Slant six or v8 swap for use in a truck

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lud

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I have no idea if this is the right place to post this thread, but I have a beautiful 225 slant six I prettied up from a 63 Plymouth Belvedere shoved into my 1982 dodge d150. The engine only has around 80k miles on it, I got rid of the one barrel (holley model 1920) in exchange for a 2 barrel (carter Hightop bbd) which required changing the intake and exaust manifold. Easier said than done. But it's done did. There was this floppy thingy inside of the exaust manifold but it's not there anymore. Prolly some EGR save the planet stuff idk. This alone on top of a brand new clutch really increased the power. Like alot alot. I increased the tires from a p195 to a p235 so it needs geared from the 3.23 it's at. To a 3.55 or 3.73 maybe even a 4.11 ... sounds expensive. I can cruise and get up to speed pretty good, even with a quad in the back of the truck. Or about half a cord of wood. I dragged a camper out of the hole it sunk into from sitting aswell. I love the gas mileage that come with the engine and gear ratios involved. The question or rather discussion I want to have is whether or not it's worth going to a v8... the slant will never sound or perform like a v8 would, and the slant refuses to spin the tires and once your up to speed it has no power, it has a stick shift yet I can’t drop the clutch and let her eat... I got a cool truck that looks quick, sounds mean but ain't. It's got balls in 1st and second gear.. is it a gear problem, do I have to mill the head, mess with the spark make it happeners. Transmission? Cam it? 4 barrel? Bigger 2 barrel? Or would it just be cheaper and better to get a junk 318 that turns over and completely rebuild it. I should mention this trucks my daily. (Threw in a picture of the truck when I got it cuz im proud of it) I don't have any newer pictures with the 2 barrel on it , aswell as I was not able to upload any good pictures because this website doesn't allow for pictures of such quality. Be mindful of budget. Like let's say you only had $100 a week to spare on this. Any input is welcome

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if it's your daily, don't mess with it.

but let's play devil's advocate here a moment. going to V8 will require a whole host of accoutrements for the extra two cylinders. for starters, you'll need a V8 bell housing and all the peripheral bits- Z-bar, fork, possibly a different flywheel & clutch. you'll need to add and modify your exhaust. motor mounts. a bit of wiring. sorting out of the radiator inlet/outlet in relation to the corresponding bits on the block.

and that's all just to get it in there.

the rear end? i dunno, i'd probably try and find one at a 'yard and just stab it in. though if it's anything different that what's en there, expect to pay to have the driveshaft shortened and other faffing about: e-brake cables, brake line adapter fittings/lines, possibly u-bolts and shock plates. or you could see about locating some gears, maybe used and swap those in, and if you're not setting them up yourself that means pulling the rearend out and taking it to somebody to pay them to do it.

my guess is that you'd probably spend about 2K swapping over-- not including the cost of the motor.
 
I have 2 Dodge 2wheel drive trucks. A 88 D-150 with a 360 4V 727 trans, and a 64 D-100 with a 225 slant 2V and A833OD trans. I don't remember the rear ratio of the 88, but the 84 has a 3.91 SG 8 3/4. Both trucks have AC, PS, PB, cruise control.
The 88 will out pull the 84 and has more power/speed at 75 MPH pulling my race car. The 88 truck will get 9.5 mpg normal driving, or 9 mpg towing.
The 84 truck will get 13 mpg towing, never checked the milage not towing. Myself, I would rather have the fuel milage. I don't need the additional power of the 360 engine.
Not positive what I would do if modifying one of those, today. I might consider building a 318 engine for economy, and using a A500 or A518 lockup trans.
Another thing to consider, is adding a turbo to the slant and limiting boost to around 5-7 lbs.
 
Appreciate all the input, a turbo would be pretty cool not going to lie, and I honestly don't have the money to do a swap. Unless I find an old dodge with everything in it and tweak the engine abit...
 
