600CFM to 670CFM worth the effort?

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Slantsix64

Slantsix64

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What’s up dudes, I got a 5.9 Magnum ported heads, Mild camshaft 220@.50 .480 lift. 3000 Stall converter 3.91 gears currently has a street warrior 600cfm Holley. Car runs a 8.3 in the 1/8. I got a used street avenger 670CFM wanted to slap on.

My Question is the Switch from 600 cfm to 670Cfm worth the effort?
 
Given that the effort is pretty low, maybe. I suspect it won’t be a major seat of the pants difference, though if you’re hitting the drag strip I would be interested in the results.

I went from a 570 holley to a 650 avs2 on my magnum with similar specs and noticed a bit more top end but not a ton more performance overall. Thinking of trying out an 800 double pumper at some point to see if that makes a bigger difference.
 
Make it worth your time... 750 double pumper. You need it.

but yeah, easy enough to try the swap from what you have if you want to...
 
I might just leave it alone, unless I get a double pumper type carburetor! The carb pulls hard and quick and it is tuned well.
 
Ported heads,360 c.i.,3000 stall,and 3.91 gears SHOULD run faster with more carb.Like the others I thank a 700 or 750 double pumper would be the next step. Since you have it you have nothing to lose by trying it.If it is jetted properly and goes faster I would then try a 750.
 

Those 670 SA's sucks. Way lean on the 340 I tried one on. I believe they have they same throttle bore and venturi size as a regular ol' 1850 Holley. Since you have it, go ahead and see for yourself. I'm with others though. Sell it and go with a 750 dp or even a 3310 if performance is what you're looking for.
 
I’m actually going to be dragging racing at a 1/4 mile track for fuel fest at the Pomona in n out track.

NHRA Rules I guess if your car is faster than 8.5 in the 1/8 you need a driveshaft loop, and a functional neutral safety switch lol
 
Slantsix64 said:
I’m actually going to be dragging racing at a 1/4 mile track for fuel fest at the Pomona in n out track.

NHRA Rules I guess if your car is faster than 8.5 in the 1/8 you need a driveshaft loop, and a functional neutral safety switch lol
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a functional NSS is something you should have anyways. Our track is IHRA, and at 8.5 we wouldn't need a loop unless using slicks or drag radials.
 
So I might run the 670 street avenger, I’ll probably put a 3310 or 4150 primary metering block, I believe the stock avenger metering block is horrible causing lean issues.
 
Slantsix64 said:
I’m actually going to be dragging racing at a 1/4 mile track for fuel fest at the Pomona in n out track.

NHRA Rules I guess if your car is faster than 8.5 in the 1/8 you need a driveshaft loop, and a functional neutral safety switch lol
Click to expand...
When?
 
Update, ended up getting my Hands on a 3310 750/780 Cfm vacuum secondaries. Finishing up the rebuild on it.

Added a quick change secondary pod, and a secondary metering block I had laying around. Had enough extra gaskets to do a complete rebuild.

I got the carb for $50 this past weekend at the Spring fling.

Going to Run 70s in the primary and 78s in the secondary. Yellow spring in the pod, running a 2800 stall probably will need the secondaries to come in quicker with 3.91s.

Pink cam with a .31 squirter 10.5 PV
 
I don't get all these SA670 slams, I had a customer w/a MonteSS that had a 350 w/WorldProduct iron heads on it, & His complaint was lagging after tip-in but rich once it was opened up. I welded some O2 bungs in it, & yep, the FAST Dual channel showed exactly that....lean on the primaries post-shot & fat once the secondaries opened. It didn't take long for Me to check & find the fuel levels were screwed OOTB, you guessed it, ft low & rear high.....imagine that. After taking the time to be sure I'd nailed the floats, We saddled up & took it back out, that thing rocked & rolled & drove like a dream....He coudn't stop smiling about it. I didn't have to change a thing & that SA670 was right on, the FAST showed it clearly, & I recorded (2) events....practically carbon copy runs w/great AFR's.
 
Killer6 said:
I don't get all these SA670 slams, I had a customer w/a MonteSS that had a 350 w/WorldProduct iron heads on it, & His complaint was lagging after tip-in but rich once it was opened up. I welded some O2 bungs in it, & yep, the FAST Dual channel showed exactly that....lean on the primaries post-shot & fat once the secondaries opened. It didn't take long for Me to check & find the fuel levels were screwed OOTB, you guessed it, ft low & rear high.....imagine that. After taking the time to be sure I'd nailed the floats, We saddled up & took it back out, that thing rocked & rolled & drove like a dream....He coudn't stop smiling about it. I didn't have to change a thing & that SA670 was right on, the FAST showed it clearly, & I recorded (2) events....practically carbon copy runs w/great AFR's.
Click to expand...


It appears that tuning is becoming a lost art faster and faster every day.
 
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