I’m seeking some opinions on what y’all think a 1971 Roadrunner with these options would run in a quarter mile:

440 six pack
Bored 30 over
10.5 to 1 compression
Aluminum H Beam Rods
Forged Crank
Forged Pistons
Stock 906 heads with 3 angle valve job
Comp Cams Extreme Energy XE262H
Stock Holley Carbs with larger jets
Factory Electronic Ignition
Stock Manifolds
2.5” exhaust with Flowmaster 40 Series
TCI Streetfighter 727 with 2400 stall converter
8 3/4 with 4.10 rear gears
275/65/15 BF Goodrich Radial T/A’s on the back with Rallye Wheels

Car has power steering and power brakes and a Sanden A/C compressor. Car also has stock airgrabber hood with K&N air filter. Thanks ahead of time for your answers!

16.5 @ 75mph? Depends on who built and tuned it. Radial T/A s are spin city on a minivan. Post up some 12's and I will be impressed.

Eagle H-beam rods are 4340 chrome moly steel. i saw the posts on Questions and answers and you stated they are eagle rods. Tuned right it should run low 13s.

Hotrod mag could only get a 15.1 out of a new 71 auto 440-6 bee and you have a mild cam, a vj and a bit of a vert on them.

Your tires if the newer BFG suck and if they are older they are aged and either way a good 340 wouldnt hook well.

Id be shocked to see quicker then a 13.9 as it is, but good luck.

IIRC, Car Craft got one into the 12's with similarly equipped as yours. They were testing a 6 bbl RR against an LS-5 Chevelle. The RR was faster stock than tbe Chevelle was with headers and gears. They called the RR 'Superman's Supercar'.

Low 13s or high 12s w/ different tires that will hook and considering it's tuned well.

low 14 high 13 IMO

My 440+6pk motor made 415 track hp with a single 850DP, stock 906's and a big solid cam, hdrs. If yours is on a par with that corked up and with a good tune, with a weight of 3800 at the line it should run 108>109mph which is normally a lowish 12. However with those tyres you'll prob lose over 1 sec off the hit, I would say mid>high 13's. Some 29" tall slicks would be the way to go for a 5500 trap rpm inc. slip and 12.2's@110.

Ralph from Supercar has one he runs in Pure Stock with a 4 speed.
Best so far is 13.6@101.

I'll be interested to hear your impressions of that cam in the upper rpm's.

Hopefully you used quench dome pistons to get to that 10.5cr........ Otherwise I predict ping city with that short duration cam.

My shoot from the hip guesstimate, based on the small fast rate cam, non-sticky tires, and potential Texas heat and humidity......... Mid/high 14's @92-95(first couple times out with it).
With some tuning, practice, and better tires........... 13.7@99.

Thanks for all the responses! What is a good tire that will hook better and still be ok for the street? Also, do you guys see anything lacking that would be an easy way to step up he performance?

Better tires, higher stall converter, headers, ported heads or aluminum heads.

Your in the mud now, you got to run with the BFG-s first

Then switch to a decent 275/60 drag radial.

Since you have a auto and BFG drag radial would probably work well and act like a street tire, yes there are better hooking drag radials but I dont think youd need one thats more slick like then street like, if that makes any sense.

But yea, it would be nice to see ya try your current BFG tires just to see how well ya can do.

You have to start somewhere.

Might as well just try it like it is to see where you're at.
That will give you way more useful info that what any of us come up with before the car has been run.

With Radial T/A's our Challenger has run from 15.20 with my wife driving (she got better down to 14.20s). To my all time best of 13.20. With drag radials, 12.70's, with slicks and a 4.30 12.50. All with exact same tune.
Doug

I don't think you'll get out of the 14's as-is. Stock heads with stock valves with a valve job and a very small cam. Should make for a good street cruiser. With good tires and a well sorted suspension I would expect mid-low 13's.

Aluminum rods?

As is, I'd guess mid 14s.

15.20

'58 savoy, 3900lbs

'70 440 from a town and country wagon.
ball honed, new rings, bearings, and rod bolts.
stock pistons, rods, crank. ( crank need to be polished)
Lunati bracket master cam, with springs to match, ductile iron rockers.
stock heads, that were magnafluxed and just cleaned up, new seats, etc. no port work. sanderson block hugger headers, 3 inch exhaust with race magnums.
torker 2 intake, 850 double pumper.
3,000 stall, 4.56 gears.
12.24@ 111 on a set of L-60 McCrearys.

