1970 Challenger TA 340, 290 hp: 14.3 @ 99 mph
1970 Challenger 440, 390 hp: 13.62 @ 104 mph
1970 Challenger Hemi 426, 425 hp: 13.1 @ 107 mph

This is fun! Keep the myths flying!!!

 

go ahead keep posting stock times, i honestly dont care. no one is gonna race a car like that with street tires and stock manifolds. guess what engine is gonna benefit more from headers because it sure isnt the big block... The small engines revving to 7k need them more. If the stock manifolds and street tires choked a 12 second car down to the 14s, obviously there was some easy tweaking in need. 290 hp is the old rating system FYI, it was INDEED underrated in that day. they werent torque monsters, so yes they had horsepower to compensate.

but go ahead, keep calling it a myth. Ive seen the car in person, RIDDEN IN IT, street raced it with my 13 second car, and seen the videos of it running on a certified track back in the day. I believe all that before anything on a website. I never said they would regularly beat big blocks, but mild tuning for mild tuning they were right in the same ballpark.

 

Let him build what he wants and make a fool out of himself.

 

What!? That's a pretty ridiculous statement.

It ran the same as all the other cars rated at 290 hp, and slower than all the cars rated higher. Still not seeing where it was underrated.

I guess if you call -1 or 2 seconds "in the same ballpark", then you're right. I remember reading an article about the 427 ZL1 Camaro. The thing only pulled about 110 in the quarter stock, but air filter removal, carb jetting, open headers, gears, and tires, it was going over 120 mph. Guess those big blocks didn't benefit from mild tuning, huh?

Give it up, the big blocks were faster, just as they shoulda' been. The big blocks were bigger, had the same compression ratio's, similar lumpy solid cams, better heads, and bigger carb's.

Mike

 

I love these arguments. As soon as this type of banter dies, so will hot rodding.

 

I think it's a cool idea for a different motor.

Theres a easier (cheaper) way to get around the pcm rpm limit. Why not carb it? Get yourself a Victor Jr., have someone drill it for the LT1 bolt pattern, slap a Demon carb on it and a smaller HEI distributor, and rev away. My buddy made a jig for doing this exact thing to 4bbl manifolds. It takes him roughly 15 minutes to do it now. Another benefit of a carb setup is that it opens a whole new world for nitrous. You can select from tons of different plate systems that will all bolt right up. You'll need to run a cowl induction hood though. PM me for my friends email if you'd like some info on the intake conversion.

 

I loved the old Mopars. The 440 6-Pak Roadrunner I had was fast as hell, but just try to stop the thing or go around a corner and you sobered up real quick. The E-bodys were somewhat better in that regard. I don't think going fast was their problem, once you got rid of the skinnys and pea shooters.

And it was fun watching gasoline spill out the back when you nailed it.

 

you shifted the average big block no higher than 5500. a hot 340 or 302 shifted above 7000. headers offer the most benefit in high rpm conditions, thats ... pretty basic knowledge, so how is it rediculous? i never said a big block didnt benefit from headers, i just said they dont benefit as much.

they were underrated the same way todays LS1 was underrated. every last one of em dynoed higher than it should have out of the box. an episode of american muscle car would probably touch on that tid bit.

I was comparing 302 to 396 and 340 to 440, because thats what the common big blocks were in pony cars. obviously if you compare them to 427s and 426s its a different situation, because those are the hot big blocks, just like the 302 and 340 are hot small blocks. So no, im talking within .5 seconds of the most common big blocks.

i gave that up a long time ago. I only said they were close. obviously if you have the same setup with bigger cubes ... its gonna win. It is easier to make more power with more cubes, and probably cheaper too. Things have to be perfect with a small cube setup for them to scream, but thats how the 302s and 340s were. Im just tired of people posting factory performance numbers for Z28s and AARs. When their engines were designed to rev to 7k or more, theres a VERY GOOD REASON many of them came with headers in the trunk straight from the dealership!! If you really wanna talk stock for stock though (i dont)... cross ram 302s were about neck and neck with 375/396SSs, and capable of beating them.

 

best quote of the day!

