Estimated 1/4 mile - 71 Roadrunner 340 4 speed

[RemCharger]

I've raced some pretty stout 383s, but the 440 is the way to go in that application

 

[Hemirunner]

I raced in the 70's and my best 1/4 mile time was 10.44 with 160 mph. I am unsure about the mph but I always had a high mph. That was with a '68 Road Runner with a 383 bored .60 over, reworked ported and polished heads, milled to far with 13 to 1 compression, tarantula manifold, Holley Dominator, cam and Hooker headers. 11" slicks and a perfectly set up suspension. I lightened to 2,690 pounds which was a key factor. I was a 4 speed with 4.30 gears in a 8 3/4 rear end and I made the 4 speed into a crash box by grinding every other gear off of the 2,3,& 4th main gears. I did not do burnouts and I did not use a line lock. 90-10 shocks in the front, air shocks rear, spring clamps on the front half of the leaf springs to make them a solid "bar", and an adjustable snubber set 1/4" from the floor pan. You have to practice incessantly on your power shifts, shifting with your feet flat on the accelerator. Start slow with your if you do power shifts because if you miss you may blow your engine. Look. This was full race, all out, but you have the choice of duplicating what works, like the suspension. If you drive it on the street the 90-10 shocks mean avoid all potholes, the 5" wide front tires mean driving slow when you turn. Lightening the car means fiberglass hood (which I made). plexiglass windows, no hood hinges, no window mechanisms, no carpet padding, no undercoating, no rear seat, no frills. My time was set at 2,350 feet above sea level, so factored at sea level, it would be lower.

View attachment 1792564

View attachment 1792574

I’m running high 8s at 160 mph so it’s probably a much lower mph but a very cool car nonetheless.

 

[padam]

okay, spending a lot of time researching, now I see something that with my budget may actually benefit me
All 383s are forged crank, so that would mean they should be also all drilled for a 4 speed, right? Most of the 440s I see are all cast crank, so I would need to get a new one
That said, now I don't have to buy a new crank so that it'd work with my transmission, and the crank is just stronger too
How hard is it to push the power level I'm looking out of a 383? Or are the cubes for a 440 just that much more worth it
Anyone with advice here to give, I'm all ears for it

You’ll learn more from doing than asking.

 

[340runner]

You’ll learn more from doing than asking.

Well, today feels negative 8, it's gonna feel like negative 25 when the sun sets in 30 minutes, and I am not going to a junkyard looking for items freezing my balls off, and I don't think anyone is going to meet-up on marketplace. Right now, asking seems like a decent way to learn. I can do more when it warms up and I can actually drive

 

[Curiousyellow71]

You would be better of finding a good used steel crank. Buying a new crank you just as well buy a stroker crank. You don't necessarily need a crank cut for a pilot shaft bearing, look on Brewers website. Occasionally a used steel crank pops up. I got one a few years back from a forum member. Post what your wanting in the wanted section when your ready. Make sure it's a 6 bolt and not a 8 so you can use your flywheel.
Torque is what gets the car moving, which a 440 will make a lot more of. A 383 really isn't much bigger in displacement then your 340, a 360 based 408 would likely be a better fit then a 383.
Its 8 degrees here and feels like -12. Good day to dream and stay warm!

 

[340runner]

You would be better of finding a good used steel crank. Buying a new crank you just as well buy a stroker crank. You don't necessarily need a crank cut for a pilot shaft bearing, look on Brewers website. Occasionally a used steel crank pops up. I got one a few years back from a forum member. Post what your wanting in the wanted section when your ready. Make sure it's a 6 bolt and not a 8 so you can use your flywheel.
Torque is what gets the car moving, which a 440 will make a lot more of. A 383 really isn't much bigger in displacement then your 340, a 360 based 408 would likely be a better fit then a 383.
Its 8 degrees here and feels like -12. Good day to dream and stay warm!

yeah, this engine talk and honestly everything besides tires and rear end for the near future are dreams. People who say practice and doing gotta live in texas or something. I can't do **** driving my car right now, and even if its warm like a couple days ago had a peak, my car would fall away from how much salt they put down after a pile up a couple weeks ago. I haven't even test drove from when I replaced my motor mounts and operating lever for the trans. I tried pulling that rear end yesterday but it got cold to the point of my fingers not having the dexterity to hold the ratchet tight even with gloves

I love dreaming, always got big goals and gotta work towards it.

 

[Phantomx]

Those goals are no problem for a stock stroke 440.
You really have a good set up for the sb to bb swap. Just get a bellhousing like this. I see them used for 400-500 bucks. New price is hard to swallow. It has both engine patterns. It will also keep you safe.

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I did some quick googling and everything says this Lakewood 15335 is a big block only bell. It would be cool if there were a dual pattern bell, but I’ve never heard of one and this one doesn’t appear to be.
Travis..

 

[340runner]

I did some quick googling and everything says this Lakewood 15335 is a big block only bell. It would be cool if there were a dual pattern bell, but I’ve never heard of one and this one doesn’t appear to be.
Travis..

I did too, at least i should be able to use the same clutch + flywheel

 

[Curiousyellow71]

My bad.. I was looking at dual pattern bellhousing for a dyno. Probably wishful thinking.

 

[340runner]

I will look again. I may have been looking at a bellhousing for a dyno.

Yeah, I saw the post that I think you deleted, the LKW 77 251 is a dyno bellhousing. I wish they adapted one honestly, but I'll live with getting one whenever I swap engines, i do have a sfi clutch and flywheel already and im not throwing down insane figures so it's probably good for now

 

[Curiousyellow71]

Yeah, I saw the post that I think you deleted, the LKW 77 251 is a dyno bellhousing. I wish they adapted one honestly, but I'll live with getting one whenever I swap engines, i do have a sfi clutch and flywheel already and im not throwing down insane figures so it's probably good for now

Yes, you have good parts at least.

We have a small block 904 transmission behind a 440 in our 65 dart using a adapter plate from A&A transmission so I knew what a plate looks like with both patterns. I saw that lakewood bellhousing with both patterns and did not catch that it was for a dyno and not a 833. To bad it's not for a 833.

 

[340runner]

Yes, you have good parts at least.

We have a small block 904 transmission behind a 440 in our 65 dart using a adapter plate from A&A transmission so I knew what a plate looks like with both patterns. I saw that lakewood bellhousing with both patterns and did not catch that it was for a dyno and not a 833. To bad it's not for a 833.

Yeah, that is too bad, what even goes into it where lakewood couldn't design one for a a833? Looks like it wouldn't be the hardest thing, they got like halfway there the only thing i could think of is it'd be hard to seal up the mating surface between engine and bellhousing