I attended the Mondello Performance Meet this past weekend at Byron (IL) Dragway. The first strip time with the newly rebuilt engine in the W-31. Temps were weeelllll into the 90s if not triple digits. Humidity was well up there too. It was @%^#$ hot both days. :eek2: There is about 200 miles on the motor, I'm running 100 octane unleaded and driving it around town I was getting preignition when the car warmed up. :shock: My distributor was rebuilt and recurved and set up as follows: advance starts at 800rpm, 19 degrees at 3000rpm, 22 degrees total at 4500 rpm, plus 10 degrees vacuum advance. I pulled and plugged the vacuum advance hose and still preignition. I'm currently running R45s Delco plugs. It's an automatic trans with 4.33 rear gears. At the track I put in 3 gallons of 110 and weighed the car. 3660 lbs w/o driver and at least 3 gallons of fuel. The fuel gauge is broke as I need to replace the sending unit. The first run at about 1000feet I see the tach reading 5500rpm and though :jd: I don't want to break my new motor so I back off. Trans shifted into 3rd so I got back into it. Yeah, I need to be a man I know :laugh: Second run, the mph when up by 7, I stayed into it more crossed the line at 5200rpm but I was getting preignition still. So that was it for the day. Waited until the motor cooled a little and swapped out the R45s plugs for a set of R43s Delcos. The R45s' looked fine when I pulled them. Sunday I didn't wait for the car to warm up and immediately made a run. The mph increased again to 89mph. But the driver still needs to work on his reaction time and getting a better 60 foot since those were 2.4. On the return trip I stopped and put in 4 more gallons of 110 (that fuel smells so good :laugh: ) The second and third runs I could still hear a hint of preignition ... I think Of course I also developed a slight bog off the line. But all in all I had a good time and most importantly didn't break anything :grin: I also meet DirtySanchez (Todd) and we talked for a while. His W-30 wasn't there as he's fighting some issues himself. When I got back I unloaded the car and drove it home. I keep my trailer at my brother and sister-in-laws but I live only 7 miles away. I got on it a few times and could barely hear preignition, so while the good fuel definitely helped I still have some issues. Anyone care to take a stab at what I need to look at?
And The Et. Is???????????????????????????????? uzzled: o No: o No: uzzled: o No: uzzled: o No: uzzled: o No: ET. o No: uzzled: o No: uzzled: o No: uzzled: o No: uzzled: uzzled: :shock:
Who cares what the ETs are until he gets it sorted out? The 89 mph tells us enough for now. Keep the R43 plugs. For performance, you could stand to have your mechanical advance come in much quicker -- but that will probably only aggravate your detonation at cruise, so leave it alone for now. What compression (actual) did you build to? What cam did you use? Was the cam degreed when installed? What is your coolant temp while running around town? PS: Congratulations on getting it all together (at last)! And you're already more man than the sissys who never hit the track with their trailer queens.
I know nothing about an Olds (put a 455 Buick in the last one I owned!) but it sounds like your timing is way off. 1st disconnect the vacuumn advance and check the timing. If you have to go to 4500 to be "all in" at 22 degrees and your are running race gas AND you are still pinging something is wrong. The only motors that run that kind of curve are marine engines (I run a more aggessive curve on my ski boat.) Check with some Olds experts on what curve to run.
I DO :shock: ......I ve got a w31 and I'd like to know............ whats wrong with that uzzled: o No:
back off the timing a tad,and see what happens.you might just be running hot now the fun begins,getting it tuned in.. :rant:
Thanks Brian. I'm a little embarrassed by the 15.7 ET but then again a) I now have a baseline. b) I wasn't expecting 12.90 right out of the trailer otherwise everyone would be doing it. c) the weather wasn't helping anything but thats not something I can control. Let's just say I have a long way to go before I turn in the times Dave H is currently running (at least the ones I know he's running) let along getting into the 13s which is what I'd be happy with. As for timing, we've got it at 8 degrees at the balancer when the car is warm. I believe the factory setting is 10 or 12 degrees, so it could be bumped more (which I'd like to do) but obviously that will make the pinging worse. compression is 10.6:1 and the cam is a General Kinetics grind of the original 308 degree 474 lift and it was installed 4 degrees advanced. As for the fuel pressure, not a clue but it's a Carter fuel pump. The carb, it was rebuilt and recolored by a local guy and he put in all the mods from the Doug Roe book. I sent the distr to Ole's Carb and Electric in CA where it was rebuilt (new bushings) and put on their machine where the advance curve was set up.
