Astro van cat conversion

[Snowy Rivers]

NOT MUCH CAT STUFF GOING ON....Raining a lot.....Computer took the big Chit.....Needed the OS updated.
Been running Zorin 0S9 and my apps were failing to open.

Updated to ZORIN OS16.2 (Linux box)

Finished it up this morning and it is running smoooooooooooooooth.

Had to add a cat theme to the screen......
60" TV screen....Really makes life easy on the eyes.....

 

[Snowy Rivers]

Wretched weather.....Sideways rain....Nothing going on outside.

Gonna move inside and clean up the shop and start getting ready to go after the 406 engine for the cat.....

Catching up on PRE WINTER stuff around the ranch has taken all my time since the rains started........

Lots of parts that were scavenged off the Vortec engine all stacked up on the work bench in a heap.....Up until now this was not any big issue.....

I need the space to get things ready to build an engine.......
I have enough new parts to get the short block well under way........
Finally made the choice for the cam shaft.....Going to go with the Comp cams XE268H
After the machinist and I beat over many scenarios and he called me to let me know that thew heads were indeed in good shape the plan came together.

Now it's time to start looking like we know what we're doing

 

[m1west]

Wretched weather.....Sideways rain....Nothing going on outside.

Gonna move inside and clean up the shop and start getting ready to go after the 406 engine for the cat.....

Catching up on PRE WINTER stuff around the ranch has taken all my time since the rains started........

Lots of parts that were scavenged off the Vortec engine all stacked up on the work bench in a heap.....Up until now this was not any big issue.....

I need the space to get things ready to build an engine.......
I have enough new parts to get the short block well under way........
Finally made the choice for the cam shaft.....Going to go with the Comp cams XE268H
After the machinist and I beat over many scenarios and he called me to let me know that thew heads were indeed in good shape the plan came together.

Now it's time to start looking like we know what we're doing

what is the duration@.050 and the lobe separation angle on the cam

 

[Snowy Rivers]

Here is the specs...
I have used one of these in the past in a 4x4 .....Was decent....With the really low gear ratio in the cat.....should be a decent cam..

With the 4oo plus inches in the engine this cam will not be real rumpy.....but will sound good and the RPM range that the cat will be using ( 2000/4500 ) it should put things in the sweet spot for the Vortec heads too..
The split duration is a good thing with the Vortec heads as well.
The lift is not excessive either


I have looked at a lot of grinds and ......Arrrrrgh...just waaay too many choices.....The bigger cubes should be a happy camper with this cam......The last one I used was in a 350 in a 4x4 with big rubber and not particularly deep gears......It was OK but .....Some much deeper gearing would have helped a lot.......

In the cat running at a reasonable 12 MPH will put the RPM at 3500 (3 speed auto tranny in direct drive)
4200 RPM will yield 14 MPH

I really do not see any reason to push the machine faster...
But a venture up to 5000 RPM could net 17 MPH
The gearing in the OC12 are 5.44 R&P and 2.44 drop boxes
Down in the business hole in the tranny should be quite sufficient to BREAK STUFF if one were to get stupid......
LOW gear in the tranny 2.52:1.....R&P 5.44:1.....DROP BOXES 2.44:1
LOW gear at 2000 RPM is about 2.7 MPH
Numbers based on zero slippage at the tracks....Just straight math....no dynamics in the mix
Converter slippage will certainly factor in.....The TH350 does not use a Lockup converter

