383 STOCK B body vs 5.7 Challenger

[Sweet5ltr]

Do you have any data on this? It would be interesting to see. It makes sense that there is a lot of effort by the auto makers to eliminate theses losses as much as possible and probably have come a long way, but the flip side is 8 speed autos would have more parasitic losses over a three speed by their nature, I would guess.

Yes & no, as the 6.4/392 is rated at 485 (NET) HP and the M6 Challengers regularly dyno around 430 RWHP. That’s around 12% drivetrain loss.

Most don’t consider NET HP rating differences when talking about 440’s, everyone says ‘375 - 390 HP’ but that’s not necessarily true, in reality, the only power that matters from an engine output term is NET (with all accessories attached and exhaust system). Now, compare the 485 HP 6.4/392 to the 1972 440 6-pack NET figures at 330 HP.
290 RWHP would be a similar drivetrain loss figure, and that is fairly accurate.

Now the difference is most likely with the 8HP70 transmission, as the drivetrain losses are minimal over the TR-6060, nearly identical along with having a much better gear ratio spread. TF-727 on the other hand, we know, has much more than 15% drivetrain loss, typically well over 20% and the gearing leaves a lot to be desired. People don’t really think about the big picture, the reason the GEN III Hemi cars run well is the Eagle & Apache heads with modern intake / cam profiles. Throw a great set of heads (TF 240) on a B/RB with the basic upgrades and not worry about a modern SRT. Engines are just air pumps, modern GEN III Hemi heads flow over 300 cfm, B/RB heads are lucky to flow 215 cfm.

 

[biomedtechguy]

Throw a great set of heads (TF 240) on a B/RB

On my "to do" list...I've got stock 452 heads right now, not doing any justice to the 292°/.509 cam that was in it when I got the car. (I love the way it sounds! Pulls hard too, all the way to 6k)

 

[cdr]

Yes & no, as the 6.4/392 is rated at 485 (NET) HP and the M6 Challengers regularly dyno around 430 RWHP. That’s around 12% drivetrain loss.

Most don’t consider NET HP rating differences when talking about 440’s, everyone says ‘375 - 390 HP’ but that’s not necessarily true, in reality, the only power that matters from an engine output term is NET (with all accessories attached and exhaust system). Now, compare the 485 HP 6.4/392 to the 1972 440 6-pack NET figures at 330 HP.
290 RWHP would be a similar drivetrain loss figure, and that is fairly accurate.

Now the difference is most likely with the 8HP70 transmission, as the drivetrain losses are minimal over the TR-6060, nearly identical along with having a much better gear ratio spread. TF-727 on the other hand, we know, has much more than 15% drivetrain loss, typically well over 20% and the gearing leaves a lot to be desired. People don’t really think about the big picture, the reason the GEN III Hemi cars run well is the Eagle & Apache heads with modern intake / cam profiles. Throw a great set of heads (TF 240) on a B/RB with the basic upgrades and not worry about a modern SRT. Engines are just air pumps, modern GEN III Hemi heads flow over 300 cfm, B/RB heads are lucky to flow 215 cfm.

12% loss on a Dyno Jet yes, but not on other Chassis dynos, Mustang & others are 17ish %. look at what the difference of Hellcats are, 707 hp, 675 rwhp Dyno Jet, 630 rwhp on a Mustang, if a TF727 consumed 20% power it would BURST into flames LOL, that heat has to go somewhere.

 

[BSB67]

Yes & no, as the 6.4/392 is rated at 485 (NET) HP and the M6 Challengers regularly dyno around 430 RWHP. That’s around 12% drivetrain loss.

Most don’t consider NET HP rating differences when talking about 440’s, everyone says ‘375 - 390 HP’ but that’s not necessarily true, in reality, the only power that matters from an engine output term is NET (with all accessories attached and exhaust system). Now, compare the 485 HP 6.4/392 to the 1972 440 6-pack NET figures at 330 HP.
290 RWHP would be a similar drivetrain loss figure, and that is fairly accurate.
.

