1 2
m4ff3w
m4ff3w UberDork
7/12/18 3:20 p.m.

So I may have accidentally bought a 12000lb vehicle with a 455 Olds Toronado drivetrain...  It's been sitting for a number of years (decade and a half?) and the carb is likely varnished to hell and back..

So I'm thinking of TBI efi.  Maybe a TBI from a 454?  Early 90s Top Kick/Kodiak?

 

What say yall?  

Oh, I do still have a MS2, if that might be better than early 90s GM technology for fuel+spark.  This isn't something I'd plan on getting dyno-tuned though.  Either stock GM stuff or MS+wideband.

Stefan
Stefan MegaDork
7/12/18 3:37 p.m.

I'd vote GM TBI conversion as a first step since you'll have to sort out the fuel system and the electrical, so having a RTR solution is probably closer to ideal.

The MS2 would allow better tuning for mileage and power, but would control the GM TBI hardware just fine and could be a stepping stone after the GM parts are up and running.

MS2 plus an intake like this, modified for injectors, would be a good further step if you wanted to improve things a little more: 

http://www.cpperformance.com/p-13585-satin-crosswind-455-olds-intake-manifold.aspx

Dyno tuning isn't needed for general tuning, just for fine tuning.

m4ff3w
m4ff3w UberDork
7/12/18 4:01 p.m.

In reply to Stefan :

I like the way you think and that manifold is really awesome, especially for the price.  

However, on second look, I think that is way too high to fit under the engine cover.  Sadness ensues.  

Dusterbd13
Dusterbd13 MegaDork
7/12/18 4:21 p.m.

Honestly, unless you are really well versed in megasquirt or prom burning, id grab a fitech self learning ajd a tanks inc pa4. If i had it to do over, thats what i would do. 

Hell, im giving the megasquirt one more try before it hits the dumpster in exchange for a fitech.

Vigo
Vigo UltimaDork
7/12/18 4:32 p.m.

MS2 is honestly preferable to piecing together a GM ecu setup even if all it does is fuel control on a stock TBI unit. You can just stab a cheapie HEI distrib in it for ~$100 and do fuel only and with a stock engine it will be completely fine. TBI should just need a Tach out signal from distrib since it doesn't care about crank position and all the spark duties will be handled by the HEI with one-wire input. It'll be dead simple but still tunable. 

Stefan
Stefan MegaDork
7/12/18 4:53 p.m.

You could always replace the 455 with a modern 454 or similar and use an off the shelf EFI harness and solution.

Duster, your MS problems are weird and related to the collection of parts used in your build. 

The OP likely won't have the same problems.

MotorsportsGordon
MotorsportsGordon Reader
7/12/18 5:21 p.m.

If your going to add tbi to the 455 your probably best off going with a brand new aftermarket tbi. Companies like Holley,msd,etc all make them.

stuart in mn
stuart in mn UltimaDork
7/12/18 6:05 p.m.
Stefan said:

You could always replace the 455 with a modern 454 or similar and use an off the shelf EFI harness and solution.

A modern GM/Chevy 454 isn't readily interchangeable with an Olds 455, they have different bolt patterns for the transmission.

I'd say as a first step get a rebuild kit for the carburetor and get it running.  Then, you can deal with fuel injection later.  

A friend of mine did a MS conversion on a 455 Pontiac a few years back, it ran well but was a lot of work - you have to add injectors to the intake manifold, modify the gas tank, run new fuel lines, etc.

Stefan
Stefan MegaDork
7/12/18 6:15 p.m.

In reply to stuart in mn :

A conversion adapter is all that is needed.

Dusterbd13
Dusterbd13 MegaDork
7/12/18 6:33 p.m.

In reply to Stefan :

I wish you were closer and i could give you money to fix it. Wes is doing his best, but this thing is evil.

Op: please listen to these guys. They definately know more than me. But I'd still try to avoid ms. Gm stuff should be nearly drop in with 454 parts.

