Fuel Carb advice

nothwoods

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Jun 10, 2013
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So I got my new motor running today and it goes pretty good for the most part. It's a stock 94 shortblock with an E303 cam, Y303 heads, and an old Performer 289 intake, in an old fox with a T5 and 3.73's. The carb is a Holley 4150 series 600 CFM, vac secondaries. I rebuilt it last year and it was on the mostly stock 302 I just pulled out running flawlessly. Still playing with timing, break-in, etc. on the new engine. Only issue so far is an initial bog on accel, and then really only if you stomp on it. I think I can tune it out with some work on the accelerator pump. Mainly wondering if this carb is a good fit for the engine, and whether anyone with a similar setup has any advice, like if they had to rejet, or if they had to go to a double pumper or anything. Main concern is I don't want to run it too lean I guess.
 
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nothwoods

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P.S. I said it was a 4150 series but I think it's actually a 4160. It doesn't have a secondary metering block, just the fixed plate type under the bowl
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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That 600cfm carb should work fine with some adjustments. If you wire in an AFR gauge and sensor it'll make tuning that carb a lot easier.
 
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nothwoods

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Jun 10, 2013
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Did a little tweaking today, it runs great for the most part. I've got everything I can get from the accelerator pump now and the bog is almost gone, but it still has a slight lag on hard accel. until the revs start coming up. Pulls great at higher RPM. I think I'm going to try a different accelerator pump nozzle. Also my spacer plate is the type with four holes rather than an open plenum type, is there any reason I should have one or the other?
 

nothwoods

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Dial in the vacuum advance too, cause and effect.
Where is your timing at?
I agree with the afr gauge
Advance is set at about 21 base, and way off the chart total... Today I found "true" TDC for the engine, and it's about 3 degrees advanced from the zero mark on the balancer. I have it set at 21 degrees actual base, and the centrifugal sends it way off into oblivion if you rev the engine. Not sure if that's a problem with my light or the distributor, but actually it's a new distributor because that was the only way I could find a proper steel gear to match my roller cam. Old engine with old distributor behaved identical to this one, and I'm trying to unravel that mystery. It has a vacuum advance solenoid but I don't have it hooked up, nor did I with my old engine. Ive been experimenting with the timing and I think it's pretty close now. I'm planning to order a spring kit for the secondary actuator, a bigger accelerator pump nozzle, and probably some bigger jets, (she really seems to be asking for more fuel), and I'll make one change at a time to see what the results are. Id love to do an AFR setup but this is a budget rig. Not trying to win races, just want it to run good and be pretty fast, it's almost there now just trying to fine tune it some. Any comments about the spacer plate?
 

nothwoods

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Actually after thinking about it, the 3 degrees BTDC mark on the damper is truly 0 degrees. So my initial right now is 18, not 21. Make sense? Confusing...
 

nothwoods

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If I set my "true zero" mark to line up with the pointer, I can just trim the pointer back to line up with zero on the damper... Then I don't have to think about this BS. F$&@in cars
 

General karthief

wonder how much it would cost to ship you a pair
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If I'm thinking right 3* BTDC is advanced so your initial timing is more like 23* (?) Anyway that, even at 21* sounds like a lot of timing to me, I have been wrong before though.
 

90sickfox

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Locked timing usually ends up around 30+ degrees.

You need that vacuum advance....unless it's a race car and full throttle all the time. Base timing for that e303 should be about 12- 14 degrees.
 
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