Help with my '69 Coronet-- gearheads help me!

[Hohn]

Help with my '69 Coronet-- gearheads please help me!

Mopar guys, can you give me some pointers here on where to go with my Coronet? I want to have a car that's very powerful, but one that I can still drive to work every day without worrying about overheating and stalling and stuff.



The car is now a 318/904 car. I am weighing the options of big block vs small block, and to me, a big block seems to be the answer. I always thought the big blocks were a lot more expensive to build, but that parts costs are almost identical!



The main thing that scares me away from the big block is that I have never done an engine conversion before. I know that basically I will need a Schumacher motor mount kit, a 727 trans, and a shorter driveshaft. Is this something to be afraid of? I know that mopar swaps are about as easy as a swap gets (on B-bodies, at least)



I am gravitating towards a 451 low deck engine. Seems to be a great combo. The car will have a 3. 55 (or 3. 73) rear end, and a 9. 5 inch Dynamic converter. What cams have you run with good results? I presently favor an UltraDyne solid lifter setup, but am open to ideas.



This is my first real mopar project. I love the car and don't want to butcher it (even though it's already rough). Pump gas and daily driveability are realities I have to have. I think that 500 HP is easy to build in this engine, and another 150 shot of juice should be all the power I will ever need.



Thanks for your inputs.

HOHN

 

[Champane Flight]

Go

I would go 440, the Coronet came with a 440 in that year. It was a real sleeper. The 440 can be built with very little dollars to put some good solid horses to the ground, yet be very streetable. I like the lean side, mild RV cam, Edelbrok dual plane, minor head work, headers, mallory ignition, and Carter Afb with smaller primarys. With this setup on my old Town and country wagon, I could get 20+ mpg on the highway and 15 in town. All depends on how heavy your foot is. It would outrun tangs on the highway and give big block Chevelles all they could handle. This out of a BIG lumbering 10 passenger wagon! I would stay away from solid lifters for streetable cars. Have fun... .

 

[Philip]

For the B-body's in 69. Both small and big block used the same K member. This is the chassis componet that the engine and front suspension bolts to.



The engine mount brackets correct for that year are. #2863751

and 2536132. Those numbers are the orginal Dodge numbers.



The auto and stick use the same transmission cross member.



If you decide to go with a stick. Hit me with a PM. I have a B-body big block trans for around that year. In case you do not know. Small block and big block 4spd's are not interchangable. Each trans has a different front snout and bearing assy.



I would think on building an engine. 400 CI block. 440 crank and rods. If memory serves me right. You end up around 500 CI when your done.

 

[lgibson]

I would go with the 440 also. Because that year car came with a 440, it would be an easy swap with parts easy to find. I have a 69 4 door 440 Coronet that is stock. It is very dependable and streetable. My car has almost 150,000 trouble free miles on it.

 

[Hohn]

400 vs 440

Here's why I think that the 440 won't be best for me.



First of all, I can get a 400 pretty cheap, and the only 440s I know of, the guy won't part with. I know I could get a 440 if I REALLY wanted to, but there are a LOT of advantages to building the 451 stroker (LY rods, 440 crank, shorter pistons).



First, I am pretty sure it is 451 Cubes, just as if you bored a 440 out . 055". It's . 035 overbore in the 400. The 500 stoker others are thinking of is only with the mopar 4. 15 stroke crank. My motor would use the stock 3. 75 stroke 440 crank.



The 451 is everything the 440 is, but has many advantages. First, the low deck is a lot lighter than the RB motors. The shorter cylinders are more rigid, and better for a performance motor. The pistons are much lighter (about the same as a small block 360), so there is a LOT less strain on the crank and rods. In fact, the internals of the 451 weigh over EIGHT POUNDS less than a 440. That significant, since that's weight you are stopping and starting thousands of times a minute. Shorter pushrods in the 451 mean less flex and a more stable valvetrain. Also, the header clearance on the low deck motors is a little better.



Finally, the 451 doesn't really cost any more to build than a 440. The only extra is getting the crank cut (which you would have to do anyway). This is offset by the fact the the 400 core is cheaper to buy than the 440.



What hydraulic cam would you recommend? I was thinking one of the HUGHES ENGINES grinds would be a good choice, as they are ground specifically for the big . 904 Mopar lifters, and are a lot more aggressive. I might just use an off-the-shelf Comp Cams chevy grind, because they work and are proven.



The best part is that if I want to make this into a Super Bee, clone, I would pass off this monster motor as a stock 383, haha!



I think the Auto will be an easier swap for me, so that's what I am going to do. Who can I get to make a shorter driveshaft for me? Can I just get the driveshaft from a car that came with the 727 in it? Will the u-joint square up or did they use different yokes? What converter would you recommend?



