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Six Pack, Fuel Injection or 4BBL on a 340?


Mar, you kill me!

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.030" - .040" should do nicely, but remember, the best defense from pinging (as Gregory C found out) is to have the compression set for the available fuel. And on these older engines lacking 4 valve pent roof chambers we can't get away with 11:1.

I think I'll be following your lead on dealing with carbs and that crappy heat soak issue! But some things will get EFI for sure - at some point.

Oh, and six packs? Ughhhhh, leave that stuff on the shelf!! Total PITA to deal with repeated jet and PV changes. I'm up for Velcro carb gaskets and Velcro flare fittings.
 
Thanks Meep, always a pleasure and learning experience...........and Mario, I can always count on your comedy relief! You Gent's have a good weekend.
 
Corn Fuel...It's food people, not fuel!!!

*ahem* sorry, I digress...

I think EFI will be able to deal with today's fuels more efficiently than a carb will. :upside down:
 
I'm damn near ready to ditch the carbs in favor of EFI. Just sick and tired of the heat soak issues with this crappy non carb friendly gas. There really isn't a substitute for EFI if you want true drivability. Oh, you can always put on a turbo and mount the carb as a suck through far from any heat source!

I'm with you Meep. If and when I take the plunge into EFI it will be based on LS system (gasp). Parts are cheap and can be tuned with a laptop. Then down the road I can throw on a turbo I've always been dreaming about.
 
You can buy an EFI 6-pack setup for around $2000, but that's just for the top plate with throttle bodies, adapters and fuel rails with mounts, TPS, IAC, linkage, air cleaner adapters and gaskets. You still have to machine your own intake, and buy the rest of the missing parts of the system, including an EFI system controller (Fast XFI or EFI 2.0 etc). It's a large chunk of money any way you look at it... even for a thrifty do it yourself kind'a guy.

Unless a 6-pack EFI setup is simply a must have, I would look at the other "less expensive" alternatives.
 
A complete FAST EZ EFI 1.0 is under 1900 complete....check ebay.
 
Hey Prop, I don't know if this helps at all but I found this article a few months ago. I was thinking about following this build. Its a 340 rated at 500 hp and 500 lb-ft. I haven't done to much investigating and don't know much about engines so not sure how this rates among other builds. I priced everything really quick on from Summit (may be cheaper to shop around) but based off a stock engine it was only about a $5000 upgrade.

http://www.hotrod.com/techarticles/...mall_block_engine/dyno_test_engine_specs.html

Engine Specs
Engine type: Chrysler LA small-block
Displacement: 414.3 ci
Bore x stroke: 4.060 x 4.00
Compression ratio: 10.0:1
Deck height (actual): 9.580 in
Rod length: 6.123 in
Main- and rod-bearing clearance: 0.0026 in
Rod side clearance: 0.026 in
Crankshaft endplay: 0.006 in
Camshaft endplay: 0.005 in
Piston-to-wall clearance: 0.004 in
Piston ring end gap: 0.021 in First and Second
Piston compression height: 1.460 in
Piston dome volume: -21 cc
Piston deck clearance: 0 in
Head gasket (Fel-Pro 1008) compressed thickness: 0.039 in
Combustion chamber volume: 65 cc
Valves: 2.02/1.60 in intake/exhaust
Valvespring diameter: 1.46 in
Valvespring seat pressure: 150 lbs
Valvespring open pressure: 415 lbs
Camshaft: Hydraulic roller: 242/248 at 0.050, 110-degree LSA, 0.594/0.581 lift
Ignition timing: 32 degrees
Carburetor: Holley 750 cfm
Fuel: 93 octane unleaded
Main cap bolt: 90 lb-ft
Rod bolt: 65 lb-ft
Head bolt: 90 lb-ft
 
