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Xpock182
05-18-2015, 12:32 PM
Hey guys I just picked up a 69 Camaro Pro Touring and had a few questions regarding the motor.

Seeing as how I can not get in touch with the original engine builder I would really like some advice from some of our members.

Here's a list of the stats that I have regarding the motor...



540 Cubic Inch Dart Engineering V8
Aluminum Dart Pro 1 Heads
Two Edelbrock four barrel carburetors
Eagle Crankshaft
Eagle H-beam Rods
Eagle domed and forged Pistons
Tremec TKO 600 Transmission
MSD Blaster 2 Coil
MSD Pro Billet Distributor
MSD Ignition box
Custom grind Lunati Voodo cam
Lemons headers
Double roller timing set


Disclaimer- I wish I had more statistics on the parts listed above but unfortunately this was all that was provided to me when I purchased the car. Flame suit is on take it easy on me..

:thankyou:

Here is a list of questions I have...


What kind of Fuel Pump would you recommend for the duel Edelbrock carburetors & what fuel pressure would that provide?
I've seen 540 Dart motors with one carb and i'm curious as to why they put two on mine
What is the recommended redline for this set up?
What weight oil should I be using?


https://dealeraccelerate.s3.amazonaws.com/images/4/1/3/7/4137/1969-Chevrolet-Camaro_293731_low_res.jpg

https://dealeraccelerate.s3.amazonaws.com/images/4/1/3/7/4137/1969-Chevrolet-Camaro_293732_low_res.jpg

https://dealeraccelerate.s3.amazonaws.com/images/4/1/3/7/4137/1969-Chevrolet-Camaro_293728_low_res.jpg

https://dealeraccelerate.s3.amazonaws.com/images/4/1/3/7/4137/1969-Chevrolet-Camaro_293758_low_res.jpg

https://dealeraccelerate.s3.amazonaws.com/images/4/1/3/7/4137/1969-Chevrolet-Camaro_293763_low_res.jpg

Since the images were taken all I have done is replaced the battery with an Optima.

AMSOILGUY
05-18-2015, 07:06 PM
Www.dartheads.com for a telephone number they may be able to help you? I bet they liked saying it's a dual quad set up. Or simply liked the way it looked. As for oil I wouldn't run anything with less viscosity then a 30. Not knowing clearances and just guessing I'd run 10W40. With that said I'd run something with a formula that will protect during storage as well as run time. Not all oil will do that.
Where are the pictures?

Xpock182
05-19-2015, 05:07 AM
Www.dartheads.com for a telephone number they may be able to help you? I bet they liked saying it's a dual quad set up. Or simply liked the way it looked. As for oil I wouldn't run anything with less viscosity then a 30. Not knowing clearances and just guessing I'd run 10W40. With that said I'd run something with a formula that will protect during storage as well as run time. Not all oil will do that.
Where are the pictures?

I will post some pictures up today in hope that it will get a bit more attention. Thank you very much by the way, I do not plan to store the car too often. Hopefully I will put around 1500-2500 miles a year on her.


I actually called Dart before I created this thread. The guy literally told me that they just make the motors and that I needed to contact my engine builder. :smiley_smack:

AMSOILGUY
05-19-2015, 05:30 AM
How about some of the rest of the car.. Looks like a lot of nice parts went into the build from those pictures.

GregWeld
05-19-2015, 07:17 AM
Don't mean to bust your bubble but that car is NOT Pro Touring with a 4 bar rear end - it won't turn - it's made for going straight not turning. Pro STREET is a better description. Dual quads aren't a particular "performance" enhancement... they're cool looking - and "might" get you some more dyno numbers... but a well tuned single carb would most likely produce better numbers. Having said that - they always LOOK cool.


Post up some other pics of the car... what else does it have?

Vegas69
05-19-2015, 07:48 AM
You will need a minimum of a 150 gph pump with less than 7 lbs of pressure.

I'd start with a 10w30 and look at your oil pressure, hot at idle. If it's below 15-20, bump it up to a 10w40 or 15w50. Us a detergent oil as mentioned.

Redline is likely around 6200 with a hydraulic cam, 6500 with a mechanical.

Unless things have changed, Edelbrock's biggest carb is 750 cfm. That's to small for a 540. I agree that people think they look cool but you will need to go to a holley if you want to swap to one carb. I'd take a good look at the plugs if you think it's not running correctly.

