Estimated 1/4 mile - 71 Roadrunner 340 4 speed

[dvw]

I stick and gas welded in high school. Had a Mig at the dealership. Taught myself at work. But never had my own welder until I was almost 50. I regret not learning earlier. It’s a must. Already started my grand daughter at age 13. Doing a Dana from scratch isn’t a beginner job. I wouldn’t worry about the 8 3/4 yet. The turbo motor; It started as a 1991 36o which wasn’t a Magnum. It was a one year only hydraulic rooler motor. The stock cam was reground, the heads were ported some, off the shelf forged pistons, E85 custom carb, 76 mm Chinese turbo, home made plumbing, rebuilt 727 with a trans brake. A very nice set of Menscer shocks, Cal Tracs, and 255 drag radials. With a 2.76 8 3/4 it went a best of 10.60s. With a 3.23 9.90s. The standard forged pistons sagged in the center. It got ported Eddy heads, .550” hyd roller, Victor intake, eagle rods, and custom Diamond pistons designed for boost, and 275 drag radials. . It also got a 3.54 Dana cut down from a F 250 pick up. I built that. Ended up running a best of 9.55@142 in street trim @3775lbs. It took a fair amount of engine and shock tuning to get there. Took a hell of an effort. Except for the Dana my son built everything except the turbo plumbing and roll bar. Which he horse traded a 518 trans that he built for the labor. Though this was really the first car he built all the build ideas were heavily researched. He was 35 when he built it.
Doug

 

[70bigblockdodge]

A very nice set of Menscer shocks, Cal Tracs, and 255 drag radials. With a 2.76 8 3/4 it went a best of 10.60s. With a 3.23 9.90s

This is the good stuff.
I like cake, and eating it to.
IMO (which is not on par with others with more knowledge) gears are for making a heavy, slow car a little faster.
If your car went "way" faster with 3.55 gears compared to 3.23/2.94 something else changed it was not all the gear.
4.10/4.30 sure you will pick up a decent amount if you have traction because your 60' improvements pay bigger dividends down track.
Also IMO 4.00 and lower gears are no good AT ALL for street car. You look ridiculous getting passed repeatedly by KIAs, Hondas, insert whatever **** box comes to mind. I really don't care how bad *** your car is, if it cannot keep up with modern traffic at less than 3500 rpm it is a miserable machine to drive for any length of time. Sure I ran 4.10 gears and 14" inch wheels on the highway (when the national speed limit was 55mph, yeah I'm old), that was a different time. Nowadays making more power is easier than it was then, overdrives are more plentiful/practical. That's the direction I would send my money if I was your age. Matter of fact my son is following that with his Super Bee. He just put a TKX in it will probably have to move to 3.55 from 3.23 as the cars gearing now maths out to 200+ mph. He is changing rocker arms for some more lift and better geometry. We will be driving it on power tour again this year and not at 50-60 mph. We will slap it back on the dyno again and probably make a couple of passes at the drag strips on the tour. So here's to getting over 400 rwhp and traction and heat limited runs in low 13s. Yeah we know it should run better but with hard street tires and limited track prep at these stops you take what you can get and hope to see big mph.
Good luck young man, I wish I had these resources at your age, would have saved me a lot of money and time.

 

[340runner]

Is your RR a original 340 car? Engine have matching numbers? Just thought I'd ask because for what your wanting to do you may want to enjoy your 340 as is and build your first engine on the side...and do a stroked big block. It would be a easy swap. They make a 4 speed bellhousing that has both SB and BB patterns.
What year is the van? 8 luggage wheels or 6? Modern Dana's can have really thick axles and instead of a 3" they can be larger. You will also find S60's and dana 70's. They all can be cut down but its extra work and not the same as a older Dana 60 rearend say out of the 1960s. Anyway, I don't know what your looking at..do research on it. The internet is your friend.

It's a 2006 chevy express van 2500, with 8 lug tires, and I've seen online that while the OD might be different, the ID should be the same so it all kinda still works together. I'm fine with it not being EXACTLY the same as a dana from the 60s, as long as the case cover looks the same and it's just as strong.

I've thought about a big block as it's actually easier to find for less money than a 340, and about the same as a 360. Where would you start though, with a 383 400 or 440 as a block? I know some have the raised deck like the 440 but that shouldn't matter fit wise.
What would you say is possible power wise out of the big block keeping it NA or within a 100 shot without needing race gas?

As for swap, is it just removing the old engine and dropping in the new with a new bellhousing? I believe in 71 they use the same K member and even the same mounts so is it just the same? I already have a champion 26 inch radiator, so I'm not worried really about cooling.

