| Took the 62 back to the track |
Subject: Took the 62 back to the track by wesmigletz on 2009/7/11 20:26:44 Drove the 62 to Famoso last night (220 miles round trip, give or take). The temps were in the 90s when we arrived. This was my second time to the track since the AFR head and HR cam upgrade. My first time at the track, I had trans problems, and it was shifting at 4600 RPM, left in D. The car picked-up 25 MPH on the last half, but it was too little, and too late, trapping at 108 MPH, the same as my 47 year old camel humps and $55 re-ground cam. The AFR heads definitely kick butt, but the car was unable to get into the RPM range where they would shine. Combo: The original, numbers-matching, SD code 327/300 HP block 3.85" stroke 9.5:1 Compression Comp 282 HR on a 112* LS Comp 1.6 Gold RR AFR 195 CC Eliminator Heads Weiand #7530 Team G (Fits under a solid axle Vette's hood, with a GM drop base air cleaner) Holley 670 Vacuum secondary carb, jetted 68/71, lighter vac secondary spring Hooker 1 3/4" Super Comp Headers 2 1/2" exhaust Magnaflow mufflers 700R4, 1800-2200 Stall Conv, 5200-5300 RPM shift Points 3.36 Posi M/T 235/60/R15 Drag Radials set at 15 PSI This was my 3rd and final Pass. Air temps cooled, probably still mid 80s. Checked the timing and found it to be 33*, so I bumped it up to 38* total, then re-set the carb/idle. I dropped the tire pressure to 18 PSI. Pushed the car in the staging lanes. Engine temp 180*. No other changes. R/T .257 60' 1.814 330' 5.079 1/8 7.803 @ 89.63 (New Best) 1000' 10.179 1/4 12.184 @ 111.19 (New Best) My last time at the track, the car was picking up 25 MPH on the back half. Last night, I was only gaining 22 MPH. I was disappointed in the results, but attribute the lack luster performance to the 670 Avenger carb. I may have been able to gain a little with more jet, but stock was 65/68, and I was already at 68/71. Aside from that, I didn't have any 69 or 72 Jets with me. I think the engine wanted more carb, and I don't know if the jets alone would have made a difference. My last time out, I ran a Quick Fuel Carb, unfortunately, I couldn't get the Quick Fuel to idle, and my tear-down found nothing wrong. So, I ran the 670 carb. My previous tests, with the original camel hump heads were done with a Carb Shop Stage 3 #3310 750 vac secondary carb. The carb was pirated from my Chevelle for the tests, but is now back on the Chevelle. I can't help but wonder if the bigger carb would have gotten me the .19 seconds I needed... After this test-n-tune, I was planning to swap back to the stock heads/intake, and run a smaller 217/225 @ .050" Isky HR cam. However, I'm tempted to make another shot at an 11 second time slip. BTW, driving to and from the track, I averaged 18 MPG, including the runs. |