Call the car what you want. :catfight:

Xpock182
05-19-2015, 08:17 AM
Don't mean to bust your bubble but that car is NOT Pro Touring with a 4 bar rear end - it won't turn - it's made for going straight not turning. Pro STREET is a better description. Dual quads aren't a particular "performance" enhancement... they're cool looking - and "might" get you some more dyno numbers... but a well tuned single carb would most likely produce better numbers. Having said that - they always LOOK cool.


Post up some other pics of the car... what else does it have?


Here are a few pictures, I will get better ones of the body. The interior needs some work in my opinion and I plan on addressing it over the next couple of months. I appreciate the advice GregWeld!

I am new to this form as well as some of the terminology. However I have had some experience in the past with track driven cars. My previous "hobbies" were a 2005 350z & a 2008 M3.The 350z had Stoptec 6 piston BBK and a built motor with 18g Greddy Twin turbo kit, along with many other modifications for the occasional track day. The M3 had an ESS V600 Supercharger, StopTec BBK, Akrapovic exhaust & BBS Wheels. Made great power and was a lot of fun to drive!


Unfortunately both of those cars had to go when I had youngest boy. So this car is my first attempt back into the "Car Hobby"

Hopefully I don't get to much hate for my Previous Imports. :shakehead:

Xpock182
05-19-2015, 08:21 AM
How about some of the rest of the car.. Looks like a lot of nice parts went into the build from those pictures.

The Iphone pictures dont do much justice above. I will be sure to take some good ones. The real work in this car appears to have gone into the Powertrain and the body work. The Vents in the hood are a nice touch along with the "shark fin" louvers are "functional" I'll have to take closer pictures when I get to the house with a camera better than my iphone...

Xpock182
05-19-2015, 08:21 AM
You will need a minimum of a 150 gph pump with less than 7 lbs of pressure.

I'd start with a 10w30 and look at your oil pressure, hot at idle. If it's below 15-20, bump it up to a 10w40 or 15w50. Us a detergent oil as mentioned.

Redline is likely around 6200 with a hydraulic cam, 6500 with a mechanical.

Unless things have changed, Edelbrock's biggest carb is 750 cfm. That's to small for a 540. I agree that people think they look cool but you will need to go to a holley if you want to swap to one carb. I'd take a good look at the plugs if you think it's not running correctly.

Call the car what you want. :catfight:


This is what I needed!! Thank you!

Ketzer
05-19-2015, 10:11 AM
Welcome to the forum.
This place is pretty LS heavy but there are a few of us that still love a healthy big block. You'd also be pretty surprised at what else some have in their garages besides a musclecar! Real car guys like all cars.


Jeff-

Xpock182
05-19-2015, 11:14 AM
Welcome to the forum.
This place is pretty LS heavy but there are a few of us that still love a healthy big block. You'd also be pretty surprised at what else some have in their garages besides a musclecar! Real car guys like all cars.


Jeff-

Thank you for the kind welcome!


I have reviewed many forums and this one appears to have the most active & available information along with a large member base. Not to mention some awesome rides! Hopefully my big block fits in well here despite all the epic LS motors :welcome3:

Neil B
05-19-2015, 01:49 PM
Is that a street car with a 540 big block, a 3.5" exhaust and NO mufflers? Holy crap, what does it sound like?:D

Flash68
05-19-2015, 01:51 PM
Is that a 540 big block with a 3.5" exhaust and NO mufflers? Holy crap, what does it sound like?:D

Good catch.. :eek:

now we really need some video or sound clip!

Xpock182
05-20-2015, 05:51 AM
Is that a street car with a 540 big block, a 3.5" exhaust and NO mufflers? Holy crap, what does it sound like?:D

I will be sure to take some videos as soon as I get the last few things patched up on the car. It does have mufflers however :D but it is 3.5'' exhaust :)

Xpock182
05-20-2015, 05:59 AM
You will need a minimum of a 150 gph pump with less than 7 lbs of pressure.

I'd start with a 10w30 and look at your oil pressure, hot at idle. If it's below 15-20, bump it up to a 10w40 or 15w50. Us a detergent oil as mentioned.

Redline is likely around 6200 with a hydraulic cam, 6500 with a mechanical.

Unless things have changed, Edelbrock's biggest carb is 750 cfm. That's to small for a 540. I agree that people think they look cool but you will need to go to a holley if you want to swap to one carb. I'd take a good look at the plugs if you think it's not running correctly.