I think you're saying you have no direct correlation. The 20% drive train loss commonly used in the aftermarket high performance community is always a comparison of gross HP run on a dyno using SAE J607 standard, verses the auto company's measuring net HP using SAE J1349.

I've run my motor on both an engine dyno and a Mustang chassis dyno. There was a 21% difference which would be considered drive train loss. Making some reasonable HP loss assumptions to go from gross to net (air cleaner, alternator, fan, exhaust) and converting SAE J607 to J1349, it comes out to 12 - 13% drive train loss.

Over simplification of the details results in a non apples to apples comparisons. And I'm not saying that there is not less drive train loss in late model cars, I'm saying that I have not seen anything that really makes the case with apples to apples data.

 

[dvw]

For what it's worth a 3.6 6 cylinder Challenger will run 14.5@96. This is at over 4000lbs to boot.
Doug

 

[horace]

Thanks for all the discussion, I was just curious how bad it would be 8 car lengths would be like the LITTLE BIG HORN all over again. I have had the Super Bee for soon 50 years so, I didn't want break anything besides I enjoy my clean drivers license compared to all the marks I used to have. It looks like no one has ever raced stock to stock
though. The Hemi Challenger is soooo much more car but 50 years gives time for lots of improvements. Thank you

 

[mmissile]

For what it's worth a 3.6 6 cylinder Challenger will run 14.5@96. This is at over 4000lbs to boot.
Doug

That's exactly the area where my fast and stock muscle-cars ran, back in the day. My Caravan puts a hurtin' on lots of stuff. It's too funny.

 

[mmissile]

Even with 315/35/17 Toyo Proxes TQ drag radials, I am having trouble with off the line traction. I'm working on various solutions, but the inability to launch any higher than 1k RPMs is hurting my 60ft times badly and my 1320 time as well.
Having said that, when I was running 13.8s at 104 I was neck and neck with a 2010 SRT Challenger.
Now the last time I ran I had not yet switched out the 3.54s and 4 speed for my current Passon a855 5 speed (which shifts great under power at the track) and 4.10 gears. The last "track day" before those changes I was running 13.3 at 106, I would have beat that Challenger every time, and I beat my friend's SRT Jeep 3 out of 3...

That's cool. You couldn't even hear the Jeep, though.

 

[66Satellite47]

Some of the new are surely very fast. New technology. My first day at the strip in 2013 with my 500" Satellite, lined up with new HP Corvette. Left & was way ahead, very close at the line. Time slip showed he was 8+ MPH faster. I knew I needed to put more power in my motor. New stuff can be really fast.

 

[Speedbird]

So, I'm commuting to work in my basically bone stock 318 "Duster" and people in new Carreras and Challengers and Chargers pull up beside me like they want to race.
What's up with that?
Fine.
First we drain the oil out of our engines.
Then I'll race anything.

 

[PRHeads]

I have a 2012 Mustang GT(gasp!!), 5.0, 6 speed manual, 3.31 gears.
I had it at the track once, and only got to make 3 passes.
The only thing not 100% as delivered from Ford was it had a couple oil changes.

Really hard to get it going off the line at the track without totally frying the tires.
There was zero hook with the OE tires at the track(hooks way better out on the street).
Still went a wheel hopping 13.42@110....... only used 4 gears.

The new stuff runs pretty good.

When I first had my satellite running in 82 with my freshly rebuilt 440......with a cam, intake, carb, 3.23’s, g50-15’s out back....... the best I ever got out of it was a 14.06........ and it never broke 100mph with that combo.

A few years later I was working on my friends 1969 GTX.
I re-ringed the original 69,000 mile 440, had a valve job done on the heads, did some mild bowl porting, and used the bigger summit cam(which was a GK cam back then), stock intake and carb, and he had found one of the factory fresh air set-ups for the car.
I put some 4.10’s in it, and he put some Coker red stripe G70-14’s on the original magnum 500 wheels.
It also got an 11” converter.
After a bunch of runs at the track to get the launch situation sorted out I got it to go 13.75.
I don’t recall the speed exactly, but I wanna say it was like 103-104.

