The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - ’48 GMC Build – Cummins 4BT, 47RH, IFS, 4-Link, Air

reg3 · 04-20-2019, 02:10 PM

I picked up the engine a few days after bringing the truck home, donor truck was a 1994 Grumman box truck. The engine is a Cummins 4BTAA, 130 HP aftercooled variant (CPL: 1839). It had a little over 100k miles when I picked it up, ran pretty strong, had minimal blowby and wasn’t blowing too much smoke.

Build Plans for the engine:

Full rebuild, seals/bearings/gaskets, rotate oilpan (swap front pickup to rear pickup), KDP
ARP Head Studs, 60# valve springs, 4K GSK, DDP Stage 2 Injectors, Modified fuel plate, timing 16.5*
Modified 5.9/12V echaust header (cut and welded cylinders #1/#6) to make a center dump manifold

Turbo: this has been something I haven’t finalized yet. I initially thought about going with a HY35W off a 5.9/24V but I am moving now more towards a super HX30W (assy: 2835278).

Unfortunately during the teardown, I found that the head was cracked between the intake/exhaust valves on cylinder #3. So had to make a run up to my local Cummins parts distributor and pickup a new head (ouch). It wasn’t all bad news however, cylinder walls/pistons, main and rod bearings all looked almost brand new. I got it all buttoned back up and sprayed some fresh Cummins beige.

Pulled the engine using my 'specialized' orange cherry picker lol (Overkill is Underrated

)

04-20-2019, 02:10 PM	#3
reg3 Registered User Join Date: Feb 2015 Location: CT Posts: 30	Re: ’48 GMC Build – Cummins 4BT, 47RH, IFS, 4-Link, Air I picked up the engine a few days after bringing the truck home, donor truck was a 1994 Grumman box truck. The engine is a Cummins 4BTAA, 130 HP aftercooled variant (CPL: 1839). It had a little over 100k miles when I picked it up, ran pretty strong, had minimal blowby and wasn’t blowing too much smoke. Build Plans for the engine: Full rebuild, seals/bearings/gaskets, rotate oilpan (swap front pickup to rear pickup), KDP ARP Head Studs, 60# valve springs, 4K GSK, DDP Stage 2 Injectors, Modified fuel plate, timing 16.5* Modified 5.9/12V echaust header (cut and welded cylinders #1/#6) to make a center dump manifold Turbo: this has been something I haven’t finalized yet. I initially thought about going with a HY35W off a 5.9/24V but I am moving now more towards a super HX30W (assy: 2835278). Unfortunately during the teardown, I found that the head was cracked between the intake/exhaust valves on cylinder #3. So had to make a run up to my local Cummins parts distributor and pickup a new head (ouch). It wasn’t all bad news however, cylinder walls/pistons, main and rod bearings all looked almost brand new. I got it all buttoned back up and sprayed some fresh Cummins beige. Pulled the engine using my 'specialized' orange cherry picker lol (Overkill is Underrated )