Car has never been to the track. Forgot to add that it has the Mopar Performance larger torsion bars and Super Stock Springs. Has a 3.23 gear in it now, was planning on swapping the 4.10 in soon. Would that make a difference in maybe helping with the wheel spin?

Just an opinion like many but if you have a good running car you can drive as it seems you can with the money youd throw at it to still be slow in the big picture even older new style challengers are cheap and the performance options are endless.

But to your current question, wow 3.23 and BFG tires are the perfect smokem combo, when they start to spin they just keep spinning unless you back all the way off.

Knowing now your running a 3.23 gear id say you might be in the high 14 low 15 area, but it sounds like a car you can enjoy alot by just driving it unlike many of us here.

I don’t know guys, this seems like a 440-6+ build. Yeah it’s a mild cam but still better than a stock cam by quite abit. Yeah it might run low 15’s but you’d have to do everything wrong. Potential to run well into the 12’s.

Back in 1975-6, I can't remember for sure but my 1969 440 six pack with SS spring, 9" McCreary slicks, 5.13 Dana, 426 wedge street headers with a 3" exhaust snaking through the engine compartment and 24" under the car ran 12.5's. Was a stock eliminator car.

Pure stock 440+6 challenger making some runs....I'm sure there's some tricks done to make them run that good on polyglass tyres.

https://www.youtube.com/watch?v=gPbZLu8BgxM

13.50-13.80 @ 102-104mph.

May be able to squeeze a 12.99 with slicks.

Keep the 3.23's if it is a street car!

14.2 @ 100

Dizuster had 65 Belvedere. 3.91, stock 11 3/4" converter, Eddy heads, 484 purple shaft, stock 440 short block, maybe 8.0-1. With 255/60 BFG T/A's it would hook from 1500 rpm everytime. 12.90-13.0 depending on weather. Many different people raced it. All could cut .00x lights. Car was dead on. Best car in real street trim I've ever raced.
Doug

You can give two different people the very same parts and one guy can make it fly like a raped ape and one guy can't make enough power to spin the tires. Its been proven time and time again.

Back when they were new......

Popular Hot Roddjng tested a 71 440-6 Charger Super Bee with 4.10's/auto, it went 14.2@99.

Car Craft tested a 71 440-6 RR, also 4.10's/auto.....they got it to go 13.7@101.

I'd say those are the bench marks to shoot for.

Thank-You...


(Research what Tim Richards did with a lowly '71 GTX...

Why would a mild engine like that have aluminum rods??

A car like that with a typical driver will probably run 14's at the track. I see cars like that all the time at Mopar shows run 14's or 15's. Once in awhile you'll see a car that the owner is willing to beat on harder and they'll run 12's or 13's.

When I was in high school my best friend had a '70 RoadRunner with a 440+6. It was a four speed, Dana 60 car with air grabber. I don't know how fast it was in the quarter mile but we had a lot of fun ripping around town in that. It sounded killer and it pulled hard and it got a lot of attention.

Quit worrying and have fun you can tune it to the 13s if you are lucky Sticky tires are 12s less then sticky are 15s or higher Look at the trap speed that will tell you how much power you are really makingYears ago I ran a 16.2 at over 104mph

Not an apples-to-apples comparison by any means, but...

When I first bought my Challenger with the 440-6 on a stock '70 long block & MP 272/.455" cam, it was slippin' & slidin' to 13.7s at 101 on hard Goodyear 235/60R15s.

I put a set of M&H 275/60-15 bias-plies on spare 8" rims and it dropped to 13.2s at 103 simply due to better traction off the line.

The car had 3.55s and an OEM 2200-stall converter at the time. Too much gear and too much stall with marginal tires will just make it worse.

Headers or not?

Yeah, cheap 1.75", but still better than manifolds.

like everyone says, tires are the biggest problem.
If keeping the tires, switch to 3.23s or 3.55s, still will be hard to launch hard.
your 60 foot times will stink!
And you'd better have a good fuel system, or the top end will suffer.
With practice and a gear change I'd guess low 13s.
with slicks, high 12s should be easy,

Low 15's and mid to low 14's if its right with the right bite.