Maybe 12-14 years ago I freshened some 906 heads that came off a very low mileage 383 in a 69RR.
Someone had bought this close to a survivor car and wanted to make sure it was totally road worthy.
I touched up the heads and rebuilt the carb.
The shop that was working on the car went through all the suspension, brakes, exhaust, etc.
It was a 383, 4speed, 3.23 combo and I got to drive it after they had it going.
A lot tighter than my 68 which had about 80,000 more miles on it.
But....... I gotta tell ya........ it didn’t feel very “muscular” for a muscle car to me.
That shop has a chassis dyno, and they had it dialed in okay.
I guess 335 1969 vintage hp isn’t as impressive after you’ve driven stuff with 200-300 more.

 

[BSB67]

Found the time slips.

Original 67 Charger. 440 -375 hp, auto, 3.23 gear. Original motor w/ +100,000 mile. I'm the second owner. Bought it from a retired female school teacher in Tennessee. I had a valve job done, and installed the MP 272/.455 cam. I did this work in a rented storage unit. Everything else was factory, including the single point dist.. Probably a Midas exhaust. I did remove some weight from the secondary butterfly counter weight from the original 4327 AFB carb.

March 15, 1987, Tri-State Dragway, Hamilton OH. 3 passes, 14.6 to 14.9, and 93 to 94 mph. I actually weighed the car that day w/o me - 4230 lbs. In my notes I have a calculated 296 hp average. I'm sure that back then I used the weight to power ratio and Ma Mopar's Dragstrip Dyno to get the hp.

Rebuilt the engine in 1990 with a slightly taller piston (68-69 piston), same cam and heads, but put on a 6 bbl. For the following 4 years ran pretty much 13.3 to 13.5 at 102 -103. Found one time slip with a 13.25 @ 104 .3

 

[cdr]

Found the time slips.

Original 67 Charger. 440 -375 hp, auto, 3.23 gear. Original motor w/ +100,000 mile. I'm the second owner. Bought it from a retired female school teacher in Tennessee. I had a valve job done, and installed the MP 272/.455 cam. I did this work in a rented storage unit. Everything else was factory, including the single point dist.. Probably a Midas exhaust. I did remove some weight from the secondary butterfly counter weight from the original 4327 AFB carb.

March 15, 1987, Tri-State Dragway, Hamilton OH. 3 passes, 14.6 to 14.9, and 93 to 94 mph. I actually weighed the car that day w/o me - 4230 lbs. In my notes I have a calculated 296 hp average. I'm sure that back then I used the weight to power ratio and Ma Mopar's Dragstrip Dyno to get the hp.

Rebuilt the engine in 1990 with a slightly taller piston (68-69 piston), same cam and heads, but put on a 6 bbl. For the following 4 years ran pretty much 13.3 to 13.5 at 102 -103. Found one time slip with a 13.25 @ 104 .3

WOW 4230 without driver DANG!!!!

 

[WileE]

All good reading here. But simple me looks at things simply. In my "modern" muscle car, I'm an old man yawning. In my RoadRunner, I'm a 17year old kid again smiling !!

 

[Cranky]

WOW 4230 without driver DANG!!!!

Hey Charlie, your car isn't exactly light lol. Let's stick your drive train in mine and see what it'll do! Wishful thinking on my end.....

 

[Sweet5ltr]

Good responses here, I'm just stating the obvious, where are the 485 HP NET (525 HP claimed) Mopars on the rollers making 400 - 440 to the tire? It's an impossible task to actually know because at these power levels, typically the entire drivetrain is modified.

Yes, we can assume near equal loss with modern torque converters / limited-slip units installed, but this isn't 'apples to apples' with a majority of classic car enthusiasts. As a broad statement, it's an assumption that newer cars will generally have less drive train loss or at least, they can compensate for variables in milliseconds and repeat results. I'm not a dyno operator, would love to hear some actual relative info on the subject!

