What are your guys' reasons why Tuned Port Injection is better than Carburetors? Or, if you like carb better, put that then. My reasons for TPI is:

-better gas mileage
-the engine looks a hell of a lot cooler
-the computer control ensures a precise air/fuel mixture

What do you guys think? Thanks.

 

All of those plus:

-better emissions
-usually easy to diagnose problems
-easier and more accurate to tune using a scan tool and burning your own chips

Pro's for a carb:

-carbs and intakes much cheaper than fuel injection parts
-easier to tune for ol' timers

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Greg Westphal
'87 IROC 305TPI/A4

 

You will create a big argument with this topic.. 8^) I like both, but have no skills tuning a carb (never bothered to learn) and find fuel injection much more interesting. I think TPI is one of the most "classic" injections ever made, simple, clean, works very well, on most any small block chevy - look at many hot rods, I would bet at least 1 in 10 have TPI if it is a chevy sb.....

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1991 Camaro TPI, 355ci. Sportsman 11 heads, LT-4 Hot cam,Pete Jackson gear drive, on,and on, and on... 13.6 @ 102.5 with a 2:73 open rear, no traction, no tuning, no practice.

1985 California Edition IROC red, polished TPI and polished wheels, otherwise completely stock 305ci. & automatic trans.

1991 fullsize Blazer 4-wheel drive, 350,700r4, Pro Comp lift, K&N, TBI spacer, 3" Catco cat, 3" cat back Flowmaster, etc....

 

I have owned both on the same car and here is what I think:

1) having gotten into auto mechanics after the phase out of carburation, I know 100xs more about F/I than carbs.

2) I would have thought that my gas milage would increase after the TPI conversion, but actually went down thanks to injectors that are way to big, that and the fact that I "light 'em up" at every red light.

3) Just by swapping to TPI with light mods, I gained 1.2 sec in the 1/4. (16.1 > 14.9)

4) It looks way better than the hokey air cleaner, vacuum lines, etc... associated with carbs.

5) throttle response is impressive and tire spin is on demand (unlike the crappy Qjet)

Just my $.02. All in all, I would trade TPI for carb any day, and although it was a major undertaking to make many custom components look factory, I would do it again anyday.

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'87 Trans Am
S/D TPI retrofit including functional PassKey, 22# injectors,
JET AFPR, Ported Plenum,
TB Coolant Bypass,
SSM SFC, Boxed LCAs,
8mm Accel wires,
Flowmaster Exhaust,
16" GTA rims,
Corvette Servo,
KYB Shocks
-->14.97 @ 94.9 MPH<--

'97 Bonneville SSE

 

All of the reasons given above are very good. I would say that I like both and it REALLY depends on the application. For a street car, no doubts about it...fuel injection. The engine smoothness, good fuel economy, broad range of rpm operation and increased reliability are my hot buttons for FI. For an all out strip car, carb...within their intended narrow operating range, they still are the best HP/$ bang IMO.

 

Very good and honest answers in this post. I haven't seen one that I would want to disagree with. The Holley double pumper in my 69 works great when I'm blowing the doors off most of the competition, but I also love passing up a lot more gas stations driving my totally reliable fuel injected third gen!



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89RS w/350 TPI; 69RS/SS w/450 HP 350/Muncie 4-Speed "Too weird to live, too rare to die."

 

I forgot to mention the overall drivability. Idle and cruising is just so much smoother in my opinion.

 

That's not universially true.
Also, it ALL Depends on the tuning.

I've been into carbs heavy enough to be making my own parts for Webers for racing applications, and I can get a proper Weber setup to do everything just about as well as any EFI. The slight differences is fuel handling as you get to like 1.2Gs lateral accleration, the WET manifolds using a common plenum suffer slightly. AN IR will match and still exceed any EFI I've seen so far.
As far as a Holley, and a mechanical distributor, all things being equal, EFI would match the HP, but the drivibility goes to EFI.
There are things you can not do with a dist., that you can with EFI.

 

Well, in defense of carbs, they are cheaper to buy, easier to tune, and generally easier to trouble-shoot.

l can buy a Holley 600 for $200. Then l can buy a decent intake for say $125. Thats a COMPLETE fuel-air system for $325. Cant do that with EFI. Especially cant do that with TPI.

That said, EFI still does generally get better gas mileage, and generally better driveability.