Engine Family: Chevrolet 262-400 c.i. 8 Cylinder (1958-1998)
RPM Operating Range: 1,600-5,800
Grind Number: XE268H
Cam Type: Hydraulic Flat Tappet
Lifter Style: Hydraulic Flat Tappet
Camshaft Series: Xtreme Energy
Usage: Street/Performance
California Proposition 65: WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov
Advertised Intake Duration: 268
Advertised Exhaust Duration: 280
Intake Duration at .050 Inch Lift: 224 <..........................**********
Exhaust Duration at .050 Inch Lift: 230 <..........................**********
Intake Valve Lift: 0.477
Exhaust Valve Lift: 0.48
Lobe Lift Intake: 0.318
Lobe Lift Exhaust: 0.32
Lobe Separation: 110 <............................*********
Intake Centerline: 106
Exhaust Close ATDC: 27
Intake Open BTDC: 26
Exhaust Open BBDC: 72
Intake Close ABDC: 61
Camshaft Gear Attachment: 3-Bolt

Product Attachments

Recommended Components

 

[m1west]

Here is the specs...
I have used one of these in the past in a 4x4 .....Was decent....With the really low gear ratio in the cat.....should be a decent cam..

With the 4oo plus inches in the engine this cam will not be real rumpy.....but will sound good and the RPM range that the cat will be using ( 2000/4500 ) it should put things in the sweet spot for the Vortec heads too..
The split duration is a good thing with the Vortec heads as well.
The lift is not excessive either


I have looked at a lot of grinds and ......Arrrrrgh...just waaay too many choices.....The bigger cubes should be a happy camper with this cam......The last one I used was in a 350 in a 4x4 with big rubber and not particularly deep gears......It was OK but .....Some much deeper gearing would have helped a lot.......

In the cat running at a reasonable 12 MPH will put the RPM at 3500 (3 speed auto tranny in direct drive)
4200 RPM will yield 14 MPH

I really do not see any reason to push the machine faster...
But a venture up to 5000 RPM could net 17 MPH
The gearing in the OC12 are 5.44 R&P and 2.44 drop boxes
Down in the business hole in the tranny should be quite sufficient to BREAK STUFF if one were to get stupid......
LOW gear in the tranny 2.52:1.....R&P 5.44:1.....DROP BOXES 2.44:1
LOW gear at 2000 RPM is about 2.7 MPH
Numbers based on zero slippage at the tracks....Just straight math....no dynamics in the mix
Converter slippage will certainly factor in.....The TH350 does not use a Lockup converter

Engine Family: Chevrolet 262-400 c.i. 8 Cylinder (1958-1998)
RPM Operating Range: 1,600-5,800
Grind Number: XE268H
Cam Type: Hydraulic Flat Tappet
Lifter Style: Hydraulic Flat Tappet
Camshaft Series: Xtreme Energy
Usage: Street/Performance
California Proposition 65: WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov
Advertised Intake Duration: 268
Advertised Exhaust Duration: 280
Intake Duration at .050 Inch Lift: 224 <..........................**********
Exhaust Duration at .050 Inch Lift: 230 <..........................**********
Intake Valve Lift: 0.477
Exhaust Valve Lift: 0.48
Lobe Lift Intake: 0.318
Lobe Lift Exhaust: 0.32
Lobe Separation: 110 <............................*********
Intake Centerline: 106
Exhaust Close ATDC: 27
Intake Open BTDC: 26
Exhaust Open BBDC: 72
Intake Close ABDC: 61
Camshaft Gear Attachment: 3-Bolt

Product Attachments

Recommended Components

thats pretty close to the cam in my Magnum, only difference is mine is 118 on the intake. Heavy 73 power wagon with 1 ton running gear. It weighs over 7,000 pounds. Off road in low range it does well, on the street, until its hits 30 mph its a pig.

 

[m1west]

14 mph will feel like 100, the 603 I had was pretty sketchy at the top of 3rd gear.

 

[Snowy Rivers]

Yes 14 mph is cookin in a cat.......The track setup and the steering arrangement in these can be really spooky at speed...

A hydrostatic drive like the 3700 are far more predictable than the OC12 planetary steering......

I drove a 2100 for a few months one season at one of the ski resorts here......This was a stock 2100 V8 powered with the 14' blade and the drag out back......
12 mph balls to the wall.....Felt like you were flying.....Those 57" wide tracks whizzzzzing around right outside the door was a tad unnerving at times....Break a grouser and have it start beating on stuff was always good for MAX PUCKER.....