Call the car what you want. :catfight:



Would this work as a solution? Also would I need a regulator since it is set at 7.5 lbs of pressure and not 7?

https://www.holley.com/products/fuel_systems/fuel_pumps_regulators_and_filters/fuel_pumps/carbureted_mechanical_pumps/parts/12-454-25


https://rspimages.holley.com/12-454-25.jpg?width=583

Vegas69
05-20-2015, 07:43 AM
Holley seems to think that it doesn't. I would put a NON LIQUID filled gauge on it to ensure you aren't getting to much pressure. Also, your supply line to the pump needs to be sufficient.

uxojerry
06-07-2015, 10:49 AM
Dart 325 heads would be a normal selection for a 540. With Lemon's headers and a 3.5 inch exhaust, Im thinking your 540 is something more, maybe Dart 345s. A run of the mill 540 is 650hp. A trick 540 is 850hp or so.

There aren't many BBC fans here. Remember you'll make more hp with a plug wire off, than most with a perfect tune, lol.

Xpock182
06-17-2015, 07:59 PM
Dart 325 heads would be a normal selection for a 540. With Lemon's headers and a 3.5 inch exhaust, Im thinking your 540 is something more, maybe Dart 345s. A run of the mill 540 is 650hp. A trick 540 is 850hp or so.

There aren't many BBC fans here. Remember you'll make more hp with a plug wire off, than most with a perfect tune, lol.



Could you tell me more about what you are referring to here? Also I am trying to figure out why the car is not cranking up immediately all of the time. It seems that after it sits for a week or so it won't crank.

I took the air filter off and try to crank it but I don't think it's getting gas. However if I pore a small amount of gas directly into the carburetor it cranks right up and runs fine.

I cleaned the fuel filter (it was a mess) cleaned the distributed cap & sprayed carburetor cleaner in both carbs.


Unfortunately the car does not have a fuel pressure gauge. This car sat for about 2 years before I purchased it.

Any advice? Is this a bad fuel pump?? Spark plugs?? Perhaps this car was not built for street gas??


Would love some help.

AMSOILGUY
06-17-2015, 09:08 PM
Could you tell me more about what you are referring to here? Also I am trying to figure out why the car is not cranking up immediately all of the time. It seems that after it sits for a week or so it won't crank.
When you say it won't crank do you mean the engine won't turn over or it just won't start and just cranks? Take your battery and have it tested. I keep a trickle charger on my car alot of the time and I bet alot of others do as well.

I took the air filter off and try to crank it but I don't think it's getting gas. However if I pore a small amount of gas directly into the carburetor it cranks right up and runs fine.
Pumping the gas peddle should accomplish the same thing i'm guessing you have done that?

What kind of gas are you pouring into the carb? Is it the same fuel thats in the tank?
I cleaned the fuel filter (it was a mess) cleaned the distributed cap & sprayed carburetor cleaner in both carbs.


Unfortunately the car does not have a fuel pressure gauge. This car sat for about 2 years before I purchased it.
Have a regulator and fuel pressure guage installed if you can't do it yourself.

Any advice? Is this a bad fuel pump?? Spark plugs?? Perhaps this car was not built for street gas??

Pull a fuel line and see if you have pressure. If you do then you need to make sure its the correct amount. Pull a plug and check the gap i'm thinking it should be around .035.



Would love some help.

Not a whole lot of help but this should be pretty easy to get figured out. Sounds to me its just a little cold blooded. Once you get it started does it not hard start after that until you let it sit again for a while?

Xpock182
06-18-2015, 05:13 AM
Not a whole lot of help but this should be pretty easy to get figured out. Sounds to me its just a little cold blooded. Once you get it started does it not hard start after that until you let it sit again for a while?


Yeah once its warmed up its starts immediately from that point forward. Idk if its just a cold start (its 94 degree's in Georgia) or if the carburetor is getting gummed up or if the fuel pump is going bad.


When you say it won't crank do you mean the engine won't turn over or it just won't start and just cranks? Take your battery and have it tested. I keep a trickle charger on my car alot of the time and I bet alot of others do as well.

The battery is good, I have a Volt Meter it reads about 14. Battery is a new Optima. The motor turns over perfect I just can't get it to fire as easy as I would like it to.


Pumping the gas peddle should accomplish the same thing i'm guessing you have done that?

Yeah If it doesnt crank up after a few seconds I heal the break and Toe the gas. Still doesn't seem to be getting any gas until after its cranked... then it runs just fine. And its the same gas from the tank that Im putting in the carb, 93 Pump gas.

