Bought a used Holley Carb for Lisa’s car.

So Lisa (FieroChicks) Fiero has a lowly 305 and a Rochester Q-Jet on it. The Carb is hooped and needs some new parts to fix it.   We started searching for a Carb about a month ago. We found this one. It came from a running engine and then was put in storage.   It needs to be cleaned up and there is surface rust on one of the butterfly's. However everything seems to work smooth. We bought a rebuild kit for it with new jets and new gaskets.

Installing the Carb would only help about 1/2 of her problems, she has smogger heads from the 80's on the car, so we are going to find a set of late model vortec heads and matching intake. After talking to Blair, he said the 80's 305's had Horrid heads on them and the Q-Jet aka Quadra Junk did little to help the situation.   I was hoping for her to gain maybe 30-40hp with new good heads a good Carb. He said probably more like 100hp over what she has now.   Which is going to kinda suck, for me as she is then going to be able to make my 4.9 5spd look like I am standing still. LOL.

Well here are the pics of the Carb.

Can anyone give me any details on it. I know very little about carberated engines. Blair is going to help with the rebuild, but I would like to put together as much info as I can, just so I know whats going on and don't end up working blind.

I know how to work on engines, I can do a head job on a Fiero 2.8 without any problems. I can work on my fuel injected 4.9 caddy motor in my 85GT, however when it comes to SBC stuff, I just don't have any experience with it.   We will be putting all new vacume lines on it when we do the carb and intake swap. Probably get some "ricer" type vacume lines in red to match her car. Her current engine bay looks pretty ratty due to the age and way it was put together.   We did not build her V8, we bought it already done. We got the entire car for less money than what a V8 kit would cost from Archie alone.


Well it serves me right for not checking the packaging on the rebuild kit we bought! :(

We were at the Huge Portland Auto Swap meet while we were in Oregon. We found a guy selling carbs, we asked if he by chance had a rebuild kit for a Holley 600cfm carb. He asked a few questions and then handed us this and swapped the jets out of the package and gave us different ones.

I am just today took a close look at it and it says it is for 750cfm carbs. Frack, I don't think this is going to work for our carb. So we are out the 35 bucks we gave him for it.

Proper size jets make a huge difference in carbureted engines. Years (and years) ago I bought a ‘67 Chevelle SS396 for a rather low price because the rebuilt 396 just didn’t perform well at all. It would crap out something fierce at high RPM.

I took the brand new Holley carb apart and discovered the jets were way too small for a big block Chevy. (It had jetting for a late '70s "smog" engine.) I put in the appropriate size jets and holy smokes, the 396 came alive! 

I guess you must have a cat installed. Are you positive it's good?

What are the AirCare readings based on for this Fiero - the current V8 engine or the engine (V6?) that originally came in the car?

I looked this up at AirCare:

"A catalytic converter is necessary for all 1988 and newer vehicles to pass an AirCare inspection. Older vehicles may be able to pass inspection without a catalytic converter."

I guess that explains why you're allowed to take the car through the test without a cat. However, you may find it awfully difficult to actually pass the test without one when you're trying to get a carbureted V8 to squeak below fuel injected V6 limits.

Edited by Patrick

Carbs

'Insert smoke and mirrors here'

are great.

Well, they can be anyway. I have a Quadrajet (Junk, bog) on my 350 marine engine and it's good, after tuning it up. People junk them because they don't understand them.

They are like early fuel injection in that the have an idle circuit, a progression circuit with a 'power piston' which meters fuel based on need, then it has secondaries which open based on demand (Air requirements), not throttle position.  The bog in quadrabog comes from people setting up these secondaries too loose and the open before they should causing a bog. Incedentally, the new pricey Demons do the same thing now. The quads have to be kept clean so the popwer piston functions properly. Tuned, the same carb can handle a 175hp 305 and a 400 hp 350. Pretty Cool.


Anyway, your question is about a holley. I'm not really sure how they work in detail, but tuning will likely be required on the head change and you may as well do the cam too while you're at it? This will mean jetting changes. The best way to dial it in will still be a wideband 02 sensor, othwerwise you're stuck reading the plugs and set-of-pants/ping/detonationometer (Especially cause you're likely to be lean). I'm going to get a 02 wideband from Innovative eventually to tune the 3.4 (Setting up for turbo eventually)...It has a sensor, driver, readout and a 6 channel logger for $350. Not bad at all.



I have a bunch of info on the quad (Diagrams, exploded views, tuning info) if you want, otherwise good luck with the holley.

Chay

Truck passed - met all the current specs it needed too.
Car passed - just got lower numbers (yes, the same numbers!) than the truck.