Shaunbo13

Hello everyone. I have a 1968 Olds cutlass holiday coupe 4 door..original stock 350 rocket with a 2bbl. I dont get a whole lot of take off power, but it does get up and run. I was thinking about the 2711 edl intake with the 600 cfm edl carb.. would it make a diff with power or would i just be wasting my time?

oldcutlass

I would use the same manifold but run a quadrajet. Don't get me wrong the Edelbrock carbs are ok, but the Rochester just sounds and performs a little better. Power wise, you won't notice a big difference. Do you have dual exhaust on your car?

lshlsh2

What rear is in your car? I bet it is a 2.xx something. A better rear end will wake it up.

Larry

Shaunbo13

I dont know what the rear is...whatever is stock...i was under the impression that i have to change the intake to make it a four barrel...but i dont know...edl said a quadrajet wont go on my car..I have duel exhaust with headers..let me know more about the quadrajet

oldcutlass

The 2711 will accept both a square bore and a spread bore carb with no adapter. You'll have to run an electric choke with either carb. You'll also have to mod your throttle linkage to ensure the carb opens up all the way, not a big deal.

Also if you bump your timing up a bit it will help getting the most power out of what you have.

brown7373

oldcutlass, what do you mean you have to modify the linkage? Is that only for that manifold? I ask because my stock manifold and Q-jet won't open all the way. A new cable and straightening a bent rear bracket helped, but it still is a little short of full open. I even removed some p-adding from under the carpet beneath the pedal.

jag1886

If you want to save some money I've twice converted the stock 2BBl to a Holley 500 2BBl, they make a straight bolt on adapter plate to do this, throttle bores on the Holley are the same as the old Roch, it's quick and easy to do and makes a large improvement in performance.

oldcutlass

You always have to perform some mods when changing from 2 to 4 barrel or from 1 brand to the next. Without seeing what you have it's hard to give an opinion, however I will tell you if the carb is not opening all the way you are not getting all the power out of it.

You just have to tinker with it.

M-14

I'd look into doing a Th2004r trans swap, I'm thinking you've got a 2spd jetaway. Its not a hard swap.

brown7373

My carb and intake are all original to the car, but when I first got the car, it wouldn't open enough to even open the primaries all the way. I think my problem started when a previous owner repaired the broken thm350 cable, thus making it slightly shorter. I think he bent the bracket on the rear of the carb so the accelerator would not idle too fast.

MDchanic

I agree with the above: with a 2.56 or 2.73 rear and a Jetaway, you're not going to be fast off the line no matter what you do.

- Eric

oldcutlass

Is the trans cable on the carb or the gas pedal? The thing about old cars is you get to inherit the previous owners good or bad repairs. You will have to get in there and redo/undo some of the srewups that have been done. Not a big deal.

How mechanically inclined are you? Do you have a chassis manual, if not get one. They are good reading in the library during morning constitutions and very helpful for repairs. I like Motors Manuals also, between the 2 you can figure almost anything out.

After you get your linkage fixed and decide whether to change manifold and carb, the next thing you need to do to make sure your not leaving power on the table is a good performance tune up with quality parts.

Shaunbo13

Thinks for the info guys! I am pretty sure my rear end is a 3.08 and i have a two speed jetaway....was thinking of going to the edl carb...but nobody really answered my question...is it going to make any kind of difference?

oldcutlass

I did!

Shaunbo13

you did what? Notice a big difference, or you swapped a 2bbl for a 4bbl? What did you do?

oldcutlass

I answered your question about noticing a big difference by changing from 2 to a 4 barrel, the answer is no, not a big difference.

Shaunbo13

Well, Im going to go out on a limb here. You told me to use the same manifold and run a quadrajet. So if you have a two hole manifold and a four hole carb...youre still running on two. I wouldnt notice any difference either. Just saying.

MDchanic

He meant, use the same 2711 manifold, not use the same 2bbl manifold

- Eric

oldcutlass

This is exactly what I was saying, but instead of using an Edelbrock carb I would use a Rochester.

