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No power after head gasket repair?

  • Thread starter Thread starter Desert Stallion
  • Start date Start date May 28, 2004

Desert Stallion

Founding Member
Aug 5, 2001
651
0
16
Queen Creek, AZ
May 28, 2004
#1
  • May 28, 2004
  • #1
Here's the deal... Car was originally a blower car, had AFR 185 heads, TFS Track Heat intake, blower cam, 24lbs injectors, 190lph pump, 75mm TB/EGR spacer and 80mm MAF calibrated for the injectors. Stock computer. Bought car with blown head gaskets, but it ran strong and had good driveability for the 1/8 mile test drive and going up and down my driveway a couple times. Took the car down for a week to do the repair, removed the blower but left the rest of the car as it was. Heads, cam, intake, TB, MAF, injectors, etc are all the same components.

Car started right up on the first try after the repair, and outside of needing to readjust the rockers and an exhaust leak all seemed well. Adjusted the rockers, fixed the leaking passenger side header gasket, set the timing at 14* and off we went for a test drive.

Well, the thing is gutless. Truely, truely gutless. I figured that it was the computer trying to relearn everything and to give it a day or two of driving. Meantime I took it through emissions, and with the help of some denatured alchy and a pulled injector it passed with flying colors. And I mean flying colors.

Plugged the injector back in and drove her home. I've put a dozen or so miles on it since then, all testing this and that, and I tried to run it up the RPM's today to about 4-4500 or so, and it feels like my dad's 6-banger F150 with 3.08's out back. Well, not that bad, but close enough for you to get the idea. I had a stock '90 GT that would walk all over this car right now. There's just no power. You mash the throttle, and the RPM's slooowly climb up there, and it sounds perty good, but there's no pull.

It idles fine, and seems to walk off the line okay for having such big heads in a N/A setup.

Here's what I'm thinking... Enormous vacuum leak, which my vac guage doesn't support as it seems to have good vac at idle and cruise. The car's still running uber rich, which is possible with the 24's in place. It took 2 tries to beat emissions, the first was my baseline with everything in street trim and only the alchy being different and the car was pig rich.

I don't know why it would be, but I'm open to any possibilities right now. Next, TFI is dying and I'm not getting any timing advance. Could be I guess, but I'd think I'd still have a little better performance than this.

I don't have any dragging brakes. I can push the clutch in while cruising and it'll hold it's speed without being dragged down.

Could it be that the computer just hasn't learned yet? It's started and stopped at least a dozen times between my garage and my short little test drives, so I'd think the computer would have some sort of baseline.

What about having the alchy still in the tank? Could that be hampering performance, like causing the computer to pull timing because of a knock sensor or something?

Thanks for y'alls help.
 

cardudeusa

Founding Member
Oct 22, 2002
1,744
5
48
Home of the Florida Gators!
May 28, 2004
#2
  • May 28, 2004
  • #2
Sounds to me like the timing is wrong. These cars don't have knock sensors so thats not your problem.
 

Desert Stallion

Founding Member
Aug 5, 2001
651
0
16
Queen Creek, AZ
May 28, 2004
#3
  • May 28, 2004
  • #3
"Like the timing is wrong..." If by that you mean that the distributor is off a tooth or whatever, that's very unlikely. I put the distributor back in according to the marks I made beforehand, and with the SPOUT removed set the timing. The car idled with the SPOUT removed just fine at 14*.

I don't know, if it was off enough to cause a symptom like this I'd expect serious idle issues.
 

cardudeusa

Founding Member
Oct 22, 2002
1,744
5
48
Home of the Florida Gators!
May 28, 2004
#4
  • May 28, 2004
  • #4
I dunno how possible or not it is in you're case. But thats what it sounds like as far as symptoms. I've never heard of alchy so I cant give advice there.
 

Desert Stallion

Founding Member
Aug 5, 2001
651
0
16
Queen Creek, AZ
May 28, 2004
#5
  • May 28, 2004
  • #5
'Alchy' is my short/slang term for denatured alchohol. Burns clean and helps put a car through emissions.
 

cardudeusa

Founding Member
Oct 22, 2002
1,744
5
48
Home of the Florida Gators!
May 28, 2004
#6
  • May 28, 2004
  • #6
Oh, ok so was the car feeling sluggish before you put that in? I'm glad I don't have to worry about emissions.
 
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