Have a regulator and fuel pressure guage installed if you can't do it yourself.

I already have a regulator but not sure what the GPH is on it. I would assume 7-7.5. I need to get a fuel pressure gauge installed asap.

Pull a fuel line and see if you have pressure. If you do then you need to make sure its the correct amount. Pull a plug and check the gap i'm thinking it should be around .035.

Pulling a fuel line is a good idea, I'll try that today. As for the spark plugs I have been putting that off as they are a total pain in the ass to get to, but I probably need to do it.

Ron in SoCal
06-18-2015, 04:14 PM
So the motor runs fine when you do the ol' pour gas in the carb trick which means (to me) your fuel pump is probably fine cause it spins fast enough and moves enough fuel when the motor is running, but your lines or filter are crap when you turn it over via the starter.

Not sure if you've done this but figure out if the carb is getting fuel when cold. If not, have your flex lines tested and check / replace the filter.

I hate diagnosing over the interwebz.

intocarss
06-18-2015, 10:41 PM
Dart 325 heads would be a normal selection for a 540. With Lemon's headers and a 3.5 inch exhaust, Im thinking your 540 is something more, maybe Dart 345s. A run of the mill 540 is 650hp. A trick 540 is 850hp or so.

There aren't many BBC fans here. Remember you'll make more hp with a plug wire off, than most with a perfect tune, lol.

Could you tell me more about what you are referring to here? Also I am trying to figure out why the car is not cranking up immediately all of the time. It seems that after it sits for a week or so it won't crank.

I took the air filter off and try to crank it but I don't think it's getting gas. However if I pore a small amount of gas directly into the carburetor it cranks right up and runs fine.

I cleaned the fuel filter (it was a mess) cleaned the distributed cap & sprayed carburetor cleaner in both carbs.


Unfortunately the car does not have a fuel pressure gauge. This car sat for about 2 years before I purchased it.

Any advice? Is this a bad fuel pump?? Spark plugs?? Perhaps this car was not built for street gas??


Would love some help.What uxojerry is referring to is the port volume of the heads.... .

If that car has been sitting for a couple of years and is running rubber braided fuel hose, the rubber could be coming apart inside the hose and clogging things up.

Another thing I've seen when a car sits for a long while is the fuel pump diaphram gets weak as do accelerator pumps in the carbs and does not pump enough fuel when trying to start it via cranking it over...IMOHO get rid of the 2 carbs and get a single Holley or electronic EFI unit. BTW very nice car

Flash68
06-18-2015, 10:57 PM
What uxojerry is referring to is the size or flow numbers of the heads.... 325 cfm or 345 cfm.



Actually I think those are the intake runner volumes.... like AFR 227 vs 235, etc. etc.....

Those heads surely better flow a lot better than 325 or 345!

intocarss
06-18-2015, 11:34 PM
Actually I think those are the intake runner volumes.... like AFR 227 vs 235, etc. etc.....

Those heads surely better flow a lot better than 325 or 345! You're rt it's port volume :thankyou:

Xpock182
06-19-2015, 07:42 AM
What uxojerry is referring to is the port volume of the heads.... .

If that car has been sitting for a couple of years and is running rubber braided fuel hose, the rubber could be coming apart inside the hose and clogging things up.

Another thing I've seen when a car sits for a long while is the fuel pump diaphram gets weak as do accelerator pumps in the carbs and does not pump enough fuel when trying to start it via cranking it over...IMOHO get rid of the 2 carbs and get a single Holley or electronic EFI unit. BTW very nice car

I think you hit the nail on the head. I shined a light into the fuel tank and see a lot of black small bits in the fuel. I'm assuming its rubber.

With this being said I would have to assume that the fuel pump has some junk clogged in it also.

I think my solution is to replace the manifold (to accommodate a single 4 barrel Holley) and buy a new carb. Also I am going to consider replacing the fuel pump and all of the fuel lines.


And thank you very much by the way! :D

Now the question is if i should go ahead and go to EFI or replace all of these parts. :wacko:

68Cuda
06-19-2015, 08:11 PM
Now the question is if i should go ahead and go to EFI or replace all of these parts. :wacko:

If the money is not an issue, go EFI. You will have to swap out the whole fuel system though.

By the way, quite a few cars on this site do not have LS engines...

Solid LT1
06-19-2015, 10:24 PM
If the money is not an issue, go EFI. You will have to swap out the whole fuel system though.

