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chuckfryer
02-02-2006, 04:09 AM
I've recently upgraded to 50# injectors with an appropriate chip. Can anyone help me with an appropriate static (i.e., vacuum line removed from adjustable fuel pressure regulator) starting point? With my old injectors, I started with static 43#. I've adjusted to 53# static, with only 15# boost, but I'm still getting over 8 degrees retard (on a Scanmaster) at half throttle. Having blown a head gasket recently, I'm nervous about pushing much more. Here's my setup: Stock 3.8 ltr, TE44 turbo, Champion iron heads and intake manifold, 65mm intake, cold air intake system, Poston headers, Terry Houston 3 1/2 downpipe, 2 1/2 crosspipe, alloy pistons, chrome rings, everything ported and polished, etc. (meaining: all the other standard mods). Help!!!!!

87geeinn
02-02-2006, 10:11 AM
Dude, that's WAY to much. You might be gettting rich knock. Whoever did your chip should have told you what baseline pressure to start with (e.g.-TurboTweak chips are usually set at 43psi for most injectors). It seems as though you know this already judging by your post though. I'm assuming with all that new engine work, you've got new plugs, wires, ig. mod., and coil pack right? Checked connections at coil pack and plugs? These are newby suggestions, but I would suggest starting there if you haven't done so alreay. I'm sure the pros will be able to help if none of the above is the problem. Good luck.

JHensberry
02-04-2006, 12:49 AM
Do you have the right chip for your injectors? 43# static is a good baseling to tune from. You need to try to start alittle lower/leaner to make power and then move up in most cases. A 44 is a good midrange turbo. Do you have a test N tune gauge to see if your fuel is doing what it is supposed to do? Do you have weak motor mounts, getting false knock?. I would be concerned with your set up and getting 8 degrees at only half throttle. Second, all the work on the motor and bolt on, don't really consider that a "Stock 3.8 ltr"

kenmosher
02-04-2006, 11:29 AM
The 50s don't like a lot of fuel pressure ... they are "ball" design injectors and tend to get erratic and lock up if the pressure is too high.

They are also notoriously inconsistent in flow between injectors when they approach this condition. It might be possible you have an injector that is out of balance or lazy.

They should provide MORE than enough for that TA49 turbo at lower fuel pressures.

PaCemkr86
02-04-2006, 11:30 AM
The 50s don't like a lot of fuel pressure ... they are "ball" design injectors and tend to get erratic and lock up if the pressure is too high.

They are also notoriously inconsistent in flow between injectors when they approach this condition. It might be possible you have an injector that is out of balance or lazy.
your exactly right Ken, been there , upgraded to the motorons 60#'s

chuckfryer
02-08-2006, 03:50 AM
Hey guys, thanks for your responses.

My sad story is that I've rebuilt this engine 4 times in three years. Wiped a cam, spun a cam bearing, blew a head gasket, wiped a cam.

Most recent rebuild was by a Turbo Buick "guru" in my vicinity. Lasted 430 miles before it wiped a cam again.

But during those 430 miles, I had no knock issues. So I believe the 50# injectors and the new chip were O.K. Since the most recent go-round, I've got this knock issue.

Could it be a timing problem? Cam sensor setting issue? I backed the fuel pressure down to 43# static and still have the problem. Damn! I didn't buy this thing so I couldn't put my foot in it!

Keller
02-08-2006, 10:10 AM
You may just have a bad injector. Have they been flow-tested off the car?

Your knock may not be in the engine. Something outside the engine may be hitting and fooling the sensor.

With all you have on it, it sounds like this motor is built for much more than a TE44 in the long run.

chuckfryer
02-09-2006, 08:16 PM
If it is "false" knock due to vibration, wouldn't I expect to see it when the engine is revved in neutral? (I don't.) Anyway, I'll poke around to see if something else is vibrating and fooling the sensor. BTW, the knock readings I'm getting seem to be pretty constant and wholly independent of fuel pressure settings.

chuckfryer
02-10-2006, 01:55 AM
As my college frat brother used to say: "and furthermore" . . .

Is there some other means by which we can distinguish between real and false knock? Are we forever tied to GM's knock sensor? In reviewing several posts going way back on this website, this seems to be a continuing issue. Many threads just seem to die without a report of successfully beating the problem.

chrisgarrett
02-10-2006, 08:12 AM
Start here: http://www.turbobuicks.com/forums/showthread.php?t=36770

gnxtra
02-10-2006, 08:17 PM
I have 50 # and run 38 to 42 static. Works fine for me. :pat: