Went to test n tune to try and figure out how I lost the .7 sec in the 1/8. I got 5 runs and they were all 7.80 or 7.81 except for one where I let off. So all the clean runs I've made since switching the rear end and gears (2 at one track and 4 at another) have been 7.80 or 7.81. Good for bracket racing I suppose, but dissapointing. I tried all different things, and none made a difference. I also know now that I am not spinning based on videos and close observers, but it does "feel" like I'm spinning in the first 60 feet. I think either my engine has gone bad or the converter is not working for my setup???
'Sorry to hear you didn't get the .7 back. That is strange that a convertor would cause you to loose that much but maybe so. I'd also check the compression on all cylinders while trouble-shooting the cause just to rule that out. Best of luck and thanks for keeping us posted. Perplexing problem.
Can you reference another post or thread concerning the changes you have made compared to the setup that you had previously? Thanks. .7 in the 1/8th is a LOT! Something has to be mixed up somewhere. Later,
Here ya go Tom...mainly a rear end change that should have improved his times...this is a weird one ..http://mmb.maverick.to/showthread.php?t=22982
i lost a lot in mine and fought it for a while. have you checked the rockers. i ran 12.282 and 12.286 at firebird in practice. dialed a 12.29 first round and ran 13.29. i pulled a valve cover off and had a rocker arm stud broken. i was running on 7 cylinders. i lost a second or more. happened to me twice. p.s. if that's what happened check your lifter and make sure its all there. i just changed the oil the other day and a lifter keeper was stuck tio the oil drain plug magnet. lifter was being held together by the pushrod.
I'm gonna do a compression check, check the rocker arms, valve adjustment and valve springs this week. Based on the videos I took, it looks really slow off the line and it should be revving much higher. I'm still thinking it is a converter problem. If all tests of the engine look good, I'm still going to race in the Good Guys Nitro Nationals this weekend. After that I'm going to pull the converter and get the it changed to a 5500 stall like it's supposed to be. Thanks for all the help and support, I'll keep you all posted.
Compression check showed 178 to 186 psi (good), shaft rocker arms, springs & retainers looked good, valve's had proper lash, spark plugs looked good except one had broken ceramic, and pinion angle looked good (-3*). The only other thing that I changed was all new steering (with no alignment), but that could probably only account for .1 sec at the most right? BTW, I can only footbrake from about 2500rpm to maybe 3000 at the most.
Erick that broken ceramic could be the main culprit, while you may not feel or hear it, at WOT it could have been costin you alot, if it wasn't firing consistently the plug itself would read "fat".
I checked it before changing it and it was still at 37*. I then tried lowering the timing from 37* to 34* and there wasn't any change. I just got some new spark plugs...maybe they'll help a little. Did you get the mono-leaf springs?
I put the new plugs in and the car seems much more lively...the idle is better, it seems to rev better and the footbrake stall seems to be about 500rpm higher. I'm crossing my fingers that there will be some improvement. Pomona 1/4 mile on Friday.
