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I’m using a wide band from Speedhut. Lowest gauge on the right side of the dash. I have Speedhut in two of my cars. Seem to work well and are customizable if you’d prefer.
Cheers.
702915
 

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Discussion Starter #24
Update: went w the dual innovate dlg 1 346 bucks a little pricey but it utilizes 4.9 02 sensors w the 18x1.5 bung size for anyone who wants to know. The harness is a little long but it actually worked out great how I installed it. I put it on a rocker switch w light on my pod it was easy to program and I have extra connections for piggy backing other loggers or ecu stuff. Came w a data port for a laptop I can run a program on.. haven’t messed w it yet. Also u can swap face colors black or whit I chose white it comes w both so far it’s working great already I tuned my carb warm at idle w it and it’s running better I was close but now I can see what’s goin on I’ll post more as I use this new tool
 

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1964 Chevrolet Chevelle Malibu 4 door
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You put it on a rocker switch? Just making sure you don't have it shut off while the car is running, think this can lead to a fouled sensor.
 

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Discussion Starter #26
You put it on a rocker switch? Just making sure you don't have it shut off while the car is running, think this can lead to a fouled sensor.
yessir it’s on before I start it 🙂 just another part of the ritual now lol
 

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Discussion Starter #27
Kk so what kind of and numbers would you be looking for I’m 13.5 ish (bounces around) at idle and when I stomp it Itl grab up to 16 for a sec which I’m guessing cuz of the extra air. Wot is between 14 and 12 I’m running a 770 sa w vac secondaries and plain spring. 70s up fron and 72s in the rear my fuel pressure is at 5.5 at idle although I can see my gauge from inside the car so there’s no telling where it’s at at wot what do u guys think .... on the right track should I roll purple spring then try yellow first then maybe go up 2 jet sizes on primary and secondary?? I feel like I may be running a tad lean here..... my plugs look brand new that’s what’s tripping me out
 

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Discussion Starter #28
You put it on a rocker switch? Just making sure you don't have it shut off while the car is running, think this can lead to a fouled sensor.
It stays on 24/7 w a nice blue light. I usually shut my car off w the dead switch off the trunk
 

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1964 Chevrolet Chevelle Malibu 4 door
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Kk so what kind of and numbers would you be looking for I’m 13.5 ish (bounces around) at idle and when I stomp it Itl grab up to 16 for a sec which I’m guessing cuz of the extra air. Wot is between 14 and 12 I’m running a 770 sa w vac secondaries and plain spring. 70s up fron and 72s in the rear my fuel pressure is at 5.5 at idle although I can see my gauge from inside the car so there’s no telling where it’s at at wot what do u guys think .... on the right track should I roll purple spring then try yellow first then maybe go up 2 jet sizes on primary and secondary?? I feel like I may be running a tad lean here..... my plugs look brand new that’s what’s tripping me out
Might need to up/tune/tighten the accelerator pump cam to get rid of that lean spike when you hit the throttle. WOT should be around 12.5 for performance. LS tuners usually shoot for 12.9 but we're dealing with injector per cylinder and matched intake runners/combustion chambers. With the inconsistencies of sbc/bbc intake runners and their distribution of fuel you need to stay richer in order to avoid burning a cylinder up. I know Engine Masters on Motortrend have done some cylinder to cylinder distribution testing on the dyno as well as Richard Holdener on youtube.

Unsure of your combo, but here's a vid on Holley accelerator pump tuning:

 

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I agree with Hotwire.

You said a 770 So I'm assuming its an 'Avenger Carb.
13.5 AFR avg. at idle is good (when warmed up). Carbs are leaner at cold startup and richens as it warms. I have no stumble at WOT and my AFR spikes to 15.8 for a split second and then dives to 12.5 and holds. As long as there is no stumble, the 'quick' spike is due to the primary's and secondary's quickly adding air. I say quick because if it spikes and holds or slowly drops, then its needing fuel as it builds RPM.
Hotwire's
up/tune/tighten the accelerator pump cam to get rid of that lean spike when you hit the throttle
. You're close though.

As for little additions but not needed, do you still have the stock solid fuel level sight plugs? Its beneficial to have the clear sight plugs to verify you have the float bowls set properly. Also if you have a fuel pressure regulator, Id up it to 6psi min and preferably 6.5psi max even though they say 5-7psi.

Mike
 
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Discussion Starter #31
Ok I added a rio 30cc kit I had off another carb w a diff cam I’ll re visit and try a few diff cam profiles I have no stumble what so ever tho. I did feel my fuel pressure was a little low I got sight plugs and yes it’s a 770 street avenger. Bowl levels about an 1/8 to 1/4 to the bottom of the plug do sights need to be half?? I’m used to the old school brass flat head lol so the diff between 14 and 12 is what in terms of jet or spring differences I don’t have an idea of what to gauge between the two numbers. I don’t mind playing w everything I got plenty of time on weekends and I drive the car maybe 3 times a month lol thanks for the replies on this issue
 
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