Re: '66 Dodge D-Dart at Mecum auction
 

Check this out


http://www.cometeastcarclub.org/Comet_HIPO_65.html

Re: '66 Dodge D-Dart at Mecum auction
 

Alan,
Nice Comet. Putting together some detailed specs. for the D-Dart. Will post later. As for the 7 1/4" 1965 rears. Gear ratio's 2.76....2.93....3.23....
3.55....3.91... for the Hotchkiss Drive. Not sure if anyone made steeper gears...But, the 1965 Cuda "Goldfish" of the Hamilton Motors "Golden
Commando's" ran In F/Stock in 1965 (12.50 - 13.99 wt/hp break). Won
the F/S class at the 65' NHRA Nationals. And, held the F/S record with a
13.44 @ 103.68. Ran 4.89 gears, in an 8 3/4" Sure-Grip/Posi. They went AHRA in 66'.
Paul

Re: '66 Dodge D-Dart at Mecum auction
 

Alan,
The D-Dart engines were assembled at Chrysler Industrial. Though the
Camcraft camshaft is stated as a .495/.505 lift, in actuality it has a lift of .504 Intake / .515 Exhaust....
According to NHRA technical, the intake and exhaust valves on both
the 66' D-Dart and standard 273/235HP Commando engines are the same size. (1.78 intake) and (1.50 exhaust)...The cylinder head chambers were measured at 57.3cc... Currently (5) different casting # heads can be utilized, all with the same valve size, #2455315,,#2658920,,#2843675,,#3671585,,#4323302.. The intake port sizes equal 1.70 sq. inch and the exhaust port 1.25 sq. inch.
Paul

Re: '66 Dodge D-Dart at Mecum auction
 

They went AHRA because NHRA disallowed the 8 3/4 rear in the 65 Darts and Cudas sometime after the Winternationals until a few years later and it was allowed in AHRA. Someone pointed the fact out about the 8 3/4 rear not being assembly line produced in cars like Golden Commados car to NHRA officals after the Winternationals. Of course NHRA never caught the acid dipped front fenders and hood......LOL.

Re: '66 Dodge D-Dart at Mecum auction
 

Paul,
According to an old parts casting book that I have, that Galen put out, the 2658920 cylinder head castings for 1966 had 1.87" intake valves --- P/N 2536176. In 1967, the same castings had 1.78's --- P/N 2806213.

The cars were built on April 17th. The engine ID boss on Politician engine is stamped either R-273- 4-27 or it might be B-273- 4-27. The one on the Mecum car (my old car) was stamped R-273- 4-26 or B-273- 4-26. The bottom portion of the B or R is missing. If the 4-26 and 4-27 are the dates the engines were built. Where, when and who installed them?

Here's a picture that I got from the D/Dart web site moderator. It's of the Porach D/Dart when they first got it. I had asked them about the headers, hurst shifter and possibly a Sun tach being in the trunk at the time of delivery. It's definately an Inland shifter. You can caption it as you want.

Re: '66 Dodge D-Dart at Mecum auction
 

The 8 3/4 rears for the darts and Barracudas were actually approved by NHRA for stock on 17 August, 1965

Re: '66 Dodge D-Dart at Mecum auction
 

I'm curious as to whether a 1.87" intake valve would clear the cylinder wall on a (small-bore) 273 without relieving some of the material from the cylinder wall.

Might that be a factor?

Re: '66 Dodge D-Dart at Mecum auction
 

Here is a picture of the copy of the letter that NHRA sent out on the 8 3/4 rear. The actual reason that the factory started putting the 8 3/4 in the 65s is that owners of the 4 speed cars were destroying the 7 1/4 rears. Ma Mopar got tired of replacing the weaker rear under warrenty. Not all the 4 barrel 273 cars got the 8 3/4, only the 4 speed cars.

Re: '66 Dodge D-Dart at Mecum auction
 

Alan,
What you said does make sense. 8 3/4' for 4-speeds, and the 7 1/4" for automatics in 65'. I would imagine many of 65' 273 Commando 4-speed
Darts and Cuda's in early 65' never drove home from the drag-strip. Got brought home via a chain.
I will post some valve clearance info. You have to check the photo's of the cylinder head (valves and combustion chamber) in the Ted Spehar
Dart, on the D-Dart site. Those intake valves are not 1.87". They are definitely 1.78. On the bottom side of the head, a "2" is stamped within the indentation. Not sure if that indicated anything special.
On the engines, again put together at Chrysler Marine & Industrial.
Paul

Re: '66 Dodge D-Dart at Mecum auction
 

I couldnt remember exactly when they were approved but knew it was late in the 65 season. Thanks.