I just bought a TPI motor with 355 Vette heads and I am wondering if there is anything special that I amgonna have to have to run a carb instead of the TPI setup.

 

mechanical fuel pump and new distributor. youll also have a lot of wires to be removed unless you want them just hanging everywhere . you also will need to remove the electric fuel pump thats inside the gas tank, and run new fuel lines to the mechanical fuel pump. while youre getting a new distributor, you might as well get new plugs and wires. you also have to do something to the tranny to allow the torque converter to function properly. might want to take it to a tranny place. you can drive it without doing anything to it, but it wont get too good of gas mileage. its a pretty big job, so make sure you know what youre getting into before you start.

 

may i ask why you are dumping the TPI setup for a carb?

 

I have had my TPI set up for years and I wouldnt trade it for anything. I think you would be money/time ahead to keep the fuel injection.

 

Resist the urge to go to the dark side. Injection is where it's at.

 

The TPI gets a bad wrap for it's lack luster High RPM performance......BUT.....You cannot beat the TORQUE and the Stoplight to Stoplight power you get taht comes with the TPI. I have the GM 350HO Crate w/TPI, and it pulls hard up to 5,000 RPM (cam and Vortech style intake helps out I guess)

KEEP THE TPI!!!!!

 

Take their advice and keep the TPI unless you wanna run like 10's easy.

 

My OPINION, I'd rather spend less to use a carb then havr to spend more on a TPI and have to work on that mess. TPI's are unreliable IMO, not much can go wrong with a carb. A properly tuned carb will get damn near as good fuel milage as a TPI setup too, but if you have a fast car, why does fuel consumption matter?

I'm ranting and I don't know why.

 

Hahahahaha Damn, you've been hanging out on the carb forums for too long. Come back to reality, ok?

 

Carbs aren't prone to vacuum leaks. Carbs don't top out at 4500rpm. It's a lot easier to take off a carb than a plenum and runners. You don't have to burn chips for a carb.

Not to say I don't like TPI....I think it's a great design if you're building for low-end torque in a daily-driven car. However, it does have it's disadvantages just like everything else.

It'd be nice to see a simple answer to this question instead of the mile-long debate that invariably pops up. He didn't ask if he should use TPI or carb, he asked what it takes to change from TPI to carb.
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Things you have to change on the TPI engine to make it work in a carb-equipped car.....intake manifold, distributor (you need a non-computer dist. unless you're using a CC Q-jet) and of course the carb itself. That's all it takes to make it a carbed engine....making a TPI car work with a carbed engine is a very different story.

 

I love carbs and prefer them in most instances except my vette, when you are pulling more than 1 g-force from a modded suspension in a vette a carb just won't keep up with the turns and stops because the fuel won't mix well in the carb bowl. TPI is better for that but as to what it takes to do the swap:
distributor, non computerized
intake
carb
switch for the lock up torque converter to work
different fuel pump or pressure regulator 10 psi for carb, 40+ psi for TPI
and a good seat to hold you in when that carb power kicks you back into your seat

 

oh yeah forgot the intake manifold.....and the seats

 

Why would you switch from tpi to carb? For the amount of money and time you'd spend going from tpi to carb you could modify the existing tpi system to more than suit you needs, without throwing gas mileage and driveability out the window, not to mention saving yourself a big hack-job.Carburetion is the least precise fuel metering system, but also enjoys the most familiarity among most enthusiasts, simply by virtue of having a 100-year history. Carburetion doesn't have any of the flow limitations, but also requires more maintenance and adjustment for peak efficiency. TPI is the more refined EFI system on 3rdgens, and generally produced the most torque and fuel efficiency of all the systems.TPI can be modded to produce reasonably high performance numbers. It's just harder to do and alot more expensive than carb.Carbs can get more power cheaply though but not that much cheaper.For TPIs larger runner tubes(ported SLP siamesed runners),edelbrock's TPI intake,larger throttle body(52mm-58mm) and larger injectors can do wonders for tpi.

btw...I don't know of many carb cars that can start right up and drive away at below freezing temps or that get good fuel economy.

 

I've never had a TPI car, but with all the trouble to just change the fuel pump, I'll keep my carb!! And yes, even with 142,000 miles on it, I can crank it at below freezing and take right off, and I get several more mpg that my 4.3 TBI S10 Blazer. It will also pull well past 5500 if you don't keep your eye on the tach. I may be old school, but you can keep your injection. I'd rather drive mine than troubleshoot problems!!

 

I like TPI and I like Carb, TPI is my daily driver, its great, 392 ft lbs of rear wheel torque available whenever i put my foot down. But I only have TPI cuz the car came with TPI n it's not my hotrod so I'm only doing the basics.

Carb however, is simple, if I wanna change something, 4 nuts n the carb comes off. If you want horsepower, you go carb, if you want torque, stay TPI. But like the man said, he's asking what he needs to do to switch to carb, his mind is made up and I'm not gonna tell him to keep the TPI cuz I'm a fan of good ol' carbs too.

Carb, Intake, Distributor, Fuel Pressure Regulator, Gaskets, Tools such as Torx Bits, Ratchet, Sockets, gasket scraper, something that makes alotta noise when u kick it - cuz ure gonna wanna kick somethin while takin off the TPI system n stuf like tires hurt n dont make noise, so kicking a metal bucket attached to a short rope tied to a tree is a good idea.... (kicking a bucket accross the street then having to run after it gets even more frustrating)... ok im done. Oh thirdgen.org has a tutorial on this by the way.