Interesting stock 340 article.

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Following that on FB. Good article, even though it is info already known.
 
Well I don't know why guys on here are even building engines....just bolt on some headers and a six pack and you can have the same power as most of the small block built by the good engine shops that post here....
 
I did a fairly stock bolt on 340 about 20 years ago.....to get to 345hp it needed a 480 lift cam, intake, 750 DP carb, Headers, recurved dist, on a fresh 30 over 10:5 bottom end and rebuilt 2.02 X heads . I wish I would have done some pull stock but I personal doubt it would have gone over 300hp without the mods.
 
It was rated 275 for a p.m., however, when you did the Dino pull past that advertised horsepower rating, the engine made 325+ horsepower. Dead stock.
 
thesiren74 said:
Now do shoddy factory machine work and see how much h.p.
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100% right. The "increase" is not from anything more than much better machining and higher quality replacement parts. The right wall finish, modern fast seating rings, torque plate honing, align honing, square decking (that Rottler makes it easy), and MUCH better cylinder head machining on the valve job, back cut polished performance valves, better valve springs with less valvetrain weight, better rocker arms... Where did they think the power level was going to go?
Have a sop with 70s vintage equipment machine it to restore factory specs on the valve job and bore/hone, then use all stock parts, then assemble it like it's a Friday at 4:30, and see what it makes. This is why I haven't read magazines since my 20s.
 
moper said:
100% right. The "increase" is not from anything more than much better machining and higher quality replacement parts. The right wall finish, modern fast seating rings, torque plate honing, align honing, square decking (that Rottler makes it easy), and MUCH better cylinder head machining on the valve job, back cut polished performance valves, better valve springs with less valvetrain weight, better rocker arms... Where did they think the power level was going to go?
Have a sop with 70s vintage equipment machine it to restore factory specs on the valve job and bore/hone, then use all stock parts, then assemble it like it's a Friday at 4:30, and see what it makes. This is why I haven't read magazines since my 20s.
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the rings and bore finish is worth about 20 to 30 hp, alone. also, from the factory they came with a single angle valve seat.
3 angle seats are worth about 20 hp or so. no blueprinting what so ever.
 
Please show a test of a factory 340 Duster running 102mph or better in any standing 1/4 mile test back in the day. 325hp at the crank in a 3300 pound car should get you very close to 102mph. Don't think I've ever seen anything over about 99ish in any test. Most of those cars were tweaked, ultra tuned for the time, to make that happen.

This engine build also used a rocker that is closer to a true 1.5, maybe even slightly higher, not the 1.41-1.43 ratio that the stock stamped pieces were usually slinging valves.
 
I don't agree or disagree cracked back, but tire technology was nonexistent 45 to 50 years ago.
 
Cracked, I have seen such quick factory cars run that BUT they had been showered with the super golden magic wrenchs of the best in the day tweaking the factory settings & parts.

OOTB the cars would not ever do that. For dang sure.
 
What did NHRA factor the 340's power at. It was more that 300hp. 360 was higher too
 
If I'm around in another 30 years stock 340's should be making about 550hp on the dyno...getting better every year
 
My street strip numbers matching '71 340 Cuda, 727, 3550lbs+, stock motor, plus, .484 purple hyd., 750DP, dual plane intake, small tube hdrs, B&M S/holeshot 3500 verter, 3.55 grs, 8x26" M&H's, stock suspension, [email protected] = 300 track fwhp at SPR, 0 sea in 1982.
 
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perfacar said:
no blueprinting what so ever.
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That Rottler basically blueprints as it does it's work. If they honed the mains and then stuck it in that machining center, the fixture to hold it for the block operations mandated it being square decked and cylinder bores corrected in terms of perpendicular to the crank and placement. They may not have set the deck height, but that block was blueprinted.
 
rumblefish360 said:
Cracked, I have seen such quick factory cars run that BUT they had been showered with the super golden magic wrenchs of the best in the day tweaking the factory settings & parts.

OOTB the cars would not ever do that. For dang sure.
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article from 1984, hot rod, 340 duster= 14.7@ 94, aar cuda=14.5@99,340 cuda =14.9@ 95. which is about right.
 
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