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mikeyj350 · 07-31-2018, 10:46 AM

So the 350 TBI was running great, but as we all know they aren't exactly the most powerful V8's around in stock form. That became especially apparent when I bought and dragged home a 34' 10,800lb travel trailer from about 2 hours away! It's time for Belle to get a bump in oomph.

Over the years I've built a few engines for myself and a couple other friends, mostly 350's but one 454 and a couple other oddball engines too. For this build, I wanted to do a 383 TBI stroker, retaining a stock appearance but with as much torque and "sleeper" power as I can fit in there.

Additionally, although the 4L80E is a great transmission, the stock first-year '91 model could arguably benefit the most from a refresh and a few upgrades. Mine was performing and shifting perfectly, especially after installing the Transgo HD2 kit, but I wanted to have the peace of mind with the new engine, and also learn how to do my first-ever transmission overhaul.

So, I shopped around and found a first-run '90 Goodwrench 350 core and a '93 4L80E core for $100 each. The idea was, I wanted to keep the original engine and tranny untouched (at least for now) and build up both while I continued to drive the truck as-is. Both ended up being great finds, as they were indeed first-runs and workable cores.

A quick rundown of machine work and component selections that went into the engine build:

-Block bored 0.030" & decked 9.015"
-New Chevrolet Performance Vortec heads, worked over with 3-angle valve job, lift clearanced, pushrod clearanced, Z28 springs, resurfaced
-Eagle 383 rotating assy, balanced, 9.4:1 compression
-COMP Hydraulic roller 206/210 @ 0.050 w/ new OE lifters/chain
-1.6 roller rockers give 0.489"/0.489" lift
-Performer RPM Air Gap w/ TBI adapter plate
-5.7 TBI unit bored to 50mm, flow-matched injectors, injector spacer and bumped-up line pressure
-PCM reprogram using TunerPro and APU1 emulator/programmer/datalogger with MSD wideband O2 sensor
-Hedman Black Maxx headers
-Hooker Max Flow mufflers w/ new 2.5" dual exhaust
-Front accessory brackets of 98 vortec 5.7 truck motor

All dressed up before install

Old 350 coming out with my fiancee/helper Sarah striking a pose for the camera

Video of the first start here (sorry it's sideways)

This may have been the first time I had a first start where the engine fired up right away on the first try!!

A couple minor snags, one was I forgot to hook the tach wire up so Sarah couldn't target the 1500-2000rpm we were going for to break in the cam, and the AC compressor clutch started dragging and began to smoke. Minor stuff, and we got it all resolved quickly.

Tuning the engine using Tunerpro and the APU1 programmer was definitely a trip, I'll save all the details on that for a future post. Suffice to say, it's running great now after a lot of trial and error. I still think I can improve the timing curves to gain a bit more power, but it's "fine" for now.... enough is enough sometimes!!!

For the transmission, I consulted with Jake's Performance and ended up with their "Stage 2" overhaul kit. Tearing my core down, there was definitely a moment of "what the f--- did I get myself into??!?" There are A LOT of parts inside this beast:

The 4L80E core all torn apart, parts labeled and organized as best as I could

Then, after many weeks of careful inspection, cleaning, parts replacement, and reassembly, I somehow ended up with everything back together!

The complete rebuilt 4L80E transmission, ready to install

After the engine was in and running acceptably, it was time to install the transmission. While the rest of the drivetrain was apart, I decided to also grab an overhaul kit for the NP205 from ORD and give it a cleaning and refresh as well. This was my first time rebuilding a transfer case also, and although it was a bit tricky in parts, it definitely pales in comparison with the tranny I had just finished! So it seemed easy by comparison.

Somehow I never took a pic of the transfer case until the overhaul was finished, so here it is already installed back in the truck

Once all was back together, I was SUPER nervous that something hadn't been done right. Fired her up on jack stands, topped off the tranny fluid, and put her in gear. What do you know, the wheels started spinning.... even in the right direction!!!!

So, the engine and drivetrain refresh has been a success. Good thing too, because Belle had more than one mission waiting for her in the immediate future. The saga continues for the next update...