 

So, let me get this straight. . . you want to compare high-performance, high-compression, solid cam'ed small blocks to low-performance, low-compression, hydraulic cam'ed big blocks? In that case, then I guess I agree that they were in the same ball park.

However, if you take a look at the ZL1 427, the motor was rated at 425 hp, but only made 375 hp in stock form. However, with open headers and a re-jetted carb, they would make over 520 hp, so they do, in fact, benefit tremendously from headers.

BINGO!!! That's been my whole point from the beginning of this thread!

 

mike mike mike, I was discussing something that would keep the lt1 heads and intake. lt1 heads on a big block arent going to make any power at all, they don't fit. when you're playing in the range of displacements that are achievable from a 350 block you're not going to see a lot of horsepower difference between a 330 and a 396, in fact Loyd Elliot said about his 383 that he was building that it would likely have less horsepower than if he built it as a 355. Big blocks make more power because in addition to big cylinders, they have nice big ports to feed those nice big cylinders. a 330 lt1 would easily make the same horsepower as a 383 lt1, just at a slightly higher rpm and with less low-end torque. However the setup I'm talking about will be A) easier to build, less clearancing issues, dont need a small lobe cam, dont have to get special rods, dont have to have the block clearanced and worry about going into a water jacket to accomidate extra stroke, yes a 355 would be a better build than a 330, becaus ea 355 would have the same advantages and 25 extra cubes, but 25 cubes is only 409 ccs, something im willing to give up for a unique engine. comparing a big block to a small block is pointless, big block heads in stock form flow more, they have to to feed the big displacement, they also make the car nose heavy and require more balast in the back and down low to compensate. btw you're not schlatre are you?

 

I like the lt1 intake, I was even thinking of putting a converted one on a vortec 383 I'm planning on building for my mercedes. I was going to go with an aftermarket pcm and preferably something similar to the mega squirt that I can adjust the code for (if i can find one that has the features i want which last i checked the mega squirt certainly did not), or hell if I get bored reverse engineer the stock pcm and write my own code for it (fat chance of that happening). and on another point I really like one point of the design of the optispark, inlike a traditional distributor the opti is on the front of the cam instead of the back of the cam, it puts less weight on the back of the cam (although the oil pump is still there) and thus less stress, and it is also less susceptible to flex of the camshaft (which theoretically I might see if I am turning the engine high enough although in reality I wouldnt expect more than 1 degree of flex to show up on the distributor)

 

LiENUS, I wasn't suggesting that you pull the LT1 in favor of a big block - just that you should take advantage of the cid and power potential in the LT1. Building a smaller motor is not the direction you want to go.

Absolutely incorrect. Once again, go take a look at actual dyno results. I've been involved in alot of dyno testing. A very well built 350 will make 450 rwhp. A well built 396 SBC will make 480 - 500 rwhp. A well built 440 SBC will make 520 - 550 rwhp.

It really isn't as difficult as you think. I've done it a few times.

If your goals are to build a "unique engine", then build whatever you want, but don't expect it to out-perform larger engines simply because it can rev higher. If you want something unique, but are worried about performance, then there are a multitude of options that won't actually slow down your car. How 'bout a 3 9/16" stroke, 4.030" bore 363? Or maybe a 3 5/8" stroke 370 cid? You could to a 4.040" x 3.48" 357 if you like the name. You could even build a 373 using the stock crank and block if you go .060" over and offset grind the crank to a small-journal. You would probably have the largest displacement LT1 with stock parts!

Like I said, I've run the gammut of SBC displacements. I've had 305, 350, 355, 360, 363, 383, and 388 cid. My favorites are the 383 and 388.

Nope. Shouldn't be hard to figure out who I am, though, because there is only 1 (maybe 2 now) turbo LT1's around BR.

Mike

 

I know the car you are talking about it; Scott Settlemire was driving it at the F-Body Gathering a few years ago (back when it was off Peachtree Industrial...'01 maybe?), and took me for a ride in it. I remember him saying something to the effect that it made no power below 3000, but I'd have to take his word for it...it wasn't under 3000 enough to tell!!! It felt pretty strong otherwise.

 

ok forget my post, I see like 3 people have already beaten the myths to death lmao.
engineermike - nice post finally some real numbers.