How do you think these plugs look?

[boosted79]

About 600 mi on them. BP8's, AFR 14.3 - 14.4 on cruise. Pretty good IMO. Maybe a little rich on a couple.

[T77911S]

if in order
#1 looks the best
2,5 and 6 look wet
3 and 4 look rich but I would not complain.

also depends on how long it idled before you shut the engine down.
I would try swapping injectors, 3 and 4 for 2 and 5 (or 5 and 6 (easier)).

check timing, might be a little advanced.

[boosted79]

That was after a few min. idle which is not a real good indicator. I was checking the valves so i thought I'd pull them to take a look. I'll do another check after I hold it at 2500 or so before SD. Maybe go to a BP9.

[mark houghton]

Originally Posted by boosted79

That was after a few min. idle which is not a real good indicator. I was checking the valves so i thought I'd pull them to take a look. I'll do another check after I hold it at 2500 or so before SD. Maybe go to a BP9.

If I recall, for NGK plugs BP9 is cooler than BP8. The lower the number the hotter the plug. Just saying...

[boosted79]

I'll have to check again w/o idling. MSD recommends starting with one heat range colder. I'm running leaner at cruise than idle.

[s5uewf]

On steady cruise other threads here have suggested we can run a little more lean. I am running about 13.8 idle, up to as lean as 15.5 cruise at low loads, lowering AFR to 13.2 just under the point where boost comes on, 13 at boost threshold, and then dropping quickly and getting richer down to 12.2 afr under full boost.

Adjusting AFR may be worth considering, if you have the ability to do this.

Every setup is different, though, so experiment to find what is safe for your engine.

[T77911S]

my first concern would be 2,5, and 6.
they look wet.
take look at the ground strap on 6, it looks wet. should look more like #1.
check timing.

swap injectors before making adjustments.
then I would swap ports on the FD.

[boosted79]

"then I would swap ports on the FD. "

Do you mean change the line to a different port? Why not adjust that port at the FD? Timing is still stock at 5 ATDC at 1k rpm. I will bump that to 10 BTDC or so once I get the dizzy locked and set up a curve in the MSD.

[T77911S]

NO!

don't adjust the FD until that is a very last resort and you are willing to send it off to be rebuilt if you screw it up.

swap injectors first. swap 3 and 4 for 5 and 6.
then swap the lines at the FD for 4 nd 5 if you can. don't screw up (bend) the lines if that's the only way to do it.
are 2,5,6 wet or do they just look wet.
is it fuel making them wet

check intake bolts for air leaks

I am thinking about getting one of those colortune tools to see what each cylinder is doing.

[boosted79]

I rebuilt it and set all of the flow volumes with a scale, see below. I set 2 and 5 4% rich because they get more air with the pancake manifold, I have no problem adjusting the FD if necessary. But like I said reading the plugs at idle is not really a good indicator because you don't run the car there.

[T77911S]

that's a pretty fancy chart.

when I tested my FD I timed the flow tests for constancy of volume.

kind of why I am thinking about getting a colortune.
everyone talks about 2 and 5 but it might be nice actually measure or see the mixture.
not sure if you would notice anything at idle or if you would see a difference if you revd it up.
just something to play with.

[boosted79]

I think I am going to put new injectors in it, they have 80k miles on them and I did the cleaning thing and they "looked" ok but not perfect. Or maybe take these to a bosch shop and have them tested and see what they say. Then I'll have to go thru the whole flow balancing thing again. I think I need a new accumulator also, what's a another grand? These cars are like BOATS, Break Out Another Thou.

[patina]

Originally Posted by boosted79

I think I am going to put new injectors in it, they have 80k miles on them and I did the cleaning thing and they "looked" ok but not perfect. Or maybe take these to a bosch shop and have them tested and see what they say. Then I'll have to go thru the whole flow balancing thing again. I think I need a new accumulator also, what's a another grand? These cars are like BOATS, Break Out Another Thou.

For what it's worth Race City Injector out of Mooresville, NC does an excellent job ultrasonic cleaning and flow testing the injectors. Very quick turn-around and very reasonable pricing. Chad has done 10+ sets for me personally.

Fuel Injector Cleaning Service | Race City Injector

[T77911S]

save some money and just do some tests. swap injectors at the least, then have them tested if the problem moves. also pull the injectors and see if they leak.
the plugs are not that big deal.
why the accumulator?
open the bottom fitting, if fuel leaks out it may have a hole In it. (the return line).
i have never run the pumps with this off. i have heard you can for the 911 but you may want to plug the return line. there is no "pressure" other than resistance from the line and the fuel in the tank. i would only do it if fuel comes out the acc,.

[boosted79]

I'll do some tests first, thanks for the lead on the injector shop. It's either accumulator or pump check valves because it has the hot start problem. I have my cold start valve on a push button and when I give it a few shots when warm it takes off so I'm thinking vapor lock.

[1979-930]

Originally Posted by boosted79

I think I am going to put new injectors in it, they have 80k miles on them and I did the cleaning thing and they "looked" ok but not perfect. Or maybe take these to a bosch shop and have them tested and see what they say. Then I'll have to go thru the whole flow balancing thing again. I think I need a new accumulator also, what's a another grand? These cars are like BOATS, Break Out Another Thou.

This. They are 38 year old 80,000 mile injectors. My car runs fine, but when I install the new exhaust and turbo this winter new injectors are going in.

When I worked at a diesel shop, 20 years ago, serviceable injectors needed to be adjusted every 30,000 miles on trucks a year or so old. Added shims and new tips were the norm. The injectors ability to hold pressure on ours is diminished. And I'm sure the spray pattern is bad.

Think of it this way. A mechanical injector is only as good as the pressure it can hold before firing and the cleanliness of the tip. If the injector starts bleeding off fuel or fires before peak pressure is achieved then the atomization of the fuel is diminished. Same with a dirty tip. Poor atomization and burn.

[boosted79]

x2. I think I'm going to stick one of these on and get rid of the CIS.

[1979-930]

^^^ Ha. You have enough projects...
I would love to have an old bench top pop tester to see where mine are opening at. It's supposed to be 3.0 bar from what I can find.

[boosted79]

I checked out that Race City injector service. Looks like they specialize in EFI injectors. They say they don't do diesel injectors which essentially what these CIS ones are, just a much lower pop pressure.