The low gears in the cat will allow the engine to get up on the step quickly ....so there should not be any "Piggy"

 

[m1west]

My experience with the 2 track is on a one lane steep switchback mountain road. Did most of it at 5 mph at times I stepped it up but always ended up scaring myself. Seemed like speed increase and steering action increased by square. Almost put it sideways doing about 25 down hill, steering got very touchy and over reactive at that speed. At 5 mph it was a workout. Honestly I am much happier with the mini track van.

 

[Snowy Rivers]

The big problem with the OC12 steering....OR THE OC4 ...or any other planetary type box.....The track on the side the turn is initiated towards SLOWS DOWN BY 1/3 and the opposite side speeds up by 1/3.........For slight turns/corrections at speed it acts more like a "Warp Speed Frog".....Nasty jerks instead of a steady/easy change in direction......

The 2100 being much heavier and usually packing a buttload of equipment and or shoving a blade....plus carrying the huge tracks was subject to severe steering band wear as compared to a Spryte or an Imp

The 2100 had/has hydraulic assist on the steering servos that assures the bands are locked to the drum whenever the steering is activated as opposed to the hand lever actuated master cylinder setup where the band pressure can be feathered and the resulting steering is not near as harsh.......

Hence the change to the hydrostatic steering (3700 cats) and others....All new stuff is hydro...

An easy steady drift can be initiated or a drastic change of up to and including running the tracks in opposite directions.

I have lamented over the steering on My cat A LOT
The final choice is nailed down to using air brake chambers operating two regular hydraulic brake master cylinders....

The full stroke of the master cylinder will be able to fully extend the steering slave cylinders on the OC12...

The choice on the design has been beat around for the last couple years......I had looked at using the hand lever setup like the Spryte.......The large tracks on the machine (Narrowed up to 44" from the original 57") are still big and heavy and will need firm action on the steering bands.....Too soft of an application will wear the bands rapidly.......

I looked at a new rendition of the original hydraulic setup .....but the parts needed to do it easily are not available....
The original steering control units are long since discontinued by the maker......

YESSSSSS...There were/are alternatives BUTTTTTTTTTTTTTTTTT....The cost got stupid expensive and were not an off the shelf item........

Using air over hydraulics was a simple way to go and all the parts needed are off the shelf.

The air is provided by a modified AC compressor (Jeep crowd has proven this adaptation quite dependable)
The master cylinders are again...off the shelf.......
The original slave cylinders on the OC12 are easy to get and the design is a proven one....And the parts are there on the box....

Air controls were an easy adaptation of two Big Rig trailer brake air valves (Trolly valve)
I grabbed a pair of Freightliner trailer valves.....

These allow bring the air pressure up gradually instead of BANG.......
The pressure needed is 65 psi to the air brake chamber to reach the needed 400 psi on the slaves
A regulated (65psi) source of air to the valves will allow the controls to be activated fully and reach optimal pressure at the bands...

There is the ability to "Feather" the pressure some for small steering corrections at speed ...hopefully without the ballistic Frog results....

All air lines and fittings are a standard nylon DOT air brake line... Quick release valves, relay valves, check valves.....All this stuff is off the shelf goodies that can be replaced easily and readily sourced at NAPA or many on line sellers

Air tanks are standard sized big rig stuff....In fact the tanks should be able to fit on top of the rear support bridge assemblies I finished up this fall......Plenty of room in there....

The pictures are the actual steering control console

The blue area is where the ignition switch goes.....I wanted a standard switch....easy to get at and did not need the complex lock assembly buried down in the column...
Since acquiring the S 10 Blazer I saved the original tilt column from it and will swap it into the front cab in place of what I had built....The original column in the front cab had been mangled badly.... Was junk..

