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Don't swap in a modern engine or efi for driveability

Michael_

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I often read or see people saying that modern engines (ls, gen3 hemi etc.) or retrofitting efi gives them so much better (daily) driveability
and use this as a reason for the swap.

I really can't understand this. I've been daily driving old fashioned carbureted cars (even with manual operated carb choke) since i started driving
and no matter if short distance city driving or long distance trips, i absolutely NEVER had an issue of any kind with them.

I also drove a modern 2017 challenger hellcat and i can't really see an improvement in driveability with the modern drivetrain.

I mean is it that hard to pump the throttle a few times before starting when the car has been sitting for a while?
Or to pull the choke by hand if its a manually operated choke? I dont think so.
For the bit of hassle you save, you add a ton of complex electronics on top that are no fun to work on with a new engine.

And again, i just completed a nearly 600 miles trip with my 72 cutlass supreme (that still has it's original 350 olds rocket)...

cover.JPG


Every fool could replicate that!

So my advice when it comes to swapping in a modern drivetrain or efi for improved driveability is: dont do it. :D
Of course other people might have a different opinion but in mine its just a waste of time and money AND makes things unnecessarily complex.
 
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Level of agreement: 100%

A properly tuned carb with a fully functioning automatic choke, exhaust manifold flapper, and points distributor will function fine.

The only argument against it is that todays gas evaporates quicker and needs a few extra cranks to fill the bowl back up after sitting for a few days.

Not a big deal for me.
 
Yep my buddy did a trip last year in his 1963 corvette 1700 miles and he is 71. He has always told me these cars were made to go across the US all day long.
 
I often read or see people saying that modern engines (ls, gen3 hemi etc.) or retrofitting efi gives them so much better (daily) driveability
and use this as a reason for the swap.

I really can't understand this. I've been daily driving old fashioned carbureted cars (even with manual operated carb choke) since i started driving
and no matter if short distance city driving or long distance trips, i absolutely NEVER had an issue of any kind with them.

I also drove a modern 2017 challenger hellcat and i can't really see an improvement in driveability with the modern drivetrain.

I mean is it that hard to pump the throttle a few times before starting when the car has been sitting for a while?
Or to pull the choke by hand if its a manually operated choke? I dont think so.
For the bit of hassle you save, you add a ton of complex electronics on top that are no fun to work on with a new engine.

And again, i just completed a nearly 600 miles trip with my 72 cutlass supreme (that still has it's original 350 olds rocket)...

View attachment 1140158

Every fool could replicate that!

So my advice when it comes to swapping in a modern drivetrain or efi for improved driveability is: dont do it. :D
Of course other people might have a different opinion but in mine its just a waste of time and money AND makes things unnecessarily complex.
Most that are doing the swap to modern drivetrains are looking for better efficiency or better drivability at high power outputs, if your going to tell me you can do better on either of those fronts with an old school motor your only kidding yourself. People aren't doing these swaps to get 10mpg or to have a 700hp motor that won't make any vacuum.

Have you driven a Hellcat yet? I have and it's almost disgusting how smooth they are yet they'll destroy my Charger with a healthy BB. I went from a 727 automatic to a Viper 6 speed and instantly doubled the miles I drove it per year and now get 19 mpg... that's just a transmission.

So yes, if someone is doing a modern drivetrain swap to get the same crappy fuel mileage and the same horsepower output as the OE I agree.. it's a waste of time.
 
Like anything, there are pros and cons. I agree 100% with @747mopar .

For example, when I drove my 70 Road Runner across country in 2015 I did it with fuel injection and computer controlled timing. I don't know that it would have run well at sea level and also at the top of Pike's Peak at 14,000 feet with a carb.

Having said that, I agree that people who believe these old carbureted cars will break down after only a few miles are fooling themselves. A well tuned carbureted car can run really well, and handle long drives without breaking a sweat.

So it really comes down to what you want...
 
As some of you may know I just recently pulled a 4.8 LS out of a 68 Cutlass 442 clone to swap it for a Corvette all Aluminum 5.7. The swap was already done I just replaced what he already had. But in the process gained a few parts. Like a 1968 Cutlass 4 core radiator a Quick Fuel 750 carb. He wanted to go EFI so I slapped a Sniper kit on it. The car ran decent but was not through the learning stage. I told him he needed to drive it so the Sniper would learn. Its been 2 weeks since I completed it and he was ecstatic about the amount of power compared to the 4.8. This was the only modern engine I have swapped over.

