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The History Of Big Block Mopars

by Dawg

Mopar Big Blocks

How about a 350 cubic inch engine for your Mopar? Sounds like heresy, doesn't it. Has a kind of General Motors ring to it. Would you believe that this could be true, be a big block, and be a Mopar? This article... will deal with the progression of the big block Mopar and the common parts associated with each family.
The 350 cubic inch engine was introduced in 1958, as a purely passenger car engine. The performance engine was the same engine with the bore increased .060, which became the well known 361. This engine reached significant performance proportions in the 1959 model year. The 1959 Sport Fury with the 305 horsepower 361 was a formidable street vehicle. The same engine was also available in the Dodge.

The first 383 was introduced in 1959, but as the raised block. The dimensions on this engine were a bore of 4.030 and a stroke of 3.750 inches. This engine was available with two four-barrel induction and a horsepower rating of 345 @ 5000 rpm. The following year retained the raised block status of the 383, but introduced the outrageous long ram aluminum manifolds. There is some confusion over the long and short terms and the availability. The manifolds were dimensionally identical. The difference is internal. In the long ram, the Siamese tubes are separated by a continuous wall, the entire length of the runners. In the short ram, the term short refers to the divider wall, which extends only 10 1/2 inches from the cylinder head surface. In other words, the terms long and short refer to the divider wall, and not the length of the tubes. All passenger cars had the long ram configuration. The short ram was available over the parts counter. The long rams were for low and mid-range RPM applications and the short ram was strictly high RPM and performance on the track. This system was offered again in 1961. Let's take a look at the numbers. The long ram 383 produced 330 horsepower at 4800 rpm, with a torque reading of 460 ft. pounds at only 2800 rpm. The short ram 383's numbers are 340 horsepower at 5000 rpm, with a torque reading of 440 ft. pounds @ 2800 rpm. The differences are minor, but the drivability was major.

The 383 was converted to a low deck configuration in 1960. It was now a 4.250 bore with a 3.380 stroke. The highest horsepower 383 featured the 300J heads, with two four-barrel induction, and a horsepower rating of 343 hp. This combination was offered primarily in the big cars, but was available over the counter through 1962. There is an NHRA class engine for the 1962 B-body Plymouth and Dodge listed in the 1962 rule book for this application. Research into this engine has shown that the 1962 B-bodies with this option were ordered as 383 four-barrel cars, with the induction system (manifold, carbs, linkage, and football shaped air cleaners shipped in the trunk) dealer installed.

The 383 remained a strong performer through the mid 60's, but the performance image had shifted to the 413 and 426 wedge and max wedge programs. The incredible 426 Hemi was on the horizon, but the low deck engines were far from the scrap heap.

The advertised horsepower ratings of the 383 were actually lowered in the mid 60's, in order to highlight the performance aspect of the RB engines. The late 60's performance spotlight returned to the 383, with the introduction of the Plymouth Roadrunner and Dodge Superbee. The 1967 year is very significant in the development of the 383 as an image engine. This is when the high performance 440 was introduced in the first badge identified B-bodied performance cars. The GTX and the R/T featured the high compression, big valved, hot cammed, dual exhaust, unsilenced air cleaner, 375 horsepower earth-moving 440 HP. The market in 1968 demanded an affordable musclecar. The hot 440 parts would bolt right on the 383, and Chrysler had built millions of them. Cheap to produce, bullet-proof, and possessing outstanding performance, the 383 embarrassed a lot of 440 owners. The short stroke engine with the proper gearing was a performance and sales success.

The 383 was gradually detuned, as all smog motors were, and in 1972 it was replaced with the huge bore (4.340) 400. Do not overlook this engine as a performer. Think of it as a big 383. Lots of cubic inches in a relatively small package. Lots of options on the performance list. There were over 3 million 383's produced through 1971 and they are still relatively easy to find. The 400 blocks are very common and will bolt in anywhere there was a big block engine. The 400 is externally balanced and requires the correct damper and torque converter.

