Thread: 413 to 426

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I was wondering if I could punch out my 1965 413 to 426 or 383 bore(4.25)

TECHINSPECTOR1, WHERE ARE YOU?

Well, Psycho, In the absence the authority, I dug around in the big mess I call "my files" and found some information that may be helpful.

Your 413 came with a bore of 4.190, so you would have to go .060 over to bring the displacement up to 426. The 426 is fairly similar to the standard 413 but it was cast "beefier" to allow for the larger cylinders.

If all you want is an additional thirteen cubic inches that would get it, but to make the engine feel a little more like a 426 you'll need to think seriously about the heads, because they are probably the biggest difference between the 413 and the high performance 426. The intake and exhaust ports are 25% bigger and the opening for the exhaust valve is 1/4" larger than in the 413 head. The intake valve is the same as in the 413 (2.08) but the exhaust valve is a quarter inch bigger, and the heat crossover passage was eliminated.

From what I can find out, the best heads ever made for these engines (next to the "hemi" heads) was the '62 "Max Wedge" head; 2.08 intakes and 1.88 exhausts. I wouldn't bother to look for any. If you found some you'd have to mortgage the farm to pay for them.

HOWEVER .... the next time you're scratching around in Honest Andy's wrecking yard, look for a '68 through '70 383 or 440 with a four-barrel carburetor on it. Their heads have the usual 2.08" intake and a 1.74" exhaust. They flowed air well enough that they were used on the Roadrunners and 440 Magnums of the era. These are called "906" heads. To make sure you have found a set, take off a valve cover and look for a casting number on top of an intake runner. It should be a seven digit number the last three of which are "906". They are reputed to be some of the best high performance heads Chrysler ever produced.

Jim

my buddy has a 426 max wedge sitting on a engine stand that he payed payed $900 for the motor and the 4 speed , i have ben trying to git that from him

Hey thanks big. I was wondering about the mains in the bottom end, If they would hold the power or not. But I think I'll go with the .10 to .20 over and play with that. I'll be putting this monster in a 91 dakota prostreet.
Thanks for the info.
Don

Sounds like the way to go, Don.

Regarding the mains, you should be okay. I don't see that the 426 ones were different from those in your 413.

If the crank in your '65 engine is original, that's a plus. Up until '71 the 413's had forged crankshafts. After that they were cast. The forged type is considered to be a much better crank. If there's any doubt as to whether you have a forged crank, look at the counterweights. Forged ones have rounded off edges. Cast ones have sharper corners.

And, as I suggested, look around for a set of the 906 heads. They shouldn't be very expensive and I'm told that they are superior to the standard 413 items. BUT.... take a little care here..... if you are able to go with the 906's you may have to get your friendly machine shop man to notch the top of each cylinder bore just a little to provide clearance for the larger exhaust valves.

A lot of guys like the 413's. I bought a '70 Dodge 3/4 ton back in the late seventies and somebody had replaced the original 383 with a 413. That was okay with me, but it had one zero compression cylinder and one that was so close to zero that I'll call that one zero, too. A friend wanted a 413 badly enough that he traded even with me for a good-running 383 and he even did the swap for me.

Feel free to send me a PM if you have questions. I'll see what I can find out for you.

Jim

i also just came across a motor home with a 413 in it for free , i was just wondering if it would be worth it to just drop the motor in my cuda just for now or if their is any mods that i have to do to fit the 413 in it , i have ben told i have to motch the cross member for the oil pan , that all i have ben told , also good luck on the 413 build up

Say, Fish, Judging from your user name, I'm assuming that your Barracuda is a 1972 model. The '72 was not offered with a big block engine (at least I don't think it was) so installation won't exactly be a drop-in. It could be done, but there would be a lot more involved than modifying your cross member.

Jim

no i just got all the info on what i gatta do , and yes my car was offered with a big block , all i gatta do is change the motor mounts and trim the cross member if im ganna run a over sized oil pan , my car had the option of a 318 ,340,360,440,400,and no hemi ,unless you wanted it to pay big extra for it

The 426 wedge (426W) was nothing more than a large-bore 413, but the maximum recommended overbore is .040" on all '58-up Mopar engines (except the Polysphere 318-based engines and supposedly Slant Sixes). Both the 413 and the 426W share rod length and main/rod journal sizing with the 440, as well as the deck height (10.72"). The vast majority of 440 speed parts will fit the 413 with the obvious exception of pistons.

Passenger-car 413s used a different lifter height/pushrod length than 1968-up 440s, but it's the same as 426W and 1966-'67 440s. It doesn't much matter, though, since as long as you swap pushrods and lifters at the same time, it's a direct swap. Virtually all aftermarket pushrods and lifters are now the '68-up style.

Early (pre-'62) 413s used an oddball 8-bolt crank with no flexplate/flywheel register (centering ring) but the common 6-bolt piece used later is a direct swap so you can use commonly-available flexplates and torque converters.

