Something else I just thought of, my car did something like this and it ended up being a cam lobe that went away, lobe started to wear thru the lifter, it was a NEW TA cam solid too,and they said this has happened in the past, One out of 100 cams..... First they said I didn't break it in properly, then I said, "why only one lobe..."Then it made sense to them, I got the lucky one for that year.......Pull the valve cover and motor it over watching the movement of the rockers, when adjusting the valves have you noticed one seems to have alittle more adjustment than the others..That's how mine was, then watching I confirmed the problem, the valve wasn't moving much at all. I'm still thinking it's a cam "issue". Could be wrong, been wrong before, and will be again...... Gary G.
I checked the valve lash recently but didn't pay too much attention, just made sure the lash was set. Strange thing is that this motor has run the same for the past year. Straight from the dyno where everything was great to the track after install. I would think that the car would show progressive signs. Do you think so? Anyway I will pull the valve covers and take another peak. It has to be something simple I am missing.
Well no luck w/ the change of carb and fuel line routing. Still fall over hard around 5k in 3rd. Pulls good until 3rd then is starts to surge/fall over. Must be fuel.
Hey Jim, I can remember you fighting this problem at Temple. This is a really strange problem that must be fuel or air/fuel related somehow. Lets see, you now have plenty of pump and line size. You have an unblocked pickup in the tank. First and second gear run out hard so that means its probably not related to engine trouble or ignition. In third gear your speed is high, could be the rear end dragging. If it spins very easy on jack stands thats not it. Maybe something related to higher speeds? What if you gas tank does not breathe and it builds a vaccum. Maybe for some reason this defeats your pump. You could crack the cap and run it out third. Maybe air running past the top of the carb vent tube is blowing up your floats. you could put the rubber hose on the vent tubes with the small opening in the center. That is fairly common at speed. Fuel pressure to high maybe? I've heard of people having trouble keeping the bowls full because the fuel shoots out of needle and bounces the float around. 5.5 psi test run might show something in this area. Maybe? You've suffered with this bug long enough. We need to put our collective buick community thinking caps on and solve this. My head hurts already. ou:
Hi David, Yep, this is the same old problem. I just cannot seem to find the problem and I am getting tired of :spank: . It has to be fuel related. Rear is fine. I checked it in May when I switch tires. If I can make it back to the track, before I lose my mind and spend 1k on a new fuel system, I will try to vent the tank some more. I know that the factory vent is clear. I will also try the rubber hose piece and play w/ the fuel pressure. Reher-Morrision told me that their 700hp motors that are in 3200 lbs cars requires at least 280 gph electric pump and that I would need at least that w/ my weight. R-M and the folks at Product Engineering both think there is no way a mechanical pump can supply the volume to push my car into the 10's. Jim at TSP swears the pump should do the job but something is wrong. I am just not sure which way to go.
Jim, Tank vent working? I know it sounds stupid, but its possible. I actually did this once. When I use to park my car in the garage with a fuel cell, I would have to block the tank vent because it stunk like gas in the house. I forgot one time to open the vent and it starved for fuel. Like sucking on a soda bottle! Just a thought o No: Jeff
Mercy.. I guess I should check the board more often.. I had thought you had cured this problem Jim.. Just so you know, the Billet pump flows 280 GPH @ 7 psi.. Vitrually the same car as yours, Tim Hol's 3700 lbs Regal, with a 600 HP motor, the pump, 1/2 line to a fuel cell in the trunk, has run in the low 11's at 121 MPH, in full street trim. We built that car in the shop here. We have run the Billet pumps on the dyno, and making 650 HP on one motor, it dropped the fuel pressure about 2 psi, from that particular pump's 9.5 psi static fuel pressure at idle. The pump is capable of fueling twice the HP we made with that motor, with a safety margin to boot. Now, I know, that does not help solve your problem. I just wanted you to know that.. before you spend 1K to have the same issues. And, reading thru the thread, I see that it is holding 6 psi all the way down the track. So the guage must be lying to you, you have an issue after the gauge, before the fuel bowl.. or the issue is not fuel. Try cranking it up to 8 psi.. your Holley will easily take that, and that is what we always run on a race car. If not 9 psi. that's a quick easy deal.. IN testing with that pump, we used an electric fuel pump and several mechanical pumps, to see where most Holley's, Q-jets, and TQ's start to bleed fuel past the float.. the Holley and the Q-Jet easily held 12 psi. The TQ will bleed fuel at about 9, and they do typically require a regulator with my pump. Interestingly enough, we bolted on a STG 1 delco pump on that motor on the run stand, plugged the return line, and watched it create 11 psi at idle.. So when the billet pump was making around 10, it did not worry me, and I have build a number of cars with Q-Jets and Holley's, with no regulator, and we have had no problems.. only car I have every had a problem with was one with a TQ.. I have several more diagnostic Ideas for you.. but I think it would be helpful if you could post a picture of the carb, as it is setup with the fuel log and regulator. I want to see exactly where and how you have everything placed. The next place we are going is to check fuel pressure directly in front of the carb float bowl inlet, and after that, set up to do a physical inspection of fuel volume, when the probem is actually happening. If you can't get this figured out by this fall, after I get everything caught up in the shop here, It sounds like a good reason to visit Texas for an early winter vacation.
