Hi Larry, I have a quick question re: total timing advance for stock GM distributors. I'm working on an L89 396/375 BBC (I know lol) but this is a good friend of mine. I'm trying to iron out some general issues with the car as I believe a few, lets say "unqualified" individuals have been monkey around with it. With the timing issue, it appears to be getting far too much total advance (52.2*) all in at 2500 rpm It's a stock original GM date coded points distributor. I set the initial to 10* for now, but believe the factory spec calls for 6* Is there a stop for the centrifugal advance weights in these factory distributors? Not too familiar with the "old" points set up any more. That much advance set alarm bells off in my head. In my GS I run an MSD billet and have it locked in at 34* tops. Maybe it's missing a stop bushing or something?? TIA Jim
Jim, It certainly could be missing a bushing. Total advance is controlled by the length of a slot under the weight plate. I have a good picture of it in post #3 on Page 1. The Mr Gasket kits have a nice brass one. A bit difficult to install with the distributor installed, but not impossible. Use a dab of epoxy for insurance. https://www.summitracing.com/parts/mrg-928g/applications
Dang, now I have to chime in. My MSD initial is jumping all over the place on a timing light. What to look for. No vacuum leaks that I've found, yet. Shooting for 14/32 with Black bushing (18*). Total is at 36 but at 2600 rpm on the Holley Sniper EFI Hand Held. It will settle solid on 7* initial but anything above that is jumping. Went at it with a vacuum gauge to max manifold vacuum at 8 - 9 in. Another 'learn' drive coming up. Should have taken software engineering in college.. lol.
If the springs are too light, the weights will flutter and the mark will move around. In addition, you can’t see true initial timing because some of the mechanical timing is already in at your idle speed. Put stiffer springs in and lower your idle down to prevent this when setting initial. Can’t the Holley Sniper control timing? If so, lock out the timing and let it do so.
Idle is about 700 - 750 w/manual trans. Don't see timing coming in before 1500 rpm but goes to 2600 to all in (on the HHH). I like your idea tho' and will give it a try. Timing control not available with MSD 6AL unfortunately. I wonder if a new box would allow it, without changing the MSD distributor? I'll ask the Holley folks. Thanks Larry.
bought myself a dialback timing light. at the factory 10 deg initial vac plugged she ran to 37 or 39 total (memory!) pulled her back to 9 deg initial and now got 35 total. thatll do for tonights dragstrip test n tune session till I can get Terry to recurve the dissy. took her out on the street and nailed the throttle both in Drive and up through the gears Low Second Drive and no pinging. Running our Aussie premium unleaded. I'll throw a can of VP Fuels Octanium in the tank at the strip just for a bit of insurance Mickey Thompson ET Street SS on the rear she wont break traction at 31psi Ill work the pressure to the track. Be interesting to see what she runs. Love my Stage 1
Well thought I blew the auto trans on first tun. Then second run tried to get us through but worked put why?...massive wheelspin
What do you mean by "blew the auto trans"? You seem down on horsepower. Your 1/8 mile speed should be at least 85 MPH+ and 1/4 mile speed about 20 MPH more than that with your combo. What kind of torque converter are you running? That might be holding your 60 ft time back. With the ET Streets you should be able to get below 1.8-1.9.
Ray, it's a 1971 455 rebuilt to 70 specs according to his introductory thread. No way to know what that really means. http://www.v8buick.com/index.php?th...55-and-drove-sydney-to-the-gold-coast.335683/
Got it, thanks. But, even a basically stock low compression '71 455 Stage 1 should run better than that with ET streets. My totally stock '72 Stage 1 with 98,000 miles went 100 MPH with just a re-curve and carb jetting. (on street radials). He has some things to work out.
Stock converter (and staying that way) Zero experience with driving this car down 1/4 Zero experience with ET Streets. Zero exp. driving an automatic. First 2 attempts the car broke traction shortly after leaving the line. (31psi in rears!) Nervous as #&*¥! After the first 2 tractionless attempts I came up for a third attempt and after a burnout (which I didnt do on the first 2 passes) the starter stopped me for dropping green coolant. Sent me back to start of staging lanes to fix it. Overflow container lid had seperated and was dumping coolant, we fixed it by draining it and washing everything down with my drinking water. Dropped rear pressures to 21psi and then had a full hours wait to get back to front of staging lanes so many cars on the night...... Ate a burger (hadnt eaten all day) Day before this my missus terminated our 6 year relationship so I had a lot of stuff on my mind besides getting the best time out of an unknown car. Sorry fellas Ill try to do better next time.. . .. Ps very tired and stressed when I did the initial post so didnt explain stuff real well at all.
Sounds like a typical 1st time at the track to me, don't sweat it. On a side note, we need to start a new thread as this really doesn't belong in the Power Timing thread.
Sure, I'll get one of the moderators to move those posts. Start another thread in the Bench, something like, "1st time at the track" Then we will get one of the mods to move the posts.
Thanks but not Ist time at track had over 200 passes in my 4 speed 351 Ford on street tyres.. First time in a Buick