All 1968-'70 big-blocks used the famous 906 casting, even the two-barrel 383s. All used the same 2.08"/1.74" valves, too--there is no difference between HP heads and base 2v heads except the valvesprings (and in some cases, retainer style). The last year for a specific HP casting was 1967, in which the 440HP got its own specific head, the closed-chamber 915.

An even better choice is the later '70s 452 castings, which flow better than the 906 out of the box (after 1968, all Mopar B/RB heads have 2.08/1.74 valves), have the same maximum porting dimensions, and already have hardened valve seats for unleaded gas. There are millions of these sleeping under the hoods of 400 Cordobas in junkyards.

Motorhome and truck 413 engines usually have different heads than passcar engines; they have extra water jacketing around the exhaust ports and will not accept passcar headers or manifolds. They also use a unique intake, which is not a worthwhile performance piece, and many of them had 8-bolt cranks with a proprietary conveter/flywheel hub length. Plan on using only the block; virtually everything else needs to be replaced right down to the water pump housing. Put yourself way ahead of the game and just find a 440... it'll be cheaper in the long run, and have more CID in the first place.

1972 Barracudas and 'Cudas were only available with Slant Six, 318, and 340 engines... all big-blocks were discontinued after 1971 in E-bodies (Barracuda/Challenger models). No '72 anything was built with a Hemi, and less than a dozen Six Pack 440s got out (in Road Runners and Chargers only) before that plug was pulled as well.

You couldn't even get a Tilt Six E-car after '72, the '73s being 318 or 340 only and the 340 being replaced with the 360 in '74 (also, E-body production ended early that year, never to resume).

However, the E-body non-Hemi V8 K-member is the same 1970-'74 (the '70-'71 440 Six Pack models had a skid plate, but were otherwise identical). The only change necessary to bolt the big-block to a '72-up car is the motor mount brackets which bolt right to the engine lugs--the mounts themselves (the rubber parts) are the same, be it 318 or 440+6. The big-block also requires its own transmission--a SB unit won't bolt up--and the radiator probably needs to be changed or have the hose fittings moved, depending on what year water-pump housing is on your big-block. The lower hose inlet moved to the opposite (passenger) side in '73. Plan on new exhaust, as manifold outlets are located differently between big and small-block, and obviously the manifolds themselves won't interchange between engines. If your car currently has a 904 transmission, you'll need a shorter driveshaft, too, since the required 727 is consderably longer than a 904. No, Barracuda and Challenger driveshafts don't interchange--the Challenger has a 2" longer wheelbase. The 6-quart "Hemi" pan will clear any factory V8 K-member without any trimming, and don't forget to extend your distributor wiring--the big-block distributor is up front.

Hope this clears up some confusion and maybe prevents someone from buying the wrong engine.

You reading this, Psychoward and Wildfish72?

And ..... Hey, Doc! I was hoping you would check in. Thanks!

I appreciated your posting on small-block heads. I printed it off and put it with my aforementioned "files".

And thanks for bearing me out regarding engine availability for the '72 Barracudas and Challengers. I was relying on my ever deteriorating memory on that one, and I based that assertion on the fact that I bought a '70 Duster new, then a couple of years later I went back to talk to my dealer to discuss trading for a '72 440 Barracuda. They couldn't sell me one. Just as well, I guess. I went home and kept the Duster for thirteen more years.

Tell me something not engine related: Will the torsion bars in Wildfish's Barracuda be adequate? Or are they adjustable to the extent that they can accommodate a big block? I have wondered about that.

And how about his cooling system?

Your comments are appreciated.

Jim

OOPS .... I see that you addressed the radiator situation.

Jim

The torsion bars will hold; in fact lots of racers use Slant Six bars to aid in weight transfer... but I wouldn't want to be caught on a mountain road with anything less than the factory big-block bars up front on a mountain road (all E-body T-bars are the same length, shared with '66-'72 B-car bars).

Without a swaybar, I wouldn't even pull it out of my driveway.

As far as the radiator, I consider a 26" 3-row mandatory... but if you can make a big-block stay cool with a 22", good for you. Too many years in the Atlanta heat taught me that the 22" rad just won't do. My current preference is to cut the core support to accomodate a '78 360/AC truck rad, resto-correct be damned. When using the early big-block water-pump housing, moving the lower outlet is a cake-walk for any competent radiator shop.

Interesting side note on four-row radiators: According to Chrysler factory testing, the fourth row so many hold dear actually picks up heat from the first three rows, and therefore is a complete waste of time. Plus, it adds its own weight as well as that of the extra cooler.

Hey that was some good reading. Thank! I have a 197? 400 so Iam going to check the heads out. Just maybe. Thanks for all the info. It really help to find this stuff out before I go doing something stupid with the block. You guys are like wizards. Thanks alot.
Don

i have a alum rad, noo need for any of the others , and this car is ganna be set up for strait line , but im not ganna put a big block in it anymore , ill be better off with my 408 stroker ,

[QUOTE= im not ganna put a big block in it anymore , ill be better off with my 408 stroker ,[/QUOTE]

Wise move. Should save you a lot of grief,

Good luck with it.