Hi Jim, As Always thanks for the input/ideas. You have gone way above the call of a vendor to help me solve my problems! Whether it be on here, in emails or on the phone. :beer I would post a pic of the log and carb set up but I have changed it. Currently I have the following: -8 line from the pump to a BG two port regulator, -6 out of both sides to a 9375 dominator. I am running two gauges, one off the regulator and another one off a -6 fitting at the regulator to a -4 line w/ the gauge on the cowl. There is about 5-6" of line between the regulator and the fuel bowls. I had the car out Sunday and everything was okay until about 5K in 3rd and the car just fell over and then pick back up. No noticable problems before that. FYI - I drove the car to and from the track w/o any troubles. When I get back in town I will try fuel pressure adjustments and adding additional venting to see if anything helps. Thank everyone for all of your help, ideas and support. It really means alot. Regards,
Hi Jim B, Does your car just lay down in 3rd gear or does it make poping noise in the exhaust also? If you run mufflers you maybe can't hear if its poping, I run open headers when I race. From what you are saying it sounds just like mine, runs great in 1st and 2nd gear but then lays down in 3rd gear and mine makes poping noise out the exhaust. You have already tried some stuff I wanted to try like a different carb. I have also replaced my ignition switch, the pickup in the dist, I replaced the Taylor wires with the 300+ accel wires, I replaced the Holley coil with a MSD coil, different make of plugs, spread out the plug wires better than they were, I moved the coil from stock location to the inner fender, made sure the wires to the ignition box were away from all the other wires. Anyway after doind all this the car went from a best of 11:52 to a 11:31 but it still lays down in 3rd gear and pops and the MPH is still slow, so it must have gained the 2 tenths in 1st and 2nd gear. Our track only has 60ft, 1/8 mile, and 1/4 mile timers so I don't have 330ft or 1000 ft numbers to compair. I still have the stock tank in mine with a second 3/8" pickup soldered in right next to the stock pickup with a blue holley pump on each pickup then Y ed together into a 1/2" line. I still have a little cheap holley regulator right next to the carb and some have said that is my problem but I have looked at alot of other cars in the pits and many are running alot faster than me with just one of these regulators. I wanted to try a different carb but you already did that and it didn't help and I don't really think that is the problem anyway. I did try a different ignition box, I had been running a Holley box and I borrowed a used MSD 6A that I tried and the poping went away but it was dead all the way down the track and slowed to 11:80s at 111 mph. So that tread about the BHJ balancers slipping got me wondering if mine has moved but I have not even unloaded my car from last year, I got so sick of all the problems and loosing first round all the time I might not even race at all this year, I want to change and check alot of things on the car before I go to the track again. I am sorry to jump in on your tread and get so long here but it sure sounds to me like we both have the same problem, what ever it may be. On of my good friends who race a 502 chevy in a monte SS said they had the same problem and fixed it when they took out the hydraulic cam and put in a solid. So I asked more about it and he said his was poping and laying down in 1st and 2nd gear also so I said mine is fine till 3rd gear. I would think if lifters are pumping up it would happen on the burnout because I turn mine higher in the burnout than I shift it sometimes if I am not watching the tach close, I have been to 6500 in the burnout a few times and it runs nice there. I am goint to put a sump in my tank and mount my pumps behind the tank so the pumps don't have to suck so hard to get fuel. I have been going camping most weekends this year, costs about the same as racing and less stress and agrivation, lol. Sorry if I repeated anything from earlier posts here. Tom
