I want to know which plugs are best for '88 4&6 cyl. engines.
Thanks

Safe response is AD Delco factory specs.

There are silver core and platinum, but there is alot of debate about if they are worth the effort and additional cost.

If you are hopping up the engine at all, cold range are better than hot.

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Arn Brown,

I use AC Delco Rapid fires. NGK UR5's are also good. 1FST2M6 dyno'd the NGK's and could actually see a gain. These are for the V-6. As for the 4-cyl, Stay with stock, The DIS system doesn't like some plugs. I know the Bosch Platnums don't work well with the 2.5L DIS system.

Dittos on A/C Delco or NGK UR5. Personally I haven't had much success with Rapidfires, they've had issues in the few vehicles I tried them on. Unless vehicle is modified, stick with stock plug.

NGK UR5. they are the best with the V6.

Champion's cracked and blew out of the heads several times. Never use those.

I agree with the ngk UR5 I haven't had anyproblems with mine.

NGK UR5 on the V6. Not sure about the L4.
The UR5 made a noticeable difference in how smooth my engine ran as compared to good condition AC Delco plugs.

The last plugs I bought were the Bosch Platinums +4's. I didn't really notice a diffrence in gas milage, or performance though. Has anybody else tried these plugs?

quote Originally posted by Deabionni: The last plugs I bought were the Bosch Platinums +4's. I didn't really notice a diffrence in gas milage, or performance though. Has anybody else tried these plugs?

From what ive heard about those they are nothing more than a waste of money... it might increase your compression by about .000000001 because of more metal?

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'86 Fiero GT

www.KylesFiero.tk
www.XoticRydz.tk

Multi tip plugs are just a gimick. Stick with any plug that has just one electrode. The spark will only go across one gap anyway. I do use Bosch single tip Platinums in all my cars with no problems. Usually good for 40-50K. Ones out of a Lincoln Town Car I had, were in for 170K and still looked fine. I have heard they dont work well with DIS ignition though.

I prefer Champion.

Spark plugs

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My Web page

I use AC regular or Rapid Fire. No problems. When I had an '86 2M4 (non dis ignition) I had problems with Bosch Platinum plugs. Missing under load! Shi* plugs!

Whats the proper gap for the V6?

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1986 Fiero SE

I prefer plain old A/C DELCO for most applications until you get to really high performance situations, then Bosch

Phil

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87 FIERO GT 2.8 5spd

GM auto tech for 27 years. Specializing in electrical and computer problems. Now on workers comp. and it looks like I will be unable to return to work as a tech.

not to hijack this thread but since were on this spark plug topic and i was going to do a major tuneup next week i wondered if 6.50 a plug for the ngk iriduim is reasonable. This was on the internet that i got this cost.

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fast and reckless

AC Delco.

Delco!!

for all of us old timers here, run dog run,put your tail between your legs and hide....

One more vote for AC Delco

I used Platinum on all mine like I said. I tried the AC Delcos last change for the hell of it. They started misfiring in less than 10K miles. Put my Platinum back in.........

quote Originally posted by doublec4: Whats the proper gap for the V6?

Gap = 45.

I like Accel plugs myself. I've tried NGK's, stock delcos, rapidfires, and platinums but none of them ran as well as the Accel U-grooves do. They feel new for a long period of time where as the others seem to wear in after a while.

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Activities Director N.I.F.E.

www.fierofocus.com

This forum is becomming sooooooooo civalized! This topic was a major flame war a coupla years back.

Delco here. I also like Bosh Platinums, single electrode. I first used them in my VW's. I put a set of the Bosch 2 electrode tips in a T-Bird and they missed until I replaced them with Autolites. That was the end of multi-tip sparkplugs for me.

Ducks and runs for cover...

quote Originally posted by webbee: This forum is becomming sooooooooo civalized!

Too late... you jinxed it...

I stay with regular AC delco plugs... I've heard some bad things about platinum's - and have you seen the size of their tips!?! They look like they'd erode in 10 miles they're so thin.

You dont have to gap Platinums, and like I said, even though the tip may be small it does last. I put my original Bosch in Ferraro when it was done. Used them till 75,000 miles. They still looked fine, but I tried Delcos. They started misfiring within a month or 2. Ones i took out of my old Lincoln at 170,000 miles (limo, lots of idleing) looked good enough to go another 100,000. Thats my story and Im sticking to it........

what about those splitfires that the fiero store advertises? do they suck or something?

YES, as does any other multi tip plug. Spark only goes across the closest one, the others just set there. $6.00 each verses $1.50 each too,

So what plugs would you guys recomend for an MSD Ignition System, not just the coil. I have the MSD 6AL Box, MSD Superconductor 50ohm per foot wires and an MSD Blaster Coil. Oh and I do use the occasional Nitrous shot during the summer months. I had AC Delco plugs and fried em in about 3000 miles. I have heard bad things about MSD and platnium tipped plugs.
These UR5 plugs are they colder or hotter than the stock plug.

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85GT 2.9 4spd MSD Everything, Big Cam and Nitrous. www.captfiero.com

quote Originally posted by Capt Fiero: So what plugs would you guys recomend for an MSD Ignition System, not just the coil. I have the MSD 6AL Box, MSD Superconductor 50ohm per foot wires and an MSD Blaster Coil. Oh and I do use the occasional Nitrous shot during the summer months. I had AC Delco plugs and fried em in about 3000 miles. I have heard bad things about MSD and platnium tipped plugs. These UR5 plugs are they colder or hotter than the stock plug.

i had the same problems with all my msd and the rest of the high perf. electric system . i burned through 3 sets of plugs , untill i tryed accel shorty header plugs . havent had a problem since

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86 and 87 fiero database www.geocities.com/cwandall/fiero.html

quote Originally posted by Oreif: I use AC Delco Rapid fires. NGK UR5's are also good. 1FST2M6 dyno'd the NGK's and could actually see a gain. These are for the V-6. As for the 4-cyl, Stay with stock, The DIS system doesn't like some plugs. I know the Bosch Platnums don't work well with the 2.5L DIS system.

Exactly what he said.

Multitips plugs arnt bad, there just not worth the money. the spark will jump to the easiest path (most of the energy, but some will go to the other) But if one gets dirty or something, the other one is usually still there to take the spark. I have platinums in my 86 v6 and im gonna go to ac delcos, I dont like them, but thats personal preference.

quote Originally posted by Dave Gunsul: Gap = 45.

I love this place!
Just turned on the 'puter and did a search on "plug+gap".

Saved me from running upstairs and digging out the owners manual. (Strangely enough it's not in the shop manual.)

Thanks!

[EDIT] Sorry... One more vote for NGK UR5s.
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Raydar
88 3.4 coupe...........

Coming soon...
88 Formula, presently under the knife.

[This message has been edited by Raydar (edited 04-04-2004).]

If I get rid of the comments which don't specifically identify a plug preference, the score is-
AC - 10; NGK - 7; Bosch - 2; Accel-1. So far most of the guys prefer the original AC which was the R42TS. Ed

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Here's my stock A/C plugs at 35k miles:

Basically any plug will work fine on the stock ignition system. The platinum plugs don't work on the DIS cars because it's a waste spark system that jumps the spark backwards on two of the plugs and that cause rapid failure.

JazzMan

quote Originally posted by JazzMan: Here's my stock A/C plugs at 35k miles: JazzMan

Those look better than my first set of Champions after 35 miles!