Engine performance degrades quickly

...Check Your #1 Cylinder TDC to the Zero 'Mark' on the Damper Balancer! There may have been slippage there causing an inaccurate Timing Setting.
Also sounds like a Streched or Warn Timing Chain, can be checked by observing with a Timing Light.

Could be a Vacumn Leak or Carburater Problems.

Why 'It' would run well, and then run poor; may be hard to find! Are You running a 'Points' Distributer? If so, the Dwell Setting may be Off, affecting Timing!

Last, check ALL the Plug Wires CAREFULLY for Grounding or Shorting Out Between Each Other, Especially at Higher Revs. Look for Arcing At The Distributer CAP, Near the Headers and Stainless Braided Hoses! A good way to check this, is at Night with All the Lights off, with a Second person revving the Engine while You Observe the Engine Bay. And Be Sure to keep the #5 and #6 wires completely Separate/Insulated to Prevent Cross-Fireing!

I would also check the Inside and Outside of the Distr. Cap and Rotor, for 'Carbon Tracking'!

A Lot of things can cause poor running. It could be as simple as the Wrong Spark Plugs or just the Wrong Gap!...

Good-Luck!

I had a vacume leak and thought it was a burnt valve... Took me to school! I finally resolved it and the car is running good. Use a butane torch ( Don't light it } and wave it slowly around the carb/intake to indicate a vacume leak

quote:

Originally posted by PLT-1:
I had a vacume leak and thought it was a burnt valve... Took me to school! I finally resolved it and the car is running good. Use a butane torch ( Don't light it } and wave it slowly around the carb/intake to indicate a vacume leak

I just use starter fluid. Same result.

Thanks Guys, Jack , we checked several things You said, but I am no great light on elektrical things What puzzeld me is why it worked fine again after I changed the plugs and did nothing else, and then got worse again.

#1154

> What puzzeld me is why it worked fine again after I changed the plugs and did
> nothing else, and then got worse again.

If you have a weak spark and/or a rich mixture, new plugs will work for a while
until they get fouled. You can pull a pulg and check it for fouling and can
check spark strength with a tester. The tester will snap in place of a spark
plug and have a grounding clamp. Some have a glass tube, others are open
with an adjustable gap.

Dan Jones

1154 is an early high compression motor. I had same problem... I changed all the distributer and wires. WHAT solved it was a set of new plugs with a wider gap MSD 7al liked .048 to .050 gap.

a lot has been done by a swedisch guy a lot of yaers ago, the car has apeared in a magazine in swedisch witch I dont now so here go's: originalblock och vevaxel svo aluminumtoppar, competion cams varsta hydraulkam crane cam lytare manley rostfria ventioler, svo hoge insug, modiferad holly 650 dp, trw hogkompressionskolvar, kn 9' gary halls 180 headers, some words are easy others not. THe engine , according paperwork gives 458 horses. I have replaced the platinum sparks. The dizzy works with a light beam and is new, and yes a put in fuel, witch it takes a lot of 30 liters more or less, seeing the fuel tank is up front and takes only 45 liters , i am driving from one to the other . the car weighs nearly 200 kg less than standard, so accelleration is pretty good, if it works

Some more info, i have a promaster mallory coil, msd 6al ignition, mallory distributor and sparks are ngk bcp6evx gap is 0.30, to small maybe?

For your reference.

Plugs currently in mine do have a 0,95mm (0.037inch) gap, the new Autolite's I have on the shelf a 0,85mm (0.033inch) gap.

The one and only time I checked my fuel consumption, I had a 18,8L/100km.

Thanks guys for all the advice, been working all day on the cat, set the sparks to 0.40. Nothing changed, then it turned out the guy that worked with me on the car did forget to tighten the distributor. So I am a happy trooper first for fixing the problem en second for not doing such a boobo

Time for a test drive

I had a similar problem with my ignition. It wouldn't crop up until I drove it at freeway speeds (on the freeway ofcourse)for 5 to 10 miles then exit. It would idle like crap afterwards and sound like a VW bug when I try to accelerate. It ended up being the MSD box.

BTW.... for tuning, look up the specs for the MSD 6AL for the recommended gap for your application.

thanks, by the way for those thinking about 180 headers changing spark plugs is a f...... pain in the a..

Challenges with spark plug change depends on the tube layout of the 180s. My plugs are easily removed.

I have yet to learn who manufactured my 180s. Although, they appear to be a custom build in the 90s by a resource of Glenn Pascal, a Pantera restorer in Pennsylvania who passed several years back.

I have presently began a cosmetic freshening up of my GT5 and will shift the heat shield to the decklid a part of the process. I prefer exposing the 180s when the decklid is lifted.

Today it was my turn - had to turn back home because of a bad running engine - and only then I found out I left my house keys in the garage (the one of the garage included)...duh...

Had no time yet to figure out wat is wrong with the cat.

quote:

Originally posted by suburb:
thanks, by the way for those thinking about 180 headers changing spark plugs is a f...... pain in the a..

So is setting valve lash hot!

> I have replaced the platinum sparks.

Did you replace them with platinum? Platinum plugs are more susceptible to fouling by rich mixture. They seem to work fine on EFI engines but on carb engines that run rich (with the choke on, or at WOT) they can foul easily.

Dan Jones

Hello Dan, You could be right on that, but I think the way You drive can have also something to do with fouling, such as low revs a lot of the time,thanks for Your input


#1154