Spark Plugs
 

I have a 1991 GTA with the 350 TPI. The car has 109,xxx on the clock and I want to change the spark plugs considering I have no idea when they were last done. The car is bone stock except for an SLP Loudmouth 2 exhaust. Which plugs should I get? As a reference, this is a weekend car, I don't beat on it and it is driven less than 7500 miles per year. Also, I am running manifolds with that A.I.R. crap so I don't wanna have to worry about these things.

50-R5724-8 NGK Racing R5724-8 Spark Plugs, three heat ranges colder than stock, gapped at .032 $2.25 Buy Wish


50-R5724-9 NGK Racing R5724-9 Spark Plugs, four heat ranges colder than stock, gapped at .036 $2.25 Buy Wish


50-TR5 NGK TR5 Spark Plugs, Stock heat range, gapped at .035 $2.25 Buy Wish


50-TR55 NGK TR55 Spark Plugs, Stock heat range, gapped at .050 $2.25 Buy Wish


50-TR55-IX NGK TR55-IX Iridium Spark Plugs, Stock heat range, gapped at .050 $6.99 Buy Wish


50-TR6 NGK TR6 Spark Plugs, One heat range colder than stock, gapped at .035 (Works well in Nitrous, Supercharger, or High-compression motors) $2.25 Buy Wish


50-UR4 NGK UR4 Spark Plugs, Stock heat range, gapped at .035 $2.25 Buy Wish


50-UR4-IX NGK UR4-IX Irrdium Spark Plugs, Stock heat range, gapped at .035 $6.00 Buy Wish


50-UR5 NGK UR5 Spark Plugs, Stock heat range, gapped at .045 $2.25 Buy Wish


50-UR5-IX NGK UR5-IX Irridium Spark Plugs, Stock heat range, gapped at .045 $6.99 Buy Wish


50-FR4 NGK FR4 Spark Plugs, Stock heat range, gapped at .035 $2.25 Buy Wish


50-TR6-IX NGK TR6-IX Iridium Spark Plugs, One heat range colder than stock, gapped at .035 (Works well in extreme conditions, such as Nitrous, Supercharger, or High-compression motors)

Thanks!

I would say to just go to the parts store and grab stock heat range AC Delco's. No need for anything fancy.

- Justin

Yes, why change heat ranges? I've had good success with NGKs in the past as well.

I was told I should run these:

50-UR4-IX NGK UR4-IX Irrdium Spark Plugs, Stock heat range, gapped at .035 $6.00 Buy Wish

They are the iridium ones so they are good for 100K under normal driving conditions. I have a few weeks before it starts to warm up for me to do this so I'll keep researching.

You guys have any expierience with the fire sleeves? Since I am sticking with the manifolds I heard these are a good idea as well.

Thanks

in that motor iridium is about as worthless as **** on a bull...$1.48 autolites will run better...and if you don't like autolite get delco...no ngk...

Why won't they run well? I thought NGK's were the best?

the brand and style of plug does not make a dramatic difference in performance unless there is something else in play to effect the spark efficiancy. if you did a major upfit on your ignition, like to a 16volt system, or had boost/spray going through it, then you would have conditions that coudl show a difference between styles and brands.
if you jsut want to do a tune up, get the regular ac delco/autolite plugs from the parts store.

we used to stock autolite plugs. autolite ftl

either get the normal crap or tr55's

Regular heat range, stock plugs. Either Delco or Autolite.

For a stock engine I would just get stock plugs. Personally I like NGK, but for such a mild engine it won't make much difference.

I run delcos in the older motors, aluminum lsx motors i run ngk's and vortecs i run the 5buck delco plugs.

Thanks for all the replys guys. It looks like I will not be going after the iridium plugs. I guess I will just go with the delcos.

Thanks!