Chris-You had your carb rebuilt if I remember correctly. Any idea what it has for jets/needles in it? Perhaps it is running way too lean or running out of fuel from a weak stock pump. (At the track anyway. Shouldn't street driving.) That timing shouldn't cause any issues with detonation. Especially with the fuel you are running, but I'd try 8-10 degrees initial with 32 degrees all in at 3000. Like someone else brought up, was the cam degreed when put in and what cam is it? (I'm guessing a W31 repop?) If installed incorrectly it could be building a lot of cylinder pressure but with 110 octane that shouldn't be an issue. Finally, do you have a good aftermarket temp gauge in the car? (I looked but don't remember. :laugh: ) If not that's the first thing I would do as my W30 would get hot and detonate like you are describing even on good gas. If the radiator hasn't been recored it might be a good idea. When they sit for years like that they can get all kinds of nastys in them let alone the buildup from when it was driven. Hope you get it fixed Chris. And I can't wait to see it when the resto is finished. Todd
Damper shift Chris: Are you sure the timing mark on the damper is at TDC? They're known for shifting, especially on a W31 with the heavy damper ring. Mine was off over 10 degrees with only 60k on the motor. If rebuilt, never mind. If not, contact me and I'll tell you who you can trust to do that. DO NOT SEND IT TO DICK MILLER TO BE REDONE!
Chris, If I'm doing the math right, 8 deg initial plus 22 mechanical equals just 30 instead of the ~36 most cars like. And the 10 deg of vacuum advance is also lower than usually used on street cars, giving you just 40 at cruise. All in all, this sounds pretty retarded. :Brow: I've watched the temperature needle climb when timing is either too advanced or too retarded. Maybe you're generating some hot spots in the combustion chambers. I know it seems counter-intuitive, but maybe you just need more advance. It's worth a try. Heck dial in an extra 10 degrees at idle (so you're at 18), giving you 50 at cruise. Then again, if it's pinging under WOT as well, maybe that's not the problem. I know Greg's a good guy, but maybe you should check the balancer mark at #1 TDC just to make sure.
Just some random thoughts that might be helpful Chris, Do you have any pictures of the plugs you could post? If not then the next time you are at the track you could check them by cutting the motor off after you cross the finish line if you can and drift to the return road and pull a plug there. Dont let the car idle as it will mess up the reading. Here is a link to a website with some pretty good info about reading plugs correctly. http://www.4secondsflat.com/Spark_plug_reading.html I do agree with others as something is not quite right. Just my opinion I would definately recheck the balancer to make sure it is right, also I would check for a lean condition. Also have you checked the distributor to make sure the mechanical advance is functioning correctly and not sticking? If not I would check it to make sure the mechanical advance is returning at low RPM's and the springs are not too light which might not allow the mechanical advance to return to idle properly. Which in turn might cause the car to ping at crusing speeds. For future distributor settings I would think you are probably gonna need to limit the total mechanical anyway to about 16 to 20 degrees so you can run around 18 initial without the vacuum advance for a total timing of 34-38 degrees (with good gas). You might also need to slow the advance curve some to by having it start around 1500 rpms and have it all in around 2600 to 2800 rpm. That could also cure some of the pinging at well.
Distributor curve Is that 22 degrees total crank degrees, or is that what's actually in the distributor? Remember, the crank goes around twice while the distributor is going around once. 22 degrees of advance in the distributor is 44 degrees of crank rotation. Add that to the 8 initial and you'd certainly have a detonation problem.
