Holley 350 vs 500??

[ministock07]

Which carb is better for my application?? Car has 2.3 5.2 rod, oval port head, 500 lift cam, no porting or polishing, stock intake, head been milled 125 tho..car weighs 2550

[7uptruckracer]

IMO you can't go wrong with the new Holley 500 HP Ultra we just got one and its flawless. Didn't have to touch a thing. It gets up out of the hole great.

[englertracing]

IMO you can't go wrong with the new Holley 500 HP Ultra we just got one and its flawless. Didn't have to touch a thing. It gets up out of the hole great.

thats a nearly stock motor, just higher compression and a cam with .100 more lift that stock, so what do you think?

i think a 350 holley

if you really want to go fast
and i suggest you get this metering block
https://www.holley.com/products/fuel.../parts/134-276
which is meant for a 350 and already "calibrated" which means it will "work" just like a stock one out of the box
youll need a set of those little brass jets,

and one of these
http://www.innovatemotorsports.com/products/MTXL.php
learn how to use them

little story
i have a nice data acquisition system that does
rpm,
throttle postion,
cylinder head temp
exhaust gas temp
wide band O2
wheel speed
gps track position
lap times
lateral and longitudinal acceleration via accelerometers and sattelite
ambient temperature
and a few other things that dont matter

i built a totally new carburetor like really changed some stuff, sleeved it for the rules converted it to methanol from gasoline, i had to make everything, a high flow needle and seat, jets, emulsion tube, an metering needle, as nothing was available for this application and nobody had any advice. we ran it on the dyno i was scarred as (not a nice word)(not a nice word)(not a nice word)(not a nice word) we would blow it up on the track after 6 jet changes, and some drilling the dyno operator said "it looks great, as good as fuel injection"
boy was i proud
we took it to the track it wouldn't run
first of all it was running the float bowl out of fuel (thats where the custom needle and seat came in)
second after the needle and seat flow was increaced and bowl volume increaced
it was still running 20% rich at 1/4 throttle and 17% lean at full throttle..... HMMMMMMMM.....
Good as fuel injection eh?
i made a new metering needle corrected taht now guess who's little brother is winning the points championship???


but seriously the dyno's results were 20% rich at low throttle and 17% lean at high throttle...... thats a LONG ways off.

so its really amusing to me when people plop a holley onto something and think that they are so perfect that all they would need to do is eyeball the spark plug and change the main jets a few one way or another,
like seriously you wouldnt believe the wacky (not a nice word)(not a nice word)(not a nice word)(not a nice word) a fuel curve can do like at wide open throttle be rich at 5000 rpm lean at 6000 and rich again an 7000, all the while whillie is thinking with his dip stick and thinks the the plugs look great and that it really runs
so dudes stick the 500 holley on a street stock, and a mini stock, surely it will work equally well on both right? HELL NO
they require tuning of
the main jets
air corrector
emulsion circuits
power valve channel restrictions
power valve number
idle feed restriction
idle air bleed
the transfer slot exposure needs to be set right and you get it to idle by adjusting the holes in the butterfly

you also want an anti siphon hole drilled in your accelerator pump circuit
if you put the work in...... youll lap some suckers....

[ministock07]

What rpm does the 350 stop making powerat??

[7uptruckracer]

The new holley 500 is fully adjustable and $485, ours was on the dyno and the curve was great all the way through, ALOT of the tracks that still run 2 barrel LM and Mods are using it too. If you run a longer track and turn the motor you will be fine with the 500. I've run both and never had a problem with the 500 or 350 as far as performance when you get it right but the new ones have all the pull over problems solved and is fully tuneable, but we didn't have to touch it at all. So get a regular 7448 or 4412 and have to experiment or pay someone to do all the work it needs in the metering block and main body to work right or get one with everything already done to it and tubeable. if its legal its a no brainer. I even have the 350 HP carb its older but still really stout the newest HP Ultra though is fantastic and worth the money especially if you don't have to do your own carb work

[ministock07]

Track size is 1/4 oval, high rpm between 7800-8200..

[95shaw]

What rpm does the 350 stop making powerat??

Free Garage Buddy phone app has a calculator to figure cfm requirements at rpm for engine of different sizes. will give you an idea if you need a bigger or smaller carb for your application.

[ministock07]

Is the esslinger 2269 cam any good?