All the factory multi function switches in the column from the Blazer were pristine....Just anchor the column steering shaft solid and mount the air control assembly where the wheel fastened on

The black "Nerf pad" allows the operators hands to rest on it and then activate the steering with comfort....Simple pull the lever to the pad.....65 psi....Full steering pressure

Gauge panel can been seen in enough detail to be acceptable.....Heater controls to the right and head lights to the left...
All signal and wiper functions remain as per Ma General.....NOOO the cruise control is not gonna be used...More gauges to handle the air system will end up in an A PILLAR pod.....

 

[Snowy Rivers]

I got a call from the machine shop a bit ago...

The Vortec heads for the 406 engine are done.....
Since they were in the shop I had him magnaflux them just to be sure they were sound,

Heads are perfect....No cracks and they are flat too......Did not need to surface them....

He drilled them for the steam holes and the RH head to work with the old style coolant bypass like the gen 1 engines.

So we can use the water pump off the 1990 Serp drive on the 400 block and everything will be sweet....

He checked the spring retainer to seal clearance with the cam I am going to use (Comp X3 268H )

All good....did not need to cut the guides down....enough clearance already.....

Total package with a set of head gaskets...$470.....
Not a bad deal at all......

Considering that I sold the short block and left overs of the L31 engine and got back all my original $150 plus some....The $470 for a set of fresh Vortec 062 heads is a steal...

Gaining on the engine build.....Getting excited a bit.....

 

[Snowy Rivers]

TYPO ALERT CAM IS AM XE268H

 

[western auto]

TYPO ALERT CAM IS AM XE268H

extreme energy , same cam i just built a 460 with was very happy with that on a chevy build i did for a dirt track car i used to have, tons of torque, snappy throttle , i could just flat foot the throttle out of a turn and hold it down, was faster than 8k race engines i competed with and you couldnt blow it up/ was running stock 86 vette bottom w 100k miles/ angle milled double humps and that cam w a 500 2bbl .......loved it

 

[Snowy Rivers]

In a stock 400 SBC We will not be grabbing the big RPM....
4000/4500 should be about it as far as revs go.....
The big inch mouse motor will provide good torque though.

 

[Snowy Rivers]

Now that the heads are done the time has come to think long and hard about the intake manifold and the carburetor...

The Vortec heads require a special intake manifold that has only 8 bolts instead of the usual 12 bolts found on a small block Chevy.
Several aluminum units are readily available for carburetor applications....So this is a non issue.

The carburetor thing has always been a gray area and I had planned on using a Quadrajet.......
The plan is changing some now.....There are some great "Off road truck" carbs that are designed to operate at fairly radical angles UP/DOWN ..SIDEWAYS and not have issues.

I have had my hands on several of the major players in the carburetor market over the years.....and have always tended to gravitate to the Holley.....
I am looking seriously at the 670 CFM "OFF ROAD TRUCK AVENGER" 4 BARREL with vacuum secondaries and a manual choke......

Manual choke is simple ....pretty much bullet proof (Unless the squirrels eat the cable off)
670cfm is plenty given the RPM range the engine will see.......

Basic connections for the throttle cable......
No worries on tranny connections....THE TH350 does not use a throttle pressure cable....Only a kick down cable.

I am setting the tranny up as a "Full manual select shift box"
The kick down will be eliminated.......

The manual choke requires only a cable......No electric connections or choke stoves and such.....

The Holley carbs can and will ice up in cold damp weather....but the planned hot air box to feed the air cleaner.

The Vortec heads do not use an exhaust crossover at all....So heat for the carb has to be directed from an external source.....
The aluminum intake manifolds conduct heat readily and will get warmed up fairly quick from coolant flow and oil splash on the valley side.

NOT USING AN AIR GAP TYPE...


I had purchased a Q jet back in the early stages of the build....but am really having second thoughts....

I have looked at just about all the options.....From a stand alone setup to run a stock fuel injection to Holley fuel injections to the various carburetors......


SIMPLE...NO MAGIC BOXES ON THIS RODEO just feels good.......

