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

Propwash

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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?
 
I'd stick with the single 4 barrel setup if it was mine Will. I don't think the 'wow' factor of having a 6-pack would ever come close to recouping your original investment, and you wouldn't see to much of a hp gain either. Plus you know how to setup and tune the Quickfuel. I've heard of a lot of problems getting the 6-packs setup if you don't work on them everyday.
 
I was thinking the same thing elk, especially if there is any chance you are going to sell it Will. I wouldn't mind trying some of that newfangled aftermarket fuel injection but it's just a little to rich for my blood. I always had a thing for those Darts so it should be a fun build.
 
Throttle body injected or sequential port injection?

If you went throttle body injected and the wife didn't dig the car, you could rip the EFI off and put on a craigslist 4bbl and then sale the car. Keep the EFI for something else or sell it to someone here.
 
I've been hearing about a six pack EFI system, could look into that.
 
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
 
just save the $$$ and run the 4 barrel.you will never recoup the cost of the fi or 6 pac.you already know how to tune the carb and no extra install hassles either.a well tuned carb will be just as reliable as the fi.sure its cool to say"its fuel injected or six pac",but is that really worth an extra $1200 or so in the build?could the $$$ be spent some place else for better effect?
 
Im with Gpuller on this one, Will. EFI all the way. peace of mind the missus aint guna get stuck anywheres. and like Jim Bob says, you could sell the EFI separately and recoup some $$$ if you wanted/needed to
 
I would go with the EFI. You would be fine with a throttle body unit. You can get the new fuel mini tank set up from Edelbrock where you don't have to buy a special pump or have a special fuel tank. You can mount it at your radiator like a overfill tank. It seems to be working great for everyone that has used it. I am working on getting an EFI port injected six pack set up for a 70 6 pack Cuda I have. You are looking at around $4,500 to set up one properly.
 
I really like the idea of EFI for this build. Despite the cost I think it would make it different and more desirable for re-sale if it did go that way. Your wife also may like the idea of it better. If not then I would lean 4 barrel... To me 6-pak's belong on big blocks
 
I try a cheap 600 eddy first. Just to see if she likes the car. If she fall in love with it, then go with the efi. Todays gas is to shitty with a carb. for a lady. 20 mins. in a store, come out and car floods from fumes under the hood.
 
A few comments....

Do you want the car to run a bit hotter than stock or really be a killer? This is the wife's car so what sort of ride is she after and does she really need 400 HP? Or will a good 375 do? My thought is I built a pretty simple 340 Dart long ago that would burn the rubber of the rims as long as you had gas in the tank. Iron 73 heads with 2.02's, hemi grind cam, LD 340 type intake, headers, holley 600 DP. Car ran high 13's on 78 series half bald street tires on the original 14" wheels.

If it were me I'd go simple but add EFI. Keep the iron heads because they work well on the street in the RPM range that the car will spend most of it's life in. Larger port aluminum heads are for higher RPM power or for strokers IMO. Put some good iron adjustable rockers (or equiv) and some 3/8" push rods to help with valve train stability with more spring. Send the heads to Jim (IQ52) for a basic port job and rework including hard seats, 9.5:1 CR max, get the aforementioned cam, if no EFI than a street calibrated carb (570 - 625 CFM should do well), good dual plane intake (air gap is popular), quick curve in the distributor with MSD or Chrysler electronic, headers are a must IMO, 2.5" pipe all the way out, 3.23 gears - or 3.55 if she wants to be a bit racy. If you want to sell later the EFI should help the sale if it's all dialed in and the car runs great. Or pull it off and slap on a Holley to sell it and save the EFI for another car.

This can be a really cheap and effective build. My 69 GTS convertible is bone stock and it runs pretty damn good. Those 340's mean business and even more serious with a small tweak in the cam dept.

Forgot to mention we just put on a deep pan with a HV oil pump. A bit more oil pressure isn't so bad if you have looser clearances. You might also get rid of that oil squirt bolt at the front of the engine that lubes the timing chain and possibly a grooved #4 cam journal to feed a bit more oil to the rockers.
 
Thanks for the feedback fella's. I appreciate it and am glad I posted this thread, because you guys came out with a lot of different aspects/scenario's that I didn't even think of...so thanks!

