update 12.75@105.26 went to island for the last test and tune of the season. since last time @ the track i bought a lm-1 wideband o2 and did some tunning. found out i was leaning out under hard acceleration in 1st and 2nd. i then installed a power valve plug and jet extensions in the rear. While the carb was off i cut the choke tower off and replaced pump cams and squirters. after some tunning i had a nice 12.8 air fuel ratio @ full throttle in 3rd gear. went to the track and was rewarded with a 12.75@105.26 w/1.79 60ft.backed up buy a 12.76 & 12.79 there is still more in it, it does have a fat hook at the top of every gear just like stage2man had said in the earlier posts. till next season thanks for all your replies, dave :3gears: ps. after looking at the air fuel logs from the track, it looks like the air fuel ratio is a little leaner @ the track. i had a nice solid 12.8 on the highway @ full throttle and on the track i have 13.2afr. that goes to about 12.2 at the top of each gear.
Just great Dave! You've cut over 5 tenths this year with minimal changes. You must be very happy. Its certainly inspiring to me as my combo is very simular to yours. Look forward to to seeing what you do next year.
thanks, very happy.it's come a long way since 9/2004 first run of 13.9 @ 99mph most of 2005 i didn't get to run because the trans blew.this year i was able to do a lot of test and tune and get the car figured out. over the winter i plan on going to a 3" exhaust dumped before the rear. right now the exhaust is 2 1/2 w/no name turbo mufflers and i'm pretty sure they are hurting performance. but there is only one way to find out. can't wait for March already :3gears:
I hear ya. Probably the only upgrade I'll be able to make this winter is a new exhaust but since I'm still running the little 2" pipes from the old 300 V8 I hope a new system will make a big difference. Again, congrats and see you in the spring. :TU:
New update, with new exhaust being the only change it ran a 12.65@107.48. 60 foot still stinks 1.79 but with tunning, that and the et should get better. The new exhaust i put together myself using 3 1/2 collector extensions that are 18" long to 8"long flowmaster tapered reducers to 3" headman "s" bends to walker ultra-flo mufflers and flowmaster tailpipes. the a/f ratio is on the lean side(13.5 to 1 a/f) and the take off has a big lean spike(15 to 1 a/f). With some accelrator pump tunning and jet changes i think et should come down to 12.4x.
Hey Dave, Made anymore improvements over the summer? Quick question. How rough does your 113 cam idle? My idle seems exceedingly rough for such a mild cam. I idle at about 700-750 in gear and aside from the usual lope I get an intermittent shudder that shakes the whole car. Its been 15 years since I had a car with a big cam but this seems a bit too rough to me. On Jim W's web site he has an engine build up with a cam that has more lift but slightly less exhaust duration and says it has a "slightly noticable lope". I'm wondering if it might be my carb or if its just the cam. Thanks for your thoughts.
haven't had much time or money for improvements. the plan is a better torque converter over the winter. my idle has a good lope to it but nothing unreasonable. i idle about 800-850 in gear. initial timming around 22 and another 10degrees of vacuum advance hooked to manifold vacuum. so 32 @ idle. when i had the edelbrock carb on it was a bit rougher, with the holley(four corner idle mixture) its a bit smoother. hope that helps, dave
Thanks Dave. I forgot about the vacuum advance. I've been meaning to hook that up but I keep having to fix other stuff. A little more advance at idle should smooth things out a bit. Still think I might hunt down another carb and see if its any better.
try the vacuum advance first, and bump the idle up to 800-850. have you adjusted your mixture screws for highest rpm or vacuum ?
I have the mixture adjusted for highest vacuum and its right on the edge of eye watering rich but if I lean it out even 1/4 turn the vacuum drops and it idles noticably rougher. I'll hook up the vacuum advance and dial it in but the carb may be coming off anyhow as I've developed a new problem today. I had it out and I jumped on it once and it ran fine. Didn't seem to pull as strong as usual but nothing really noticable. I stopped and filled it up and when I pulled out I hit it again and this time when it hit 3800 rpms or so it started cutting out and stumbling. Tried it two more times and the same thing. Cruises fine but jump on it and it falls apart. Ahhh what fun. A new impossible to diagnose problem.
update: went to island dragway 10/28. changes made since last update, removed msd digital 6(it crapped out), running stock hei with timing locked out @30 degrees. removed 100lbs from the car. results--12.60@106.58, 12.53@107.51, 12.53@107.50 the air was a little warmer than the beginning of the year when i got the 12.65.
67lbs came from the a/c compressor,brackets,and condensor.(a/c clutch fried on the way home from bop meet at etown) i ran it with a 1/4 tank of gas instead of my usual 1/2 tank(30lbs) and i lost a few pounds. usually run at island dragway.
