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Mr Maine 05-18-2016 09:49 PM

Carb size
 
I'm going to test soon with wide band, but what are thoughts on an 800 dp holley? Enough carb?

.04 over 454, 462ci
Victor junior
308 dart iron eagles, ferrea valves, 8205sp springs
Cam 231 235 and .63 lift
9.2 compression
Bore notched cylinders to match head
Gil exhaust

Looking for input on the difference to say a 850, 950 etc

endeavour32 05-18-2016 10:01 PM

800 is enough carb for your engine. I had pro systems build me a carb for an engine that probably made a touch more power than your combo. They used a Holley HP950 which flowed 830 cfm's.

Mr Maine 05-18-2016 10:10 PM

Thanks, I figured it would be OK but I see small block 350s with 950s on them (not stock by any means). Also if an HP950 only flows 830, what does an 800 flow? I plan to turn this 56-5800

mike tkach 05-18-2016 10:17 PM

800 will work but imo the 850 will make more power.i tried 3 different carbs on a similar build,750 holley,850 holley and 850 barry grant demon.the bg850 made the most hp but the holley 850 made 3 less hp but 15 more lbs torque,the engine was for a street car so it got the holley 850.

Mr Maine 05-18-2016 10:26 PM

Good info, for say 15 foot pounds I'd be better spending money on prop work.

I would think a vacuum gauge at wide open would tell if the carb is adequate, thoughts on a number? 1. .2 ?

mike tkach 05-18-2016 11:03 PM

if it has 2 or more inches of vacuum at wot either the carb is to small or the intake runners are too small.

Black Baja 05-19-2016 05:15 AM

If it's an old Hp500 carb do yourself a favor and use something else.

motor 05-19-2016 05:33 AM

Just curious as to what is wrong with an hp 500 carb?

Originally Posted by Black Baja (Post 4440716)
If it's an old Hp500 carb do yourself a favor and use something else.


SB 05-19-2016 05:58 AM


Originally Posted by mike tkach (Post 4440698)
if it has 2 or more inches of vacuum at wot either the carb is to small or the intake runners are too small.

I'm curious also, on the 'too small intake runners' causing high vacuum comment.

Mr Maine 05-19-2016 06:21 AM

They are 9022 off 420s. 76 primary 87 secondary with 6.5 power valve in the front only as it sits.


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