Moparts

6cyl to 8cyl

Posted By: mopar360

6cyl to 8cyl - 12/02/09 01:28 AM

As some of you know i am a young kid looking for his first car (a mopar of course). I was wondering, if i bought a car with a 6cyl motor what would it take to be able to drop a 8cyl motor, 350-440?
Thanks
Ethan
Posted By: scratchnfotraction

Re: 6cyl to 8cyl - 12/02/09 01:40 AM

couple ways to do it from /6 to v-8

change the K-frame out to a v-8 one

use the conversion mounts

and if its old enuff /6 you can use a truck engine mount on the pass side and a stock v-8 bracket on the driver side when swaping from /6 to sb using the square bisket rubber mounts
(old hot rod trick)

a 350 is gonna need a torch and welder as it would be a chebby engine

a 383 would be the same set up as a 440 though,k-frame or conversion mounts

the tranny will bolt up in the stock location and use the tranny mount for that yr and style xmember

if going BB in an A-body the exhast is the biggest problem

and a 383 B engine is a little better fit as the 440 is wider at the valve coves and mucho tight on clearance

good luck
Posted By: dave571

Re: 6cyl to 8cyl - 12/02/09 01:47 AM

He could have meant the 350 B motor.
Posted By: scratchnfotraction

Re: 6cyl to 8cyl - 12/02/09 01:54 AM

yea,I forget that one,my bad

sorta like a chebby guy and his 383

it would be the same as any Bb engine swap

Posted By: mopar360

Re: 6cyl to 8cyl - 12/02/09 02:15 AM

Quote:



and if its old enuff /6 you can use a truck engine mount on the pass side




why can you only use it on the pass side? or can you use it on the driver as well
Posted By: Anonymous

Re: 6cyl to 8cyl - 12/02/09 02:46 AM

You'd be time and monies ahead to get a v-8 car in the first place. That way you don't have to piece together things like a K-frame, motor mounts, wiring etc.

The v-8 cars usually have slighty thicker torsion bars, more leaves in the leaf springs, bigger brakes (often disc in the front) too.

Trust me, I took a /6 3 on the tree car and made it into a 440 BB with 727 auto!
Posted By: scratchnfotraction

Re: 6cyl to 8cyl - 12/02/09 12:56 PM

you only use the one truck bracket cause of the spacing on the k-frame and its not in the same spot as a v-8

the driver side would be the bracket they used on a v-8 k-frame before the spool types

it will use the same rubber bisket mount as the truck and early v-8s

driver side is close to block and pass side is got a good size gap the truck mount takes up the space

bolts right in

wont work if its a spool type /6 though

Posted By: Mr.Yuck

Re: 6cyl to 8cyl - 12/02/09 01:24 PM

like mentioned, a 318 Valiant would be the way to go. They aren't half as ugly as 73-75 darts amd the can be had cheap. You could do simple things as you get the cash and drive it. Headers, intake carb, cam... You'd be suprised how much you can pick up with little upgrades.
Posted By: Reggie

Re: 6cyl to 8cyl - 12/02/09 03:43 PM

Quote:

you only use the one truck bracket cause of the spacing on the k-frame and its not in the same spot as a v-8

the driver side would be the bracket they used on a v-8 k-frame before the spool types

it will use the same rubber bisket mount as the truck and early v-8s

driver side is close to block and pass side is got a good size gap the truck mount takes up the space

bolts right in

wont work if its a spool type /6 though





What scratchn said. On trucks and vans, the bean counters figured out how to use the same frame for /6s and V8s. The frame was set up for /6s on the passenger side and they used a conversion type mount for V8s. Attached is a pic posted by a member here showing a V8 truck mount adapted to a /6 car.

Attached picture 5641026-Van_truck_V8_Mount_Slant_6K_Frame.JPG
Posted By: sharpie

Re: 6cyl to 8cyl - 12/02/09 05:15 PM

I went from 6cyl to 8cyl no prob





Posted By: rogue_leader007

Re: 6cyl to 8cyl - 12/02/09 10:14 PM

If going from a /6 to a v8, wheather it be small or big block, you'll also have to upgrade torsion bars, stronger suspension, and larger breaks. A slant was backed up by a slant only 904, so that'd have to go as well, not to mention the 7 1/4 diff.

From one young gun to another, save yourself the headache and find a factory v8 car. (unless, like me, you live in fricken ocean of slant 6 cars) *wonder's why people in NE GA only bought the leaning tower of power back in the day*
Posted By: DusterKrazy

Re: 6cyl to 8cyl - 12/02/09 10:20 PM

So..a passenger side motor mount from a truck and a stock v8 motor mount on the drivers side will work?

Not to hi-jack but what about going from a small block to big block using an original v8 k-frame?
Posted By: mopar360

Re: 6cyl to 8cyl - 12/02/09 10:24 PM

Quote:


Not to hi-jack but what about going from a small block to big block using an original v8 k-frame?


yea i was just going to ask about doing that!
Posted By: DusterKrazy

Re: 6cyl to 8cyl - 12/02/09 10:26 PM

Quote:

If going from a /6 to a v8, wheather it be small or big block, you'll also have to upgrade torsion bars, stronger suspension, and larger breaks. A slant was backed up by a slant only 904, so that'd have to go as well, not to mention the 7 1/4 diff.

