Making the change: 2BBL to 4BBL

**MosportGreen66** · #1 01-03-2005, 06:19 AM

Whoa! Thanks guys!

The Holley carb on the Convertible is not correct for the car. I was thinking it would make a good candidate for the Camaro? The convertible is an L-79 327 ci, 350 hp car. What do you think?

-Dan

**Salvatore** · #2 01-03-2005, 06:55 AM

Put the Q-Jet on it. Simple and never fails. All linkage hooks up easier. JMO Sam

**Kurt S** · #3 01-03-2005, 10:06 AM

I disagree with y'all.
Everyone swaps 2bbl to 4bbl, but I doubt you'll see any performance gain. That 2bbl is more than keeping up with the engine.
I'd suggest rebuilding the distributor (vertical lash and advance tweaking) and tuning what you got.

Jeff H · #4 01-03-2005, 04:25 PM

If you're gonna change to a 4 bbl, do a cam swap as well. Otherwise the gains will be minimal like Kurt said. Even with another cam, the heads are probably limiting the potential with small valves. So do the cam, heads and 4 bbl. Or do nothing(it's cheaper). I would look at the ignition system as the best place to pick up some performance.

Pantera · #5 01-03-2005, 06:16 PM

Jeff I hate to disagree with the head statement but you are not going to pick up a great deal of noticable in the seat of the pants HP by changing the heads on a low compression street car. If you had the motor on a dyno it would be such a small gain that the cost would not warrant it. Heads only make a difference above 4,000 RPM.

In my opinion a good mild Hyd cam and a four barrel carb with the timing set up right, makes for a very drivable street machine with out spending a small fortune.

Pantera

**Salvatore** · #6 01-03-2005, 06:33 PM

Put the Q-jet and cast intake on. Have the distributor rebuilt and if everything else is where it should be and up to the correct tune up, the car will perform good with NO complications. Don't need to change cams, heads, headers, etc. Clean it up and paint the engine to look nice. Make it a one day project. Don't need to over engineer it.

indyjps · #7 01-03-2005, 07:26 PM

ive got a q jet off my original 69 307 car that maybe the numbers you need if going correct. its stored a state away but i could have it shipped over to you. pm if interested.

Supercar_Kid · #8 01-04-2005, 06:58 AM

[ QUOTE ]
Don't need to over engineer it.

[/ QUOTE ] You said it Sam.

**Kurt S** · #9 01-04-2005, 10:31 AM

[ QUOTE ]
Don't need to over engineer it.

[/ QUOTE ]
I too agree.
Try the simple route. Tune it (esp the dist) and get what it will give.
If not happy, run a baseline test (say 30-60 in second gear), then try your 4 bbl swap and compare.

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