A few of you brought up the point basically "stick with what you know", and that's a real good point. I really like the quickfuel carb's. With their quality, reliability and tunability, they've really changed what owning, operating, tuning and maintaining a carb is all about. I wouldn't have to worry about some of the additional requirements that a EFI system would bring. Cost is on the low side of the spectrum. No bells..No whistles, but a decently tuned 4BBL on the 340 would make most anyone happy. I would have to focus on eliminating carb heat sync issues and reliability like you guys mentioned (for woman drivability). Additional work for carburation would probably roll out to phenolic carb spacer, possibly blocked heat crossovers and a return system instead of deadheading it. That with a decent vacuum based tune, that should get me free and clear of heat/lock/flooding issues....but again, glad you guys brought it up, because that all add's to additional costs.

On to the EFI... I'm glad to see the feedback one way or the other on that, being I have no real world experience with the aftermarket systems out there. It would be a throttle body set up, not the single point injection. Even though that would be pretty cool having single point, it would be way over the top for this build. Looks like a common consensus on EFI is "reliability". I guess with every car running it now days and have for years, EFI has proven itself when it comes to reliability. Myself I wouldn't be too worried about the additional requirements and install. I've installed a couple bypass regulator systems with return to the tank in the past (to eliminate fuel heat-percolation and vapor lock). What would be left..A controller, wiring, fuel pump and O2 sensor? And thanks for the tip on the mini fuel tank challenger6pak, didn't even know that existed. Good points on the remove and resale as well. Sounds like if I left it on, it could be a selling point but may/may not recoup itself. Reliability will be there, and I imagine I would gain some efficiency.

With the almighty six pack.....well, not a whole lot of big pluses rolling out of that one here. I spoke with my uncle today who had an Challenger T/A back in the day (yes, kicks himself in the *** for selling it every day since). He's a pretty straight forward guy and basically told me that don't bring it to him, to help tune it or get it running just right, because it's like trying to tune up a battleship, blindfolded with a cresent wrench...lol I gotta respect his honesty. I also dropped off the 340 at the engine shop this afternoon to get it boiled and mic'd out. Spoke with the owner on six pack's and he said..."No".....and that's about all he said. I think if this car was a Challenger or Cuda, popping the hood to reveal a 340 Six Pack would be cause for applause and add resale. Popping the hood on a Dodge Dart and revealing a Six Pack would gain somewhat of the same, but would probably also draw "what the hell is that doing there?" So, talking with you guys and a few other folks, what the six pack idea looks like is: high cost, extensive learning curve for tunability, limited tunability, finding parts, a negative on the resale.....but still holds the best bling factor.


Thanks again guys for your input, keep it coming! The amount of knowledge/experience and people willing to share it, is what makes this place so awesome. Thus far, i'd say the Six Pack is out of the mix. Cool idea and I love the mystique of them, but just not seeming to be a good fit for this build or the little woman that would be sitting behind it. The Carb vs. EFI is still a toss up. Great points were made about reliability, and the last thing I want is my wife on the side of the road or stuck in a parking lot. But also like mentioned, correctly tuning in a carb and safeguarding it against its known quirk's, should get the car in close relation. Carb set up would be a little cheaper and I wouldn't need to focus on recoup from its expense. EFI would be low maintenance and may/may not pay for itself. So still hanging out there a little guys...tough decision!

- - - Updated - - -

A few comments....

Do you want the car to run a bit hotter than stock or really be a killer? This is the wife's car so what sort of ride is she after and does she really need 400 HP? Or will a good 375 do? My thought is I built a pretty simple 340 Dart long ago that would burn the rubber of the rims as long as you had gas in the tank. Iron 73 heads with 2.02's, hemi grind cam, LD 340 type intake, headers, holley 600 DP. Car ran high 13's on 78 series half bald street tires on the original 14" wheels.

If it were me I'd go simple but add EFI. Keep the iron heads because they work well on the street in the RPM range that the car will spend most of it's life in. Larger port aluminum heads are for higher RPM power or for strokers IMO. Put some good iron adjustable rockers (or equiv) and some 3/8" push rods to help with valve train stability with more spring. Send the heads to Jim (IQ52) for a basic port job and rework including hard seats, 9.5:1 CR max, get the aforementioned cam, if no EFI than a street calibrated carb (570 - 625 CFM should do well), good dual plane intake (air gap is popular), quick curve in the distributor with MSD or Chrysler electronic, headers are a must IMO, 2.5" pipe all the way out, 3.23 gears - or 3.55 if she wants to be a bit racy. If you want to sell later the EFI should help the sale if it's all dialed in and the car runs great. Or pull it off and slap on a Holley to sell it and save the EFI for another car.

