Found my replacement engine!

[mountainkowboy]

Introducing the new 502" EFI crate combo. 581 TQ @ 3,200 436.5 HP @ 4,600.

This baby is READY TO WORK !!!

We've been wrestling around with the idea of replacing Red with something younger and I just don't see the need. I can put that money into her and get basically a brand new truck that will out pull any new gasser.....lol.

[Grit_dog]

bucky wrote:
Yes, that would be one of the earliest Allisons behind a DM. Allison trannys are one of the best if not the best in the industry. They are used in different configurations all over the world. The issue with the longevity in the early DMs was that GM speced the tranny to the stock power as the DM power numbers increased over the years. Tuning and hot rodding a 02 DM without the needed upgrades to the tranny will not end well. That's all I'm saying and that is why I suggested a straight drive (manual) trans behind that behemoth 502 in that older Ford truck.

But the 502 that the OP is planning on doesn't make any more torque than a LiLY Duramax.

[bucky]

Yes, that would be one of the earliest Allisons behind a DM. Allison trannys are one of the best if not the best in the industry. They are used in different configurations all over the world. The issue with the longevity in the early DMs was that GM speced the tranny to the stock power as the DM power numbers increased over the years. Tuning and hot rodding a 02 DM without the needed upgrades to the tranny will not end well. That's all I'm saying and that is why I suggested a straight drive (manual) trans behind that behemoth 502 in that older Ford truck.

[ramyankee]

bucky wrote:

Turtle n Peeps wrote:

bucky wrote:
A stock 1000 Allison won't last with those hp and torques numbers. Put a straight drive behind with a good clutch and have fun. YeeeeeHaaaaaaaaaaaw.
Bowtie in the back window optional.

Why is that when a stock DM HP numbers are higher than that gas engine and torque numbers are WAY higher?

Saw a lot of tuned Duramax trucks during my working years with blown Allison trannys that warranty would not cover. That 502 engine in a 90 Ford truck will not have the software to minimize the issue. I'm only referencing the light duty Allisons, not the models specifically designed and installed in behemoth MHs and newer model big number 2500 and 3500 pick ups. His application would require a tranny rework to last is all I'm saying.

Since I have a 2002 Allison I guess it would be considered a light duty tranny, yes?

[Grit_dog]

Bucky, your confused.

[bucky]

Turtle n Peeps wrote:

bucky wrote:
A stock 1000 Allison won't last with those hp and torques numbers. Put a straight drive behind with a good clutch and have fun. YeeeeeHaaaaaaaaaaaw.
Bowtie in the back window optional.

Why is that when a stock DM HP numbers are higher than that gas engine and torque numbers are WAY higher?

Saw a lot of tuned Duramax trucks during my working years with blown Allison trannys that warranty would not cover. That 502 engine in a 90 Ford truck will not have the software to minimize the issue. I'm only referencing the light duty Allisons, not the models specifically designed and installed in behemoth MHs and newer model big number 2500 and 3500 pick ups. His application would require a tranny rework to last is all I'm saying.

[BenK]

Hornet...very cool !

[FishOnOne]

Cummins12V98 wrote:
FISH too funny on the vid, this guy has a shop that works on there trucks. He is trying to get business!

The 6 speed is very rare for a second gen and they are considered the trans to have. FACT is the 5 speed that is common has the 5th gear nut issue but I bet everyone of them out there has had theirs repaired.

Sure some of these things can go wrong on any truck that's 18-28 years old!

Bottom line they hold their value better than the others of the same era for good reason.

It is funny... But I can understand why someone will pay big bucks to purchased on these refurbished trucks because of the engine and it's simplicity. I just don't know anyone or see these trucks on the road anymore.

[hornet28]

These are my hot rods. Although that 85 dually really hauled a&% I'm 76 yrs
41 Ford with 454

17 T with a Hemi and 4 spd

[BenK]

Hornet...understand and why still deciding...

