Since I know very little about big blocks, I hope this doesn't sound goofy, but what are typical engine speeds for peak torque, peak horsepower, and redline for, say a 396 engine? Not a L78, just a...er,garden variety low-tune 396 if there is such a engine.
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Re: BBC Peak Torque & Horsepower RPM
IIRC the "entry level" 396 that was used in '65 A (SS396) and B-bodies was rated at 325 HP. I don't recall the peak torque rating, but it would have been around 425 lb-ft. These ratings were similar to the other similarly configured division engines of similar displacement like the Pontiac 389 used in the GTO that was rated at 335 HP.
Peak torque and power speeds would be in the same range as medium performance 327s - about 3000 for torque and no more than about 5000 for power with a redline of no more than 5500.
The base SS396 engine was not at all impressive. One buddy of mine back then had a base 335 HP GTO, and he could regularly trounce base engine SS396 Chevelles. He shifted the Goat at 5000.
Duke -
Re: BBC Peak Torque & Horsepower RPM
Thanks, Duke...Just what I needed. I figured YOU would be able pull something off the top of your brain if you were around.
My bud has just bought himself a 69 SS Camaro project car; pretty nice old car for having been raced and put up wet. It has some suspicous looking areas, but it far exceeds most of the other rust buckets out there.
He has a 396 big block to use in the car...I haven't checked the machine stamp, but it's probably exactly what you said, entry level big block for A/B bodies. He's thinking an aftermarket TPI system and a Tremec six speed conversion kit...otherwise, it'll be dead stock unless he goes for bigger wheels and tires. I'm trying to help him with enough info to pick the best tranny and axle ratios.
I don't know what ratios are available in the aftermarket Tremecs, but the C6 MZ6 (Z51) tranny ratios (2.97, 2.07, 1.43, 1.00, 0.71, 0.57) seem to work well with the 3.42 axle, however...the LS2 has a 6500 redline.
Got any old hot rodder thoughts on optimum street gear ratios for this set-up? Email me if you prefer.Comment
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Uh-Oh...Back My Truck Up Here...
I talked to him, I was all wrong on the engine: It's probably a mutt truck engine...apparently a 454 stamped T0417I(?)RB with 3989289 block casting number.Comment
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Re: BBC Peak Torque & Horsepower RPM
An aftermarket fuel system and transmission is going to set your buddy back several thousand dollars, and considering what can be gained, I don't think he's getting a very good return, especially if the car is still fairly original.
As with ANY production engine, the best single improvement you can make is to pocket port/port match the heads/manifolds with multiangle valve seats. As with any other production engine this will increase peak power and useable revs by 8-15 percent without affecting idle quality or low end torque. This yields a considerably more flexible engine without any tradeoffs, and a 2.5" exhaust system with low restriction mufflers is also a very cost effective modification. Many bolt-on low restriction exhaust system kits are now available for vintage muscle/pony cars.
Those vintage muscle/pony cars typically had a wide ratio Muncie with about a 3.3 axle, which was a good all around combintion - enough grunt to light the tires without excessive revs at freeway cruising speed.
Refreshing the OE engine/drivetrain components and a good exhaust system will likely cost less than some aftermarket fuel system and a modern six-speed manual transmission, and it will have better performance by putting the money into the most cost effective improvements.
DukeComment
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Re: BBC Peak Torque & Horsepower RPM
The car has been raced regularly, and currently has a built small block/THM the owner wants to keep. The original small block engine is long since gone, but the car is fairly original otherwise. He's buying the car sans engine/tranny. He also has a Muncie four speed he could use, but wants to make the car something special.
I'll pass your comments on...Thanks.Comment
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Re: BBC Peak Torque & Horsepower RPM
Keep in mind that there are two versions of the "small" 396, the 325 hp and the 350 hp, the only difference being the 350 hp version shared the camshaft from the 390 ho 427 engines. There is a major difference in the performance of the two engines with only the camshaft change. The later Truck heads were absolute junk for any performance work, much better to use the passenger oval ports from the late 60's early 70's, and they are realitively plentiful. Same thought process for the 454.Bill Clupper #618Comment
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Re: BBC Peak Torque & Horsepower RPM
Thanks for the comments, Bill...Sounds like it would be nuts NOT to change the camshaft. I'm going down to his place tomorrow...mebbe we can pull off the valve covers and read the head casting numbers; perhaps I can get someone to then tell me what the heads are.Comment
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Pickup truck engine is the BEST!!!
If it's a stock 1973 to 1978 light truck engine, it will have the 049 or 781 casting heads. They are considered the BEST BB oval port heads! Rebuild the short block with the small dome type pistons to achieve a static compression ratio of 9:1 to 10:1, pocket port the heads, and stick with a SHORT duration hydraulic cam with about 114 lobe centers and you'll have a stock sounding engine that will pull harder than a lot of the "High Perf" engines. If your crank needs a regrind, buy a cast 4.25 stroker crank from Scat or Eagle for $220 - $300 and use Keith Black hypereutectic pistons.
Unless you are running open headers, you will get more usable power from the above engine. Also remember that most street driving is from 1500 to 4000 RPM. Does it work? Sure does! I currently own about 20 BB engines and up to 5500 RPM, the 489 strokers with the short duration cams KICK BUTT!
Good luck,
MarkComment
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Anybody Know What The IRB Suffix Is? *NM*
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Re: Anybody Know What The IRB Suffix Is?
Can't find it in Hollanders up '65 thru '92.Bill Clupper #618Comment
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Maybe The Suffix Is Actually 1RB? A Boat Engine??
Ewwww...It just keeps getting worse. Looks like my bud has a BOAT ENGINE for his Camaro project.
The block casting number has to be 3999289 (misread as 3989289)...that's a 454 2-bolt main used from 72-78. I couldn't find that specific suffix, (1RB), but all the other suffixes starting with the numeral 1 are marine engines!!!
Clem, Tell me something about boat engines, man...In a Camaro, would it be (1) faster than a bottom-feeding Sting Ray, (2) A fish out of water, or (3) A Boat ANCHOR.Comment
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boat engines are built for torque because
all that water is a BIG DYNO. that is why most dynos are called "water brakes" nothing like a big torquer engine as i had a 482 cu in BBC in one of my pickups and we ate corvette for lunch. depends what season it was i kept a snowmobile or a couple of dirt bike in the bed for added traction.Comment
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It's At Least A Complete Engine...
The casting date on the block (D 11 73) matches the heads (C 28 73). The heads are casting number 353049. Mortec.com sez they're oval port, 122 cc, open combustion chamber...FWIWComment
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like I said above, 049 heads are GREAT! *NM*
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