Can I get decent power out of the stock 346 heads with some porting? Or should I just bite the bullet and get the Edelbrock or Indy heads? (there goes my DOR bumper)... ...



Wouldn't the 400 block bolt in the same as the 383? I was under the impression that a 400 wa basically just a bored out 383, with everything else (motor mounts, accessories, etc) the same.



If I am not mistaken, a 383 was also an option that year, and since I have the v-8 K member it should drop right in, right? Or won't it?





BTW-- the 400 I was looking at is out of a '73 roadrunner...

Thanks again, you guys are the best. I appreciate all the input I can get.



HOHN

 

[MCummings]

ABout the 727 Auto transmission,, You might want to give Bill Kondolay a call. He does trannies for gasoline cars too. From daily driver, to cars that only do . 25 of a mile at a time (As fast as they can)



www.dieseltrans.com



When I was buying a transmission for my Gas Drag Truck, I was gonna get a DTT transmission, complete with a full manual Valve Body, (Reverse Shift) and Transbrake, and it needed to handle a minimum of 400HP,, he gave me a good price, but a few hundred more than I could afford at the time,, But after all was said and done, Bill would have been the same price, and I would have gotten one good transmission from one good guy.



DTT, Do it once, do it right.



Merrick Cummings Jr

 

[Philip]

Your right on the 451 CI. It has been a while sense I did some research on this combo. (I was always a small block person in a Dodge).



The big block will drop right onto the K-member you have right now. Any of the engine mounting brackets from 1966 to 1970 will work. The only ones that won't are the A-body brackets. You can use B,C or E body(70 to 72). They are the same. So finding them shouldn't be to hard.



The drive shaft from a 727 car will work.



I would go with the stock heads. Just have the ports cleaned up on them. The only need for the Indy or Eldebrock heads would be for a Max HP motor. For every day driving like you asked for. The aftermarket heads are over kill.



On a cam its the same thing. To much is a pain. When you start running stall converters to get the car to idle. Then you build more heat in a trans that you have to get rid of. I would use the smallest purple stripe cam Dodge offers. I have used this cam in a small block before with out a stall converter. Or an aftermarket RV cam makes a good pick also.

 

[Mopar-muscle]

most of the thoughts are right on .



you can build a 451 for about the same as a 440 , the added expense will be finding a 440 crank and having the main journals cut down to fit the 400 block . depending on where you live this will cost from 100 to 300 .



by the way a 400 weighs maybe 20 pounds less than a 440 .



an alternative would be to get a 383 crank , will be forged steel vs cast of the 400 crank , get a set of nascar length hemi rods , manley has an H beam on sale right now , they are 6. 985 vs the stock 6. 768 with this rod you can use an off the shelf piston for a 400 with a 3. 915 stroke crank will give you a good rod ratio and a light piston ,and be a little cheaper to build than the 451 , bored . 035 over makes a 406(??) . just an alternative .



by the edlebrock heads , out of the box they flow as good if not better than a full boogey ported stock iron head to rebuild a stock set of heads with all new parts will cost about 700 , no porting down yet .



the crossmember from your 904 will work with a 727 , the 4 speed in 69 used a different crossmember than the auto's .



big block and smallblock trans in 69 , the difference , except for the hemi 4speed , is the bearing retainer , which is a bolt on swap . the trans is identical otherwise .



you will have to shorten your present driveshaft for use with either a 727 or a 4 speed , they will be the same length .



you will need a new engine wiring harness , throttle cable , big block radiator ,big block transmission , big block torsion bars and adding a swaybar is a good idea , upgrading to front disc brakes .



check out www.moparts.org for any and all questions you may need answered .

 

[Philip]

big block and smallblock trans in 69 , the difference , except for the hemi 4speed , is the bearing retainer , which is a bolt on swap . the trans is identical otherwise .

The bearings under those retainers are different sizes. The bolt holes are different width also. They do not interchange.



I found this out the hard way a few decades ago when I swaped a 340 Challenger from a auto to a stick.

 

[Hohn]

Wow!

I can't tell you how awesome you guys are!



BTW-- that 383 combo is one I haven't heard of, but that would give you a killer rod ratio (over 2:1)

I am starting to think that my BEST option is to swap in the 400 (it runs) and the 727 at the same time, then just get the thing running right. Then maybe later, pull out the motor and rebuild it the way I want it.



I can get this 400 cheap ($200) because it is "a dog" according to the guy that pulled it from the RR. All it took for me to love the 451 was a 10. 50 blast in a '68 coronet.



