Carburetor replacement
- Thread starter mickn
- Start date
Chuffer
CCCUK Member
I had a 650 cfm Edelbrock Performer carb fitted a few months ago on my 1980 and never looked back ! Admitedly mine is not the original 350 L48 engine , its got a 1985 Camaro IROC - Z 305 cu in . instead with an Edelbrock Torker 2 inlet manifold . Edelbrock carbs are very good and easy to set up but you will need to check clearance under the hood if you have a stock inlet manifold .
Forrest Gump
CCCUK regional rep
That's just what I was typing Ross! Just looking at Holleys, they do have one that that is a spreadbore Rochester replacement.
www.holley.com
It looks expensive though. I reckon you could get a Holley or Edelbrock square bore carb and a new intake for similar money and get a performance benefit from the new intake over the stock spreadbore. (And shed 20lbs of weight).
Any other carbs will require fuel pipe and filter re plumbing and possibly throttle cable connection alterations too.
Holley 0-80555C 650 CFM Classic Holley Carburetor - Spreadbore Quadrajet™ Style
Do you like the tunability Holley's modular carbs, but need to simply replace a Q-jet? The spread bore bolt pattern of the 0-80555C lets you do just that. It has vacuum secondaries and electric choke, so it is useable on a wide variety of vehicles and its single fuel inlet that is in the...
Any other carbs will require fuel pipe and filter re plumbing and possibly throttle cable connection alterations too.
Oneball
CCCUK Member
A rebuilt Q-jet is a good option in my book. Probably the cheapest. Bolts straight on. No need to change linkage, worry about air cleaner height or how the choke is setup. And they’re actually quite a good carb. The spread bore means small primaries for economic mincing around town and larger secondaries for hooning.
Forrest Gump
CCCUK regional rep
What kind of running issues are you experiencing? There’s a saying 90% of carb issues are actually ignition issues!
I would throw in that air leaks are often the culprit.
I think personally the problem stems from a perished rubber fuel line from last xmas. I had the car mot'd the day before xmas eve and one of the advisories was the 's' shaped fuel line was starting to perish. I'm wondering if their touching of this disturbed the hose and caused small bits to get in the fuel, not blaming them as this would have happened at some point. When I drove the car home it was not running very well but I put it down to possibly being damp from being left outside after the mot. I used the car a couple of times over the xmas break but it wouldn't run properly, certainly not when cold. About a week later the 's' shaped rubber gave up and started leaking fuel on my garage floor, I ordered a new one and had it replaced. The person who replaced it for me has worked on the car before and he also changed the plugs and points. He rebuilt the carb once before when I had a problem and the car had run really well since. He has blown out the jets etc but is now thinking the same, there are possibly tiny bits of rubber in there somewhere. I have ordered a rebuild kit as this is the cheapest option at the moment.
Forrest Gump
CCCUK regional rep
The integrated fuel filter in the Rochester should stop debris getting into the carb though? Was that cleaned out after the hose was changed? Nevertheless a rebuild and clean out is worthwhile - We had a thread on here recently where a fragment of the carbs own gasket has broken off inside the carb, blocking the jets.
Daytona Vette
Well-known user
Have you got an inline one way fuel filter ? - The micro gauze element may be getting blocked, if you have, reverse blow the fuel out on to a white piece of paper to see what you get
The perished hoses are a consequence of age but accelerated by the ethanol in fuel, you may need to change all the rubber fuel hoses - Ethanol will also cause running problems, but not with cold running
Try to source Ethanol free fuel (some Esso fuels are Ethanol free)
The perished hoses are a consequence of age but accelerated by the ethanol in fuel, you may need to change all the rubber fuel hoses - Ethanol will also cause running problems, but not with cold running
Try to source Ethanol free fuel (some Esso fuels are Ethanol free)
Roscobbc
Moderator
Esso Supreme 99 Super Unleaded. On the subject of Ethanol eroding rubber and some organic metals remember that the mechanical fuel pump utilises will use rubber and perishable components - worth checking-out or simply replacing as part of long term preventative maintenance. All current replacement fuel system components should be from materials that are less effected by Ethanol........can't say the same for Chinese and other third world generic replacements though.....