 

[m1west]

you will have more problems with vapor lock than iceing. Better have a good cooling system also

 

[Snowy Rivers]

Electric fuel booster pumps should handle any issues

 

[Snowy Rivers]

Actually...of all the rigs I have owned ...the only unit that ever had a vapor lock problem was a 32 foot gas powered motor home with a Chevy 454 in it....Real hot weather (90's) and hard pulls and then shut it off.....Then it would have issues...Added a booster pump at the tank....No more problem.

The cat will have the fuel tanks above the fuel pump inlet and the lines will be out in the open just under the top rail of the 2100 tub.

Considering the fact that this thing will likely not see much HOT weather running.....it should be fine.......

I had planned on a pass through booster pump JUST IN CASE OF running a tank dry before switching to the other one.....

 

[m1west]

Actually...of all the rigs I have owned ...the only unit that ever had a vapor lock problem was a 32 foot gas powered motor home with a Chevy 454 in it....Real hot weather (90's) and hard pulls and then shut it off.....Then it would have issues...Added a booster pump at the tank....No more problem.

The cat will have the fuel tanks above the fuel pump inlet and the lines will be out in the open just under the top rail of the 2100 tub.

Considering the fact that this thing will likely not see much HOT weather running.....it should be fine.......

I had planned on a pass through booster pump JUST IN CASE OF running a tank dry before switching to the other one.....

Did all the above with the Thiokol, even built a heat shield around the carburetor and a wood spacer under the carb, still did it. Gets extremely hot under hood going slow burning lots of rpm. Todays gas sucks especially winter gas. Basically boils at room temperature. Lots of guys have went with the EFI swap for that reason. Im about to do the same with my Dodge truck. I like simple but I'm tired of it.

 

[Snowy Rivers]

That is an interesting happening.....

My 2100 with the S10 body will have a huge amount of room under the hood area.....
The original S10 grille will let a lot of free air in and around the engine...
You had a smaller Thiokol ?????
The engine is in a tight enclosure .....This can sure change things a bunch.......

We will have to see how it all shakes out......

 

[Snowy Rivers]

After we discussed this issue I remembered a little ditty that came out years ago......I saw this when I worked at a MOPAR shop in the 70's and saw it used later in rigs when the return line systems came into use...
A 3 port fuel filter.....
INLET ---> and two outlets ...The standard outlet to the carb plus a much smaller outlet with a small orifice in it that returned fuel to the tank.....

A constant small flow of fuel bleeding through and returning to the tank stopped the dreaded fuel boiling in the lines.....

I did some further research on the issue........

The advent of the "in tank" fuel pump being a pusher rather than a suction type pump fixed the problem ....And along with a constant bleed return system fixed the mess.

I may scrap the idea of using the engine mounted fuel pump and go to an electric pump......Or may just add an electric as a backup.


With all the old Tucker and other cats out there I would think that the issue of vapor lock would be rampant and if so we would hear about it in the forum ?????
Maybe others will chime in with info on this subject

 

[m1west]

After we discussed this issue I remembered a little ditty that came out years ago......I saw this when I worked at a MOPAR shop in the 70's and saw it used later in rigs when the return line systems came into use...
A 3 port fuel filter.....
INLET ---> and two outlets ...The standard outlet to the carb plus a much smaller outlet with a small orifice in it that returned fuel to the tank.....

A constant small flow of fuel bleeding through and returning to the tank stopped the dreaded fuel boiling in the lines.....

I did some further research on the issue........

The advent of the "in tank" fuel pump being a pusher rather than a suction type pump fixed the problem ....And along with a constant bleed return system fixed the mess.

I may scrap the idea of using the engine mounted fuel pump and go to an electric pump......Or may just add an electric as a backup.


