Powertrain swap with something later model

Todd,
When I went to buy a reman, I asked how they did a build book - Crickets......
If I had had a build book for this engine, I would have only had to buy one piston. That would have been a lot simpler of a recovery.
Matt
 
Hi Mr. RK Burns; I liked your post about the Howell TBI injection system. I’m going to look at a 1978 Royale w/ 403 engine.
I’m curious of the cost to do this? Also, did you have to change to the aluminum 65 gal gas tank I saw on a Jim Bounds video?
 
Hi Mr. RK Burns; I liked your post about the Howell TBI injection system. I’m going to look at a 1978 Royale w/ 403 engine.
I’m curious of the cost to do this? Also, did you have to change to the aluminum 65 gal gas tank I saw on a Jim Bounds video?
A lot of owners had installed the Howell TBI kit for the GMC Motorhome and had no problems, they ran great. However when I purchased my kit, Holley had just changed the injectors from 80 Pounds per Hour (pph) to 63pph. This caused some drivability issues such as stumbling whenever Acceleration Enrichment was called for. The fix was to increase the fuel pressure, but the Holley pressure regulator could not go high enough and still have stable regulation. The programmability of the EBL compensated for this, but eventually I changed to a Rochester TB from a 454.

I believe the Holley TB from Howell still has the smaller injectors and I believe Rance uses the Rochester TB with the larger injectors. That's why I suggested going with Rance. I would check out the injector sizes from both to be sure. Rance does not sell the EBL upgrade, at least it is not mentioned on their website. You can still get it direct from DynamicEFI.com

Applied GMC sells the Howell kit with the EBL and Electronic Spark Advance distributor for $2,349.

I'm still running the OEM fuel tanks and have no plans to change. I run on the top half of the fuel tanks. So I drive for 200-250 miles (about 1/2 tank). Thats about 4-5 hours, then I need to stretch and have a pee! Sure I'm driving around carrying 25 extra gallons of gas worth about $80. But any fix for that is going to cost way more than $80, and I'll still need to stop every 200-250 miles. I've heard a lot of people with Jim's tank are not too happy with them.
 
  • Like
Reactions: Glen Even
Back in about 1990 we put a 5.9 Cummins with a 4L80e trans with a Gear Venders overdrive in a 1984 GMC 3500 dually pickup. The 4L80e was a new trans at the time and using the GV let us split gears and provide 8 forward gears. It was a real road runner empty but towing with a gross of 20,000 proved troublesome. After destroying two tranny's Chevy said enough and the third trans would be their last freebie. We finally figured out that the constant hammering of the diesel at the lower engine speeds under load was killing the trans. Learning to NOT use overdrive in high gear solved the problem and all lived for another 300,000 miles.
As for engine swaps, my 6.5 TD Inter cooled 4L80e driven 1977 Royale has worked very well for us, although not a project for the faint of heart.
Hal
Wouldn't a more massive flywheel dampen the pounding diesel effect?

RickMike
 
Wouldn't a more massive flywheel dampen the pounding diesel effect?

RickMike
Rick,
Not Really.

When you add that much mass to the flywheel, you create a whole brand new set of problems that still need to be fixed before that powerplant is commercial.

When at Chrysler (while they were still Chrysler), I did a lot with that engine and in the turbo-version, the torque pulses are just so high that they could rip the blades out of the converter. We actually had to work the engine's program to de-power at lower speeds.

Matt_C
 
Wouldn't a more massive flywheel dampen the pounding diesel effect?

RickMike

Unfortunately, although that's a great engine, it's weighs way too much to put on the already full loaded front end of the GMC motorhome. And it's a deep skirt block, getting the TH425 driveshaft to pass underneath it is not trivial.

I'm waiting for someone to put a World Products Motown LS-Hybrid block into a GMC motorhome. The adaptation of the small (or big) block chevy to the TH425 has been proven, and the top end of the motor would be all modern Lx parts. Great flowing heads, MPFI, coil near spark ignition. Much of the build could be sourced from any pick-a-part yard for very low dollars. Almost all the cost would be in the short block.

Build it from 350 to 427 cubic inches , however big you want to go. I believe there is a combo that gets you very close to the original 403 block bore and stroke since that is known to be a good combination.
 
whenever I think I spent too much time and $$ on my engine rebuild and/or my EFI conversion threads like this come up. "just buy a World engineering block" Yeah, no, the block alone cost more than my rebuild and EFI system put together.
Anyone buying a block like that, or a diesel and then talks about fuel economy is really bad at math!
 
  • Haha
  • Like
Reactions: eserv and tmsnyder
Bruce, Good points. I have the GM TBI on my 91 Winne and it works great. that I'm sure would be a nice simple update instead of the carb. Its pretty much a stand alone system and can be adapted anywhere.
Steve, sorry for the zombie thread. I just scored the complete tbi for a 454 w/distributor. According to seller it does spark control. Are you doing spark control?
 
Paul,
I added spark control maybe a year after I did the EFI. EFI makes the engine run like like a modern engine, but Spark Control (ESC) really wakes up the engine... more get up and go!.

I have the upgraded EBL Engine Control Module (ECM) which makes setup and tuning a snap... you can't really tune a OEM ECM.

FYI, you will likely need a ESC distributor for an Oldsmobile because they turn in the opposite direction. The gear, pickup coil and ignition are all different.
 
  • Like
Reactions: Paul Garnier
Paul,
I added spark control maybe a year after I did the EFI. EFI makes the engine run like like a modern engine, but Spark Control (ESC) really wakes up the engine... more get up and go!.

I have the upgraded EBL Engine Control Module (ECM) which makes setup and tuning a snap... you can't really tune a OEM ECM.

FYI, you will likely need a ESC distributor for an Oldsmobile because they turn in the opposite direction. The gear, pickup coil and ignition are all different.
So I'm staring at a complete 454 TBI efi (in a box) that had been retrofitted to an '81. I even have the distributor. I know I want spark control, but what's the missing link? My 76 Birchy is currently running with her OE HEI(?) dizzy. How did GM implement spark control without a knock sensor?
 
Last edited:
So I'm staring at a complete 454 TBI efi (in a box) that had been retrofitted to an '81. I even have the distributor. I know I want spark control, but what's the missing link? My 76 Birchy is currently running with her OE HEI(?) dizzy. How did GM implement spark control without a knock sensor?
You need a knock sensor and it's module to retard the spark in case of knock