You have the 2 BBL I would deck the block/mill the head to get in the low 9's compression, oversized valves, camshaft to go with that 2 BBL/valves and I think the 225 would surprise you and still get good mileage.
 
lud said:
Appreciate all the input, a turbo would be pretty cool not going to lie, and I honestly don't have the money to do a swap. Unless I find an old dodge with everything in it and tweak the engine abit. Wouldn't mind building the slant up. Save and cash, order the gaskets and finding a place to mill the head. Oversized valves? How do I go about acquiring these? Like what am I looking for. And as far as a cam goes, what cam would you guys recommend?
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You can get the valves at Hughes if you want, Slant 6 (170-225 c.i. 1960-1987). My machine shop buddy got the valves/seats/springs from his sources and measurements. I would recommend Oregon cams 1206 or 819 for torque/towing. The valves help at higher RPM where the stock head starts to wheeze out, over 3500-4000 RPM.
 
Jim Kueneman said:
You can get the valves at Hughes if you want, Slant 6 (170-225 c.i. 1960-1987). My machine shop buddy got the valves/seats/springs from his sources and measurements. I would recommend Oregon cams 1206 or 819 for torque/towing. The valves help at higher RPM where the stock head starts to wheeze out, over 3500-4000 RPM.
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How much would you say the cam will run me up? Comp cams seem budget friendly. Really appreciate the info, thank you
 
Also is your distributor fully functional? Mechanical advance working, vacuum advance working? Using this

How to limit mechanical advance in a mopar distributor, tuning for street, strip or all out racing, cure that rich stinky idle, win races

but with the springs

Mopar Distributor Mechanical Advance Timing Limiter w/spring kit 610877674114 | eBay

I use the lightest springs to get more advance faster. Set the plate to the "10" position. With it set at "10" with an initial advance of about 18 degrees it will give you about 30 degrees with the mechanical full in (if you have a timing light that has a timing adjustment then I would set the full in at high RPM to 30 degrees and let initial be whatever it ends up. While there make sure the vacuum advance is working (plug it into a vacuum port and make sure the timing moves). Again with a fancier timing light it is nice to measure the amount of advance you get with the vacuum canister unplugged and then plugged into full manifold vacuum to make sure it is working. It should give you 18-24 degrees'ish.

This can make a big difference in how much power the 225 has at cruising speeds.
 
Jim Kueneman said:
Also is your distributor fully functional? Mechanical advance working, vacuum advance working? Using this

How to limit mechanical advance in a mopar distributor, tuning for street, strip or all out racing, cure that rich stinky idle, win races

but with the springs

Mopar Distributor Mechanical Advance Timing Limiter w/spring kit 610877674114 | eBay

I use the lightest springs to get more advance faster. Set the plate to the "10" position. With it set at "10" with an initial advance of about 18 degrees it will give you about 30 degrees with the mechanical full in (if you have a timing light that has a timing adjustment then I would set the full in at high RPM to 30 degrees and let initial be whatever it ends up. While there make sure the vacuum advance is working (plug it into a vacuum port and make sure the timing moves). Again with a fancier timing light it is nice to measure the amount of advance you get with the vacuum canister unplugged and then plugged into full manifold vacuum to make sure it is working. It should give you 18-24 degrees'ish.

This can make a big difference in how much power the 225 has at cruising speeds.
Click to expand...
Really appreciate this, to be completely honest that stuff probably hasn't been touched since 1963
 
I'm biased towards the slant 6, so keep that in mind with my answer.

You've already admitted in your own words the slant 6 does everything you want to do with your truck now. You simply would like maybe a little more leverage (gear).

You said "the slant will never sound or perform like a V8" and that's true. It's also true a V8 will never sound or perform like a slant. The 225 has a mechanical advantage over any factory Chrysler V8 in its 4.125" stroke. That's maximum torque just cracked off idle. Great for a truck. Chrysler knew this and didn't shy away from putting the slant 6 in trucks as big as a Dodge D500 dump truck. They made millions of them. While it's true they never won any races, they did the job and did it well.