But on the reliability of a carbed car only depends on the owners ability to keep it tuned. Not everyone is mechanically inclined and to them EFI is easier to deal with. I think its more of a want than a need. The thought process is that it will run and drive like a modern car they can just get in it and drive across the country. And some people just get sick of replacing the same old damn parts that always break. Take the damn Orange ECU for instance. Only lasted 2 years. Does everyone carry a second ECU with them? Modern times people want ease of use. THey would have blown a brain gasket if they had to live through the 60's and 70's. 100k on a car was a death sentence. If they made it that far. Look at the Odometer in your classic ride. Most are well below 100k because at some point they became unreliable.

And by the way. The OP picture looks like it could have been taken in 1977 lol
 
Is it possible to get your carbed engine to idle smoothly at an efficient air fuel ratio like 13.5:1? And, have it cruise efficiently at an efficient a/f ratio of around 15:1? And, have it run wide open at a an optimal a/f ratio of 12.5:1? And, have it optimize the ignition timing to take engine load and throttle position in to account to nail the most optimal ignition timing for the engine? And, do all that with a smooth transition from idle to cruise to wot, with no bogs, flat spots, or hesitation?

The answer is sure you can. But at what cost? Carb tuning is no easy task. Creating the most efficient timing curve is not a simple procedure. Paying some one to do this for you won't be cheap.

EFI can do all of this with some easy to do key strokes or on a hand held controller. If you have to pay someone to do it for you it wont be cheap either.

The next question is, why do any of that when the car runs great the way it is.
 
Zero plans to modernize anything. Contact points, carburetor, drum brakes and all that are part of owning an antique hot rod.
 
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Zero plans to modernize anything. Contact points, carburetor, drum brakes and all that are part of owning an antique hot rod.
Agreed, except maybe for the drum brakes. A buddy has a high horsepower 55 Chevy which wouldn’t stop for beans. He converted the front to disc. Problem solved. Of course that’s a Chevy so all bets are off.
I did just convert my ‘66 Belvedere to front disc. Won’t be able to get it out on the highway until next year so I’m interested in seeing if the money was well spent.
 
@Jerry Hall He has several Modern Hemi Swapped cars I guess you could ask him how reliable they are. On the same note. Back in the day when cams were made in the USA you could go along time with a cam that along with leaded gas. Modern gas and oil vs the old school stuff makes the old cars with flat tappet cams, just that old. Unless you purchase zinc additives, the modern cams are roller cams and they fail probably just as much but for other reasons. I guess one isn't any more reliable than the other. The way you take care of it is the deciding factor. All of them have their flaws.
 
Adding to what some of the others said and BeepBeepRR....one of the big differences in the old vs 'newer' is I don't have to tune on the newer junk like I did on the older junk however, tuning was part of the fun. The down side to the new stuff is when things go wrong and you can't find what the problem is. All the sensors and the dang computer acting out and the scan tool isn't helping and on and on. Screw that mess.

As for brakes....disc is good on the front but drums on the rear do just fine and OD transmissions is another huge plus. You can also stick in a roller cam into the old stuff and truck on.....and I'm not afraid of tuning on a carb. On the highway if you have a steady foot, even a DP Holley can (and has) delivered great fuel economy for me but they are horrible in town but a TQ on a 340 powered 71 Cuda did 17 in town without trying to get it but never did do a mileage run out on the highway with it.

Imo, it just boils down to what people like. Me, I don't care for all this new tech mess that costs a lot to buy and sometimes is a rpita to maintain especially when things go wrong. My daughters PT Turbo GT was one 'Pitiful Thing' when it wasn't acting right. Heck, even the aftermarket EFI can be a royal headache.
 
I feel the computer , injection , controlled engines have left me in the dust.
A late model that will not fire or dies on the road. Well...... I need someone 30 years younger to tell me why it's dead ,outside of a battery ect.
My 67 , as long as a rod is not sticking out of the pan I can prob get it running.:D
 
I feel the computer , injection , controlled engines have left me in the dust.
A late model that will not fire or dies on the road. Well...... I need someone 30 years younger to tell me why it's dead ,outside of a battery ect.
My 67 , as long as a rod is not sticking out of the pan I can prob get it running.:D
I understand them for the most part.....but yeah, trying to find what's wrong on the side of the road isn't something I want to deal with. Bad enough working on an older car on the side of a busy road let alone trying to trouble shoot a newer one on the side of a busy road.
 
