PDA

View Full Version : Popping in first gear


1KWIK72
09-05-2006, 11:27 AM
I have an intermitant pop or studder at the top of first gear only. It varies in intesity and when it happens. Its severe enough that it usually knocks a couple hundreths off the 330 time. The 60's are pretty consistant but once in a while it will be bad enough to affect the 60 as well. It never happens in 2nd or 3rd just first just before the gear change. Its an 18* 406 I shift it at 7500 high side rev limit is set at 8400. It started doing this in the spring and I changed the intake gaskets, plugs, wires, and switched to a crank trigger. It seemed to go away until I went to Route 66 for Super Chevy. I did notice there that the barometer was much higher than my home track because it is at a lower elevation. I tried adding 3 jet sizes and backing off the timing with no help. I put the jetting back to where it was and it started running good again back home until this weekend. I did break an inner spring a couple weeks ago. So I just installed a brand new set that were all checked before installing. The fuel pressure is 7psi all the way down. I have jet extensions. The timing is at 30* and doesn't move. Because its intermitant I suspect an electrical issue. Anybody got any ideas?

Jim Monson
09-05-2006, 05:37 PM
Could it be running out of fuel down low because the launch is making the fuel pressure drop off?

1KWIK72
09-05-2006, 06:45 PM
Not that I am aware of fuel pressure seems to be stable on launch and the engine recovers on the shift ok and is fine all the way down the rest of the run. I did find the float level a tad bit low (when I was at Joliet) but the car ran good that way previoulsy and ran the same (poping) after I raised the level. It also went back to running good for a while until this last weekend.