View Full Version : 87Brougham Ignition Timing

05-02-06, 08:28 PM
I want to set/correct the ignition timing of my 87Brougham. On the label, it says to remove the ground from the diagnostic lead DC3. I don't know where that is. If someone knows where this is, or what I am talking about, please help me. I had a friend of mine rebuild the carb, and I have done other major maintenance to this car. This is one of the only things setting me back from getting 100% out of the motor.

05-02-06, 08:42 PM
IIRC that is not for the Olds V8, Chevy V8's used it that way.

In the Olds V8 you need to short pins A-B on the ALDL to put in timing set mode. Then set for I think 10 degrees timing.

The Olds powered guru's here can help better.

05-03-06, 09:23 AM
'87 Olds 307 here. You have to ground out the diagnostic connector under the ashtray inside the car. I forget which pins off-hand, since I have this handy little Chevy tool that someone bought me, but I'm sure you can google that up. Base ignition timing for the 307, believe it or not, is 20 degrees advanced. Anything lower than that, and that 307 becomes and even bigger turd than it already is.

05-09-06, 05:58 PM
Yea I checked it out on alldata. Its the A & B pins, the same pins you use to pull engine codes. Thanks for the help guys.

05-09-06, 05:59 PM
Any of you guys ever have problems with DTC34. Something with the vac sensor, it relates to the computer controlled ignition timing.

05-11-06, 01:29 PM
Whoa whoa whoa I've been trying to time a 85 Buick and it's been giving me absolute hell! So you mean for the olds 307 I have connected the A&B pins and THEN set timing? Engine running, connect pins, set timing, disconnect pins...and then only the timing is set?

05-11-06, 01:46 PM
Yes, exactly. I think you disable something else too. Oh, and timing is set at 1100 rpm isn't it? Look under the hood, the underhood sticker tells you how to set it exactly.

05-11-06, 04:23 PM
There are three 307's here, 85,86,88. The olders ones say rpm at 1000@ 8 Degress, and the 88 wants it 1100 at 20 degrees. I'll give it a try, I believe in 88 they put in Electronic Spark Control, but I guess these engines love to run high timing.

Thanks N0DIH! I'm so giddy I've gotta try this asap!

05-11-06, 05:37 PM
Don't forget to unplug the Thermac (on the air cleaner) and plug it with a golf tee or something before setting timing. Also jumper A and B on the plug WITH engine running and after setting timing unplug WITH engine running so you don't set a code.

On Olds 307s 20 degrees BTDC @ 1100 RPM using timing light on cylinder #1.

PS, My 307 is very not like a turd.

05-11-06, 06:56 PM
I think that was it, the Thermac. Back in the old days it was the Vacuum Advance.....

My 307 Olds in my 85 Cutlass was a nice runner. My 350 Olds that replaced it was much better....

05-12-06, 12:23 AM
Yeah I've been using a pencil to block the vac advance when I'm setting it, and tried setting it with the timing light and manually without to no avail. I guess the whole time I didn't do the step with the A-B which is why it was always running rough. I just hope the times that I desperately needed the car and drove it with some bad timing that it is not damaged. I drove well under the speed limit and didn't want to push it, but needed the car as I said.

After that's done, I have to figure out how the heck to get more ZIP out of the 307. I can't even spin tires on gravel...shouldn't the torquemonster that it is be at least able to do that?! Is that so much to ask! KHHAAANNNNN!

05-15-06, 10:04 AM
I don't have my Klingon dictionary so I'll have to guess on that last word.

Try these for 307 performance:




Have fun!

05-15-06, 07:45 PM
Bookmarked and bookmarked! Thanks for the links.

In Star Trek II: The Wrath of Khan, when Khan tells Kirk that he's not going to kill him but in fact leave him stranded on a barren planet, Kirk screams back at him...KHAAANNNN!!!

It was a classic Seinfeld moment too! :bouncy: