Timing Retard Question

[1987 GN]

Just took the GN out for a spin. I have had a bleeder valve installed for a while and I keep it closed all of the way usually which limits me to about 15lbs of boost. I am running a Jay Carter 93 octane street chip, walbro 307, afpr, cold air kit, THDP and JC 2 1/2" dual exhaust and everything else is stock. I always fill up with 94 octane gas. Before I put the bleeder valve in I always had 2-3* timing retard so I put it in to lower the boost and now I always have 0*. I tried opening the bleeder valve tonight about 1/2 turn and I made 3 full throttle runs, two from 55+ mph and one from 0 mph. I got between 6* and 12* timing retard on each one. As soon as the scanmaster showed the large number of degrees of timing retard I immediately let off of the gas. I closed the bleeder valve and made another run and got ~ 2* timing retard.

1. Do you think any damage was done to the car with the 12* timing retard?

2. Does this type of varying timing retard seem out of the ordinary to anyone or is this just typical?

Thanks in advance for your help!

 

[blackbuick87]

1. If you did mine could blow any minute because I have been to 12 several times

2. What did the boost go to when you got the KR? O2's?

 

[azgn]

you are just slowly but surely eating away at a head gasket....keep the boost turned down on pump gas or eventually you will regret it.......

 

[1987 GN]

Originally posted by blackbuick87
1. If you did mine could blow any minute because I have been to 12 several times

2. What did the boost go to when you got the KR? O2's?

The boost shot up to about 19lbs and the O2s were either 789 or 829 I do not remember. Thanks for the input so far guys.

 

[blackbuick87]

So the timing retard was purely due to the increased boost. There is nothing wrong with your car you just ran out of octane. Dont open the valve without race gas or alky and you will be fine

 

[TurboDave]

What amazes me is that you got that much knock retard using 94 octane gas and 19# of boost

I would expect what you saw if you were running 91 octane Calif. gas It was a regular occurance anytime I got over 16# of boost out there.

Here in WI where the octane is a genuine 93 (non-oxygenated) octane, I can now run just a pinch over 19# of boost in 1st and 2nd, and can run a full 17# in 3rd. This generally yields less than 1 degree of knock retard on the 2-3 shift.

What you're seeing is nothing more than octane and boost mismatch. You'll have to find a boost level with your gas that doesn't yield any more than a degree or two of knock retard. Then you'll have found the limits of your gas.

Is MA gas oxygenated? or otherwise "messed" with?

 

[blackbuick87]

Wow we replied at the exact same time. SPOOKY

 

[1987 GN]

Originally posted by TurboDave
What amazes me is that you got that much knock retard using 94 octane gas and 19# of boost

I would expect what you saw if you were running 91 octane Calif. gas It was a regular occurance anytime I got over 16# of boost out there.

Here in WI where the octane is a genuine 93 (non-oxygenated) octane, I can now run just a pinch over 19# of boost in 1st and 2nd, and can run a full 17# in 3rd. This generally yields less than 1 degree of knock retard on the 2-3 shift.

What you're seeing is nothing more than octane and boost mismatch. You'll have to find a boost level with your gas that doesn't yield any more than a degree or two of knock retard. Then you'll have found the limits of your gas.

Is MA gas oxygenated? or otherwise "messed" with?

My thoughts exactly!
I have been reading on here how with the Sunoce 94 (like I use) people are able to run 17-18lbs easily. So I figured I was probably doing something wrong in the past. I opened the bleeder 1/2 turn thinking this would probably give me 16-17lbs. Instead I get 19lbs and a ton of timing retard. Either the gas is messed with in Massachusetts which I doubt since I have not heard anyone else mention it or my car prefers 15lbs on 94 octane and that is it. Very strange but I will wait for an alky kit or race gas before I ever open that valve again.

So the consensus is that there was no damage done to my GN as a result of this? As always thanks for your help.

 

[salvageV6]

6 I believe no problem, 12 might indicate some problems. It was a lot cooler last night though.

 

[blackbuick87]

Some cars can only tolerate 15psi. Mine can go 16psi, then I get knock. I hit 20psi with my Thrasher 100 and alky did not come on and it hit 11.5 or something, with a power plate. He is only running a street chip but its possible.

Your next purchase should probably be the RJC power plate, it will give you a little more safety margin