ok i am wondering if maybe anyone is running something like what i am.. i have a 350 30 over im told that is a 355 i will beleave that...i have 11to1 forged dome pistons . 30 over i have seen them with my own eyes ..it has pink rods 4bolt ballenced steel crank.i put a set of eddy rpm 70cc 195 runner heads on it with 1.5 full rockers made in usa no *** crap gold comp cams...i have a 480 lift cam it is a 280h cam from comp cams......i have a pro comp dule plane intake an hei distributer 8mm wires.......................i have 5 carbs for this engine and dont no which is the best but i do no i spent 2500 dollers to try and figure this out not to mention the gaskits and jet kit and all that crap.....here is some of the new in the box carbs i have 750dp..mec.secandarys..650 dp.mec.sec. 670 street avenger vac sec.. 600 eddy ...all these carbs are new.....i also just did a 411 rear and a 700r4 street strip tranny conversion all in 3 weeks i spent lots and lots of money even got a 2600 lock up converter.............all this good expensive parts and this car wont burn tire with a jet pushing it ....im ready to pack it in and sell the dam thing...... i have the timeing lockt out at 35 at 3k rpm's my problem is i think this motor shuold lite the street on fire but it dont spin them for nothing ....any help wuold be nice

 

670 street avenger vac sec, but if it wont burn the tires with 411 gears then something is ****** up.

 

your telling me i dumpt 25k into this car in 7 months got all good top of the line parts and it is a dog.. no one can seem to get this car to tune rite i have had 9 difrent timing experts f it up than i had 5 idiots have me buy carbs that cost 450 a shot its just to much shyt.......

 

I would say your convertor is a little on the small side.. I had a similar setup and use a 3000 stall and could break the tires at will.

 

Yep.

 

Maybe this wants to run upstairs a bit... put a bigger number on your converter... 3000-3500

 

Your sure it was a 4.11 ratio installed ?

 

Wire your lock up so you can choose when it happens

 

Hate to say it but if you took their advice and layed down cash on 5 carbs to try and remedy this problem then they aren't the only idiots.

 

Did the installer check or degree the cam when it was installed or was it just pitched in there and then everyone said "Great" it'll run now ???

 

Hey any carburetor is only as good as what it sits on !

Small bore carbs on the right setting are tire fryers...

Larger bore carbs come to life with more air flow...

 

the cam wasnt degreed nor was it on my last 7 motores.. as for the rear it is a 411 the the converter is defnitly a 26to3000 stall as for being to small mostlikely it is not as a 480 lift cam is building power from 18 up ..i no this is a carb problem if i install the 750 it runns grait but smells like raw fuil if i install the 670 it dont have enughf .....i think anyway...

 

my car loves the 750dp but it smells like gas to much

 

The advance of a cam needs to at least be understood for it to be installed properly, and they should always be checked. Then you can determine if you need to change the advance or not. A 480 lift cam is prettly mild these days, I'd start with understanding the tune on the engine first. What's the initial timing set at? What's the advance curve look like? As far as the carb is concerned, that engine will only pull so much air through it, I don't care if you have an 1150 on it. There are calculators out there (sorry, don't have link to one at the moment) usually from places like Holley, that'll tell you what size carb you really need. It's a factor of displacement, air flow and RPM as I recall. Then it's a matter of tuning the carb to the particular engine specs.

 

Everything now has to be tuned to work together. To check on the carb settings, I recently installed an air/fuel ratio gauge. (AEM wide ratio analog- $200 at Jegs.)
I found my (professionally rebuilt Quadrajet) carb was 1)ferociously rich at idle, 2)not bad during a cruise, and 3)way too rich at heavy throttle, and 4)lean at WOT. Using the gauge, and getting new jets and rods, I was able to get the numbers much better (after quite a bit of trial and error). Now it starts and runs like it's fuel injected.
Get yourself educated on your carburetor, first, before you spend any more money.

 

I bet you have a timing/ advance issue and/or a vacuum leak. Quit hiring morons and do it yourself. Put the 670 street avenger on it, it is the perfect carb for your build and should be close to right on out of the box, check for any vacuum leaks and use this info. Make sure your dwell is right. You will need a dwell meter and timing light. Make sure your mech advance plate works freely and buy a dist spring (recurve) kit for under $10. BTW my bone stock 72 with an L48, auto, 3.08 gear would roast the tires for 1/2 block from a dead stop. It is all about the tune.

http://www.lbfun.com/warehouse/tech_...t%20Timing.pdf

http://www.lbfun.com/warehouse/tech_...ance_Specs.pdf

 

OK, here's the link for you:

http://forums.corvetteforum.com/c3s-for-sale-wanted-56/

 

GOOD ADVICE...

Does your tuner involve an Oxygen Sensor ?

 

Im trying not to spit my drink all over this 1500.00 laptop!!!!!! This was amusing.

I agree with the 670 though. Even try the 600. Im running an Eldelbrock 600 on my 350. Stock gm vortec heads, comp cam 268, rpm air gap intake, complete eagle bottom end but all stock sizing. Car made 397/422 with a Holley 750 vac sec but fuel washed the rings inside of 10,000 miles. Took the motor back to the builder under warranty and got a new one. Complete new motor-took the Holley off and set the 600 up there. Gained all kinds of throttle response, mileage and driveability. Has an elec choke too

 

cam degree MUST be checked. the dots have been PROVEN to be off on some timing sets....JMO