For instance (just one example), period correct 1970 Challenger (426 Hemi) A-833. 314 RWHP on the rollers. Allpar has some great information regarding the true output of the Elephant, around 460 HP at the crank (which we can all agree is remotely close). Even considering a 20% drivetrain loss from GROSS figures, we're missing well over 50 RWHP with a manual transmission. Is the tune 'that far off', or is there really a massive loss with older cars (especially running through a D60 rear)?

Just to hit home here, pulled from a Hot Rod article. Chassis dyno results, and like any dyno, the numbers are only relative to this dyno.

Modern ---
2006 SRT8 (Vortech S/C) / A5 put down 535 to the tire.
Stock 2010 R/T / A5 put down 335 to the tire. 10% loss.
Stock 2015 Scat Pack / M6 put down 406 to the tire. 16% loss.
Stock 2015 Hellcat / M6 put down 642 to the tire. 10% loss.

Classic (lets all shed a tear for the 69' GTX) ---
1969 GTX 543ci. / Auto put down 285 to the tire. (440 source heads, 2" headers, roller cam, 850 carb, torker intake)
1969 Daytona 440ci. / Auto put down 302 to the tire. (SD intake, .500" camshaft, 750-carb, 2" headers)
1966 Coronet 440ci. / Auto put down 340 to the tire. (906 heads, M1 intake, 825 carb, 11.7:1 CR, 2 1/4" headers, hydraulic camshaft)
1970 Cuda 422ci / 4-speed put down 401 to the tire. (220cc heads, .585" camshaft, Victor manifold, 950 carb, 1 7/8" headers).
1977 Power Wagon 572ci. HEMI / Auto put down 450 to the tire. (1050 Dominator, dual-plane intake, 426 S/R heads, .620" camshaft)

What we do see with modern cars, is more repeatable results.

 

[Cojohnso1]

First off. Comparing a Supercharged motor to a N/A on HP graph is a bit misleading. The Hellcat is putting down it's torque advantage at nearly 1200 RPM higher than top BB. And to get to the higher range takes time. Precious 10th's of seconds. I have a 10 sec Duster with a 451 N/A to single 4 barrel. Yes car is lighter than Hellcat. And is geared for 1/4 effort. I have raced a couple Hellcats that I never saw once light went green. And I'm no where near the 770 horse that Hellcat's boast. (1/8th mile street race even worse for the newbies.) They're only chance is on the big end. What is also not considered is that yesterday's blocks are benefiting with today's component and tighter tolerance builds. Aftermarket heads that get the big boys finally breathing right. It's funny come Sunday? I never see the newer models in the bracket's finals. Seems to always be the same players. Muscle Car era builds. (Now I'm sure other tracks have different demographics. And of course there are pure stock classes that are nothing but new.) But King street and especially any Outlaw class? Kitty cats need to stay clear. My Duster is no match to some of the crazies out there. Just my observations. And yes, I am probably bias to the past.

 

[66Satellite47]

The main thing for me, new cars are really neat & powerfull. I would have no idea how to work on them. I spent a while looking at Hell Cat a few weeks ago. Power sure sounds amazing. I would need a young guy to keep it going.

 

[cdr]

With all this speculative HP robbing A518, 727, dana 60 stuff, my car must have 750 HP TO RUN what it does , guess what, it does not LOL

 

[Sweet5ltr]

With all this speculative HP robbing A518, 727, dana 60 stuff, my car must have 750 HP TO RUN what it does , guess what, it does not LOL

546 HP according to the Wallace racing calculator, which is really reasonable at 512ci. For example, the Charger Hellcat weighs around 4900 lbs with a 200 lb driver and fuel. That's why it takes 640 to the tire to put down a respectable ET (without an incredible 60' time).

To put it in simple terms, power to weight. That Hellcat has a power-to-weight ratio of 0.14 with 707-HP. Your car has a power-to-weight ratio of 0.13 (considering 4,200 lb with driver) with 546-HP. Hellcat runs only a few more MPH through the quarter, even though it makes another 150 HP at the crank. Your car probably loses a slight bit of MPH because I'm sure it has a decent 60' time.

Just imagine if you were at a-body weight. Would make a Hellcat look really silly.