Quickfuel Carb easy peasy & Performance 101 good alum. intake, heat riser blocked off, good fuel system & pump with bypass regulator either way you go... Some cleaned up mild ported job, short side radius & bowl work, with matched springs ret. keepers seals, good quality valves & performance performance valve job, on the heads, decant camshaft, specific for your needs/usage, {matched converter & gears} some quality adj. rockers, good free flowing exhaust/with 1-3/4" headers & gauze air cleaner, hot ignition & good wires, quality balanced internals, Blah blah blah easy peasy 400+hp, don't over think it or over complicate it... If your thinking about a 6bbl try checking out http://www.fbthrottlebodies.com/ IMHO the 6bbl EFI isn't a whole lot more $$$ than a complete Holley 2300 Carb 6bbl set-up complete with linkage aircleaner carbs manifold etc. {$2000+ easily}, let alone a $2000-$2500+ or much more, Fastman or MSD or Holley EFI standalone system... The 6bbl EFI it still has the cool factor too... A single TB system is simple, port injectors are better but start getting more complicated & expensive too... But so is a simple Quickfuel single Holley style 4bbl for a weekend car, not used as a daily driver... light car, woman driver, probably easier on the skinny peddle than we are too... Good luck Prop what ever you ultimately decide, it ain't my $$$ being spent...LOL..., your a smart guy, you'll do the smartest thing for your needs... Can't add much more, you've gotten allot of good recommendations already...
 
Here's a six pack efi system I was thinking of getting until I found out the cost of replacing the injectors.

http://www.fbthrottlebodies.com/


LA6bbl%20sys3.gif440%206bblsys.jpg
 
Question for you guys.....

I'm building a '71 Dodge Dart for the wife and possibly a sell/trade (if she doesn't take to the car). The car was a run of the mill leaning tower of power with the grandma shifter on the tree, with a 904 auto rolling it off to church. Anyways, long gone is the /6 and a 340 is taking its place, along with a 4 speed and a hurst shifter. Main goal HP wise is 400-450HP

Being the car is sorta like an open canvas, I've been pondering several different ideas with the motor. One would be building the 340 into a zero deck, quench motor. Some decent ported closed chamber aluminum heads and probably a hydraulic roller. I do have a set of fully assembled X-Heads, but those seem to be more appropriate for someone going for the factory parts/performance vs. my power goals. So on to the fuel system, and I can't seem to make up my mind.

I've looked into the different fuel injection systems....F.A.S.T, Eddy, Holley, Atomic and spoke with some folks that have run them. All seem to be pretty happy, and a fuel injected 340 with a 4 speed sounds pretty neat. Down side is i'm probably looking just a bit north of 2.5K when all said and done.

Next would be the standard 4BBL. I'd lean towards the Quickfuel 780 Superstreet, with electric choke and vacuum secondaries. I'd have good street manner's, low maintenance and a carb that allows for some decent user tuning. The carb would probably be on top an Eddy Air Gap intake. Cost all said and done....Probably around $800-900, maybe $100 more for port matching.

Last and latest thing i've been tossing around is putting a six pack on it. Again, i'd probably be looking at just north of 2K, but hey...it's a six pack! A couple things that worry me is my ignorance with them & unaware how to tune, and can I tune it to 400-450HP? I'm guessing so. Another issue, parts..where to find them?

So, not to cut the car down, but it's never going to grab the popularity and resale of some of our more premier B-Bodies. It's the honest truth. Like mentioned, it's just a run of the mill Dart. I have to be honest with myself and come to the idea that the wife may not take to the car and selling/trading it may be a scenario down the road. So let me ask this, do you think adding a six pack would really propel the value of the car that much more than just a 4BBL? Or a Fuel Injected system for that matter? To put it blunt, if I stick 2K into a six pack or fuel injection, would that 2K stick to the selling price and I wouldn't go backwards? I Know, I know..a buyer will pay whatever he/she thinks it's worth, but i'm sure some of you probably have seen how adding EFI or a Six Pack plays out sales wise. There's gotta be somewhat of a trend.