Many are wants and deciding whether or not to which items will become a need... Currently, the 7.4L with about 170K miles still runs strong enough and is in good condition

Both OD's won't be on for towing and know in 1:1 with a 5.38 will really suck in MPG...my choice will be dictated by hot rod vs towing heavy. No longer own a trailer, nor boat. Just borrow from church members & buddies

A lot will depend how comfortable that I'm going to be able to NOT get into it while towing. Just turned 72, but still have that Boy Racer in me

Another option for me is to just build the Sub into my hot-rod truck and purchase something else to tow heavy with

Common sense might creep back into my picture and just build a solid 7.4L with upped compression and keep the 4.1's

Glad the OP posted this...fits so many of us out there.

[js9234]

I've seen plenty of them in Texas.

Grit dog wrote:

FishOnOne wrote:

Cummins12V98 wrote:
"If I were considering a radical swap like that I'd go for a built 12V B series Cummins, but that's just me."

Lots of people do that conversion, "FUMMINS"

I've yet to see one in the wild. As a matter of fact it's been many...many...years since I've seen a 12v.

Maybe Texans aren’t as resourceful...lol.
Plenty of guys re-purposing otherwise worthless Fords with 12Vs around here.

[colliehauler]

If I were going a new engine route in a dedicated tow vehicle I would get one built with lots of low end grunt. Thats where it would spend the majority of time running in that RPM range.

[hornet28]

BenK wrote:
Similar situation with my Suburban


Looked at that GM 502 crate engine and decided to rebuild the 7.4L

Passing CA smog a must and no one have an acceptable answer on the 502

So my 7.4L is looking to have a 280 cam, roller rockers, 9.x compression, worked head, marched injectors, etc to be a bit under 500 ft/lbs around 2-2.5 KRPMs, etc

Built 4L80E rated 1KHP

Gearvenders with the splitter option, 0.5 OD, which will turn the 4 speed into an 8 speed

5.38 diffs, but having a tough time finding it for the front

That will give a lower 1st and higher OD

Don't know if the Xfrcase will need beefing up

1996 K3500 Sub and fits/suits me

Either LT255/85R16 or LT285/75R16 on current 10" wide alloys. Not going to lift...maybe a torsion bar crank

Still deciding...

Are you building this for towing? If so aren't you getting a bit high on the cam for down low grunt? You do realize that towing in OD isn't recommended even by Gear Vendor. Something you might think about is using factory style rockers. Why? Because if you are running some long distances how available do you think a replacement roller rocker is going to be in Timbuktu. That was advice I received from a very well know engine builder when I built a 454 stroker for an 85 GMC CC dually I was towing with then. It was 489", 4 spd, Gear Vendor, 4.56 geared had plenty of power but could really suck the gas. Never got above 11 mpg empty and made it into the 5's loaded in the mountains in the west. That cinched it for me buying my first diesel

[mountainkowboy]

time2roll wrote:
https://www.chevrolet.com/performance/crate-engines/big-block-ram-jet-502

There aint no way a GM engine is goin in my Furd. this is a built 460 engine that will bolt in like it was born there

[mountainkowboy]

BenK wrote:
Similar situation with my Suburban


Looked at that GM 502 crate engine and decided to rebuild the 7.4L

Passing CA smog a must and no one have an acceptable answer on the 502

So my 7.4L is looking to have a 280 cam, roller rockers, 9.x compression, worked head, marched injectors, etc to be a bit under 500 ft/lbs around 2-2.5 KRPMs, etc

Built 4L80E rated 1KHP

Gearvenders with the splitter option, 0.5 OD, which will turn the 4 speed into an 8 speed

5.38 diffs, but having a tough time finding it for the front

That will give a lower 1st and higher OD

Don't know if the Xfrcase will need beefing up

1996 K3500 Sub and fits/suits me

Either LT255/85R16 or LT285/75R16 on current 10" wide alloys. Not going to lift...maybe a torsion bar crank

Still deciding...

One thing I don't have to worry about is smog, not tested in rural Oregon.