1991 RS 305

The topic of spark plugs, like most everything car related, seems very controversal. Why, aside from higher cost, does most everyone HATE Bosch 4's? I've used them before, and thought they ran/fired great. In a car like our 3rd gens, a plug like this makes sense, since a plug change can be a little tight at times. Does anyone have any hard, cold facts/eveidence that these are, in fact, a bad plug choice, and they REDUCE performance? I'm aware that Delcos seem to be the plug of choice on this board, but does it stand to reason that a company like Bosch, that makes quality injectors, oxygen sensors, etc, the very brands that come in our 3rd gens stock, would use inferior spark plug technology/engineering, just for the heck of it? Comments, please

onebad82z

iTrader: (7)

That is the plugs i run in my 2000 S10 and love them..have 0 complaints.Been in the truck since it hit 25,000...I have 63,000 miles as of today and still runs perfect.I would run them in my Z but can't because I spray often and as we all know platinum tips and juice are a no no.Yes they are expensive but I feel they are a top quality plug.Only way you are gonna know if they work for you and your car or not is to try them.

SpeedJunkie

Yup, I have em in my car. Works great, even though i cant tell the difference. Havenmt had a fouled plug yet. I have em in my plowtruck in the sig too. Just the one tip ones though. That thing barely sees over 45mph and i still have yet to foul a plug or a need to replace them. Both vehicles are fuel injected but i think theyre great, no problems here

N8Miller

kind of off topic...but why cant you run nitrous and platinum plugs?

I had Bosch in my old TA,....worked great

Gunny Highway

iTrader: (1)

For the money, I wasn't impressed with them in my Caprice (305 TBI). Also, my friend had them in his 97 T-Bird (4.6L); and he blew the plug clean out of the engine driving home one night. He replaced it with your standard Ford Motorsport plugs and has been fine ever since.

86BirdSE

I installed the platnium 2's, 2 electrode, not 4, and I have no problems at all. I've installed the regular platniums in 3 other SBC applications (2 trucks, one carbed and one fuel injected) and an EFI van. I feel no difference in the regular platniums and the 2's., and have not seen any fouling and whatnot like other people report

Oh, Geez, I forgot I have Accel Super Stock spiral wires on my car too, and a dynomax cat back... not AC Delcos, MSD's and Flowmaster like the rest of the herd here have. Guess it makes me a lala.:lala:

I feel my car runs great, and it gets about 18-20 MPG on 93 Octane gas with fairly aggressive stop/go as well as some backroads driving.

I can't decide for you of course, but I have no problems with the stuff other people are so quick to blast with stories like "My friend blew one out the passenger door" and "my uncle one night after a six pack of Bud had one shoot right through the hood when he was racing a Viper RTS." I just prefer to use my own experience when giving a reccomendation.

MdFormula350

https://www.thirdgen.org/techbb2/sho...=bosch+nitrous

chevy8ford

I think that the price argument is basically the only one. Why spend 6 dollars or more for a plug, when the 99cent acdelcos are what the ignition companies tend to recommend. They say that there is no difference in teh type of plug, and usually warn agains platinum. Also the fact that platinum doesn't actually conduct better than regular copper, it just has better anti fouling properties. The idea behind the 4 plugs is a gimmick, it is so they can charge you more money for "new technology" IMHO, i don't see the point of spending more money on the 4's if i don't have to, anyhow, although sparkplugs are a necessary component, they aren't gonna win a race for you, i.e. if my friend has 4's and i have delcos if either of us win it isn't gonna be cus of the sparkplugs. THink about it, most people know about sparkplugs and oil filters, so where do most of the gimmicks turn up? these two places. I'm not saying 4's suck and i dont' think anyone has hard data that they are better or worse, but just from a fiscal standpoint and common sense, there are better things to waste money on. In fact, plug gap would have a greater effect on performance than plug brand.

just my .02

Mike

Fredless

My car was rough idling, pretty bad at stop lights and especially when it was hot(some damn reason the car idles harder when it hits 220 and above, rarely that high of temp). So, just for the sake I had gotten paid, didn't want to gap the plugs exactly and I was extremely happy with the +4's in my Intrepid R/T I bought them. 50 bucks total with tax, but for 300-400 miles or so, the car idled smooth as my dodge did. Now, it's beginning to idle hard again, but not nearly as hard as it did before when 4 of my 8 plugs were fouled badly. I guess my wires need to be replaced with MSD or something. So in answer, I noticed a big difference over my old bosch platinum regulars in performance, starting and idling. But you should notice all of the above with fresh plugs vs old fouled ones.

firechicken305

ever heard of sidegapping a sparkplug? platnum i can't comment on (never used it) but the 4 prong idea is BS. Maybe in a Hemi, complete BS in a SBC. The only thing ignition is generally good for is throttle responce anyway, unless you running enough fuel through there that the stock ignition wasn't enough. As far as horsepower, it's only a dyno difference.... good for trailer queens and ricers. take my drag quad for example, i went from 282cc to 410cc (stroker), from 9.5:1 compression to 12.5:1, it's got a monsterous cam, and a carb big enough to feed it. stock ignition is fine for that bad a motor. It's all in the quality of the gas. i run strait race gas in it. Unless you are running into problems with the fuel not completely igniting in the first place, ignition doesn't create horsepower. Therefore on your stock SBC, it's basically a drivers preference mod. It only serves to make the stock motor more responsive.