Now that the individual systems and special parts have been covered, we can try to put them together into a complete engine package to go racing. Be sure to refer to earlier sections for further details.
A. NHRA Stock
Stock Eliminator is the best place to race the slant six in class-type racing. The best classes are U, V, W, X/S.
The fuel system should be one Carter electric fuel pump PN P4007038 at the rear and one standard mechanical pump on the engine. The oil system should use the stock pan with an acceleration baffle added along with the windage tray set 1/8" from the rod bolts and crank.
The high output electronic ignition is the best ignition for racing and the .040" wide gap plugs should be used.
The 1-5/8" primary tube headers should be used. A "cheater" or "blueprint" camshaft is a must. They can be obtained from Competition Cams, Crane, Lunati, etc. The stock valve spring specifications must be met. See Bulletin #35 for further details.
B. NHRA/IHRA Super Stock Racing
The best choice for racing the slant-six in NHRA/IHRA Super Stock competition is the 1960 HyperPak Valiant. The four-door sedan fits into SS/U. In NHRA competition 17.0 pounds per horsepower is the lowest class. If lower classes were used and the current 75# rule is in effect, the sedan also makes a good car in the 18.0 class and the wagon fits well in the 19.0 class.
The original Hyper-Pak four barrel manifold is probably the best bet for intake manifolds. Refer to Chapter 21 for jetting information.
A good camshaft choice would be an DC-276 P4286681 as a baseline step and progressing to an STX-22. Both cams are require special valve springs and retainers which are available from the 340 racing program. The part numbers are mentioned earlier and they are available from the Direct Connection Program.
The minimum head volume is 52.3 cc. The HyperPak has domed pistons for higher compression ratio. The dome height is .250" above the block and the dome volume is 13.7 cc. These special domed pistons should still be available from Forged-True. The electronic ignition should be installed on any Super Stock engines. This conversion is covered in an earlier section. The all-out Super Stocker should use not only the electronic ignition distributor, but also the Multi-Spark conversion as well.
NHRA/lHRA Legal Specifications
Min. Max. Head Engine Head Dock Milling Disp. Vol. Height Spec's ---------------------------------------------------------------------- 1960 Hyper-Pak To reduce the chamber 1963-71 225 53.8 - .141 volume, remove .0066" 1970-71 198 53.8 - .0765 from the head surface 1963-71 170 53.8 + .000 per 1cc. of chamber 1972-71 198 54.0 - .075 volume. 1972-75 225 54.0 - .140 1976-83 225 54.0 - .115
*Dome displacement 13.7 cc.
C. IHRA/AHRA Formula Stock Racing
A two-barrel manifold with carb should be installed along with a set of headers. The camshaft should be a D.C. P4286681 - 276 degrees. The good valve job and a .090" head mill (to approximately 45 cc.) should be done and the 340 valve springs installed. The electronic ignition system should also be used. It is important to build a good deep sump oil pan and modify the oil pump pick-up. We also recommend installing a windage tray. A fresh air hood scoop should be added - It is important to seal the carb to the head scoop. (See Figure 2-11.)
D. Sportsman or Circle Racing
The 1/2 mile or so circle racing groups have many different rules, but most have a special class for the 6 cylinder engines. Where the rules allow the top two barrel carb, the above Formula Stock package will work well. The top ring gap should be on the high side (.015) and a special oil pan and pickup will have to be used. The P4286681 cam, the 340 race type valve springs and pushrod kit should be used along with Gold Box P4120600 ignition system.
E. IMSA Sports Car Racing
The IMSA Sports Car Series for small, lightweight compact cars accepts the 225 Feather Duster/Dart Light as legal packages for this class. The 225 engine with 4-speed transmission would make a very competitive car in this class using much of the "Chrysler Kit Car" science.
F. Bracket Racer
In Bracket Racing low cost and reliability are very important. Here the slant six really shines. The two barrel and the P4286779 cam make a good racer package. The electronic ignition and the windage tray are also recommended. Refer to the latest Direct Connection catalog's 6 cylinder section for more bracket racing tips or Chapters 31 & 33 later in this book.
G. Four Speed Manual Transmission Installation
There is a lot of interest in installing the Chrysler four-speed behind the slant six. The original pieces used in '64-66 slant six four-speed packages are no longer available; but, the '75-77 pieces will work fine. The bellhousing PN 3743645 will accept the A-833 Chrysler 4 speed, but it has a very large transmission pilot diameter. The 340 transmission has the small drive pinion bearing and can be used in the six's bellhousing by using the special drive pinion bearing retainer PN 3878596. If the overdrive transmission is desired, it uses the special retainers so that it doesn't need to be changed.
There are two overdrive transmissions, one with a cast iron case PN 3878005 and one with an aluminum case PN 4028477.
Special Note 1: Many part numbers listed in this chapter are given for reference. They may not be currently available.
Special Note 2: The information listed in this chapter is more up-to-date than any other recommendations. Therefore this chapter supersedes all previous 6 cylinder engine bulletins and books.
Back: Special Car Packages
Slant 6 Index