hx35. At 300hp and the rpm the VE is happiest at, I really don't think the housing is going to be a problem.
I would definitely recommend an hx35 or wh1c to hit your goal, and it should keep things cool enough for towing.
As for 300hp this is what I would do
4" exhaust
hx35 or wh1c
Adjustable boost elbow for the turbo (set the wastegate at 38psi if it wants to make more pressure than that)
THD fuel pin, 3200rpm spring and low pressure lift pump upgrade
gauges, obviously
5x12 injectors
Tune the fuel screw only mildly (to your liking), not to runaway. With 5x12s you should only have to give a turn or 2 on the fuel screw to get to 300hp. The nice thing here is with the injectors, it leaves a little on the table to grow if you decide you want more power
The injectors will still run as clean as stock, and may even run cleaner because with 237k miles on the stock injectors, they're going to be popping WAY low. probably below 200 bar
open up that intake like you mentioned.
Fix your KDP and skip the IP gear a tooth and pull the IP away from the head.
Do that, and you'll really like it, I just about guarantee it.
That's just about exactly what I'm going to be doing with the motor sitting in my garage (which is going in the ford, and the motor in the ford in my sig, is going to be set aside for another project) because I have the same goals as you with the motor
01-30-2016, 11:05 PM
#12
Registered User
Thread Starter
Thanks again for the replies.
I'm pretty sure my H1C has the 21cm^3 exhaust housing. It really has to rev to get boost.
I think I'll skip trying to make my H1C better and find an HX35. If I wanted a new one, where would be a good place to get one?
Rick, the list you posted looks good to me. I think I would save the injectors for last. I am not getting any smoke now so I wonder if my injectors have been rebuilt/re shimmed at some point in my trucks life. I've driven a few diesels with worn out injectors and this truck doesn't have any of those symptoms. They were IDI GM diesels, so maybe I can't compare, but they started hard and were generally just even more slugish than when the injectors were fresh.
What angles and what about SAC vs VCO for the injectors? Is THD a good source for these too? DDP is close enough to me that I could go there, any good or bad experiences?
I have a read a bunch of people skipping a tooth in the injector pump timing, but I though they generally pushed the pump towards the head, you recommend away from the head. Is that like skipping half a tooth from stock?
I'm pretty sure my H1C has the 21cm^3 exhaust housing. It really has to rev to get boost.
I think I'll skip trying to make my H1C better and find an HX35. If I wanted a new one, where would be a good place to get one?
Rick, the list you posted looks good to me. I think I would save the injectors for last. I am not getting any smoke now so I wonder if my injectors have been rebuilt/re shimmed at some point in my trucks life. I've driven a few diesels with worn out injectors and this truck doesn't have any of those symptoms. They were IDI GM diesels, so maybe I can't compare, but they started hard and were generally just even more slugish than when the injectors were fresh.
What angles and what about SAC vs VCO for the injectors? Is THD a good source for these too? DDP is close enough to me that I could go there, any good or bad experiences?
I have a read a bunch of people skipping a tooth in the injector pump timing, but I though they generally pushed the pump towards the head, you recommend away from the head. Is that like skipping half a tooth from stock?
01-31-2016, 11:16 AM
#13
Registered User
I would skip the HX35 as well and go to an HE351CW off of an '04.5 - '07 5.9 common rail.
You are definitely going to want to beef up your transmission as well. Maybe even look into converting your transmission to a lock-up converter while you're at it.
You are definitely going to want to beef up your transmission as well. Maybe even look into converting your transmission to a lock-up converter while you're at it.
01-31-2016, 12:16 PM
#14
Banned
i second the he351cw suggestion. although prepare for your mileage to suffer a little bit on the highway. you'll probably be better off than I am since you have an auto with more overdrive than my manual. i run around 7 psi boost at 65 mph. i still get 18.5 or so on the highway, but I was getting 20 pretty steady with my H1C/12cm exhaust housing combo. for around $100 and no fabricating, swapping the 12cm housing onto your H1C is a great improvement, especially if you have a good H1C and plan on staying with stock injectors. beyond that, you're going to want the he351cw. much bigger compressor
01-31-2016, 01:28 PM
#15
Registered User
i second the he351cw suggestion. although prepare for your mileage to suffer a little bit on the highway. you'll probably be better off than I am since you have an auto with more overdrive than my manual. i run around 7 psi boost at 65 mph. i still get 18.5 or so on the highway, but I was getting 20 pretty steady with my H1C/12cm exhaust housing combo. for around $100 and no fabricating, swapping the 12cm housing onto your H1C is a great improvement, especially if you have a good H1C and plan on staying with stock injectors. beyond that, you're going to want the he351cw. much bigger compressor
I'm going to call BS on the turbo alone making that much difference.