Performance 101
#17
Looks like you covered a lot of the maintenance--but you didn't change the fuel filter(?) For $35 you could get a fuel pressure gauage on your fuel rail; at least you'd know if you're getting good pressure. And it'll help not only now, but in the future.
I also agree with setting it back to normal timing--at least 'til you figure it out. And while you got the timing light out, I'd clamp it to each of the sparkplug wires just to make sure you're getting a steady pulse and that it's not eratic spark. Mine had that--replacing the green wire that fixed that.
Good luck! / Bruce
I also agree with setting it back to normal timing--at least 'til you figure it out. And while you got the timing light out, I'd clamp it to each of the sparkplug wires just to make sure you're getting a steady pulse and that it's not eratic spark. Mine had that--replacing the green wire that fixed that.
Good luck! / Bruce
#18
I don't think anyone has mentioned this yet, but you might want to double-check the cam timing belt is lined up correctly. If the belt has jumped a tooth, it can lose a bunch of torque, which may be why advancing the timing helped a bit.
HTH,
-don
HTH,
-don
#19
having as many dyno runs on an 84, with more mods from stock to 5 liter part euro, I can say that you just have to climb the bolt-on tree!.
headers/exhaust
dont worry about the timing, only 3hp either way there. (and ft-lbs of max torque to trade with0
KN filter
when you want to really start pumping up the HP, get a euro intake system. (bolt on, but kind of rare)
Dont forget the euro cams (also bolt on, but a pain to install)
after all this, you might go from 175rwhp, to near 240rwhp.
Dont forget to upgrade suspension, and maybe lowering the car and put on some larger tires.
headers/exhaust
dont worry about the timing, only 3hp either way there. (and ft-lbs of max torque to trade with0
KN filter
when you want to really start pumping up the HP, get a euro intake system. (bolt on, but kind of rare)
Dont forget the euro cams (also bolt on, but a pain to install)
after all this, you might go from 175rwhp, to near 240rwhp.
Dont forget to upgrade suspension, and maybe lowering the car and put on some larger tires.
#20
My red '81 was purchased as a parts car, but I ended up getting it running instead because it was so easy. Part of the rear quarter was burned on the paint and the corner of the bumper melted like the muffler had been on fire. Someone (apparently) had tuned it up, washed the motor, etc. and had the car start misfiring and kept driving that way until the exhaust became fuel laden enough to expel hot enough air (or fire?) to burn the rear of the car. When I got it running it was completely gutless and I could hear the big throaty sound in the intake like a clogged cat makes. Next stop...bypass the cat. Still nothing. I finally discovered the double wall pipe in the Y section at the front had the inner layer get hot enough to expand shut inside and nearly completely stop exhaust flow from the right bank. Anyway, that's a long shot but if it sounds real throaty on acceleration you might wanna check. Good luck.
#22
Yes, this does somewhat make up for the known AT issue, though she is still a pig on her way up.
On entropy's point, I know the exhaust is clear, as it is new including the Y pipe back and the issues pre-date that mod... However, there is a very noticable "sucking" or "hissing" sound on acceleration that gets louder with RPM... anyone think this is relevant?
Thanks for all the great info, this is very helpful!
rob
On entropy's point, I know the exhaust is clear, as it is new including the Y pipe back and the issues pre-date that mod... However, there is a very noticable "sucking" or "hissing" sound on acceleration that gets louder with RPM... anyone think this is relevant?
Thanks for all the great info, this is very helpful!
rob
#24
I did not check the cable personally, though I asked my mechanic to check this and he tells me it is tight and has no slack, that said, I will again check it myslf when the snow clears. At this point I am thinking the AT issue is vacuum related. On the intake boots, they seem strong, however I am planning a spring project to remove, inspect and clean the intakes.
#28
I agree; one of the starting points is to check out all the vacuum lines. That said, does anyone know where I can pick up the vacuum diagram and pressure specs for the L-Jet? I have a limited version of the shop manuals on CD though it does not seem to include this data.
thanks.
rob
thanks.
rob
#29
One of the best places is under the hood on the emissions sticker. Makes it hard to see which line goes where on the throttle body, though. I think the 84 owners manual might also have the diagram.