Hey guys, I was wandering how far to advance my ignition timing on my car? I heard that you can get better throttle response, fuel mileage, and bla bla bla. How far can I go without hurting anything? Turning it to the right advances it , right???

 

That statement is true, to an extent. Ive found if i run my car at 12 degrees base timing, it runs better than at 10. after that i start losing mileage, but gain power thru the RPM band. And if i remember, you are correct, turn it clockwise to advance the timing. Remember to disconnect the EST if youre going to set timing.

 

Leave the base timing set at 10° and get someone to tune your computer with a new chip. The timing table your computer goes off of is definitely fubar (along with other tables), fix that and you'll start seeing some of the results you're after. Turning the distributor is pointless with a tune and could cause physical damage to your engine without. FYI, the chips in the parts catalog like hypertech and such will not correct this, you will need it custom made by someone who knows what they are doing.

 

well, i tried messing with it.I tried going both ways, but wound up having the best throttle response clockwise, about 1/8th of an inch. how much is that? And I have lost ALOT of fuel mileage. i'm getting maybe 14 to 16 mpg now. And i was really stupid not to mark anything before i did it, so do any of you guys know how to set it back to stock timing? and I didn't unplug anything when I did all this. Was that a big no-no?

 

First off, you need to get a timing light. You will have to hook it up to the number one cylinder plug wire (next to alternator) and the battery. Disconnect the connector for the EST (tan wire with black tracer) that comes out of the main harness by the right strut tower. The timing tag that you point the light at is on the left side of the engine and turn the distributor till it lines up with the 10° mark. Tighten the distributor and recheck, turn off the car and reconnect the EST connector and call it a day.

 

I have a 91 v6 3.1

So I just checked my timing is at 8*

I'm getting pretty bad gas mileage only 21mpg used to get 27

So what should I put my timing at?

10* , 11*

I also bought that chip from hypertech so should I set it to 10 and let that chip do its job it's claim to give you 14hp and improve mpg.

My goal isn't HP just want best MPG

 

Dont ever set the timing without a light. Thats just asking for trouble.

Your best to just stay at 10* BTDC when you set it(this is stock). You can advance it a few degrees but if your really trying to pinch out hp from tiing alone, id sugest tuning it or at least getting a aldl cable and using a lap top to see how much KR your getting from cranking the timing up. Id hate to see a litle V6 pushing 8*+ of timing over the reference angle and knock it self to death.

 

If you havent installed the chip yet, return it, its a waste of money. You'd be better off spending that money on maintenance to get your MPG back to where it used to be than to use that chip. If you read up on them, the general consensus is not to use them.

 

What kind of maintenance? 02,Egr,plugs,injectors, relays, new radiator, ignition module changed, I have pretty much done everything u can.

I think my rim size is hurting my gas mileage along with my timing was at 8 and the 3.27 ratio is higher than my stock 3.08 my goal is to get the best mpg this is my cruiser commuter.

(Yes my dad has a light about to set it back to 10*)

 

3.27 rear end ratio?? IIRC it is 3.23 (auto) and 3.42's (manual) for our 3.1L's

You have a different rear end in there? Out of a TBI or something?

If your getting 15-20 in town and 20-25 on the highway your about where you should be. Our cars were decent on the highway but never were really good in town. Driving habits are crutial. As I can get 25mpg's all day followed by a day of getting 10-15mpgs...lol

Sounds like you've been doing good mantinance. Have you been resetting the ecm each time you did one of those mantanance proceedures? IE the injectors, the ICM, stuff like that.

 

My rear end is a 1989 iroc it's a 9 bolt 3.27 ratio auto4 disc. I'm getting 21.8 highway and driving like a grandma. I think my mileage is off meaning if I meter goes 1 mile maybe I went like 1.2 miles. My speed is correct. O2 changed, egr changed, filter, my CAT I think it's pretty much toast which sucks they are expensive.

So with my larger wheels 19x10 in the rear and 18.5 in the front and CAT, and my timing was retarded off wasn't even at 8. I set it to 10*

So that should help a little.

I never reset anything though I don't know how to do that.

 

Its not far off. You had 3.23s origanlly in that car. Though the larger tires will set if off some more. How large in diameter are the tires?

 

Hmm not sure they are low profile tires I can get dim on them later.

I'm trying to sell them right now since I'm a little **** as u can see on gas mileage. Found the double line irocs 16 inch.

 

if u want to improve milage buy the lightest possible rims u can get.
i would buy a set of 15x8 or 16x8 weld draglites. as they are like half the wieght of the oem rims
the iroc rims are very heavy, also u car would have came with 15 inch rs wheels

 

16x8 ok off a 1989 iroc-z they are the double line or are those too heavy ?

Or

16x8 1991 RS alloy are those lighter than ^