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Well the winter's started to get to me, and I have been thinking about upgrading my carb and maybe my fuel pump. Combo is as follows:

454 + .060" (468)
World Products Oval Port heads (2.3/1.88 valves)
Crane Solid Roller Cam (238/246 @ .050 , .595/.615)
Edelbrock RPM AirGap
MSD6A Box, HEI Dist, Taylor Wires
M-21 4-speed, 12-Bolt 3.55 posi (soon to be 4.10's:confused: )

Car currently has an 850 Holley DP Mechanical Secondaries. Carb never seems to run right. Sometimes I will hit it, and the thing runs like a scolded cat, and others not as much (still fast, but not up to some of the other runs). It has teh choke-tower and all that jazz. If I were to switch from that to a 950 Holley without the choke-tower, would I see a difference? It is a street car, so would it still be driveable?

And I currently have a stock fuel pump on her. Would switching to a Carter benefit me at all?

Thanks a lot,
Chris
 

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Have you tried a search for carb recommendations? There has been a ton of discussion here. Lots of guys love the 950HP...It's not really much bigger than what you have now, it flows about 860cfm or so, but has smaller venturi's than your 850, which will make it crisper...plus the HP carbs are a bit more refined and just seem to run better. I know a lot of guys like the 850DP's, but I had one, and it was the worst Holley carb that I had. Im going with the 950HP this season on my 505, street car like yours...Im assured it's very street friendly. Do a search when you have time, you'll find tons of good info. John

And for the street, Im thinking the pump you have is probably adequate, as long as it's in good shape...but an upgrade couldnt hurt either.
 

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the choke tower with or without the blade is irrelevant, it's area is much larger than the area of the venturiis. It's a marketing thing.

Do you have a quality fuel pressure where you can see it while running wide open at the top of second and third? If not you might want to get one before blowing big $$ on another carb.

Holley has a couple 950CFM HP models that are pretty nice, one with 30cc pumps and another with 50cc pumps.

Seems like 850 should be enough for a 468, even with a 4.10. Holley has a couple 850s that are similar to the 950, good stuff.

Ever had a vacuum gauge on it, see if it's building manifold vacuum? if it's not it probably doesn't need a bigger carb.
 

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A 950 will be alot crisper than your 850 . A 950 uses a 750 main body but flows approx. 870 cfm . A 850 has a huge venturi bores making them not as crisp as the 950 . I agree with the other posts maybe your stock fuel pump is keeping up , a fuel pressure gauge will tell the tale.

Dave
 

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This past summer I had Patrick at Pro Systems "tweak" my 950HP. I provided him a break-down of my engine/drivetrain/vehicle and he customized my carb to match my setup. It was a noticable improvement over a box stock 950.

He also checked my carb on his flow bench and it flowed 824 cfm.
 

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I would have to say change the fuel pump also. If your motor runs good sometimes and sometimes not, something is not consistent. I would think if your carb is the issue it would run the same just about always.
 

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i agree with the fuel pressure gauge, not with the gear, that 454 should make more than enough torque to compensate for the 355 gears, but a 410 set could not hurt especially with a stick,as far as hp 950 carbs they are the best all around carb, maybe not the cheapest but by far the best performance carb for duel purpose cars like yours and mine, and you will see a more crispy throttle response with the 950,so i say go for it...j.m.o.....Mike
small blocks rule.....lol
 

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Chris, I too have a 468", though it's milder than yours. I've got a Crane flat solid (238/248-544/567) and RPM oval heads. I had an 800DP that showed noticable difference when I put a Proform centerbody on it. About .17 worth.
I have since changed to a 950HP that Pro Systems built for me. It has not helped at all yet on the ET (11.69, very same as 800), but sure is a lot more street friendly and more tunable with the 4 corner idle system. I don't regret getting the carb, but some here say a box stock 950HP is just as good as Patrick's. I don't know. Good luck.

Danny
 

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You should be able to do fine with an 850. For what you are looking to do on the street and rpm range it should run great. I had a 850 on my 427 +.060 for 440 inches. The motor ran 10.30's in a 3400 lbs car and shifted at 7300 rpm. I would look at fuel delivery first.
 
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