By the way, quite a few cars on this site do not have LS engines...

I had one of those Weiand 440 Six Pack "super stock" manifolds back in the 70's on my Mopar, that thing had HORRIBLE! Fuel distribution problems, I nearly took a piston out with that thing....sold it for cheap...I hear they are worth some $$$ nowadays..

Back to OP, you want a billet mechanical fuel pump and do yourself a favor and make sure that big Rat motor has a lightweight fuel pump pushrod in it for high RPM reliability. The Carter AFB dual quads aren't known for being a good road race style carb, a single big Holley 4bbl carb will probably make more power and perform better in hard cornering. My buddy is building a touring 55 Chevy and he's using that dual quad intake with 2 FAST 4bbl throttle body/injectors on his 454 motor, he had a aluminum plate CNC'd to offset the throttle body's and make them fit the intake, it probably won't make as much power as a well done port fuel injection intake but, he wanted the 2X4bbl look on his motor. When the bill is all totaled up, I think he will have around $4K invested in his EFI project....about 1/2 the price of an all aluminum LS3 crate engine:lol:

When you replace the fuel lines go with PFTE or "Teflon" style hoses as they can tolerate the ethanol in modern pump gas. Earls, Fragola, Tech AFX are some good sources for PFTE style hose/fittings.

I'm looking closer at you engine photos....looks like you have a good billet mechanical pump on that Rat motor....rebuild kits can be sourced from Speedway Motors or CV products if you think then fuel pump diaphragm/check valves have problems.

uxojerry
06-20-2015, 09:46 AM
I think it would be important to get the current fueling issues fixed, carbs tuned etc., before going efi. You may find that you like the current set up.

I would suggest finding a local trustworthy engine shop. Have them fix your current issues and do a partial tear down on the motor and check everything out. That will get you the piston, head and cam specs and some peace of mind.

If you decide to go efi, check with F&B Throttle Bodies. They do a lot of 2x4 and 3x2 efi kits and are very reasonable.

The best BBC resource on the internet, is the performance section of the chevelle forum. A member near you may be willing to give you a hand.

Your car is beautiful and has some very nice parts and outstanding craftsmanship as depicted in the photos. Good luck working out the bugs.

Is that a Dart aluminum block? Photos kind of lead me in that direction. If so that is around $4k above an iron Big M.

68Cuda
06-20-2015, 03:43 PM
I had one of those Weiand 440 Six Pack "super stock" manifolds back in the 70's on my Mopar, that thing had HORRIBLE! Fuel distribution problems, I nearly took a piston out with that thing....sold it for cheap...I hear they are worth some $$$ nowadays.

Take a close look... no fuel distribution problems with this intake. This intake is considered the best cast manifold ever made for the 440. It takes some modifications and considerable tuning to get it to work good with the six pack carbs because the fuel tends to puddle under the center carb. It was originally intended for super stock use and was not meant to be used on a street car. Mine is converted to port EFI - no fuel mixture issues! Best of both worlds!

By the way, those intakes start around $1k these days, depending on condition.

If you decide to go efi, check with F&B Throttle Bodies. They do a lot of 2x4 and 3x2 efi kits and are very reasonable.

F&B did the six pack intake on my car (see my previous post for a picture).

GregWeld
06-20-2015, 06:11 PM
I think you hit the nail on the head. I shined a light into the fuel tank and see a lot of black small bits in the fuel. I'm assuming its rubber.

With this being said I would have to assume that the fuel pump has some junk clogged in it also.

I think my solution is to replace the manifold (to accommodate a single 4 barrel Holley) and buy a new carb. Also I am going to consider replacing the fuel pump and all of the fuel lines.


And thank you very much by the way! :D

Now the question is if i should go ahead and go to EFI or replace all of these parts. :wacko:





If you can actually SEE crap in the fuel tank - and after it sitting for two years it could be anything - moisture etc... and also the "new" fuels tend to not be so compatible with older rubber fuel lines and even the older rubber diaphragms in some fuel pumps. Several manufactures had issues with their good old METAL parts in carbs with the new fuels causing all manor of corrosion and stuff...

We don't know how old ANY of these parts are or their origins...