With all the old Tucker and other cats out there I would think that the issue of vapor lock would be rampant and if so we would hear about it in the forum ?????
Maybe others will chime in with info on this subject

Thats why a lot of them went to the EFI conversion. Better starts, no vaporloc and no elevation richness. I think you have to have greater than 15 psi with the new gas to keep vapor loc away. The return line and electric pump pusher are workarounds but how do you keep the fuel from boiling in the bowl of the carb. I used a wood spacer and it still did it. I carried a bucket of snow in the cab to slap on the carb to keep it running at times. They get a lot hotter than you imagine. Back in the day it wasn't an issue because of the gas. The only sure way around it is EFI or AV gas.

 

[Snowy Rivers]

This is a real game changer for sure......
We are at a great time in the build to deal with this too....

I have not purchased an intake manifold yet and have only gave thought to changing to a different fueling system.

I great time for more research and possibly a CHANGE ORDER.....

 

[m1west]

Look at the Holley sniper EFI thats the one I think I'm going with

 

[Snowy Rivers]

Will do....

 

[Snowy Rivers]

I looked at the Sniper EFI.
Nice looking setup .....

I am still very very nervous about complex electronics on anything heading into the bush....

The controller is all onboard in the throttle body.....

We have discussed the issues of heat and vapor lock...

I have battled the electronics in the GM 6.5 diesel injection system that are under the hood in the heat....

Having a fuel system that is all electronic control and not easily repairable on the trail is a no go for me...

Routing fuel lines and such to keep excess heat away is not a problem.....I am going to go with the off road truck avenger Holley 670 CFM carb
Also install the return line fuel filter to keep fuel moving.......The fuel tanks are outboard of the frame and in the rear wheel house area of the body COLD FUEL

I feel far better with this arrangement.....

In a street rig where you can get help if it breaks....A different story......Call AAA and gitterdone.

Another small change order.....

I had decided to go with the hydraulic flat tappet cam mentioned earlier.....

A buddy built a 350 SBC for his JEEP and used a similar cam.....Cam died after about a week......HELLUVA MESS
Total tear down and its not pretty....

The crap made a real mess ....Not sure exactly what all got ruined.....I will eventually get to see....

I do not know what oil he used.....He has built many engines and should be savvy on cam break in...

Since my project still has time to change stuff (No cam bought yet and the heads are still at the shop)

I do not want to deal with the flat tappet cam issues and today's oils

Going to go with a Hydraulic Roller and be done with it...../Then the oil is a non issue....AS LONG AS IT HAS SOME
This changes does require that we do a little more work to the heads.

The valve guides need to be cut down a bit and different seals used...

Going to go with a Marine cam XM270HR (Comp cams) Will use the link bar roller lifters and a couple other tid bits...

This will pretty much eliminate the cam issue.

The Marine cam is designed with ramps the keep the lift speed slower and far better for long duration high speed running
A snow cat is actually more like a boat as compared to a car/truck.....High engine speed and pulling most of the time.....

This particular cam is rated at 1500 to 5500 RPM
218/224 @ .050 (INT/EXH)
.495/.503 lift (INT/EXH)
112 LSA
This cam has about 49 degrees of overlap.....Not real lumpy.....But will have a nice sound and the power will be right in the sweet spot
The flat tappet cam was a 55 degree overlap.....

The Vortec heads like a split duration cams.....The exhaust needs a bit more duration...

Having been heavy into boats years ago...Sort of a soft spot ya know
I spoke to the shop yesterday.....and we will do the needed mods to the heads and be done with it..

A failed cam is just too damned spendy to redo.....Plus all the work involved....

And so it goes....

 

[m1west]

I looked at the Sniper EFI.
Nice looking setup .....

I am still very very nervous about complex electronics on anything heading into the bush....

The controller is all onboard in the throttle body.....

We have discussed the issues of heat and vapor lock...

I have battled the electronics in the GM 6.5 diesel injection system that are under the hood in the heat....

Having a fuel system that is all electronic control and not easily repairable on the trail is a no go for me...

