Daveinet wrote: The ECM is counting on a transmission, so you will have to have a 4L80E. You may be able to find someone to reprogram the ECM to ignore the trans, but it will still need a speed sensor.
The 8.1 PCM is programmed to work with the Allison trans computer, I would stick with that. It is a lot better trans than a 4L80E, probably close to a wash price wise if you consider reprogramming the 8.1 PCM, the 4L80E and how you will control that, it is an electronic trans.
I assumed he would get the motor from a totaled pick up, not another motorhome. While I certainly agree the Allison would be a better choice, it may not swap in as easy. As I recall, the Allison is much bigger in the mid-section and may not fit under the floor. I know the Allison will not fit in my coach, but the 4L80E does. You can get either ECM. Sure if the Allison will fit, then go for it. Unfortunately, we don't know what coach he has.
Dave
FMCA F298817
'83 Revcon Prince 31' FWD
502 w/Howell/Edelbrock MPFI, Thorley's & Magnaflows,
Koni FSD, Class A built for gear heads ?????? Revconeers Forum
There is nothing compassionate about taking someone elses money and giving to the poor.
They also make aftermarket stand alone EFI that you can get to control any Factory engine and or trans. So if EFI is your answer, you can get a system and not have to try to piece part a system together. Find the engine you want, trans, and buy the system to control everything.
Thanks everyone for your input. Really appreciate hearing from those who have made the change. I have a 1986 Beaver Continental, w/ a Chevy 454 on a P30 chassis. The 454 is in excellent condition but have been dreaming about making the change to the Workhorse.
I understand those who have suggested a new coach. We really like the lay-out of the Beaver and it has all the bells & whistles that we love, so plan to keep it indefinitely.
Len
You have to ask, what are your priorities? Don't answer "new technology" That is the wrong answer. Is it power, reliability, mileage? On a scale of 1 to 5, how do you rate these priorities?
You have to weigh cost and effort over benefit. I'm assuming your main issue is power, as a coach as heavy as a Beaver on a gas chassis has to be pretty sluggish. For around $2500, you could install and Edelbrock MPFI and headers. That would certainly gain a significant amount of power. Technically you can put Vortec fast burn heads on it, but that gets a little tricky. You have to block off some water passages, and use a special intake manifold, but it can be done. Edelbrock makes some fast burn heads for the old engine, but they are not labeled as such.
BTW:If you think you can justify the cost by saving in mileage, its not going to happen in your lifetime.
LHowells wrote: Thanks everyone for your input. Really appreciate hearing from those who have made the change. I have a 1986 Beaver Continental, w/ a Chevy 454 on a P30 chassis. The 454 is in excellent condition but have been dreaming about making the change to the Workhorse.
Len, Now we have something to work with......You have a 235 HP (454) MK4 along with a "Peanut ported heads" which ain't all that bad.....
IF your block is in great shape you can bore it 0.60 over and toss in a 1/4 stroker crank and have a "496" torque monster, "Cam"..Original is 193 intake and 203 exhaust at the 050 mark point...For the increased torque of the bore & stroke and 206/213 cam will fill your cylinders and keep the mileage also....
A good valve job would allow you to keep those heads or step up to some L29 heads BUT you might lose some low end grunt, Depending on how far down the pistons are (usually 25 thou) have the block decked to zero and use a standard gasket or so quench area (40 thou) which will really eliminate pinging and detonation.
With the deck shaved down to piston height and the head/heads you and you machinist determine (CCs) your compression will be bumped up by 1/2 point at least and you can run the cheaper fuel depending on the ignition setup....My setup requires 91 octane in the summer heat and 89 in the cooler weather.
Since you also have a 3 speed (TH400 trannie) you are no doubt cruising down the super slab around 3,000 RPM at 60 MPH, I have installed a very tight torque convertor and expected a 250 RPM drop but only got a 125 drop @ 60 MPH and a 30-50 drop at idle (depending on the weather.....You living in Virginia are very close to the TOP machine shop on the east coast (Maryland) so enjoy a good rebuild...You should have a 425 HP torque monster with excellant fuel mileage....
if youre thinking about the whole take out-install (ADAPT!) A different engine... why not go with diesel (14-16MPG YUMMMMMM!) my proyect is for a Southwind 454, now going to a ford Navistar Te-444 w/allison 5 speed close ratio tranny (no computer).
complications: had to adapt a throttle by wire engine (I should have goen with a mechanical cummins 5.9). had to change the rear end ratio. had to work-manage over my tan carpet w/a diesel engine-oils etc....
regrets: if you do this "overhauling" DO NOT expect some return in payment or cost-benefit TO BE REACHED youre doing this for Y*O*U*R*****O*W*N****P*L*E*A*S*U*R*E**, you will not receive what you pay when you resale.... let your heirs worry abouth that.....ENJOY THE EXPERIMENT!!!!!!whichever route you take!
my wishes to you GO AHEAD!!!!!!
I I HAVE A DATE WITH ETERNITY, AND I DON´T WANT TO BE LATE!
BULLETLS1 wrote: if youre thinking about the whole take out-install (ADAPT!) A different engine... why not go with diesel (14-16MPG YUMMMMMM!) my proyect is for a Southwind 454, now going to a ford Navistar Te-444 w/allison 5 speed close ratio tranny (no computer).
complications: had to adapt a throttle by wire engine (I should have goen with a mechanical cummins 5.9). had to change the rear end ratio. had to work-manage over my tan carpet w/a diesel engine-oils etc....
regrets: if you do this "overhauling" DO NOT expect some return in payment or cost-benefit TO BE REACHED youre doing this for Y*O*U*R*****O*W*N****P*L*E*A*S*U*R*E**, you will not receive what you pay when you resale.... let your heirs worry abouth that.....ENJOY THE EXPERIMENT!!!!!!whichever route you take!
my wishes to you GO AHEAD!!!!!!
Why not the 3.9L/4B. I know it does not quite have the torque, but gets good fuel mileage and would get the job done, plus it bolts right up to the GM tranny.
BulletLS1 is so right, make the change only if you will enjoy the work. I'm putting a 2006 8.1 that I bought from Work Horse in late 2007. It was used for heat test in there, then experimental rear engine chassic and had 7,200 miles. I got engine, all sensors except 02 and MAF for less than $1550.00 and bought a new 2007 4L80E for $1500.00. I will have spent that much again on wiring, (Speartech) and modifacations to install the engine and transmission in my Revcon. I have tried to keep it all GM so anyone can work on it. I started on it the week of Thanks Giving 2008 and would have it running by now except I rebuilt the front suspension, put in a 2007 chevy truck dash, a 2004 steering column and am rewiring the rest of the coach. For now I'm using a inline fuel pump, but plain on going to in tank pumps and GM gage units. Original engine was a carb 454 and transmission was TH 475 (400). Rated HP was 215 @ 3,400 RPM and torque 332 ft. lbs. @ 3,400 RPM. The 8.1 is rated at about 340 HP and 480 ft lbs., or there about. I will end up with a finial drive of 3.15 to 1 with a lock-up converter, before it was 3.35 to 1 and no lock-up. I have learn a lot and would I do it again, ask me later.
2500 suburbans and 2500 savana/express full size vans come the 8.1 and 4L80/85E trans. this might be another source of parts. the 4l trans and 8.1 combo can be tuned with EFI live and many other tuners, I use Black bear performance tune on My 2500HD.
if I had a choice I would use the allison trans. not the 4L80.
2003 GMC 2500HD ccsb DURAMAX Allison 3.73 ratio 285/75/16
2000 Wilderness 34 5L 3 slides 36 ft
statements in this post should be considered opinions and not facts
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