So --- if it was my car and I was having these issues and wanted to spend as little as I could - then I'd be removing and flushing the fuel tank... and replacing any of the "rubber" or flex lines with new - and make certain they are compatible with todays fuels (many people don't even know that you can buy different types of fuel line)... I'd replace or clean any filters.... I'd probably just go ahead and replace the fuel pump since you don't know what's inside of it... and I'd have the carb disassembled and inspected ------- or do as you have mentioned - replaced with a different manifold and a single carb. My guess is that you have a whole bunch of "fuel" related issues. The car should fire right off cold or otherwise with good fuel and properly tuned. That's not to say it will run or idle well "cold" -- that depends on the choke - etc if it even has one (doubtful).


RE: EFI conversion.

This would cost more... as you'd replace the tank with an in tank EFI electric fuel pump - it would require some wiring and relays etc.... you'd still want to replace any rubber hose in the fuel line... and you'd need to buy the type/style EFI intake and system that you'd wan to convert too. Then depending on whether or not you choose a "tunable" system - you'd have dyno and tuning expense... or choose a self tuning system - and skip that... but sounds like maybe you're the guy that would have all of this done at a shop. KaCHING....

The value would depend on how much you drive it - and whether or not you just want EFI. A carb or EFI are going to make the same power... The EFI is more tunable for certain things... and they generally start and run better "cold" or "hot"... but that, to me, is just nonsense if you don't drive the car that much... I have EFI on all my street rods... and a carb on the Mustang track car.... I can tell you that the Mustang lights off and runs within about half a revolution... and has no choke... so big deal - I feather the gas a little. It runs REALLY REALLY WELL... I have no intention of changing it over to EFI!

Depending on who's doing the work - the cleaning and changing a few hoses and the fuel pump - and inspecting or rebuilding the carbs - might be $2500 worth of labor and parts.... EFI is going to be 5 or 6 grand easily. Can be much more depending on what EFI you choose.... and then it's the "here we go, we might as well do....."


The main point is -- this bad boy should light off instantly.... Doesn't make any difference if it's a 540 -- or a 747.... a well tuned motor should fire with authority... if it doesn't - then you need to find out why. It's fuel / air / spark.... get 'em right or fight the fight.

Xpock182
06-25-2015, 08:30 AM
I really appreciate all the advice and help guys. This has helped me tremendously when deciding on where to go from here.

I have decided to take it to a local engine builder and have them do a full inspection with specific instructions to pay attention to the things that you all listed (Fuel Pump, Fuel lines, Fuel Filter, Spark Plugs, Accelerator pump, Entire fuel system, etc...)

Also these guys should be able to tell me a lot more about my motor and what it has. Fortunately they have a dyno so I will be sure to post pictures and results for you all.

Eventually we will find out what all this car has and get her running like she should be.


At this stage I am waiting for the results of their inspection then I plan on making the decision between a new Carb and mani or just pulling the trigger on EFI.


I plan on driving this car a lot, 2500 miles a year or more. So I want it to be enjoyable. Also I intend on moving to the interior once she is running smooth.

uxojerry
06-27-2015, 11:54 AM
If you can afford it, you should consider doing the efi while it is in the shop. I would also consider porting the heads and new intake while the engine is apart. My BBC 477 runs a ported 454r intake and is getting a FAST 2.0 XFI. You have a Beautiful Car!

Xpock182
06-28-2015, 05:24 PM
If you can afford it, you should consider doing the efi while it is in the shop. I would also consider porting the heads and new intake while the engine is apart. My BBC 477 runs a ported 454r intake and is getting a FAST 2.0 XFI. You have a Beautiful Car!



What makes you recommend Fast 2.0 XFI over some of the other systems out there such as the Holley EFI?

uxojerry
07-02-2015, 09:51 PM
My engine dyno'd best with a ported 454r intake manifold, and the 2.0 bolts directly like a carb. I mentioned head porting because Dart heads respond well to minor porting. If you port match a good intake manifold, you either have to have it tapped for multiport, or go with a 2.0. Most of the shelf multiport kits are not going to come with a particularly good intake. They are designed to fit under most hoods. You have a raised hood and clearance for just about any intake manifold. An Edlebrock Victor Jr is around $300, a Profiler Sniper Jr is $385. Porting of either is around $400. I mentioned these two as they are potentially good candidates for a 540.

Let's say you have a BBC 540 crate motor with 650hp. If you make a few tweaks, it can easily make 800. Port match the heads with a good intake, and get somebody like Chris Straub to do your cam and you are there. Yes hydraulic roller, smooth idle in traffic, etc. Top it off with efi and your set. Im getting jealous just thinking about it, lol.