Ummm.... why would you be RACING a mid-11 second car without a quality tach? Here's a novel idea: shift it manually. And don't feed me that crap about being more consistent letting it shift on its own. It never bothers me. In fact I have my trans setup to short shift all the time so I can over ride the governor and hit my shift points myself.
I like the look of the stocker. I'll take it back out this winter and get it retrofitted with modern guts, and then it will be accurate. I don't want to shift it myself. I'll find out where it is shifting, and correct whatever I have to, to get it to shift where it needs to in Drive, less to do. I'd rather glance at my gauges.
Nice runs, cuz. I don't know... slicks just might be the only thing that will get all that power planted. I'd like to see it run hard from start to finish. If only so I can see the officials throw you off the track for not having a roll bar. LOL
I've used D & M Restoration in Greenville, S.C. for years. 800-722-0854 Not the least expensive, but also not the most. They do gauges, tachs & many others for just about ALL the catalogs. This way you cut out the middleman & get your parts back sooner. Tell them I told you to call. Tom T.
OK, I'm glad I am solidly in the 11's, but now I have to figure out why my trap speed was low. With 600 HP, I should be trapping up around 120 MPH I think. My gearing is good, I have 3.73's with a 28" tire (3.55 effective). Timing is good at 34*, and moving it around made no difference in the trap speed, so I left it at 34*. The carburetor is suspect to me because I don't like the way it runs on the street. It hesitates and idles rougher than it should. Gas mileage is terrible. I got 11 MPG coming back from Cecil and that is with the GV. I think it should be better than that. I'm going to have to verify my fuel pressure and check the float levels in the carburetor. The plugs look very dark to me.
Larry.. You running a widebad O2?? I was expecting you to be a little faster as well. Your 1/8 trap speed is the same as mine. Your time is a little faster 7.4 vs 7.7 but 1.63 60 vs my 1.83 makes those times very similar.. My car probably weighs a little less too.. Another factor is that for me to get a DA of 1400 feet would be a friggin miracle. My times are from a DA of 3188 ft.. Are you revving high enough to take advantage of the extra 50 HP you make between 5000 and 5900 RPM??Is that the same carb with the same jetting that it dyno'd with?? I'm still a relative newbie, but just throwing ideas out there..
Vacuum is actually pretty good Jim. About 12-13 in Park at about 1000 RPM. In gear, 10-11 at 800 RPM, idling in the high stall of the SP. The carburetor is an AED 1000 HO. Originally jetted 80 front with a 4.5 power valve, 92 rear with no power valve. JW changed that to 84 square with a 4.5 power valve added to the rear. I did not install new plugs after the drive. I really am afraid of removing the spark plugs on anything but a cold engine with aluminum heads. I have an MSD Digital 6 box. The distributor is a points distributor converted to MSD magnetic pick up by Dave Ray. JW installed a bushing which limits the centrifugal advance to a very small amount. Most of my advance is in at idle speeds. I think I am going to lock it out completely. I have a 20* start retard in the MSD box, and I am currently using it. The car starts easily hot. I have a gear vendors overdrive, so that may be sapping some HP at the rear wheels. I'd like to see 118-120 through the traps. Hopefully, I can get there. ---------- Post added at 08:07 PM ---------- Previous post was at 08:00 PM ---------- No O2 sensor, but that is on the list. My best times (2 11.67's) were not my best 60' times. I think my 60' on at least one of the 11.67's was a 1.70. Unfortunately, I'm not sure of what RPM I was crossing the line at. My stock tach is kind of useless. I am going to put the Autometer tach back in soon. Yes, the carburetor is the one it was dyno'd with. I need to verify my fuel pressure and float levels. I was reluctant to check the float levels and change them before the trip down to Cecil. I will do that for sure now.
Not withstanding the drivability issues, this is what I was thinking. It could be short shifting itself and never getting into it's full 600HP.
Larry, check with Mike Shaw.. He was out there running nearly 123 mph with one of my setups, that had tested out about 20 HP shy of yours. It would be interesting to know all the details. I know he has one of my 9.5" converters, and I think a sealed hood scoop. And he obviously has the hook situation worked out. 3 pretty big differences there, you should investigate other differences. Also, it's my experience that one end of the track, does affect the other, in both ET, and MPH.. in a heavy car. I learned that years ago when we bracket raced with a throttle stop. Our big heavy GS would not pick up the MPH, like the later Regal would. There was a thousand pounds difference between the two cars, with the same engine.. the big car was about 4 mph slower on the stop, if I recall correctly.. this was in the 118mph range. The big car ran 118-119 at WOT, and about 115 on the stop. The Regal lost maybe 1 mph on the stop, vs running 125 MPH full throttle. The stop simulated a poor launch, as it ran just the primaries of the carb for two seconds, it would snap open to WOT just after the 1-2 shift in the TH 400. Unleaded fuel colors the plugs black, so plug color is not a viable tuning tool. I am not at all surprised that removing the air cleaner improved performance.. deep drop base bottoms typically get a solid lid too close to the carb top, and we have seen some really goofy results from those "filter top" things from K&N on the dyno. I was not directly involved in that test, but I believe they actually cost HP.. I have one somewhere, I will have to test it, with a dropped base on the dyno. I would: Verify fuel pressure at WOT. Try a 92-94 rear jet in the carb, with the pwr valve removed and plugged, insure the jet extensions are there. It is possible it was leaning out, but not enough to miss.. and you have no frame of reference for "feel". You need the hard data. I have seen a motor lean out on the dyno, and go from 560 HP to 520, yet sound exactly the same. It would "feel fine" on the track. Any kind of cold air you can get to the carb will help. Get it to hook! It may be as simple as that. Fine tune the Accel pump system on the Holley.. they can be rich out of the box, for a heavy combo like yours, that does not accelerate as quickly as a lighter car. As you tune, 60' time will show you if your going the right way.. but the car must hook solid or you will chase your tail doing this. JW
Here are my time slips from Cecil, Friday 9-21-12. Car pulled hard on the second half, picking up 23-24 MPH. It's the first half that needs work.
That MPH is troubling. If you're having problems hooking in the 11-sec range, then the trap speed can actually be higher than it would be if you were dead hooking. Isn't Cecil noted for being a fast track? If having a mid 11-second real street driven GS was you goal, then mission accomplished! But something seems very wrong. If you are going to get serious about trying to get some outstanding times, then you should get slicks and a real tach to start with. Shift it yourself. (After you get your optimized time slips, then you can run your drag radials and use your stock tach.) With the MPH gain on the second half, I would think that a grossly rich or lean mixture wouldn't be very likely, although confirming with a wide-band would be a smart idea. Is the carb that you are using the same one that the dyno sheets were generated with? What are you using for an air filter set-up? It may sound stupid, but did you verify if the throttle blades are opening all of the way? What is weight of the car - no guessing, weigh it! All of the little things done right will make for a good ET, but I'd be concerned with the MPH first. RL's full-weight, iron-headed GS runs 11.50's, with some highway-oriented gears IIRC. His engine dynoed at only low 500's.
all true, when I ran my car with the 17inch street wheel set up it still trapped 120 but high 11s low 12 s and I shift mine right at 6000
What does your 72 weigh and how much HP and torque do you think it makes??? It seems to be right in the same area except for the stellar 60ft..
