D Dart spec. Anyone build one?

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MassDart

MassDart

Lifelong Dart fan
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So I'm most likely going to use the Isky E4 cam with Doug's headers and a Holley 4160 on my Eldelbrock LD4B upgrade in the spring. But I'm just curious. Has anyone built a D Dart clone using the 284 degrees with .495 intake and .505 exhaust spec cam they used in the D Dart? Is it streetable? Is it usable in a flat piston 273?
 
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Isky T-3 is the cats' A$$ with dome pistons .

my commando CAM specs.jpg


my coammdo CAM Specs II.jpg
 
I'll probably go with the E4 kit (which just jumped another 100 bucks in price this week). I was just wondering if there was anything out there that would get close to D Dart spec but with the low compression pistons.

Performance wise, I think I'll actually be better served if I can get my hands on 3.55 or 3.91 years for my 7 1/4 SG than trying to put a giant cam in.
 
MassDart said:
I'll probably go with the E4 kit (which just jumped another 100 bucks in price this week). I was just wondering if there was anything out there that would get close to D Dart spec but with the low compression pistons.

Performance wise, I think I'll actually be better served if I can get my hands on 3.55 or 3.91 years for my 7 1/4 SG than trying to put a giant cam in.
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The D Dart 273 ran 10.5-1 compression, the big cam, stock intake with a bigger Holley, and headers. They also used 4.86 rear gear along with the 4 speed. They ran 14.30's @ 92.
 
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On the up side, I found 3.55 gears on Summit thanks to a FABO member tip.
 
Yeah when I was young I saw a D-Dart motor that was being put together short block saw my first dome Pistons on a fresh machine block it was so cool. I think the big secret to the D-dart or one of them was the compression without that you're not really following the recipe.
 
K.O. SWINGER said:
Yeah when I was young I saw a D-Dart motor that was being put together short block saw my first dome Pistons on a fresh machine block it was so cool. I think the big secret to the D-dart or one of them was the compression without that you're not really following the recipe.
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Stock 10.5/1 pistons were used. They probably switched banks for less drag (because of the offset)

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It's a Sure Grip so it should hold together okay for the hp, I'll be putting through it.
 
MassDart said:
It's a Sure Grip so it should hold together okay for the hp, I'll be putting through it.
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Or not, depending how you drive it and the level you abuse it. The units are quite tiny (gears, carrier and bearings) and can't stand much abuse like side stepping the clutch, power shifting, or power braking a automatic. Just sayin.
 
As it is right now, it's really tight. Super clean, backlash feels right. But...if I wanted to lay in supplies for what apparently is the inevitable, are spiders for a SG available (are they the same as the open's)? How about bearings and seals?
 
didn't the original "D" Dart come equipped with a 4.86 SG 8-3/4"? and it was a little bit lighter...I guess as long as the tires spin, the 7-1/4 will last.
what about a 3.58" or 4" stroke crank in the 273? keep a more street friendly gear and have all sorts of low end torque.
 
abdywgn said:
didn't the original "D" Dart come equipped with a 4.86 SG 8-3/4"? and it was a little bit lighter...I guess as long as the tires spin, the 7-1/4 will last.
what about a 3.58" or 4" stroke crank in the 273? keep a more street friendly gear and have all sorts of low end torque.
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See post#8

A 4" stroke is like 336 cube. (I don't have my calculator program handy) Pistons would have to be custom made. If I owned a D Dart and thought I wanted more power I would pull the original engine, set it in the corner and build a 390 or 408 stroker. Naw, I would leave the 273 in there.
 
I currently own 2 real D/Darts. I had another one (the one that's been on the auction block 10 times) that I installed a 2 barrel motor with the Mopar Performance P-4452761 cam and lifter package in it. It was a .450/.455 hydraulic lift cam. Also installed were an Edelbrock Torker intake, a Holley carb off of a 383 Mopar engine and a Mopar electronic ignition kit. Not sure of the carb part number. It had 3.91 gears in it. I'd go with 3.55's if I was driving it on the street. I was told by the restorer that the car ran great. Both the Isky T-3 and Schneider 256F cams look like good choices. Use the 920 heads if they are on the engine. That's what came on the D/Darts.

As far as the rear end goes, pitch the 7 1/4 and get an 8 3/4. Back in Aug of 1965 NHRA issued a bulletin allowing the use of the B-Body 8 3/4 with 4.86 gears in the 273 CI, 235 HP A-Bodies. Racers must have been busting them regularly.

My one D/Dart ran a best of 12.92 at Detroit Dragway and 105 at Detroit, Milan and National Trail Raceway. This was in 1966 and in D/Stock with 7" slicks and 5.30 gears. I have 4.10's in my other D/Dart (380 HP - 360 Magnum Crate engine) and hate it on the street. It's got pep but I'm always looking for another gear to grab.

Good luck on your build.
 
I had a 3.55 7.25 SG survive 6 months behind a 68 spec 340 with 10" wide tires and a 727 in a lightweight 65 A. The only way I killed it was doing a neutral drop rolling backwards out of a driveway. I think it would still be working if I didn't pull that bonehead move. That '65 was pretty quick. I regularly toyed with a neighbors stock looking 340 Duster and always took it off the line.
 
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