Routing fuel lines and such to keep excess heat away is not a problem.....I am going to go with the off road truck avenger Holley 670 CFM carb
Also install the return line fuel filter to keep fuel moving.......The fuel tanks are outboard of the frame and in the rear wheel house area of the body COLD FUEL

I feel far better with this arrangement.....

In a street rig where you can get help if it breaks....A different story......Call AAA and gitterdone.

Another small change order.....

I had decided to go with the hydraulic flat tappet cam mentioned earlier.....

A buddy built a 350 SBC for his JEEP and used a similar cam.....Cam died after about a week......HELLUVA MESS
Total tear down and its not pretty....

The crap made a real mess ....Not sure exactly what all got ruined.....I will eventually get to see....

I do not know what oil he used.....He has built many engines and should be savvy on cam break in...

Since my project still has time to change stuff (No cam bought yet and the heads are still at the shop)

I do not want to deal with the flat tappet cam issues and today's oils

Going to go with a Hydraulic Roller and be done with it...../Then the oil is a non issue....AS LONG AS IT HAS SOME
This changes does require that we do a little more work to the heads.

The valve guides need to be cut down a bit and different seals used...

Going to go with a Marine cam XM270HR (Comp cams) Will use the link bar roller lifters and a couple other tid bits...

This will pretty much eliminate the cam issue.

The Marine cam is designed with ramps the keep the lift speed slower and far better for long duration high speed running
A snow cat is actually more like a boat as compared to a car/truck.....High engine speed and pulling most of the time.....

This particular cam is rated at 1500 to 5500 RPM
218/224 @ .050 (INT/EXH)
.495/.503 lift (INT/EXH)
112 LSA
This cam has about 49 degrees of overlap.....Not real lumpy.....But will have a nice sound and the power will be right in the sweet spot
The flat tappet cam was a 55 degree overlap.....

The Vortec heads like a split duration cams.....The exhaust needs a bit more duration...

Having been heavy into boats years ago...Sort of a soft spot ya know
I spoke to the shop yesterday.....and we will do the needed mods to the heads and be done with it..

A failed cam is just too damned spendy to redo.....Plus all the work involved....

And so it goes....

Good move on the cam, but you are over thinking the EFI. Just about everyone on the site has changed over to it, and I don't see problems.Better cold start and drivability instantly with better MPG. Plus the no vapor lock or elevation issue. If you are scared carry a carb and regulator with you. 20 minutes and you are going again.

 

[Snowy Rivers]

I am not "Scared" of the EFI....NOT AT ALL... Great for the highway and fair weather off roading. After having been let down out in the brush in nasty weather with no way to fix a rig.....I hate electronics in mission critical parts.

Example

The Military HMMWV Always had a mechanical injection pump......
The civilian unit with the same 6.5 diesel had the DS4 electronic pump.....Absolute nightmare......When they quit....YOU ARE SCREWED.....

Mileage on this beast is not even a worry.....PACK PLENTY....The engine is going to eat lots of it.

I do not really want to carry parts to fix a breakdown.....Fix the breakdown before it happens....Keep things simple.
WE have an old hay rig here at the ranch that has a 350 Chevy in it....Standard 4 bbl carb......LOOOOOOONG BED .

We run this thing in the fields hauling hay all summer.....Never ever had any issues......
Old long wheelbase 3500 4x4 truck that's had 4 feet put in the frame.....LOOOOOOOOOOONG RIG..

Dual factory fuel tanks with the factory fuel switching.....Absolutely never had any issues.

This rig idles through the fields in granny low while the guys toss hay on.....Then run down the county back roads back to the barn......All hot weather and never any issues.......Always starts up easy and always ready to do it's job.....

Only time it failed to go.....A squirrel had chewed the fuel hose in half where it jumps from the frame to the pump....WE could smell that problem

The tried and true is my choice on this one.....Far cheaper to go with the 670 Holley 4bbl than the EFI as well...