I don't want to short change the wife's car...It's gonna Rock N' Roll either way, but this car falls more into a closely watched budget scenario vs. when I destroyed the bank account with the Roadrunner and Coronet ragtop before that. Also like mentioned, the money put into it can more easily be lost at resale vs. a roadrunner, superbee, charger ect..ect..

So just looking for some opinions here. If you had a Dart, had a goal of 400-450HP, a followed budget, a bit ignorant on EFI and six pack's, and limited on resale (if it came down to it).....Which route would you go?


Single four barrel.... edelbrock cheap easy dependable way to go.
 
My thinking is if its going to be the wife's car make it EFI. Hopefully with the EFI it will fire right up, not vapor lock and leave her on the side of a busy road.
From the reading I've read Id go with an EZ EFI 2.0

My thoughts as well....then if you decide to sell the car, just bang on a QF 780 like your original plan. save the EFI for another/next project. C'mon Prop, it ain't like this is your last project :icon_winkle:
 
Why not just build a bone stock 340? Reliable, good power, easy to tune.
 
Hey Prop,

I'm late to the party but figured I would offer something to think about.

I am going with fuel injection on my car (but it is not done yet so I can't speak to how good it is). The FI kit is one element, but then you may want to get a proper tank for the best fuel pump location too.

Both the Six pack and the FI setup would cost some coin. If you are not sure about how the wife will take to the car, why not start with a simple 4 barrel carb? If she doesn't take to the car, you are not out a bunch of money. If she DOES take to the car, then you can consider a Six Pack or FI. For a driver car, I have heard the FI setups are super nice - she might really like that IF she likes the car.

So maybe a two step process?

Just some thoughts for consideration...

Hawk
 
Thanks again for posting fella's. Lotta good stuff. As far as leaving the 340 bone stock, that's really not my style with these cars. Never really has. Nothing against staying NOS, just more of a guy that builds stuff into the car on how I want it, or in this case how the wife may want it. As far as the six pack EFI, well that would be the best of both worlds! Unfortunately way beyond the realm of what i'd want to spend for fuel delivery for this car. Pretty friggin awesome though! Wow!

Good points on put on the EFI and yank it later, as well as Carb it and EFI later if need be. Both are pretty good ideas. The problem I see with adding later is the other additional requirements for the fuel system that would need to be added down the road. Just thinking out loud here, but if I put EFI in off the bat and carb it for resale or some other reason later, I would have already installed or modified a fuel tank for EFI, as well as a return system/lines from front to back. Converting that to work with a carb would be pretty easy, but if I start with a carb all of that would have to be redone...that is of course if I build a carb fuel system that could crossover to EFI pretty easy off the bat. Hmmm. Both ways seem a good route.

I'd have to say i'm leaning towards the EFI off the bat....Couple reasons; One would be the resale. Digging more and more, the trend i'm seeing is the EFI Modified older cars seem to snag more money. I'm not a statistician and only looked at a 100 or so EFI modified cars, but the trend I see is about 10-15% gain in total resale. If that ended up being the case, I'd break even on the cost of EFI, if not gaining a little on top of it. 2) would be reliability...I have pretty good faith in the newer carbs, but I think most would agree they are more finicky when it comes to tuning, heat and quality of fuel. 3) Getting into something new...Like a lot of you guys I like to tinker with new things, see how they work, and possibly improve on something. That could quite possibly be the case with EFI. Might move me to a whole new level when it comes to how I approach the fuel delivery systems on these old cars moving forward.



Thanks again guys! And thanks for the article coronet340. Some real good power rolling out of that puppy. Thank you Bud and Car Nut for the link on that EFI Six pack!
 
How about buying a wrecked charger or challenger and putting the hemi in it along with all the electronics? Get the best of everything.
 
One final (?) thought.

When you build it, plumb it for fuel supply and return lines (easy and cheap), and maybe even customize a tank (with your skills) to have an in tank fuel pump (moderately cheap). This will work with a carb OR FI setup, and you can swap back and forth easily.