I knew about all the supporting hardware (i. e. stiffer torsion bars, fron discs etc. ) and those are good ideas. So here's what i show as needing to complete the swap alone:



1) motor

2) trans w/converter

3) Shorter driveshaft for 727 from another B body Dodge. Will the E body driveshafts work? Also, I think i remember that the Plymouths had a 1" shorter wheelbase, so is the driveshaft also shorter?

4) motor mounts or schumacher kit.

5) new headers (duh)

6) new engine wiring harness (available from Year One?)



I think this will come together nicely. If I CAN get a 440, I might just do that. We'll see what's available. Thanks again, you guys are now in my last Will and Testament



HOHN

 

[Champane Flight]

Used to.

Hohn, I used to have all my driveshafts done by the local machine shop. This was back in the seventies, but the price would be around $75. 00 for shortening.

 

[Mopar-muscle]

philip , depends on what YEAR AND TYPE transmission you were using ... .



up to 69 big and small block B body transmissions shared the same cases , internals and BEARINGS both front and rear only difference is the bearing retainer .



if you wanted to put an a body trans behind a big block using a big block bellhousing you can just swap the bearing retainer.



in 1970 chrysler changed around the transmissions some , different gear ratio for first and for the B/E body ( in 1970 they had one trans that coverd both , it had dual shifter mounting pads on the tailshaft and they also moved the trans mount so there was only one crossmember to deal with ) the big blocks used the same bearings as the hemi box , smallblocks used the same bearings as the 69 and down transmissions . but you can work around this if you know whats what .



heres a breakdown .



66-67 hemi box used the small 307 bearing , special retainer .



68-69 hemi box , larger 308 bearing , its own retainer



66-69 non hemi box big or smallblock , 307 bearing and reatiner that had a different register OD to go in its specific bellhousing



70-up non hemi big block , 308 bearing and a application specific retainer



70-up hemi box 308 bearing , application specific retainer



70-up smallblock 307 bearing , application specific retainer , you can swap on a 69-down non hemi big block retainer to use this trans behind a big block ,internals are identical to a big block trans



75-up OD trans , looks like a non od 833 , used a 308 bearing and had a special retainer with a larger than even the big block register for an application specific bellhousing . this trans could be put behind a big block by using the reatiner from a 70-up non hemi big block trans or any smallblock using the later OD non truck bellhousing .



did i miss anything ??? i've spent more hours than i care to think about wrenching on mopars musclecars , i have a 1969 dodge Superbee and a 1969 dodge dart GTS ,original 440 car , this one is a drag car i recently bought ...



heres the dart



http://www.moparts.com/~johnrr/



hohn , factory mounts , though i think that schumaker has them , but they may be more expensive , this mounts you need are a dime a dozen , the wire harness can be gotten from a number of suppliers , year one is probably the most expensive , try jacks , or the paddock , or bill evans in pa i think , he makes the harness' for the suppliers and he can make you one almost anyway you want it , want to run a MP electyronic ignition , he will graft it in , add a wire for an electric choke if you need that also and for a factory tach ...



driveshaft , just have your shortened unless you are switching u joint size . yes the plymouth b body has an inch shorter wheelbase and the e body and a body will be to short .

 

[Wayne M.]

Hohn, So far you've got a tasty recipe going here! You are dealing with good vendors here, especially Dynamic. I would stick to Hughes or Comp, and call them with your final draft of the whole car, and let them guide you in a cam, then get a converter. I guarantee that if Dynamic's Frank Lupo does your converter it will be good out of the box or in a worst case, it'll have to go back once (adjustment) to be perfect. I get my drive shafts shortened at a local machine shop, and new ones from a full service machine shop who is a Spicer dealer. There is a method to determine proper length, if you dont have a "Chassis Bible", PM me and I'll outlone what it says.



There are 3 things I would do to make the car awesome;

1) if you want personality (the sound) and don't mind cracking the valve covers occasionally, go solid cam!

2) This car HAS to have EFI!

3) change to dual field charging system



Good luck.

 

[Mopar-muscle]

wayne , good point on the charging system .



hohn , i'll get you bill evans number tomorrow , i had him make my harness with the dual field system , you need to get the regulator bracket off a 70 b body and when you are done it will look like a factory install .

 

[Wayne M.]

Yep, Bill & Rose Evans. That's who supplied a custom harness for a 440 into a '74 E body install I finished recently. They did a real good job, even kept the seatbelt starter interrupt system.

 

[Mopar-muscle]

evans wiring website

sorry for the delay . .



check here . .

http://evanswiring.tripod.com/evanswiringharnesses/index.html