When I first got my heap running in 1982, I had a pretty mild 440 in it.
-.040 over 440 with flat tops .055 down the hole
-Crower "Monarch" 280H cam(224/224@.050, .460/.460, 110lsa)
-Stock 906's with upgraded springs
-ex manifolds with crimp bent exhaust pipes for a 383(no H pipe)
-Original Torker with a 650dp Holley
-12" converter
-3.23's
-g50-15 bias ply tires

At Sacramento raceway it would run low-14's at mid/hi-90's.
Best ever was like a 14.06....... And it never broke 100mph in that configuration.

I bought an A-12 in the spring of 69, one of the first around.
My buddy was a salesman at a Northeast Oh dealership.

Two other friends had Dodge A-12s, mine was a white RR with a black vinyl top, all 727s.

In pure stock we all ran pretty much the same, this with some re jetting, more timing and a pinion snubber (I know, I know).

At a local track, 13.6s, 106 with the Polyglas.

On mine, I did a multi-angle valve job, prestolite Ign. module, Hooker fenderwell exit headers, 50 cc pump, electric pump, windage tray w/6 qt. pan, more jetting and timing, 42* total on a recurved dual point, short point set for you guys as old as I am who remember that stuff, open headers.

Was able to run a best of 12.80s at 114, still Polyglas.

The trick to traction was easy roll-out and a slow mash.

Wish I didn't drive that wet cold January night in 1971 after a few drinks, my stupidness cost me week in the hospital and a totalled A-12.

Oh well....Joe

Edit.. forgot the SSH 25 Racer Brown hydraulic in the mods
Edit #2 160* thermostat, blocked heat crossover, my memory sucks!!
More, cool can, high vol. oil pump kit, 3/8" fuel line all the way to carbs J10 plugs, this is embaressing!!

It will come down to several key factors. How good are the heads really, is it truly 10.5:1 (pump gas won't work if it is), car weight, quality of your tune, driving skill, and DA on track day. Best- low 13 @ 106, worst 15.0 @ 100.

The cam is pretty small.

I think alot of the disparity in the quarter mile numbers come down to two things. #1 the particular motor, most off the assembly line weren't within 1 point of advertised compression, the set of heads,(valve job and port alinement. The cams installed centerline. The distributor setup.
The stars could aline correctly and you had a real firebreather or you could get a dog.
#2 the driver, most didn't know how to launch a car with limited traction.

When will this car actually go down the track?

the xe262 under cams the engine. 4.10's way over gear. 10.5:1 will never run on pump gas. I had a 9.3:1 engine with a 268/276 comp magnum replacement and it blew 195psi; really too high for reliable pump gas operation. i'd re-think the combo.

it has 3.23 gear right now if i remember reading correctly, run the car down the track with those gears.

Man, I don't know how many miles I rode (and occasionally drove) in my buddy's '71 Sport Satellite in the '80's... Your post brought up a lot of memories!

Honest answer to the question, about fifteen flat after a bit of practice. With sharp tuning and lots of seat time, somewhere in the fourteens in decent conditions.

Real world performance for an OG musclecar...

If you're still planning/buying... I'd consider more cam, maybe a little less CR. Especially with a craptacular stock 906 open combustion chamber - prone to ping.

That cam you mention would be a good street cam for a 8:1 318, IMO you would leave a LOT on the table running a tiny cam with 440". More duration would help with moving that torque curve to the right (4.10's will be very short with that 262 cam).

"But what about low end torque?"

What'cha going to do with all that low end torque from a big block? Hook up on those T/A's? Puh-leeeeze. Yeah, guys *have* got cars to launch on hard tires, but often with light torsion bars,shocks, etc... you know, all the stuff that makes a car a turd to drive on the street. And you mentioned T bars, AC, PS, iron manifolds, etc. This is probably a super nice car to roll in. And the very things that make it so good for that work against ya' at the track...

If it's already built... put some 2.54's in it and be the burnout KING! All joking aside, I would think seriously about keeping the 3.23 gears.

Oh, and like was mentioned by others, might wanna check that cranking pressure... octane may be an issue.