750cfm edelbrock Perfromer to big for a 350?

[joelboxt]

hey, i just found a half decent deal on a 750 perfromer carb. comes with the jets and spring kit. its only been used for about 2 weeks or so. do you guys think its to big for a stock 71 350?

thanks


joel

[redz 1970 K5]

I had a Carter 750 on a stock 350. Seemed to run just fine to me. Never had a problem in the 6 years I ran that setup. The only problem I could see is maybe running a little lean at WOT. You could change the needles/jets to compensate, but then you would prob be too rich in lower cruising RPMs.

A good stock calibration on the 750 will work fine as long as the RPM's are below 5000 most of the time!

[COBALT]

Higher CFM is best effective when your engine can pull enough vacuum to make use of it. For instance my 600 cfm carb is just about enough for the mild heads and wimpy cam I have - regardless of the fact that I have a performer intake. As long as the fuel/air the carb can put out is pulled in correctly by the vacuum created by the pistons for the fuel/air part of the cycle then you should be ok. that means having an intake that will help getting it in there...in other words don't bolt that thing to a stock cast iron intake and expect it to run like a champ first try. It'll probably run a little rough - especially if you have stock heads that aren't tuned to performance.

[joelboxt]

like i said the engine is stock.. was looking at getting a perfromer intake. and the heads are stock and cam im sure is too.

so probably not a good idea to get it then? dont really know what to do? kinda want to by it.

does 200 usd sound like a good deal for 1407 perfromer pretty much new unit with the jets and spring kit?

joel

[junkyardjohn]

JOEL -- WHILE A 750 CFM EDELBROCK CAN BE DETUNED TO RUN ON A STOCK 350, IF YOU HAVEN'T BOUGHT IT... I WOULDN'T. SPEND THE EXTRA $50 OR $60 & BUY A BRAND NEW P.N. 1406 600 CFM EDELBROCK. BELIEVE ME.. WITH A STOCK 350 YOU'LL BE MUCH HAPPIER WITH A CARB. THAT YOU CAN TAKE RIGHT OUT OF THE BOX & BOLT ON. YOU MIGHT GET LUCKY & JUST HAVE TO ADJUST THE IDLE. I HAVE SEVERAL TIMES. EDEL. 1406s ARE GREAT CARB.S. I'M RUNNING THEM ON 4 TRUCKS AS WE SPEAK. JOHN

[joelboxt]

John, well i was hoping to build up an engine in a year or so thats why i ask about the bigger carb.. what kinda engine are those 600 cfm units good for? i didnt think they were much good once you got away from the stock form. what kinda HP do you have to be putting out to need a bigger unit then the 1406?


joel

[72MARIO]

If you are running that truck in year round for some reason. I would advise a manual choke. The eletcric choke is a Joke here in ontario. They are very tempature senstive.

[J.Lance]

What elevation are you at. That may make a difference also. A 750 on a small cube motor will run more efficiently at sea level than at altitude. I personally prefer a 600 on all my small blocks even with some mild performance parts. Unless you're going to do a radical build, stick with the 600. 750s are more geared towards hipo motors at lower elevations and big blocks. In the end you're milage will suffer and you will not notice any performance gains over the 600.

IMO- I love the performer electric chokes. Sure works wonders over the spring choke that's for sure and no need to mess with the manual cable. When adjusted correctly, they work excellent.

[72MARIO]

I should go a bit more in depth here. I have a 84 C20. It's got a kinda wild cam RPM intake port+polished heads all the good stuff. The 1406 carb was by no means a bolt on and go. I had a lean backfire under light acceleration. I had to change the jet just to get it driveable Its al I had avaible and I needed the truck. I still need to get a rod and jet kit to get it running right but they are kinda pricey like $120 cdn. And I am trying to get the 67 on the road for the summer so it will have to wait.

My Dad is running a 385 with the performer intake 1406 carb World S/R heads. It's built for towing and lot's of torque that carb works great good millage and nice responce. With the exception of the choke. It is horrible.

[Huck]

I go with John and Jason on this one. Been running a 1406 Edelbrock 600cfm for years on stock original 350, new crate 350 and a hi-perf 350 with high rpm cam putting out 400hp. IN each case you may have to tweek the idle or choke a bit but they run reliable and strong. I've tried a 750 and wasn't happy with the performance/mpg it gave me. To take advantage of a 750cfm carb, you need to have an engine that will breathe enough to absorb the capacity of the carb with either cubic inches or heads with a cam etc. It's hard to beat a good 1406.

[VetteVet]

I had a Holley 750 double pumper on my 1974 corvette l-48 350 and I drove it from Miami to michigan and got 18 mpg on several tanks with it. No misfires no rough running etc. All that with those dreaded 882 heads too.
I have upgraded the engine and plan on putting it back on when I get it together.
Vettevet

[Dean23]

When I built my 400+ hp small block i ran a performer rpm intake, performer rpm heads and a 750 cfm edelbrock. It ran a touch rich out of the box. I sold it to a guy with a 65 chevelle so now Ill see how it runs in his car this spring

[joelboxt]

thanks for the info, i guess i will probably get a 600 cfm perfromer 1406.. i have been looking at these carbs.. and have seen the demon and the holley's also.. the perfromer looks a little better for the road and everyday/weekend driver in the summer.. but i really dont know.. the perfromer has a similar style spread bore to the quadra jets.. smaller primaries and the larger seconaries. i would think alot better fuel mileage like the quadra jets eh?