Horsepower help

AZ-360-Duster · 05-11-2007, 11:24 PM

I am new to the site and could use some help. My brother and I have argued for years (MOPAR vs. Chevy). To make this shorter we race in July and I don’t have a clue to how many horses are under my hood. If someone could give me a clue and advice to increase my HP I will represent MOPAR race day! I have a 1974 Duster, 360 bored 30 over, 340 heads, M-1 intake, Proform 750 carburetor, headman headers, 292 cam, 10:1 compression with new pistons and rings, 904 transmission, 2500 Hughes stall, shift/rebuild kit with Kevlar band, Ford 9”, 3” exhaust. It’s been more than 20 years since I’ve built a Duster, so I’m out of date with the tricks to make the Ponies. Advice, help or suggestions welcome.

Thanks,
John

moparmuscle0920 · 08-03-2007, 10:10 AM

hey this doesnt help you but when you rebuilt your duster where did you get your parts from do you have a good internet site for them or something?

ucfierocharger · 08-03-2007, 07:30 PM

Well, again I cant really help you with the hp question, my guess would be around 300, but really the only way to tell is dyno. Im curious though why you only have a 904 and not a 727. I would be kinda hesitant about drag racing in a 904 myself, but I don't drag cause I can't afford to fix it, so I wouldn't know.

TO answer your question moparmuscle0920, there is a summit racing store in ohio that is probably one of the best places to buy performance parts. they have a website as well, but its nothing compared to going to their store. www.summitracing.com

AZ-360-Duster · 08-03-2007, 09:13 PM

Summit and Jegs have a ton of items to help.

The reason I went with the A904 is 200lbs, the 727 is 200lbs heavier. The A904 is a solid trans up to the 500hp mark, once I reach 500hp, then I'll need to change trans. Check out Mopartech.net if you want to build a dream car.

ucfierocharger · 08-03-2007, 11:04 PM

I dont know if that weight stats are right. I can lift a 727 by myself, and I am not a big guy. If the 904 is that much lighter than it would only weigh like 20 lbs. TCI lists the shipping weight of their streetfighter tranny at 140lbs and the 904 at 112lbs

73DartSport · 11-13-2007, 04:55 PM

200lbs??? I don't know any mopar tranny that weighs that. Might check your specs on that one. 904's are decent transmissions, but for more power to the wheels the 727 would be a better choice. Also just like bigger cid motors the 727 will take over better in the upper ranges than the 904. Either way is a good choice and the 904 may be lighter, but not 200lbs.

CAT-TECH · 01-28-2008, 10:17 PM

At least 300 hp, id say around 350hp at the rear wheels. Download desktop dyno, its actually within 7% of your actual HP and torque numbers

440roadrunner · 01-29-2008, 09:53 AM

That's right, '73. I'm not an "automatic man", but back in the day, I could CERTAINLY pick up either transmission from the floor. Neither weighs 200 lbs.

The thing is--you're thinking like a Shivvy racer. lightweight. What good does lightweight do if it BREAKS?

Breakage is one of the things that led me to Mopar. The guy who was the original owner of my '70 sixpack had a '65 Chevelle when I met him. He had swapped in a '67
Camaro 350/muncie out of a wreck--this was the fall of '68. We "tuned" it, and later, the cam went flat. We shoved a 350hp cam in the thing, and he broke:

The 'ittle 10" rear TWICE

Snapped the main drive gear right off the Muncie

Two clutches

One clutch failed after a little "workout" up in Klamath Falls, OR. We had to drive all the way back to 'Frisco, shifting without the clutch. No fun, that trip back.