07-31-2018, 10:46 AM	#19
mikeyj350 Registered User Join Date: Oct 2017 Location: Marion, IA Posts: 12	Update 2 - Engine and drivetrain So the 350 TBI was running great, but as we all know they aren't exactly the most powerful V8's around in stock form. That became especially apparent when I bought and dragged home a 34' 10,800lb travel trailer from about 2 hours away! It's time for Belle to get a bump in oomph. Over the years I've built a few engines for myself and a couple other friends, mostly 350's but one 454 and a couple other oddball engines too. For this build, I wanted to do a 383 TBI stroker, retaining a stock appearance but with as much torque and "sleeper" power as I can fit in there. Additionally, although the 4L80E is a great transmission, the stock first-year '91 model could arguably benefit the most from a refresh and a few upgrades. Mine was performing and shifting perfectly, especially after installing the Transgo HD2 kit, but I wanted to have the peace of mind with the new engine, and also learn how to do my first-ever transmission overhaul. So, I shopped around and found a first-run '90 Goodwrench 350 core and a '93 4L80E core for $100 each. The idea was, I wanted to keep the original engine and tranny untouched (at least for now) and build up both while I continued to drive the truck as-is. Both ended up being great finds, as they were indeed first-runs and workable cores. A quick rundown of machine work and component selections that went into the engine build: -Block bored 0.030" & decked 9.015" -New Chevrolet Performance Vortec heads, worked over with 3-angle valve job, lift clearanced, pushrod clearanced, Z28 springs, resurfaced -Eagle 383 rotating assy, balanced, 9.4:1 compression -COMP Hydraulic roller 206/210 @ 0.050 w/ new OE lifters/chain -1.6 roller rockers give 0.489"/0.489" lift -Performer RPM Air Gap w/ TBI adapter plate -5.7 TBI unit bored to 50mm, flow-matched injectors, injector spacer and bumped-up line pressure -PCM reprogram using TunerPro and APU1 emulator/programmer/datalogger with MSD wideband O2 sensor -Hedman Black Maxx headers -Hooker Max Flow mufflers w/ new 2.5" dual exhaust -Front accessory brackets of 98 vortec 5.7 truck motor All dressed up before install Old 350 coming out with my fiancee/helper Sarah striking a pose for the camera Video of the first start here (sorry it's sideways) This may have been the first time I had a first start where the engine fired up right away on the first try!! A couple minor snags, one was I forgot to hook the tach wire up so Sarah couldn't target the 1500-2000rpm we were going for to break in the cam, and the AC compressor clutch started dragging and began to smoke. Minor stuff, and we got it all resolved quickly. Tuning the engine using Tunerpro and the APU1 programmer was definitely a trip, I'll save all the details on that for a future post. Suffice to say, it's running great now after a lot of trial and error. I still think I can improve the timing curves to gain a bit more power, but it's "fine" for now.... enough is enough sometimes!!! For the transmission, I consulted with Jake's Performance and ended up with their "Stage 2" overhaul kit. Tearing my core down, there was definitely a moment of "what the f--- did I get myself into??!?" There are A LOT of parts inside this beast: The 4L80E core all torn apart, parts labeled and organized as best as I could Then, after many weeks of careful inspection, cleaning, parts replacement, and reassembly, I somehow ended up with everything back together! The complete rebuilt 4L80E transmission, ready to install After the engine was in and running acceptably, it was time to install the transmission. While the rest of the drivetrain was apart, I decided to also grab an overhaul kit for the NP205 from ORD and give it a cleaning and refresh as well. This was my first time rebuilding a transfer case also, and although it was a bit tricky in parts, it definitely pales in comparison with the tranny I had just finished! So it seemed easy by comparison. Somehow I never took a pic of the transfer case until the overhaul was finished, so here it is already installed back in the truck Once all was back together, I was SUPER nervous that something hadn't been done right. Fired her up on jack stands, topped off the tranny fluid, and put her in gear. What do you know, the wheels started spinning.... even in the right direction!!!! So, the engine and drivetrain refresh has been a success. Good thing too, because Belle had more than one mission waiting for her in the immediate future. The saga continues for the next update... __________________ Mikey J. 1991 V3500 Crew "Belle" - the new project! (like I need any more)