The last installment dealt with the low-deck engines and the natural progression of the displacement variations. This time we will talk about the raised block versions of the big block Mopar. The 413 wedge was first introduced in 1959 in the Chrysler nameplate and 1961 in the Plymouth and Dodge lines. The bore and stroke measured 4.180 x 3.750. The engine was rated at 350 horsepower at 4600 RPM and 470 ft. pounds of torque at only 260O RPM. The long ram version produced 375 horsepower at 5000 RPM and 465 ft. pounds of torque at 2800 RPM. The higher horsepower was at the expense of low end torque.
1962 was the year that stands out in the minds of true performance enthusiasts. Described to this day as the Magnificent Max Wedge, the 413 Max Wedge motor raised the bar for performance. Truly a drag strip only creation, this engine featured the following significant parts:

* Unique heads with 25% larger intake and exhaust ports
* No heat crossover
* 2.08 intake valves and 1.88 exhaust valve size
* 510 lift mechanical camshaft with 300 degree duration
* Special tubular pushrods
* Dual valve springs-and nodular iron adjustable rockers
* One piece ram induction manifold with 15 inch runners
* Staggered dual Carter AFBs with 650 cfm each (3447)
* 11.0 or 13.5 TRW forged pistons
* Forged and magnafluxed rods
* Cast iron headers
* Deep grove pulleys
* Special baffled oil pan and custom swinging pickup

The 1962 Melrose Missile was the first production passenger car with a factory option engine into the 11's. Tom Grove ran an 11.93 @ 118.57 on July 15th, 1962.

The Max Wedge 413 was dropped in 1963, but the 413 displacement engine soldiered on until 1965 in the Chrysler models. A dual four barrel version was available throughout 1964.

The 426 wedge engine also appeared in 1962, but was only installed in the top of tile line Chrysler models. The Dodge and Plymouth debut was saved for 1963 and it was special, the Max Wedge 426, Stage II. The primary difference was in the bore... which was enlarged to 4.25 inches. While the books show that the Stage III engine was not introduced until the 1964 model year, this is not entirely true, based on my own personal experience. The Stage III appears to have been available in late 1963. The Carter AFBs were changed to the 3705 number and offered a higher CFM rating. The basic difference is that the 3447s have four venturis with the same size, or 4 equal holes in each carb mounting flange. The 3705ís feature larger secondaries, with tile original size primaries. It does appear to be a common performance improvement for the Stage II engines to have the carb mounting flange enlarged to accept the larger carbs. The camshaft was increased to 520 lift and 320 degrees of duration on the Stage III engines. There was a new cast iron header offered which was referred to as the Tri-Y.

The street wedge was offered in 1964 and 1965, rated at 365 horsepower and 470 ft. pounds of torque. It was a single four barrel engine of conventional design and street application.

1966 found the 440 cubic inch engine offered in the big car passenger line. The engine was offered in two versions: 350 horsepower @ 4400 RPM and 365 horsepower @ 4600 RPM. Both engines developed 480 ft. pounds of torque. Neither engine was considered a performance engine. With a bore of 4.320 and the long 3.73 stroke, the performance image of the largest displacement engine ever installed in a Chrysler Corp. vehicle was about to change. The Super Commando, Magnum, and TNT pieplates were installed in 1967. The high lift cam, modified exhaust manifolds, hi-flow closed chambered heads, increased exhaust valve size, dual exhaust and the R/T & GTX nameplates spelled trouble for the competition. 375 horsepower @ 4600 RPM and 480 ft. pounds of torque at 3200 RPM. Chrysler had a winner. The 440 high performance engine fit very nicely between the 383 and the 426 hemi. With the addition of the 6-pack induction in mid 1969, and the 390 horsepower rating, the 440 with the right gearing was nipping at the heels of the hemi. By 1971, the 440 was beginning to suffer from emissions, mileage, and other corporate ailments. The 1972 brochure does show the 6-pack option, but few, if any, were produced. The engine stayed in production until 1978, and the last 440 was offered in trucks and motorhomes.

Recently, one of the Mopar magazines asked the trivia question... Which engine has been produced in the most displacement sizes, the low deck or raised block? The correct answer is the same number. Tile low deck variants have been the 350, 361, 383, and 400. The raised block... 383, 413, 426, and 440. The raised block 383 is basically non-existent, but was built.

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