i have a 350 rocket from a 70 convert in my 70 supreme, as far as i know, it has less then 20000 miles on it, heres then thing, carb is beyond bad......i know nothing avbout carbs, so a rebuild is out of the question, a friend of mine offered to give an aluminum intake and a elsebrook four barrel. am i in danger of snapping rings or other castrophes with this swap, ive heard many horror stories about this.

 

super simple, unbolt the carb and anything attached to it, throw it out. Unbolt all the bolts that run into your intake ONLY. pop the intake off. clean all your mating surfaces, and glue the new intake on. Before you do this, make sure to drain some of your coolant, otherwise antifreeze will end up in your oil. Just be careful and take your time. It would be wise to find a chilton, it will give you the proper torque specs, and pattern, however someone on here can probably tell you too. LOL

 

i knew, how to do it, i have been told all the extra power after 40 yrs of a 2 barrel can wreck havor on my motor

 

Im not gonna say thats not true, but I have never heard that anywhere, as a matter of fact intake and manifold swaps are very popular, i have done numerous, never had any problems. Your not doing anything but allowing your engine to intake fuel and air more efficiently.

 

I would not worry about it. Put it on.

 

I'm not going to say it either. Instead, I'll say "what a load of BS". Swap the intake, you'll be fine. Of course, the qualifier is the old "when driven the same". Don't put on the 4bbl and start doing 8,000 RPM holeshots. That WILL break something (which, I suspect, is how these wive's tails get started). Also, be sure the new carb is jetted correctly for your motor. Too lean a mixture and you will break something.

 

well put Joe --just about sums it up I would have thought

 

thanks for the helpful advice. now just one more question is a performer 850 cfm too much for my 350?, it seems about right to me. it was on a 454 before beeing benched for a dual set up

 

I'd say 850 is overkill and your motor will probably run too hot.
I'd go 600cfm.

 

Don't think they even made a 850 unless to are talking about a Qjet they made a few years. If thats what it is you should be OK but a smaller carb would be a little better.

 

Sounds like you subscribe to the philosophy of "if some is good, more is better and too much is just about right."

Let's get serious here. A 350 cubic inch engine with 100% volumetric efficiency (which is optimistic) will flow just a hair over 600 CFM at 6,000 RPM.

Yeah, I'd say an 850 is too much. Keep in mind that GM tuned the Qjet to a wide variety of displacements by using the tiny primary bores for good low-end response and tailoring the air valve opening rate and angle to match the engine's requirements. I doubt your perfomer 850 will be able to do that.

 

i dont really subscribe to the more is better, im more of a free is pretty good kinda guy. ill look for a 500 or 600 , someone has to have laying around up here somewhere, plenty of donor fords quietly rusting away

 

If you already have that 850 cfm carburetor maybe you could sell it or trade it for a nice Quadrajet. I really am sold on those, of the same opinion as the others.

 

You never said...Is it already a quadrajet? Thats the only way you have an Edelbrock 850

800 is the biggest they ever made a square bore carb
http://www.edelbrock.com/automotive_...erformer.shtml

In the 90's they bought the tooling from Q-jet and were selling them new with a few choices in CFM

 

like i said, i know less then nothing about carbs, im pretty sure he said eldebrook 850, but obviously it is not, either way i think ill pick up a smaller one. there a prefered carb with electric vs cable choke? the choke has never worked on this car and it will always start so i never really gave it much thought

 

Edelbrock sells both rebadged Carter AFBs and rebuilt Qjets under their name.

 

Go look at it. Edelbrock made too different types of carbs. The ones like I posted above is the common Carter AFB type carb they have been making for 20 years and still make. For about 4-5 years in the 90's they were making Quadrajets with the Edelbroke name and did make an 850. If thats what he has it will work for you or will be good trade material if you can get it cheap.

To tell if it is look underneath the carb. If you have two very small barrels and two giant ones you have a Q-jet. If they look the same on all 4 then it is a AFB type. Get the number stamped on it and someone here can tell you what the CFM is. Maybe you will be lucky and its a 1405 or 1406 which is 600 cfm with and without electric choke.

 

well, my intake showed up, it most definatly is not for an olds 350 to narrow, but its wider then a chebbys intake would be... maybe a ford or a pontiac?
neways i guess ill get one on e bay, but has anybody here ran a demon carb? been told they are pretty reliable and cheap

 

Post a pic of the intake and someone can at least tell you what it is

My and other friends experience with Demons is they are junk.

 

i kinda was thinkin that, the old adage" you get what you pay for"

 

My combo is an Edelbrock Performer manifold with a Holley 600 square bore with a manual choke. It suits me fine, but thats my opinion. Some of the guys on this board use Holleys for doorstops..., I myself, don't have alot of Q'jet knowledge, but with the price of gas, I'm becoming kinda quadracurious.. LOL.

 

so someone tell me whats the difference between the a regular carb and a q jet

 

AND HERE IS THE WEBSITE THAT I HAVE BEEN LOOKING AT FOR A CARB SWAP

http://www.carburetorsandmore.com/index.htm

 

Quadrajet is the brand name of the four barrel carb that GM used from the mid 1960s through 1990. The question you should be asking is "What is the difference between a square bore and spread bore carb?"

Four barrel carbs for the most part come in two flavors, square bore and spread bore. The square bore uses four barrels that are about the same diameter. The spread bore uses tiny primary bores for good atomization and gas mileage and two huge secondary bores for power. Most aftermarket four barrel carbs are square bore. The Qjet is a spread bore. That's why the intake manifolds are different.