 

[Hemirunner]

Well, I'm not sure if cooper cobras are good, they're hard as a rock, made a lot of smoke and still practically new tread while being horrendous in the rain, i remember driving to work and almost got perpendicular with the road without even stepping on it. I'm either in between bias ply slicks on a second set of wheels since I heard drag radials don't play with stick shifts well, or just run the et streets. I finally had to get a daily for over the winter so I don't drive the car in rain or any inclement weather by choice. Dailying the roadrunner with AC deleted and the heater core removed was hell

Second note, not sure if Byron Dragway would classify the ET street s/s as DOT street tires, need to run them in my planned class so that would also influence my decision

I’ve been 1.37 sixty on that tire at Byron. It’s considered a DOT tire. We’ll be back there this spring for the CISCS races.

 

[340runner]

I’ve been 1.37 sixty on that tire at Byron. It’s considered a DOT tire. We’ll be back there this spring for the CISCS races.

Auto or 4 speed?
I need to play with it definitely. You've been at byron before, do you know for their classes that require DOT street tire if street legal drag radials would count?

 

[Hemirunner]

Auto or 4 speed?
I need to play with it definitely. You've been at byron before, do you know for their classes that require DOT street tire if street legal drag radials would count?

Full manual 727 w/trans brake and lots of power. DOT drag radials count as a street tire, but you’re gonna have a rough go with that 4spd. Been there, done that, went 727 and haven’t looked back.

 

[340runner]

Full manual 727 w/trans brake and lots of power. DOT drag radials count as a street tire, but you’re gonna have a rough go with that 4spd. Been there, done that, went 727 and haven’t looked back.

Agh, I just can't bring myself to swap in a 727, the 4 speed is just so addicting, it's like a drug

 

[Hemirunner]

Agh, I just can't bring myself to swap in a 727, the 4 speed is just so addicting, it's like a drug

I get it but so is going fast and you can’t go fast until you get a slipper clutch and a race trans or put an auto in it. Once you let off a trans brake button, you’ll be hooked!

 

[Curiousyellow71]

It's a 2006 chevy express van 2500, with 8 lug tires, and I've seen online that while the OD might be different, the ID should be the same so it all kinda still works together. I'm fine with it not being EXACTLY the same as a dana from the 60s, as long as the case cover looks the same and it's just as strong.

I've thought about a big block as it's actually easier to find for less money than a 340, and about the same as a 360. Where would you start though, with a 383 400 or 440 as a block? I know some have the raised deck like the 440 but that shouldn't matter fit wise.
What would you say is possible power wise out of the big block keeping it NA or within a 100 shot without needing race gas?

As for swap, is it just removing the old engine and dropping in the new with a new bellhousing? I believe in 71 they use the same K member and even the same mounts so is it just the same? I already have a champion 26 inch radiator, so I'm not worried really about cooling.

It sounds like the van axle would work. I am not familiar with every dana so actually look at it and count the cover bolts. 10 bolts for a dana 60, I also assume is a semifloater(no wheel hub) and the tube od is 3.125 (measure it). A 8 3/4 can take a lot abuse for now. It's probably not a good place to learn how to weld.

You can get a big block water pump housing for your current radiator.
As far as a affordable starter engine, it's hard to beat a 440.
If your wanting to do a stroker then a 400 or a 440 are both good choices.
340s have always brought pretty good money, they did not get installed in may cars. 360s were mass produced and the cheapest choice.

 

[340runner]

It sounds like the van axle would work. I am not familiar with every dana so actually look at it and count the cover bolts. 10 bolts for a dana 60, I also assume is a semifloater(no wheel hub) and the tube od is 3.125 (measure it). A 8 3/4 can take a lot abuse for now.

You can get a big block water pump housing for your current radiator.
As far as a affordable starter engine, it's hard to beat a 440.
If your wanting to do a stroker then a 400 or a 440 are both good choices. 400's are supposed to be a little stronger. On the street a 440 has more longevity.
340s have always brought pretty good money, they did not get installed in may cars. 360s were mass produced and the cheapest choice.

I'm not getting rid of my 340 and selling it, it's numbers matching like the trans
I was thinking a 440, how hard would it be to pump one up to 550-600hp/tq. Do you think stock cast bottom end with new pistons, either ported or aluminum heads, and a good intake/carb choice, headers and cam plus a 100 shot if needed would get it there?
I couldn't imagine a 440 not getting there on stock cubic inch, even if its aftermarket bottom end

 

[Curiousyellow71]

I'm not getting rid of my 340 and selling it, it's numbers matching like the trans
I was thinking a 440, how hard would it be to pump one up to 550-600hp/tq. Do you think stock cast bottom end with new pistons, either ported or aluminum heads, and a good intake/carb choice, headers and cam would get it there?
I couldn't imagine a 440 not getting there on stock cubic inch, even if its aftermarket bottom end

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.

 

[340runner]

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.

View attachment 1792413

Yeah, I saw the photos of people's legs with clutch in them and **** and was thinking that I should get that for myself even with my motor, just added security. Wouldn't want to be forced to use a auto trans because I only have one leg, or just die from the clutch or flywheel going bye bye

 

[340runner]

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.