Shaunbo13

oh, lol...ok. Im sorry I misunderstood. So if Im not going to notice a difference in power whats the point in doing it?

oldcutlass

Did you get your linkage to open the carb all the way @ full throttle? That will help a lot. Advancing your timing a bit will help also.

Shaunbo13

are you reffering to the gentleman that mentioned that or me? Anyways Im new at this kind of stuff, at full throttle do you mean all the way to the floor, or at a certain rpm? and how do you advanced your timing? I would figure a car like this, if i floor it at a stopsign it should squeal the tires a little...just a slight hesitation and just takes off...other than that it sounds and runs great!

olds 307 and 403

If you want a new carb, get the new Street Demon 625 cfm. You gain mileage over the Edelbrock and equal power. It is based off the Thermoquad but new castings with the Thermoquad's issues fixed. The Thermoquad was very similar to the Qjet but had a
Bakelite "plastic" main body. You can get an aerospace polymer or aluminum main body on the new Street Demon.

Shaunbo13

I'm going to run this edl 600 cfm gotta good deal on it. If it doesnt perform well then i will go with the quad....after i get this figured out with linkage and all off to the rear end. I got the heads milled new gaskets and new valve covers, looking pretty good. Thanks guys, I will keep you guys posted on the progress!

76olds

I run an edl 600... With the performer I myself didn't notice a difference when I removed my stock intake and quad.... just a lot of weight off the old bomb... However that's just me, I just liked the look of the all edl, package at the time. Sounds like your making progress keep us posted and pics would be great.
Eric

Shaunbo13

Hey bud, I didn't remove the quad...I removed the original 2 bbl, is that what youre talking about?

76olds

Did you post you were going to run your edl 600 as you got a deal on it ??? So I guess you decided to run with your Rochester quad then.

Shaunbo13

Someone mentioned that the quad was going to perform alot better thn the edelbrock. I took the old intake and original 2 bbl off and replacing it with 2711 edl intake and the 600 edl carb. thx buddy. What do you think edl or quad?

oldcutlass

So how does it run now?

1964f-85

Change the cam and springs when you make the change. Go mild cam!!!
I had a 72 cutlass 2bbl that a changed out to a 4bbl quadrejet, it made alot of noise and ran slightly better, but it needed a better cam to make use of the extra fuel. Cams are cheap, get the Edelbrock cam package, it not to expensive. Change the timing chain and water pump while your in there.

Fun71

Yep. If it were me, the next mod after the 4bbl would be a trans swap. TH350 if keeping the rear gears (another gear plus lower first gear); some type of OD if changing to lower rear end gears is in the plan.

Shaunbo13

Im dragging my feet. I bought a 3711, to try and save some money, and it turned out bad. Luckily the seller gave my money back.. I'm dragging my feet bc the cheapest i found the 2711 intake is 275! I will let you guys know. I'm sure i will have a little trouble with the linkage and hookup, but I can't do anything without that intake! ITs just sitting there with the top cracked off!

Fun71

Have you looked for a factory intake? The iron intakes are heavier than aluminum ones but they would work just as well and be a lot cheaper.

Shaunbo13

can I use the original for the 600 edl carb? Im thinking 2711 is he spread bore flange i need for it.

76olds

Yes the 600 edl will go onto a stock intake with a 1" carb riser / without riser you will need to bend the linkage a bit .

oldcutlass

The Edelbrock carb cannot be used on a stock cast iron 4v manifold unless you use the 1" square bore adapter.

Shaunbo13

Correct, needs adapter. I don't want adapter. I don't need more air. What do you guys suggest?

76olds

How bout posting a few pics with your accumulate parts so we can have a looksie sounds like your getting close to assembly

Shaunbo13

i cannot post pics on here for some reason

grampy

If you want more power put a rear gear in it first. it most likely have a 2.73 peg leg putting in a 3.31 or 3.55 will wake it up more than any carb change. with a stock engine going to 4 bbl from a 2 bbl the power gain is small . The quadrajet is best for the street you run in the primarys 90% of the time and they are smaller then the 2 bb they will give you better throttle responce and milage improvement.with a stock or near stock 350 aftermarket intake are a waste . you might find a used intake and carb for cheap.