Slant 6 in 37 coupe? Anyone have one?

Hey all

My 37 D5 came with an LT1 and 6 speed trans already installed. Not my choice of power plant but it is what it is.

I just picked up a well running slant 6/904 combo which was plucked from a 67 Coronet for free! (well a bottle of rum actually. Love the barter system) Also got the driveshaft and rear end as well thrown in!

The LTI actually fits pretty well in the coupe, but I wanna prep the slant 6/904 to eventually install it in place of the chev stuff.

This is my first exposure to the slant 6. Will there be any fitment issues that I should be aware of. Haven't really sized the /6 up very well yet, as it is still sitting in the back of my truck while I am working 350 km offshore. JUST picked it up. The front of the car is fairly narrow as you know, but like I said the LT1 fits in there pretty good. I'm wondering if the sheet metal is wide enough to accommodate the "lean" of the /6.

I know that a small block might be more practical, but I'm just wanting something simple and different that fits well and is dead nuts reliable in the long run. And the price was certainly right. Not looking for a ton of power either. Not a priority anymore.

Thanks
Codfish

Years ago, a friend of mine had a slant 6 and 904 in a 34 Plymouth Coupe. It was the shorter version of the coupe. It fit pretty nice, and went down the road really well.

Substantial difference between a 34 and a 37 Plymouth

I believe the slant 6 is a little longer then the original flathead was, and the firewall was inset to accommodate the flathead's length. Likely the slant 6 won't fit into the recess for the flathead because of the angle, but none of that may matter at all. We have no idea what was done to put the LT1 in the car. In addition, I have no idea how the length of the slant 6 compares to the length of the LT1, they may be the same length, but odds are better the slant 6 is longer then the V8.I would guess it depends on if or how much the 37's firewall has been modified to fit in the Chevy V8.

That probably wasn't very helpful was it....Gene

I never knew of a person pulling a v8 to put a /6 in but I can understand why. To have /6 rod would be cool and unique.

the engine bay difference between a 34 and a 37 is virtually zero. the body differences are another story.
figure on at least some firewall mods and of course, the engine wiring harness. if the GM engine has an electric fan, you may want to consider keeping that.
good luck on your project. keep us updated on the progress, please.

Ha, never even thought about the LENGTH of the /6

The firewall appears to be stock. It does have an electric cooling fan, which is a pusher so that will help with room fore and aft. As for the wiring harness, it has enough of the 95 Camaro harness to make the fuel injection work (ECM and sensors), but the starting and charging system is all tied into the universal aftermarket harness.

codfish

i owned a 38 coupe, and my one buddy owned a 37 sedan, plus, i parted out several 37/38 sedans. the firewall is indeed, stock on your car.
when the time comes for the mockup of the /6, consider replacing the pusher fan with a factory [OEM] style puller. since the 6 lays over, you may find by ditching the fixed fan and spacer, the firewall mods may be minimal, and the puller fan can be mounted high, missing the engine. as i don't have a /6 here to measure, i can't tell you the length.
although the original engine was a 6 as well, it may, or may not, be close. i'm saying this because the inline 6 was a heavy type of casting, while the /6 was a lighter, more "modern" style of casting, and may be very close to the original in size.
it was designed to fit in the new A body, and those had not only a lower hood line, but a somewhat cramped engine bay as well.
in the very early 70's, my one buddy had a T-bucket with a slant, and that thing would flat out scoot ! i realize that is an apples to kumquat comparison, but the cool factor was way high.

Roughly 30 inches.

Neat project.
Looking forward to the progression.

me too !

I get the dare to be different part but if you've drove that LS combo I'm thinking the slant might be a tad underwhelming.

Is a Gen3 Hemi a consideration? At least it's the same general shape as what is in there now and the trans is a Tremec so you could be just as all Mopar as a new Challenger when you were done.

Kevin

Huge difference between an SBC based LT1 (which is what he has) and an LS based LT1.

So it is Lol. Well that's a little closer power wise to a slant.

Would the SBC engine footprint be bigger than an LS? I'm thinking if it is it makes the Gen3 go in easier if there is such a thing as easier in this instance.

Kevin

Not that much of a GM guy but my understanding is that the LS is sever so lightly smaller in most respects than the SBC. But that really depends on what is dressing what.