Would you run aftermarket rods or crank? I'd like to go internal balance, it's what I know and it sounds more simple. But, if I am getting another rotating assembly should i just go to a stroker kit. If its a choice, I'd like to get a rotating assembly that's balanced already, to not to put too much into the machine shop.

 

[Curiousyellow71]

Would you run aftermarket rods or crank? I'd like to go internal balance, it's what I know and it sounds more simple. But, if I am getting another rotating assembly should i just go to a stroker kit. If its a choice, I'd like to get a rotating assembly that's balanced already, to not to put too much into the machine shop.

The drop in strokers will cost you more..it just depends on your budget. Overall it's hard to beat a 500+ engine for a fun&fast driver.
Internally balanced rules out a cast crank, and would not make sense since you have a flywheel. A oem 440 steel crank is fine if you can find one. H beam rods would be a good idea, especially w nos. We have gotten by with stock rods, 2355 speed pro pistons wo balancing. That is likely the minimum engine I would do. Generally speaking lighter pistons and rods aren't expensive to balance because they won't be adding weight, they remove weight by drilling. Every upgrade you do gets you closer to a drop in stroker kit. That is a big reason why they are popular. I have never regretted stroking a engine. But, I have also been happy with 440 cu inch engines.

 

[70bigblockdodge]

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.

View attachment 1792414

Relating to this topic, rpm is tough on parts. While a scatter shield is a good choice, buying quality clutch components is a must with launching and high rpm. Billet flywheels are expensive, cast steel is asking for trouble. Same goes for clutch and pressure plate, cheap ones are not really intended to go 7k. Then throw in the made in China part, IMO my worn out 58 y.o. legs are still worth spending $$$$ on a good clutch. $7-800 bucks on a quality clutch combo is right on par with a average/regular converter which can easily go over a thousand plus.

 

[340runner]

The drop in strokers will cost you more..it just depends on your budget. Overall it's hard to beat a 500+ engine for a fun&fast driver.
Internally balanced rules out a cast crank, and would not make sense since you have a flywheel. A oem 440 steel crank is fine if you can find one. H beam rods would be a good idea, especially w nos. We have gotten by with stock rods, 2355 speed pro pistons wo balancing. That is likely the minimum engine I would do. Generally speaking lighter pistons and rods aren't expensive to balance because they won't be adding weight, they remove weight by drilling. Every upgrade you do gets you closer to a drop in stroker kit. That is a big reason why they are popular. I have never regretted stroking a engine. But, I have also been happy with 440 cu inch engines.

I'm thinking right now the combo i want is a 440, probably from a motorhome or something, for around 500$ steel OEM crank, one on marketplace thats 275$ but it needs work probably stock rods but maybe H beams 650$ and pistons which are around 700$, intake for around 400$, and heads which I'm still deciding

Relating to this topic, rpm is tough on parts. While a scatter shield is a good choice, buying quality clutch components is a must with launching and high rpm. Billet flywheels are expensive, cast steel is asking for trouble. Same goes for clutch and pressure plate, cheap ones are not really intended to go 7k. Then throw in the made in China part, IMO my worn out 58 y.o. legs are still worth spending $$$$ on a good clutch. $7-800 bucks on a quality clutch combo is right on par with a average/regular converter which can easily go over a thousand plus.

Well, that's why I use the mcleod clutch kit and flywheel I do, I have a street extreme and the steel flywheel, it was about 800$

 

[Curiousyellow71]

340 clutch and flywheel parts should go right on a 440 with a steel crank. Beware, not all rv engines had a steel crank. The first 440 we swapped in was out of a '75 RV and had a cast crank. I was 16 or 17. That was a few years back.Lol

 

[340runner]

340 clutch and flywheel parts should go right on a 440 with a steel crank. Beware, not all rv engines had a steel crank. The first 440 we swapped in was out of a '75 RV and had a cast crank. I was 16 or 17. That was a few years back.Lol

thats actually great to know, I thought they didn't so I was going to figure in new clutch and flywheel price. Keeping the stock rods, a new crank is 600$ and new pistons are starting to figure the way out, just need to do everything else before i work on an engine, tires ain't cheap.

 

[ROYSTOLL2]

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.

 

[340runner]

It sounds like the van axle would work. I am not familiar with every dana so actually look at it and count the cover bolts. 10 bolts for a dana 60, I also assume is a semifloater(no wheel hub) and the tube od is 3.125 (measure it). A 8 3/4 can take a lot abuse for now. It's probably not a good place to learn how to weld.

You can get a big block water pump housing for your current radiator.
As far as a affordable starter engine, it's hard to beat a 440.
If your wanting to do a stroker then a 400 or a 440 are both good choices.
340s have always brought pretty good money, they did not get installed in may cars. 360s were mass produced and the cheapest choice.

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