The 400 Mopar is an interesting engine. The
bore is the largest of all Mopar engines even bigger than the 440 at 4.340".
The stroke is the same as the 383 at 3.380" One of the more popular swaps
was to put a 440 crank into a 400 block and wind up with a 452 cu in big
block. My friend Gary Wager asked if we could do that to his 400 in his
82 Mirada. To make a long story short we got carried away. It seemed to
me that the 452 was not enough of a gain for the expense involved although
I readily concede they are a very successful combination. We decided to
go a bit further and had a 440 crank machined to fit the 400 block and
offset ground the crank to 3.780" stroke (.030"). We bored the block .060"
oversize to 4.400" bore as pistons are readily available in that bore for
the 400 even from Mopar Performance. With a bit of flogging we machined
a set of pistons to clear the 440 crank and we remachined them for valve
reliefs and deck height. A Lunati hydraulic cam was installed along with
the usual iron heads with 2.14/1.81 valves. A Wiend Action plus was installed
along with one of my reworked 750 Holley carbs. We loaded up and went to
Cayuga Dragstrip for their all Chrysler meet. First pass on the car right
off of the trailer was 11.86. Within about three weeks Gary had it
running 11.20 at over 123mph. Eventually he got it down to 11.0s at 124.95
mph after installing a Racer Brown cam. The 11.20s were run with an hydraulic
cam and several were run on the stock stamped steel rockers. When
he got the chance Gary swapped them out for a set of reworked Isky adjustables but to be truthful they never gave a second's trouble. This engine was written up in "Chrysler Power" in July 97 and was called" $1500 Econo Big Block." The title I gave it when I wrote the article was "All The Wrong Stuff." That is because we built the engine using factory cast piston cores and a cast crank. At the time we both knew it was an experimental engine and we didn't know if it would work so we didn't want to spend too much on it. It reality did cost only about $1500 US or $2000 Can so that is why the magazine renamed it. As it turned out he raced it several years with no problems. We redid the engine a couple of years ago with Ross forged pistons and the usual modern hi-tech stuff. Did it run any faster? NOT A BIT! I still have the original reworked cast pistons and 400 rods. They are still in perfect condition despite the many hard passes they have made down the quarter. Gary has been reworking the chassis to improve his short times as a 82 Mirada is hardly a race car by anyone's definition. He is looking forward to running in the tens this year. Where is the reworked cast iron crank you ask? He is still using it in the new engine as it was so perfect he couldn't bring himself to replace it. I guess he is right because no matter what your personal opinion may be there is no way to argue with success!
Here is the engine just before Gary installed it. The Thermquad was just for the photo although he did run it a few years later. It could never touch the reworked Holley 750 however.
Gary rolls out of his burnout and stages at Shannonville Dragway. This is low buck racing at its finest. In the other lane is a 500 cube big buck engine that while competitive caused no serious threat to Gary. Its not the price of the stuff but the science behind it that makes a car perform!
big-d Garys page link