4 bbl/tri-carbs switchover questions
 

My 69 - 350/350 intake and carb are stock but the engine has been modified; ie: bored 30 over, 1/4 cam, ported and balanced, etc., etc.. I need more fuel and air.I'm thinking ofswitching to a three duece setup. 1. Jeggs has a complete setup, by BG,for $2500. Where can I findone a little cheaper? I see summit has a 3 dueceintake but no carbs. 2.Will there be room to use the original distributor chrome shieldingwith the 3 carbs? 3. The originalintake,4bbl carb andstock air cleanermeasure 8-3/16" high. Would it require purchasing a big-block hood to accept the tri-power? 4. A twin 4 bbl setup is less than 1/2 the price, around $950. Any one suggest this as a better option? I was choosing the 3-2's due to the middle carb being the primary carb and the other 2 as extras when ya want to use them. Don't know how the 2-4's operate. I hope a couple of you have done this switchcause I need some good answersbefore I proceed.My pockets do have bottoms but I also want the best performance for the bucks I spend. Would really appreciate some feedback here, and thanks for taking time to read this. Jack

RE: 4 bbl/tri-carbs switchover questions
 

In my humble opinion... :D Unless you are going for "the look", a good single 4-barrel or simple throttle body injection kit can do what you want.

Check this out to see what your CFM should be. Most hobby engine builders over-build the carb by miles. :D A 350 cubic inch engine at 6000 RPM with 95% volumetric efficiency (a really hot cam/valve setup and tune) can only process 600 or so CFM. Anything higher just gets dumped (too rich), or doesn't actually make it to the cylinders (not really operating at open throttle).

http://www.4secondsflat.com/Carb_CFM_Calculator.html

bill.

RE: 4 bbl/tri-carbs switchover questions
 

It's my bedtime but I would really like to hear more on the throttle body injection kit. Sounds interesting. I looked into a Ramjet setup and actually saw one in Hot Springs in April. It was in a midyear andon a new gm crate motor. Talked to the guy at a show in Flagstaff in early June and he was having a lot of trouble with the ramjet. Anyway,just too involved with computer, sensors and etc. Don't want to go there. Catch you tomorrow. Thanks, j

RE: 4 bbl/tri-carbs switchover questions
 

I agree with wrwalke, a single spread bore or you could go with an Edlebrock or Holley injection system, from what I've seen you'll have $2500-$3000 into injection. Most folks think that a big carburetor is going to improve the output of the engine but it's like walke said, that 355 cu. in. can only process 600-700 CFM at it's best, GM put alot of time and money into the Q-Jet, it's a good carb and can be set up to do anything you ask of it. Just curious what your referring to when you said "1/4 cam".

RE: 4 bbl/tri-carbs switchover questions
 

Hey Buckshot. Sorry to be so tardy in my answer. We have been in Iowa for the past 2 weeks. Wife's brother is taking cancer treatments and she wantred to be closer. I went to the Good-Guys show in Des Moines while I was there. Saw a couple awsome Midyear Vettes there. The 1/4 Cam was a type error. I meant to type 3/4 Cam, as in 3/4 racing cam. It's a performance cam with higher lift lobes and quicker open/close duration. Keep in mind, I am from the old school and if this has no meaning to you, ask me again and I will be happy to explain. Meanwhile, thank you and the others for the suggestions. My real goal is to dress up the engine compartment a little. I may go with one of the Edelbrock, Alum. intakes. It would brighten things up a little.j

RE: 4 bbl/tri-carbs switchover questions
 

I was wonderin' too... That is a mild cam.

I see however that it was corrected in the next post[sm=smiley20.gif].

RE: 4 bbl/tri-carbs switchover questions
 

Hay alive69, I put an Edelbrock Performer manifold and cam in a 355 in one of my trucks, I was very happy with the performance and MPG and the manifold looked good. Now they have the polished jobs that would add a little sparkle.

RE: 4 bbl/tri-carbs switchover questions
 

In my day, the "full race" cam was too rough for the street. Couldn't keep it running. A 3/4 race gave good performance and sounded mean, especially with dual glass packs. You got a lot of attention at the A & W drive-in from the guys and the car-hop gals on roller skates delivering those coney dogs and root beer in the frosty mugs. j

RE: 4 bbl/tri-carbs switchover questions
 

You got 11 minutes to think this one over...

http://cgi.ebay.com/ebaymotors/Corve...mZ200129495279

No bids tho'; they'll have it tomorrow.

Still might be intake limited, but worth considerin'...

RE: 4 bbl/tri-carbs switchover questions
 

Do you have the specs on the cam? andhow much gear are you running, this will help determine intake and carb combo. On the 350 in my 61 I run an Offenhauser Port-O-Sonic single plane with a Holly 3310, runs real good. but the car has 4.56 gears.

-Rich