I have an 85 D100 with a /6 1barrel. The truck is nicknamed "The Gutless Wonder" because it won't get out of it's own way. There is no power at all. You basically have to keep it floored to try to run 70mph interstate speed. So I am looking to upgrade a little in the power department. Now I'm not looking to make a hot rod just some reasonable, usable power. I am giving some thought to tring to go to a 2 barrel setup rather than the 1 barrel it came with. My question is, Is it worth the effort or should I just v-8 the truck and forget the old slant six? Will I get a fair amount more power out of the trouble going to two barrel,because of all the linkage change etc... to make it worth it? Anybody did this and have any insite.
Thanks

I would definetly put a v-8 in it. Just putting a 318 will wake it up. 318's are cheap and lots of people give those away. Also, you can go one step further and do a nice 360 for it. Either a 318 or 360 you'll enjoy driving the truck that much more.

Then it's either worn out, or something is wrong with it. It could be nothing more than worn out plugs, wires, have retarded timing, need a carb rebuild, etc. Do you maintain it, change the oil, or has it been run into the ground? Does it have a huge exhaust leak? Does it miss? You should barely be off idle to cruise at 70, even in a slant six.

Sure, you can put another motor in, but it would be a lot easier and cheaper to fix up what you got if it just needs some attention.

Slant sixes are gutless, mine won't pull a loaded 24' enclosed car trailer.

It will pull a 4000lb plus '67 Hemi Charger on a 2000lb trailer and it's pulled a 5500lb John Deere tractor on the same trailer before.



Then again, I did upgrade to a 2bbl Super Six BBD so I cheated.
It gets 20mpg hwy @65mph where my old 318 would only do 17mpg.
If your going to V8 it, why not go 440? Compared to a big block, small blocks are gutless! Remember, everything is relative.

i had a /6 in a A-100 van had no prob. cruisin 80 mph.

What Vincent said I'd at least diagnose it & see if it's just worn out or if it has an easily fixable problem. You have other V8 trucks in your sig so you know what's involved in swapping and the power increase you'll have when you're done. Myself if I had several trucks I wouldn't mind keeping one with a /6 but I would want the eng to be in pretty good shape

If you wanna go with the normal wave of people but the Sixes are better on fuel if you get it just right. 1bbl IS a gutless wonder...my 70 Dart had a 225 1bbl. I swapped out to a 2bbl Cast Iron intake and put a 2bbl 500cfm...ran better...not great. I swapped out the cast iron and found a 4bbl Offy Aluminum and ran a 4bbl 390cfm. Ran better and was content...Then I swapped out the atrocious exhaust manifold. Put in the 6-to-1 MP header...Ran better...not great...the #4 pipe had to be crushed to fit the steering pump. Eventually switched out to the Clifford Tri-Y Dual headers. Breathed ALOT better. Sent out a spare cylinder head and had it rebuilt. 5 angle valve job, new large valves (1.61/1.34 IIRC), mild Porting...I wanted to put 5/16" vave stems from a Ford but the guy said it was wasted money. Bolted it on....difference was night and day. Had to get rid of the 390cfm Holley....tossed it and went with a 500cfm Edelbrock.....I broke the rear end. 3 of the 4 spyder gears went bye bye. Don't underestimate the power of a slant. I was taking out small blocks with mine and I was the only muscle car on the road in my area during the gas crunch of 2002/2003. Went back and forth from LA to Vegas on numerous occasions.

If you are worried about the linkage, switch to a Lokar for the kickdown or go one and done with a Bouchillion Kit that you can use from a Slant to an RB and set that throttle/kickdown any way you see fit.

While you are up to changing things (If you keep the Slant) put in a remote oil filter. I hated bathing my suspension in oil at every oil change

More pics on the link in my signature but..

That's an awesome setup. I had a Clifford 4 bbl intake on my /6. We fabbed our own carb adapter out of a phenolic blank, and turned it 90 degrees so the primaries were parallel and closest to the driver's fender. I specifically wanted to do this for improved distribution and drivability. Finally, we used chrome drain pipe inserted into the primary holes of the adapter, down into the plenum (not quite to the bottom), and cut them on an angle so as to make the center cylinders' pull from the carb a little bit longer, like the outer cylinders.

It worked great. Carb was from a 273. It was all experimental. A little too much CFM, but it was fine if you waited until about ~3000 to open it wide. We eventually put a (noisy) 3.55 suregrip in it (up from 2.94 w/ wide ratio 904), that made it real fun.

Like you, I started with the super six 2 barrel setup from the pick-yer-part. With an open element air cleaner, it was fun, but the extra 10 or 15 hp wasn't enough.

It was still slow.. but it was ridiculously fun to drive.

The kickdown linkage I kept stock, believe it or not. I had this interesting setup where I had a stock location mount for the kickdown rod up by the carb, and I used a spare throttle cable to translate the motion from the 90 degree rotation back to where it would normally be. It made the pedal a bit hard to push (lol,) but it worked.

I had digital pictures of this. Probably sounds like I'm full of crap.. it was on my college server and I never re-saved them again before they killed my account after grad. oh well. i still have all the parts..