I had one of the real early Analog 2 barrel Holley injection units back some years ago in a 1/2 ton 4x4 shorty that I bought at a garage sale for $25
350 HAD A BIG HOLE in the side...I dropped in a nice 455 OLDS and added the Holley Projection.....
It was fine.....But....I do not like the reliability of the diode boxes when help is far away and possibly not going to get to ya before you freeze.....

I always go back to the HMMWV.....The mechanical injection was as bomb proof as possible....All the magic boxes the military uses to do things ...they used a mechanical device to make sure the boys can get the hell outta Dodge when the SHTF.....
This says a lot

HEAT KILLS ELECTRONICS.......Far more regularly than vapor lock issues...especially in a cold weather rig...

Anyway.......Too many failures with the diode boxes and I am very gun shy......One mouse or Squirrel.....Zoooop..game over....


Anyway....Just my opinion......and a lot of years in the game....

 

[m1west]

Its your project

 

[Snowy Rivers]

That is the truth......
I don't mean to be contrary....or argumentative for the sake of stirring the chit.....But I cut my teeth in the automotive game in the 60's and 70's and watched all the high tech gadgets come into being through the 80's....90's and 2000's

I have seen a lot of failures and just plain "What were they thinking" come and go.

I am real slow to jump on the band wagon....
Some stuff is fine.....But to me it seems that there is an extreme bent today to get a computer attached to everything.....

I have an uncle who's family run a couple big farms/ranches ...These guys have a buttload of huge equipment they use to handle the cultivation duties.....

In point they recently purchased a big articulated Tri track tractor to handle some of their large tracts of ground..

I don't know what it cost.....Likely in the Half mil arena......This beast is a rolling computer that goes out and plows the dirt....Amongst other things.

They had only had it a few weeks and one morning WAAAAAAAAAAAAAAAAAAAY out in the field it suddenly refused to move past a crawl.....

The service light came on and all work stopped..

Took the dealer tech boys several days with their laptops hooked up to it to find out that they still did not know what was wrong...

Enter the factory tech boys made no better progress....

They finally had to limp the monster back to an access road and get it on a low boy and haul it to the shop.

Another week or so went by with lots of head scratching and still no answers......
Finally one of the local dealer techs spotted a mouse turd in the main control panel .....

Little beastie had gnawed a small wire and damaged the shielded cover on it.....(All CANBUS CONTROL)
Stinking mouse brought the big beast to it's knees.........

The high tech is just too vulnerable in many cases.......This instance cost the farm a lot of lost production.

There was not any danger to life and limb but one helluva lot of inconvenience.......

Out in the cold and wilds a failure could easily result in serious threat to people...

The big commercial groomers are all set up with canbus computer controls and such......But usually the operation has several machines and if one breaks down they send help to either fix it or drag it in......The operator and or passengers are simply inconvenienced and probably not in much danger....

A private cat is a different story.....

Why build a rig that is complex and not easily diagnosed and repaired on the trail.......

OLD SCHOOL worked really well....Yeah...some of the new stuff is waaaaaay cool, WHEN ITS WORKING...

But when it quits.....life sucks...BAD......

Yes...it is my project, and I am trying hard to avoid building in a bunch of issues that can be avoided,,,,,,,

The cost of the computer EFI is not exactly cheap......And it has that one built in issue that worries me.....Micro Electronics

A simple Carburetor is about as bomb proof as it gets.....


I'm gonna error on the side of simple......

IIRC an old GM engineer once said "Parts left out never fail"

 

[m1west]

Tuned up my Dodge truck yesterday. New wires, plugs ,rotor. Still ran like crap down low. Ditched the timing light and advanced the timing by ear. It came alive and actually runs good now, no popping, hesitation or lazy. The balancer is new but something must be wrong on the timing marks. When I put the motor in it was set with the advance plugged at 14 degrees BTDC and should have given me 34 degrees all in, obviously not true. I think will leave it on for now. The only other issue will be when I drive it up to the mountain. We will see.