Weight of 7 1/4 vs 8 1/4 vs 8 3/4 vs Dana 60?

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Jeff 63ValiantConvertible said:
I'm trying find some information for building a 225 on a budget build...trying to find some power out of the 6.
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Not much you can do naturally aspirated to get more than about one HP per cubic inch, and that will be a somewhat rowdy street engine. It all depends on how much lope you can stand and whether or not you need vacuum to run accessories like power brakes. Head milling (about .100") is the first place to start, then more camshaft, bigger valves and port work If you want to go that far. It all depends on "how much" power you're looking for.
 
RustyRatRod said:
Not much you can do naturally aspirated to get more than about one HP per cubic inch, and that will be a somewhat rowdy street engine. It all depends on how much lope you can stand and whether or not you need vacuum to run accessories like power brakes. Head milling (about .100") is the first place to start, then more camshaft, bigger valves and port work If you want to go that far. It all depends on "how much" power you're looking for.
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Wow...thanks for the response. I didn't know if there could be something less intrusive such as adding an intake and larger carb, perhaps headers...I'll probably have to wait to do what you suggested ($), but I am glad that I asked. Thanks for the information.
 
I shipped a A body 8 3/4 to Ca. Seems like I remember 160 lbs with drums complete. It was 200 on the pallet.
 
Jeff 63ValiantConvertible said:
Wow...thanks for the response. I didn't know if there could be something less intrusive such as adding an intake and larger carb, perhaps headers...I'll probably have to wait to do what you suggested ($), but I am glad that I asked. Thanks for the information.
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I would "GUESS" with no other mods, adding a small four barrel on top of say the Offy intake and some Clifford headers would probably get you from the factory 14HP rating to about 175. MAYBE. Certainly by including the head milling on top of all that. The problem is, the 225 never got its own cylinder head. It has to breath through a head designed solely for the 170. Chrysler never redesigned the head for the 225, so that's "all we got" unless you install bigger valves and or port. They respond very well to forced induction, but then, cylinder head mods are nowhere near as important, as you're pushing the mixture through the engine, instead of relying on a low pressure era at the mouth of a carburetor. That is a much different story than forced induction and needs "all the help" it can get.

What I would recommend would be this, if you don't want MAJOR mods. Find a factory super six (two barrel) intake and carburetor. I would use a Carter BBD off a 318. MUCH less expensive and MUCH easier to find. Like an early 70s version. hog out the outlet to a stock manifold like I had my friend Freddie do here: Exhaust Manifold Mod

BUT the important thing here is USE a 2.2 or 2.5" pipe, NOT the stock 1.75 pipe, or all that work in the manifold is for naught. And use the bigger exhaust ALL the way back with a good, free flowing muffler. You'll also want to give the distributor a good performance advance curve. Those mods all together will make a nice increase in power AND mileage. Then you can decide later if you want to do head milling, bigger valves, porting more camshaft and such.
 
You can generalize the weight of the various rearends, but "what does x rearend weigh" cant be answered. It depends entirely on equipment and width and application.
A full width c-body 8 3/4 with 11"drums will weigh more than a passenger dana (as opposed to a truck dana) with discs and a spool at a-body width. Even a narrowed truck dana with thick axle tubes and 35 spline axles and 11x2 brakes and a clutch suregrip will be a bunch heavier than an a-body 8 3/4 peg legger with 10x1 3/4 brakes.
The above mentioned test where the nine inch ford was heavier than the dana was entirely due to the very heavy ford brakes. Without the brakes, the dana was about 25 lbs heavier (i dont
remember exactly, been a long time since i saw that test.)
Of the generally used performance rearends (my personal opinion ONLY!) the 12 bolt, 8.8 ford, 8 3/4, and 9" all weigh pretty much the same, if equipped similarly, and a dana 25-50 lbs more, depending on equipment.
I think the 8 1/4 is lighter, and the 7 1/4 dont weigh much at all.
 
RustyRatRod said:
I would "GUESS" with no other mods, adding a small four barrel on top of say the Offy intake and some Clifford headers would probably get you from the factory 14HP rating to about 175. MAYBE. Certainly by including the head milling on top of all that. The problem is, the 225 never got its own cylinder head. It has to breath through a head designed solely for the 170. Chrysler never redesigned the head for the 225, so that's "all we got" unless you install bigger valves and or port. They respond very well to forced induction, but then, cylinder head mods are nowhere near as important, as you're pushing the mixture through the engine, instead of relying on a low pressure era at the mouth of a carburetor. That is a much different story than forced induction and needs "all the help" it can get.

What I would recommend would be this, if you don't want MAJOR mods. Find a factory super six (two barrel) intake and carburetor. I would use a Carter BBD off a 318. MUCH less expensive and MUCH easier to find. Like an early 70s version. hog out the outlet to a stock manifold like I had my friend Freddie do here: Exhaust Manifold Mod

BUT the important thing here is USE a 2.2 or 2.5" pipe, NOT the stock 1.75 pipe, or all that work in the manifold is for naught. And use the bigger exhaust ALL the way back with a good, free flowing muffler. You'll also want to give the distributor a good performance advance curve. Those mods all together will make a nice increase in power AND mileage. Then you can decide later if you want to do head milling, bigger valves, porting more camshaft and such.
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Thank You, Rusty. I certainly can appreciate your knowledge. If you don't mind could I message you on how I am coming along and get further advice. I think I have a good starting point now. I had my original 120 spin a bearing and I haven't been able to find a bottom end rebuild kit. I'm ok with that because the 170 wouldn't pull the hat off your head. I just bought a Super Six Engine 225 out of a 1974 Duster, so this gives me some hope that I can put some additional power behind the Slant 6.
 
Jeff 63ValiantConvertible said:
Thank You, Rusty. I certainly can appreciate your knowledge. If you don't mind could I message you on how I am coming along and get further advice. I think I have a good starting point now. I had my original 120 spin a bearing and I haven't been able to find a bottom end rebuild kit. I'm ok with that because the 170 wouldn't pull the hat off your head. I just bought a Super Six Engine 225 out of a 1974 Duster, so this gives me some hope that I can put some additional power behind the Slant 6.
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The Super Six was not an option until a good bit later, so be careful what you have there. And sure, message away.
 
Awww, man...I haven't picked it up yet. It was in a1974 Plymouth Duster.
I appreciate the warning...Going to have to stop payment on it.
Thanks for letting me know/
 
Jeff 63ValiantConvertible said:
Awww, man...I haven't picked it up yet. It was in a1974 Plymouth Duster.
I appreciate the warning...Going to have to stop payment on it.
Thanks for letting me know/
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now it might have the Super Six stuff on it, but it didn't come that way. Not that early.
 
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This is the engine...Is it or not a Super Six 225...it is in a 1974 Plymouth Duster.

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famous bob said:
been told by a well known superstock racer that there is 35lbs. diff. between the dana 60 and an 8 3/4; like me, he started blowing 8 3/4`s and had to go to a dana to stop it. -------------------bob
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"I bet" it is more than that..........what with guys "making" them by narrowing truck '60s
 
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