Trans_Maro
Trans_Maro PowerDork
7/12/18 6:59 p.m.

Actually, the Chevy engine is the red-headed stepchild of the GM line.

Every other brand shared a bellhousing, Chevy was the weird one.

Swapping a  454 onto a Toro transaxle will probably be more work than "just an adapter" I'd bet the motor mounts are quite a bit different and the oil pan will have issues at the very least.

AnthonyGS
AnthonyGS New Reader
7/13/18 12:13 a.m.

My extensive research in this area for a potential Miata V8 swap has me leaning to the Holley sniper setup.  Better tech support and less issues than fitech.  Way easy compared to any OEM system or MS.  

TIGMOTORSPORTS
TIGMOTORSPORTS Dork
7/13/18 5:03 a.m.

Sounds like you bought an old motorhome?

 

akylekoz
akylekoz Dork
7/13/18 5:22 a.m.

On a stock motor I never had any problems with a Q-jet, new or rebuilt ones are $2-400.  Is this the easy button?

ClemSparks
ClemSparks UltimaDork
7/13/18 6:39 a.m.

I was looking into TBI-where-TBI-doesn't-belong scenarios recently and stumbled across this thread that might be helpful to you depending on which direction you go:  Working a stock TBI harness for conversions.

mad_machine
mad_machine MegaDork
7/13/18 7:19 a.m.

engine cover, old torando drivetrain, 12000 pound weight... you bought a GMC motorhome, didn't you?

lrrs
lrrs HalfDork
7/13/18 7:27 a.m.
mad_machine said:

engine cover, old torando drivetrain, 12000 pound weight... you bought a GMC motorhome, didn't you?

Let's hope so.....and that there will be a build thread.  

noddaz
noddaz SuperDork
7/13/18 8:29 a.m.

Get it running on the carb first.  Then decide what you want to do.

m4ff3w
m4ff3w UberDork
7/13/18 8:44 a.m.
TIGMOTORSPORTS said:

Sounds like you bought an old motorhome?

 

Indeed.  1973 GMC

Dusterbd13
Dusterbd13 MegaDork
7/13/18 8:50 a.m.

That is abso-berkeleying-lutely AWESOME!!!!!

m4ff3w
m4ff3w UberDork
7/13/18 8:51 a.m.
ClemSparks said:

I was looking into TBI-where-TBI-doesn't-belong scenarios recently and stumbled across this thread that might be helpful to you depending on which direction you go:  Working a stock TBI harness for conversions.

Fantastic link, sir!

stuart in mn
stuart in mn UltimaDork
7/13/18 9:29 a.m.

A Quadrajet carburetor kit will cost about $40 from Summit or Jegs.  Figure in a bucket of carburetor cleaner and an afternoon in the garage, and then you're back on the road.

Don't forget that you'll have plenty of other recommissioning to do...cleaning out the gas tank, brakes, and so on.

accordionfolder
accordionfolder Dork
7/13/18 9:41 a.m.

Holy E36 M3 that thing is awesome.

ClemSparks
ClemSparks UltimaDork
7/13/18 1:08 p.m.
m4ff3w said:
ClemSparks said:

I was looking into TBI-where-TBI-doesn't-belong scenarios recently and stumbled across this thread that might be helpful to you depending on which direction you go:  Working a stock TBI harness for conversions.

Fantastic link, sir!

I know, right?  I think I subconsciously posted it here as much so I could find it again easily as to help you, lol ;)

californiamilleghia
californiamilleghia Reader
7/13/18 1:16 p.m.

Any pictures of one of those GMC motorhomes converted into a race car hauler ?

just wondering if there is a cool way to do the back doors / ramps

1 2
Our Preferred Partners
9Ez6mFmIUPegSr4Jf9gVnHynh4rcREd1cygUqfb2XWqMwQf3fiz8SZYp9lAEEpTt