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2bbl to 4bbl

Posted: January 30, 2016, 1:12 pm
by 1965 stepside
I have a 65 with a 68 302. the 302 was a 2bbl but I put an elderbrock 4bbl intake and carb on it. a friend who mostly works on Chevy's said I should put a cam in my motor because it burn up since I went from 2 to 4bbl, I personally have not heard that before but he is older and has worked on cars longer so I do value is advice. I am just curious if any had heard that before and if so should I put a cam in or will I be ok? I am not building a racecar just a cruiser nothing fancy at all.

Re: 2bbl to 4bbl

Posted: January 30, 2016, 4:06 pm
by slick4x4
he is either senile or pulling your leg.....

does it run ok ?.....

Re: 2bbl to 4bbl

Posted: January 30, 2016, 6:30 pm
by jkimbrel65
slick4x4 wrote:he is either senile or pulling your leg.....

does it run ok ?.....
X2

Mike

Re: 2bbl to 4bbl

Posted: January 30, 2016, 6:42 pm
by longcabjohn
I would get a new friend.



Johnny

Re: 2bbl to 4bbl

Posted: January 30, 2016, 7:32 pm
by 1965 stepside
it does run fine. he is a good friend coworker but a chevy lover so I take it with a grain of salt.

Re: 2bbl to 4bbl

Posted: January 31, 2016, 10:44 am
by skidoorulz
It is not going to burn up. it will run on 2bbls 90% of the time and unless it is a mechanical secondary carb will seldom open the back 2 because you say you are building a cruiser. You do however need to make sure your jetting is correct so you don't have a lean issue or a rich issue. Running lean could cause engine damage but you have to be darn lean. You would know it if it was

Re: 2bbl to 4bbl

Posted: January 31, 2016, 2:51 pm
by orangeRcode
289/302 have been run with 2 and 4 barrel carbs for years without changing cams. Only difference I'm aware of on mustang C code and A code 289s was the intake and carb.

I'm going from a 2 to 4 barrel on my 352 this spring. Going to add an aluminum intake and headers with the new carb. Still undecided if I want to swap out the cam and lifters. Will likely just run whats in there for a bit.

Re: 2bbl to 4bbl

Posted: January 31, 2016, 9:25 pm
by 1965 stepside
thanks everyone that makes me feel better. I am on a budget and can not afford to do a bunch of changes.

Re: 2bbl to 4bbl

Posted: February 1, 2016, 12:43 am
by Truckrat
Haha, that friend of yours is pulling your leg.
They love to needle Ford guys.
Just don't try to go too big on the carb.
Could probably get by good on a 500 cfm with
vacuum secondaries. Made for 300 cubes or smaller. TR

Re: 2bbl to 4bbl

Posted: February 1, 2016, 11:41 am
by Johnny Canuck
He is twisting your nipple. Dang Chebby guys and their heated tailgates,, what do they know anyway besides how to tweak on us Ford lovers, eh? Like Orange says, Small block fords have factory setups for 2 and 4 barrel intakes, not one thing different about the cams. FE motors the same, especially 360/390s. Ask mr Shebby genius if they change the cam from a 2 barrel 283 to a 4 barrel one. Watch him squirm then.

Re: 2bbl to 4bbl

Posted: February 1, 2016, 5:48 pm
by BAMAFORD
Just my 2 cents for orangeRcode, I went from 2 to 4 barrel carb and a cam change in my 352. I put in a dual energy cam from Competition Cams, I do not remember the lift or duration specs but after installing the cam, the push rods would no longer fit properly. As you know, the majority of FE engines have non-adjustable rockers. I tried shims and what ever else i could think of but with no luck. So I happened upon a set of adjustable rockers for an FE on Ebay (these are hard to find) so I grabbed them up and low and behold I could now get the proper adjustment with the new cam. Moral of the story - don't put a high lift cam in an FE. :lol:

Re: 2bbl to 4bbl

Posted: February 1, 2016, 10:36 pm
by 1965 stepside
thanks every one. right now I have a elderbrock I think it is a 600 cfm that should be ok correct?

Re: 2bbl to 4bbl

Posted: February 2, 2016, 11:36 pm
by chris401
Your friend was probably repeating the old saying I have heard. "A Sunday driver and grocery getter won't last long driven hard and a car driven hard won't last putting around town." Has to do with how low revers wear and oil deposits build up vs the wear on an engine that is run hard.

Re: 2bbl to 4bbl

Posted: February 3, 2016, 8:46 am
by 64 f100
The only way switching to a four barrel carb will burn up your motor is if the two main barrels cause it to run extremely lean. Generally speaking the four barrel main two will be smaller than a two barrel. Quite often this will increase fuel mileage as long as you stay out of the other two barrels. However, I forsee no problems with what you are doing. If running to lean then a set of jets will fix the problem.

Rich

Re: 2bbl to 4bbl

Posted: February 10, 2016, 8:48 pm
by 66camperspecial
My 65 galaxie has a 70 302 that was originally a 2 bbl motor and got a 4 bbl about 10 years ago and ran fine for those 10 years until I burnt a exhaust valve in december,I blame Jegs for that since they sent me intake gaskets that were made for heads with larger intake ports that ended up not sealing too good and causing the motor to run lean that also took out all the intake valves and guides that took about 10 years and 32,000 miles to do the damage. From now on I will check the gaskets more closely and do not let this scare you as if you do it right with the right parts it should run good for many years.