05-11-2007, 11:24 PM	#1 (permalink)
AZ-360-Duster Junior Member Join Date: May 2007 Posts: 2	Horsepower help I am new to the site and could use some help. My brother and I have argued for years (MOPAR vs. Chevy). To make this shorter we race in July and I don’t have a clue to how many horses are under my hood. If someone could give me a clue and advice to increase my HP I will represent MOPAR race day! I have a 1974 Duster, 360 bored 30 over, 340 heads, M-1 intake, Proform 750 carburetor, headman headers, 292 cam, 10:1 compression with new pistons and rings, 904 transmission, 2500 Hughes stall, shift/rebuild kit with Kevlar band, Ford 9”, 3” exhaust. It’s been more than 20 years since I’ve built a Duster, so I’m out of date with the tricks to make the Ponies. Advice, help or suggestions welcome. Thanks, John

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08-03-2007, 10:10 AM	#2 (permalink)
moparmuscle0920 Junior Member Join Date: Aug 2007 Location: OHIO Posts: 2	hey this doesnt help you but when you rebuilt your duster where did you get your parts from do you have a good internet site for them or something?

08-03-2007, 07:30 PM	#3 (permalink)
ucfierocharger USB car drive man Join Date: Jun 2007 Location: Cincinnati OH Posts: 142	Well, again I cant really help you with the hp question, my guess would be around 300, but really the only way to tell is dyno. Im curious though why you only have a 904 and not a 727. I would be kinda hesitant about drag racing in a 904 myself, but I don't drag cause I can't afford to fix it, so I wouldn't know. TO answer your question moparmuscle0920, there is a summit racing store in ohio that is probably one of the best places to buy performance parts. they have a website as well, but its nothing compared to going to their store. www.summitracing.com

08-03-2007, 09:13 PM	#4 (permalink)
AZ-360-Duster Junior Member Join Date: May 2007 Posts: 2	Summit and Jegs have a ton of items to help. The reason I went with the A904 is 200lbs, the 727 is 200lbs heavier. The A904 is a solid trans up to the 500hp mark, once I reach 500hp, then I'll need to change trans. Check out Mopartech.net if you want to build a dream car.

08-03-2007, 11:04 PM	#5 (permalink)
ucfierocharger USB car drive man Join Date: Jun 2007 Location: Cincinnati OH Posts: 142	I dont know if that weight stats are right. I can lift a 727 by myself, and I am not a big guy. If the 904 is that much lighter than it would only weigh like 20 lbs. TCI lists the shipping weight of their streetfighter tranny at 140lbs and the 904 at 112lbs

11-13-2007, 04:55 PM	#6 (permalink)
73DartSport Junior Member Join Date: Nov 2007 Location: Oklahoma Posts: 10	200lbs??? I don't know any mopar tranny that weighs that. Might check your specs on that one. 904's are decent transmissions, but for more power to the wheels the 727 would be a better choice. Also just like bigger cid motors the 727 will take over better in the upper ranges than the 904. Either way is a good choice and the 904 may be lighter, but not 200lbs.

01-28-2008, 10:17 PM	#7 (permalink)
CAT-TECH Member Join Date: Jan 2008 Location: Cali Posts: 42	At least 300 hp, id say around 350hp at the rear wheels. Download desktop dyno, its actually within 7% of your actual HP and torque numbers

01-29-2008, 09:53 AM	#8 (permalink)
440roadrunner Senior Member Join Date: Nov 2007 Posts: 272	That's right, '73. I'm not an "automatic man", but back in the day, I could CERTAINLY pick up either transmission from the floor. Neither weighs 200 lbs. The thing is--you're thinking like a Shivvy racer. lightweight. What good does lightweight do if it BREAKS? Breakage is one of the things that led me to Mopar. The guy who was the original owner of my '70 sixpack had a '65 Chevelle when I met him. He had swapped in a '67 Camaro 350/muncie out of a wreck--this was the fall of '68. We "tuned" it, and later, the cam went flat. We shoved a 350hp cam in the thing, and he broke: The 'ittle 10" rear TWICE Snapped the main drive gear right off the Muncie Two clutches One clutch failed after a little "workout" up in Klamath Falls, OR. We had to drive all the way back to 'Frisco, shifting without the clutch. No fun, that trip back.