...just tossing out ideas to see what sticks...
 
Question for you guys.....

I'm building a '71 Dodge Dart for the wife and possibly a sell/trade (if she doesn't take to the car). The car was a run of the mill leaning tower of power with the grandma shifter on the tree, with a 904 auto rolling it off to church. Anyways, long gone is the /6 and a 340 is taking its place, along with a 4 speed and a hurst shifter. Main goal HP wise is 400-450HP

Being the car is sorta like an open canvas, I've been pondering several different ideas with the motor. One would be building the 340 into a zero deck, quench motor. Some decent ported closed chamber aluminum heads and probably a hydraulic roller. I do have a set of fully assembled X-Heads, but those seem to be more appropriate for someone going for the factory parts/performance vs. my power goals. So on to the fuel system, and I can't seem to make up my mind.

I've looked into the different fuel injection systems....F.A.S.T, Eddy, Holley, Atomic and spoke with some folks that have run them. All seem to be pretty happy, and a fuel injected 340 with a 4 speed sounds pretty neat. Down side is i'm probably looking just a bit north of 2.5K when all said and done.

Next would be the standard 4BBL. I'd lean towards the Quickfuel 780 Superstreet, with electric choke and vacuum secondaries. I'd have good street manner's, low maintenance and a carb that allows for some decent user tuning. The carb would probably be on top an Eddy Air Gap intake. Cost all said and done....Probably around $800-900, maybe $100 more for port matching.

Last and latest thing i've been tossing around is putting a six pack on it. Again, i'd probably be looking at just north of 2K, but hey...it's a six pack! A couple things that worry me is my ignorance with them & unaware how to tune, and can I tune it to 400-450HP? I'm guessing so. Another issue, parts..where to find them?

So, not to cut the car down, but it's never going to grab the popularity and resale of some of our more premier B-Bodies. It's the honest truth. Like mentioned, it's just a run of the mill Dart. I have to be honest with myself and come to the idea that the wife may not take to the car and selling/trading it may be a scenario down the road. So let me ask this, do you think adding a six pack would really propel the value of the car that much more than just a 4BBL? Or a Fuel Injected system for that matter? To put it blunt, if I stick 2K into a six pack or fuel injection, would that 2K stick to the selling price and I wouldn't go backwards? I Know, I know..a buyer will pay whatever he/she thinks it's worth, but i'm sure some of you probably have seen how adding EFI or a Six Pack plays out sales wise. There's gotta be somewhat of a trend.

I don't want to short change the wife's car...It's gonna Rock N' Roll either way, but this car falls more into a closely watched budget scenario vs. when I destroyed the bank account with the Roadrunner and Coronet ragtop before that. Also like mentioned, the money put into it can more easily be lost at resale vs. a roadrunner, superbee, charger ect..ect..

So just looking for some opinions here. If you had a Dart, had a goal of 400-450HP, a followed budget, a bit ignorant on EFI and six pack's, and limited on resale (if it came down to it).....Which route would you go?
Personnally, I prefer a carberated classic...six pac on a 340 usually are tough to get right..keep it simple if wife is on the fence and go with a single 4 bbl.....but....for ego and great comments...the 6 pac setup beats them all
 
One final (?) thought.

When you build it, plumb it for fuel supply and return lines (easy and cheap), and maybe even customize a tank (with your skills) to have an in tank fuel pump (moderately cheap). This will work with a carb OR FI setup, and you can swap back and forth easily.

...just tossing out ideas to see what sticks...

Real good idea hsorman. If I went the carburation route, i'd want a good return system anyways.

momma happy, everybody happy...lol

Yes sir!

Personnally, I prefer a carberated classic...six pac on a 340 usually are tough to get right..keep it simple if wife is on the fence and go with a single 4 bbl.....but....for ego and great comments...the 6 pac setup beats them all

Thanks Terzmo!
 
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