I ran a slanty for years in my '68. It ran very well for a slant, but it would only pull down 16 to 18 mpg on the highway at 75mph and 13 to 14mpg around town.

I had a two bbl, slightly ported head with oversized valves, an RV grind cam, bumped-up compression and Dutra Duals. In fact, the motor was done by Doug Dutra.

Like I say, it ran great, but I always wanted more. I ended up pulling it to put in a 2001 360 Magnum with fuel injection and some other mods. I expect to get way more power and equivelant or better mileage when my foot is out of it.

Dutra duals! I also have a set of those, never put on yet. Those are rare, not many have them.

This thread is making my head spin a little. I have an aluminum 225 in my garage, packed away. I was going to put it into the car with the 4 bbl I was just referring to (an 81 police dippy) but life got in the way.

I like your fuel line treatment

FYI, Doug is still selling Dutra Duals.

OP-as said before, make sure the motor is in proper tune and good condition before you give up.

I have an intake and kickdown if you decide to go with a 2bbl

Thanks for all the replies so far. As far as the condition of the engine, truck now has 92,000 on it. Engine is very quite and use no oil to speak of. No engine miss at all. Plugs and wires have been changed at some point and time but not recent. Oil is changed at 3000 miles by me can't really speak for previous owner. Carb is junk though. Cranks right up cold but once it gets warm you have to crank for a little while and floor the fuel pedal to get it to start. When the truck is warm and say you stop somewhere get out and then come back a few minutes later there is a strong smell of fuel. So I am sure the carb needs work and that's where my delima lies. Do I spend the money to fix the 1 barrel because the 2 barrel wouldn't be that much of an improvment or just say forget it all and spend the money on small blocking the truck. I like what pyper70 did there will have to do a little parts researching on that to see whats available. Thanks again

Just to add more "fuel" to this fire...
I know this is ancient history at this point, but I ran my Demon 225 in Stock NHRA at Englishtown. Took out quite a few small blocks ('74-'82). The national record was 15.2 @ 83 mph at the time. I got it down to 16.92 @ 82 mph and still street driven. Specs' (to my recollection): +30, stock spec/blueprint cam, aluminum 1 bbl intake, hooker headers, 904 manual shift, stock stall converter, 4.10 7.25 rear.
Car weighed in about 3300# wet & loaded. Consistantly in the points for 6 years.
Obviously, if I had a converter, blueprinted the head it would have been faster.. I did play with dual Holley 1 bbls and it felt faster, but I ouldn't prove it. the slantys can be real torquey for sure. This is interesting, cuz I was just reading an article in Mopar Action about /6 vs small blocks. Bottom line, 318's and 360's are cheap and plentiful and cubic inches trump uber alles...I did love my 225, just the lure of a 340 won out .....

FWIW, I was re-curving my slanty's distributor. You know, welding up the advance slots and then filing them back with a small chain saw file that fit just right. It took about 6 tries to find where the motor liked it best.

In my case, one of the greatest low rpm & midrange driveability improvements I made was to recurve the distributor. Mine ended up liking to be set at 25 initial with 32-34 total total. The started never kicked back, it never gas knocked and it really transformed how the car ran off idle and into the midrange. The top end never changed, which is to be expected, as the total timing remained the same.

I also routed the vacuum advance to manifold vacuum. which brings the timing up into the mid 40's at idle and cruise etc. Of course it immediately drops back toward 32 when the throttle is opened.

This was really a game changing adjustment for my motor. It pissed off a lot of close minded, know-it-all guys who have never tried it, but swore it would never work over on the slant 6 forum.

Give it a try, you can always file the slots longer and run less initial if you find it doesn't work for your ride.

At the time of all my modifications...I had 4 383s in the garage...two 440s....and I went out purposely and bought a 340 to make a 340 Swinger clone. The Slant prevailed because it was the underdog. I sold the 383s...both 440s went into both Chargers and the 340 was sold for quite the return on investment. I had all the parts there....and still didn't follow through...Now even Slant parts are scarce and slowly rising in price.

If you start wanting crazy parts for the Slant look up Cox Bros out of Ohio...I remember buying bearings, timing sets, rocker arms etc..not cheap...but they were made in the USA

Either just V8 it and don't flush money down the toilet on the slant or simply find a good 1bbl carb to put on it and live with it. I would be searching for a 92-95 dodge 2wd truck or ram van with the 5.2 or 5.9 magnum. 2wd 5.2's are not that hard to find. Drop the motor and trans into your truck. You will get double the power with same or better mpg with the 5.2 and the overdrive transmission. I say 92-95 because those are the easiest years to retrofit into your ride. 96+ the transmission and computer changed making the swap much more difficult.

Friend's /6 '67 Barracuda ran 20 in the quarter. Put a 2bbl and header on and ran 18sec in the quarter, but his gas mileage dropped from somewhere in the 20s, to 14mpg. Went 360, gas mileage stayed the same, but now in the 14s. Then went 440, and same mileage, in the 14s still, but a lot faster MPH. He couldn't hook, but a lot more fun to drive. These were all with bone stock, worn out motors, except for the /6 header.