The slant 6 is different. When we drive Vixen (my 64 Valiant) to any and I mean any car event, everyone always expects to see a small block and the look on their faces when they see the slant 6 is priceless. She usually gets tons of attention wherever we go. Look around if you go to cruise ins and see how many small blocks there are. It gets boring.

You already admit you know the slant will never be a V8 and you're right. Conversely, the V8 will never be a slant, either. It's a decision you and you alone are going to have to make. Whichever way you go, keep us posted!
 
We have twin trucks. Mine is also an 82 D150, slant and A833OD. You don't mention what trans you have, is it the granny-low 4-speed or the OD 4-speed? If it's the OD, a far cheaper way to go is just change the rear gears. I put 235/70-15 tires on mine, they are 29" tall. I believe my rear gears are either 3.23 or 3.55 (can't remember). I'm going to change them to 3.91. That will be a livable deal around town, but drop the cruising RPM to somewhere around 2200 on the freeway.
 
I love the slant and the uniqueness, it also just makes my truck seem more ratty (which is what I'm going for) I have p235 75 r15 tires on my truck, and a A833OD with a 3.23 rear end. I can't remember what it is, I think a 9 1/4 axle. But the sound of a v8 can't be replaced, the power can't either but how much power do I really need. I've made up my mind I think tho, to keep the slant. It's an amazing engine that's already in it, has low miles, runs amazing and starts evertime. I've been around it in and out. I like the idea to mill the head and change the valves, but first I'm going to mess with the electrical bits and the timing.

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From what I understand, the 63 slant six is different from the rest?

-EDIT- in the pictures I noticed I have to tighten my radiator cap... lmao
 
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That's an 8-1/4 not a 9-1/4 rear.
The only real difference in a 63 engine besides a cast crank vs the original 82 engine's cast crank. The head is slightly different but the important part (combustion chamber design) is largely the same

I just overhauled a 74/6 to put in my 85, is did the oversized valves and shaved the head and block, converted to the 2 bbl, and had oregtcams grind me an 819. I'm not driving it yet, I'm slowly doing bodywork now.
 
volaredon said:
That's an 8-1/4 not a 9-1/4 rear.
The only real difference in a 63 engine besides a cast crank vs the original 82 engine's cast crank. The head is slightly different but the important part (combustion chamber design) is largely the same

I just overhauled a 74/6 to put in my 85, is did the oversized valves and shaved the head and block, converted to the 2 bbl, and had oregtcams grind me an 819. I'm not driving it yet, I'm slowly doing bodywork now.
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Also the crankshaft register is smaller on the earlier engines....although that doesn't affect what he's doing, since he's running a manual transmission.
 
Yup and I hope he's running the 63 flywheel because of that
 
I had a 63 engine once to replace a blown engine in an f body back in late 80s. . I found out the hard way about the early/late torque converter mismatch.
I rebuilt that 63 engine and had to take the crank out of the bad engine (also wasn't the original engine from the car) and have the bad engines crank machined to put in that 63 block to make things work
 
volaredon said:
That's an 8-1/4 not a 9-1/4 rear.
The only real difference in a 63 engine besides a cast crank vs the original 82 engine's cast crank. The head is slightly different but the important part (combustion chamber design) is largely the same

I just overhauled a 74/6 to put in my 85, is did the oversized valves and shaved the head and block, converted to the 2 bbl, and had oregtcams grind me an 819. I'm not driving it yet, I'm slowly doing bodywork now.
Click to expand...
I started to do some body work but since it's started to be my daily driver it's hard to find time to finish...
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lud said:
What would you guys say, is or should be the maximum I should tow/haul?
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An A body on a trailer. It's not necessarily about what it will tow, but what it can STOP with.
 
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