From one young gun to another, save yourself the headache and find a factory v8 car. (unless, like me, you live in fricken ocean of slant 6 cars) *wonder's why people in NE GA only bought the leaning tower of power back in the day*



I agree on this. But I will say that the torsion bars dont HAVE to be upgraded unless you just want to. Yes larger t-bars will make it handle better, however lots of drag racers use the /6 t-bars for quicker weight transfer. Do yourself a favor and spend the $$ on some GOOD brakes.
Posted By: scratchnfotraction

Re: 6cyl to 8cyl - 12/03/09 12:30 AM

what DusterKrazy said

I ran the 68 dart with /6 t -bars with a SB got good lift and traction

got to watch decel though,it falls just as fast and faster if on the binders

x2 if its a BB

just another old hot rod trick

they made a /6 heay duty 727 tranz also,cop cars,taxis... ect.

the spider gears are a weak link for the 7 1/4 also..they did have a sg unit for them that tuffed them up some as well,but no match for a 440

most 7 1/4 I blew out ( in my neck of the woods) was from the one wheel peel for 2 blocks at a time

the spiders would seize up on the cross pin and start suregripping till it broke a couple passes later

yes,thats a perfect pic of the pass side with truck mount...need a shot of the other side too...thats been a while back for that pic

I will make sure to hit the save button..thanks for reposting it

Posted By: scratchnfotraction

Re: 6cyl to 8cyl - 12/03/09 12:46 AM

trucks didnt come with spool mounts,IIRC so thats out for a sb and spool type mounts,gotta chop the /6 spool mount and reweld it in the spool type k-frame for sb v-8

IIRC,you need to cut the pass side and maybe the drive side mount off the k-frame and move it around some for a BB on the bisket type k-frame,may have to add a notch to it also some where on the drive side

other mods would be welding it all up on stock welds and adding a skid plate and reinforcements to it while your modding it for mounts,

myself,I would just use the conversion mounts or bolt up a BB k-frame

Posted By: dave571

Re: 6cyl to 8cyl - 12/03/09 02:02 AM

Quote:

... I will say that the torsion bars dont HAVE to be upgraded unless you just want to. Yes larger t-bars will make it handle better, however lots of drag racers use the /6 t-bars for quicker weight transfer. .....



Absolutely true.

Generally, slant 6 bars are considered the smallest you can run on the street (actual drag race bars are even smaller)

BUT I will add, If talking A body, depending on the year of A body we are talking about here, they may be the same bar anyway. Later A's(ie 73 76) used the same T bar whether they were slants or v8's. Same brakes too, as long as they were 4.5" bolt pattern cars.
Posted By: sreinheimer

Re: 6cyl to 8cyl - 12/03/09 02:25 AM

I put a 318 into my 67 /6 dart a couple years ago and if you can find a v8 car go for it. It will be cheaper than converting to a v8. All the little things add up. I still had the 7 1/4 diff and surprisingly held up and i ran /6 T-bars and 9 inch manual drums all around. I would not suggest keeping those brakes as it can get very hairy at times.
Posted By: hemi-itis

Re: 6cyl to 8cyl - 12/03/09 02:29 AM

I would go with a motor plate,leaves lotsa room for headers.I have 6 cyl t/bars in my junk.With the spool it don't like to turn anyway.
Posted By: rogue_leader007

Re: 6cyl to 8cyl - 12/03/09 10:21 PM

Then again, you could always go with the "dare to be different" route that my buddy did with his 64 dart, and see what kind of power you can get out of the ole leaning tower of power. Clifford offers 4bbl intakes and a header for the slant.
A couple of years ago, I saw a slant on ebay that was bored and stroked to 340ci.

But still, you just can't beat that V8 sound and torque......

So, a truck mount on the passenger side, and a normal mount on the driver's? That combo work with /6 to 360 swap as well? Save me some headaches with my 70 dart if it works.
Posted By: DaytonaTurbo

Re: 6cyl to 8cyl - 12/03/09 11:09 PM

Depends on the type of car.

Like said conversion motor mounts and new engine/transmission at the minimum. Shorter driveshaft if you're going to a 727 transmission. I ran a slant 6 rad behind a 440 for a while, lasted until the rad rotted out completely. A slant 6 is no lightweight motor so stock brakes and torsion bars will do fine. Brakes may be so-so depending on the car. If you're starting out with a slant 6 car with manual drum brakes all around, then it might be a bit sketchy. But anything with power brakes or discs will do fine IMO.

Remember you'll also likely do a new exhaust system at this time.

It's not a hard swap, just if you're young, you may not have access to the necessary tools like an engine crane. I would drive the slant and build your v8/trans on the side and swap them out when you're ready, in terms of money, skill level and tools.

That will get you running. Shortly thereafter you'll likely need to upgrade to a stronger rear diff.
Posted By: scratchnfotraction

Re: 6cyl to 8cyl - 11/15/11 03:51 PM

for vdriver

maybe help

IIRC sharpie used the conversion mounts

look like the same set up just after market looking at the pass side mount in his pic

wow 09'
Posted By: Rug_Trucker

Re: 6cyl to 8cyl - 11/15/11 04:14 PM

If you decide to keep the /6?

www.slantsix.org
Posted By: zrxkawboy

Re: 6cyl to 8cyl - 11/15/11 11:53 PM

As others have mentioned, it depends on the body style. For example, Schumacher does not make conversion mounts for my 67 Belvedere, so I have to change the k-member.
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