I put an older used Edelbrock E Street EFI on my 73 a couple of years ago. Just removed it and put a used Edelbrock 650 carb back on. The electric fuel pump was going out. I learned a great deal by doing that install and playing with the tune. Good economy and good performance were easily attained by just changing values through the handheld controller. Much easier than jets, air bleeds, transition slots, power valves, and all that trial and error.

If you like to tinker, install an EFI and play around with it, they actually are very good. But, they are no different than dialing in a carb for maximum performance. It is just leaps and bounds easier with EFI.
 
Adding to what some of the others said and BeepBeepRR....one of the big differences in the old vs 'newer' is I don't have to tune on the newer junk like I did on the older junk however, tuning was part of the fun. The down side to the new stuff is when things go wrong and you can't find what the problem is. All the sensors and the dang computer acting out and the scan tool isn't helping and on and on. Screw that mess.

As for brakes....disc is good on the front but drums on the rear do just fine and OD transmissions is another huge plus. You can also stick in a roller cam into the old stuff and truck on.....and I'm not afraid of tuning on a carb. On the highway if you have a steady foot, even a DP Holley can (and has) delivered great fuel economy for me but they are horrible in town but a TQ on a 340 powered 71 Cuda did 17 in town without trying to get it but never did do a mileage run out on the highway with it.

Imo, it just boils down to what people like. Me, I don't care for all this new tech mess that costs a lot to buy and sometimes is a rpita to maintain especially when things go wrong. My daughters PT Turbo GT was one 'Pitiful Thing' when it wasn't acting right. Heck, even the aftermarket EFI can be a royal headache.
I almost 100% agree, you can't argue today's efficiency or reliability (in most cases) but I still prefer to work on mine with actual tools not computers. Where I disagree is driving in town with a Holley DP, mines technically not a Holley but same difference (Quickfuel) and it works seamlessly everywhere. Typically poor performance in town comes from having an oversized carb which many do.. bigger is better nah. This is what I'm getting 19mpg with too.
 
1 pump to set the choke and squirt a little for my 73.

99% success rate.

Disk on the front and rear drums are fine (note some new cars still made this way).

I'd be on board with an easy O/D swap/add, though.
 
I like my old cars old. Sure the new stuff is good too. I am tired of orange boxes that fail, chrome boxes that fail, MSDs that fail and Fitechs that have to be sent back though. Oh and I've been without a radio/screen in my 18 Ram 5 weeks so far after Fiat/Peugot/whoever updated and killed it. No sign when they are going to send me a new one, imagine how fun that will be when this modern stuff is 20 years old.
Want to pull the most beautiful dash ever put in a car out of your 68-70 Charger and "update" it with new stuff? Fine, just don't expect me to want to look at it. New engines are ugly as f+(& too, I won't be looking at those either and give me torsion bars every time.
But that's how I enjoy these cars and other people enjoy their cars in their own way too. Don't build your car for someone else. I have installed injection in old cars and probably will inject my next one. If I want OD though I can either use a manual A833 or in the case of an automatic use a 2.94 or 2.76 suregrip and build a 500 inch engine that will work with it and a 727, it isn't that hard.
 
I think I would like to try injection like sniper on my belvedere engine. I agree with runcharger in that newer engines look kinda ***. I like the look of chrome and black finned valve covers etc.

My carbureted car starts and runs fine but I have to admit that it would be nice to come home from a night of street racing and hanging with the boys without smelling like gas and fumes, to the point where I have to go shower or my wife won’t let me in bed. Lol

A huge negative of a carb for me is the bleed back and evaporation of fuel if it sits more than 5 or 6 days and all the damn cranking or a manual prime required to get it going. That’s part sucks sheet…

This baby with EFI would be the bomb!
088A6808-07D9-4974-81B7-F06F9BE1A3AD.jpeg
 
Im in the middle of installing the Hyper Spark addition to the Sniper. Its up and running I just need to dress the wiring up a bit. Had to do a few things prior to initial fire up. Update the firmware,and sniper software. Then punch in the engine parameters.. 8cyl,383ci,hyperspark ignition, wot timing and whether or not I'm using a power adder. Restart the Sniper and it fired right up. Then it takes a few minutes to get it to maintain an idle. But the more you drive the better it learns. That and with the ability for the sniper to also tune the ignition should be even better. This picture was taken when I installed the new cam.

HUAK6783.JPG


This was the night I was installing the hyper spark lol. Storm came in and I had to tuck tail and abandon the project.
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