Not new to this site just a new screen name,(couldnt remember password).
The problem is, it pops(goes lean and backfires) at about 4300rpm in first gear and i leave at about 3200 and then just picks up and runs 12.3/12.5 on widebands all the way thru 7000 rpm in both of the other gears with no pop. I thought it was the fuel sloshing from vents into the venturi but i put a hose from vent to vent and vented the middle of hose like the railcars do. I do have a stock hood on it and was told by a ten five friend of mine that REHER-MORRISON told him that any n/a engine needed at least 4 open inches above the the body of carb, i dont know if any one has heard of this issue or has had it before but its slowing me down almost a full second and i wanna hit the 11's before i spray this thing. So all in all PLEASE HELP?!?!?!?!?!
The set up is as follows:
2000 Z-28 10 pt cage, full interior minus speakers and ac, subframes, 7.5 10 bolt mini spooled 4.10 gears
383 stroker-eagle crank and rods, wiseco -8cc dished pistons
243 heads-total milled 52 thousandths, 2.02/1.575 valves, p&p'd, prc gold springs and titanium retainers
camshaft-571/573 lift, 240/240 duration, 112 lsa
hardened 7.350 pushrods
1-3/4 headers with turn downs for wide bands
victor jr carb intake
holley 4150 street hp 950cfm mechanical sec. 86ft/87rr w/pv plugs
msd 6ls box
timing- [email protected]
ramped to [email protected]
, 33* all the way to 6000rpm then ramped to [email protected]
redline at 7000rpm
spark plugs- ac delco stock style iridium @35
transmission-th400 automatic(nothing special just a shift kit)
weight- guesstimate 3600?
60 FT: 1.71
1/8 ET: 7.79
1/8 MPH: 90.34
1/4 ET: 12.11
1/4 MPH: 113.24