Tunnel ram on a 350, it'll be taller, but stock intake vs stock intake the LS can be taller. No distributor on the LS so firewall clearance is better on an LS. Exhaust ports sit higher on an LS, so header clearances can be different. Oil pan choices are slimmer on an LS and not as easily cut and welded to clear. Not really a clear answer for you.

https://paceperformance.com/p-3990-engine-dimensions.html

The GenIII and various other Mopar engine dimensions

http://st.hotrod.com/uploads/sites/21/2016/10/54-Chrysler-engine-dimensionstable.jpg

i know engine height can vary a ton between installations, but the E58 360 i had in my coupe would have had no issues with running a tunnel ram under the stock hood with no modifications. it would have been CLOSE, but doable.
as i used a reversed corvair box on mine, i used a pair of 69/69 passenger side [center dump] manifolds from a 340 dart.
owning a junkyard back then helped with parts.
center dump headers were not available back then.

Thanks for all of the replies guys. I'll use what's under the hood for now to see how it runs. It was in the car when I got it. Haven't really driven it yet, only around the yard. No interior. That's what I'm working on now.

Out of curiosity, does a /6 and a small block share the same trans mounting bolt pattern? May have a lead on a cheap rebuilt 318 as well.

codfish

No on the bell housing pattern, for the most part. There is a bell the 60's trucks used that incorporated the rear motor mounts that had both patterns. It was for the NP435 truck 4 speed (granny first).

I also have a very vague recollection of a factory adapter plate that allowed the SB bell on a /6 in 60's vans.

in my junkyard ownership days, we had a 68, 3/4t pickup yard truck that was /6 - 727 powered with the dash mounted shifter.
it had the adapter plate for the small block pattern 727. it was the only /6-727 combo we ever got in. all the other truck/van automatics with the 6 were 904's. and we took in a bunch of 'em.

Every time I start looking or asking about stuff like this, I always feel that I was born 10-15 years too late. Might be different in the warmer climates where some vintage iron can still be found in the wrecking yards, but here in the north east it's all newer crap. I would have loved to own/work in a scrap yard back in the day, knowing what we know now.

the slant six bellhousing is its own pattern---if i lived in europe i would be tossing a 5 cylinder mercedes diesel in that and driving the hell out of it----in the 50,s the big dodges and desotos got sent to europe as taxis and they were fitted with small diesels-----by a diesel plant owned by chrysler then sold to cummins.....

in my owner days, we scrapped super bees, chargers, camero's, cudas , on and on and on ......... makes a guy [ME] feel guilty, but the object of the game was to make money.
we also scrapped old 30,s, 40,s 50,s stuff too.

the purests would kill us because we used fresh air hood air filter tops to stand on just to keep out of the mud !

however, we had no sixpak or hemi cars come in to crush, with the exception of a 58 imperial crown coupe, and a 57 imperial sedan, both having 392's. both of those engines reside on the rack in my garage.
we tried for years to sell the 58 as a resto, or custom project, but had no takers, so off to scrap it went.......

the stories i could tell of those days.

Can only imagine

I'm not a fan of brand-X motors in Mopars but pulling the bowtie in favor of a /6 is a step backward IMO.

It's not a done deal yet John.

I won't be pulling it unless what's there now gives me grief. Car has never been driven on the street since it was installed. It might be perfect as is. It's just that I came across the /6 and 904 for the right price, and was just trying to figure out any fitment issues.

Thanks
codfish

Free is the right price for a slant six.
R.

Friggin Newfie dare to be different!
Put an Aussie 265 straight 6 Hemi Six Pak in it!!
LOL!!
(I am from a city where they still make pulp n paper on the west coast on the Rock,LOL!!)

I'm gonna do what I'm gonna do regardless. Like I said it's not a done deal yet. IF the LT1 works fine, it'll stay. If not, it'll go. Slant 6 will work fine for me if I end up using it.

And Cab, I'm from C.B. too.

Small world hey by'? lol

codfish

Yes By'e!
Hey with the /6 when you park on a hill at home the motor sits upright!!
Withthe hills down home dropping the /6 will have a hard time climbing them compared to the LT1
Cheers!

out of curiosity, what year is that LT1 ?
my one buddy and i put a 95 LT1 in a 55 chevy here about 6-8 yrs ago, and i learned a ton of stuff i didn't want to know ! i got real friendly with the outfit that sold the conversion harness, but with their help, and a cadillac FSM i got from the local GM dealer, it turned out to be a nice setup.
had lots of power in that car [he isn't a drag racer, just a cruiser], and with a 700R4 transmission coupled with a 3.73 rear from a firebird and 255-70 tires [almost 28"diameter] pulled down 26 mpg easily.

Actually it's from a 95 Camaro, along with the 6 speed trans and the rear end. Stock ECM being used with enough sensors and relays to make it all work.

codfish

You can get tons of support here.

http://www.slantsix.org/forum/index.php?sid=d3b700c8b1d64038737c163433effaa3


Also with the slant, I would imagine you could straighten out that steering set-up.

I'll be following this.