This can be a really cheap and effective build. My 69 GTS convertible is bone stock and it runs pretty damn good. Those 340's mean business and even more serious with a small tweak in the cam dept.

Forgot to mention we just put on a deep pan with a HV oil pump. A bit more oil pressure isn't so bad if you have looser clearances. You might also get rid of that oil squirt bolt at the front of the engine that lubes the timing chain and possibly a grooved #4 cam journal to feed a bit more oil to the rockers.

Thanks for tuning in and adding Meep..You helped dial in my 512 build and I appreciate all the real world experience you have to offer. As far the the HP goal, that's a number I set. With how the wife likes to drive, I think that would suite her fancy pretty well. Little speeder! Knowing how the bird & other cars of mine ran, with their HP/TQ, weight and configurations....it's a number where i'd like to see the car perform at. I hear where you're coming from on the 375HP. Talking with several different folks, that seems to be around the threshold where you cross a line from working with what you got on a 340, into stepping into higher performance parts and obviously higher expenses. I have caught myself leaning towards the last engine build, the 512 and I have to refrain from doing that with this car. Hard to do once you tasted that speed/power, but a quick reality check of a budget and the little 100lb woman that would be driving it, quickly brings reality back to the table.

As far as the heads go, I spent a good amount of time speaking with the local head guru. Like mentioned, I'd be crossing that threshold and trying to make the iron heads perform the same as aluminum would cost me just as much, if not more than just buying a set of performance aluminum heads. I believe he mentioned having to machine down under the springs, to support beefier springs, obviously different seats, fancy foot work porting around the bad humps in the runners and exhaust, as well as just buying decent springs, locks retainers and seals. One thing i'm worried about is butchering these heads and then not being happy with there performance. I'd also have to toss out the idea of a decent quench set up or notching up the comp. With that being said and going the warmed iron head route, my wife running 13's would be quite the site to see...lol My luck, she'd peel by me in the bird somehow or another and I would literally never hear the end of it.

Thanks for the heads up on the oiling system. Real good stuff. I'll save that for the build.
 
Just to add, I'm not sure if I'd get too wrapped up in the heads. Single springs with a damper on a smooth cam profile will work well. No need to cut spring seats and can use umbrella seals. Bronze guides, hard seats and some rigid valve train components will go a long way. The SB heads have a small quench area as well, similar to the 906 head, and if you run a zero deck flat top you will be OK. Need to do the math to see if the volumes equal 9.5:1 CR. Also iron heads won't require the MLS gaskets so more money saved. The Dart is quite a bit lighter than a B body so a performance gain right there. Do more with less! Oh, and the 100 lb wife is a step in the right direction too!

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!
 
Meeps is da Man!!

sammy.jpg
 
Just to add, I'm not sure if I'd get too wrapped up in the heads. Single springs with a damper on a smooth cam profile will work well. No need to cut spring seats and can use umbrella seals. Bronze guides, hard seats and some rigid valve train components will go a long way. The SB heads have a small quench area as well, similar to the 906 head, and if you run a zero deck flat top you will be OK. Need to do the math to see if the volumes equal 9.5:1 CR. Also iron heads won't require the MLS gaskets so more money saved. The Dart is quite a bit lighter than a B body so a performance gain right there. Do more with less! Oh, and the 100 lb wife is a step in the right direction too!


I hear ya! Roadrunner looks like King Kong sitting next to the Dart. The wife, yeah...i'm just shy of being two of her. So, would it be safe to say that I would want quench to fall in the 35-40 area with these opened chambered heads? I'll circle the wagon on these heads with your advice and swing IQ a line. I'm already halfway there and have a set of heads, so it's worth a second look. Thanks for piping up.


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!


Know the feeling Meep...Like others, I battled the same on the Coronet. Phenolic spacer and blocked heat crossovers just about got rid of it. I think if didn't have an Edelbrock carb on it, it probably would just be a faint whisper on really hot/traffic burden days. Roadrunner has blocked crossovers, a spacer, no eddy carb, thermo wrapped lines and a return fuel system...0 heat soak issues, even with that corn whiskey they're selling around here (which I obviously try to avoid running). Sucks to have to pay that price, just to battle crappy fuel.
 
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