I was lookin for better spark plugs and i heard the best ones out there are PLATINUM +4... instead of having one (or 2) ground electrodes, Bosch Plat. +4 has 4 of them.. which suppose to make a more powerful spark, meaning. better fuel, acceleration yatta yatta whatever.

They dont have one exactly for the tC yet but they have one for the 4cyl. Camry (exact engine model). I spoke to the dudes at Autozone about the platinum4 plugs for my tc and they said it will fit the tC since both engines are exactly the same. ( he felt confident when he said that)


im still not sure if i should install it. You guys think its ok to change the spark plugs to with bosch plat. 4 eventho the plugs are for camry models? what you guys think?

 

a pic of what it looks like

 

I wouldn't change your sparks plug because the tc already has some nice ones. The tC comes with denso iridium which in my opinion will outlast the the bosch platinum, plus denso is made for imports and the only other spark plugs I would use is ngk. But in my past experience I had a missfire with the platinum bosch plugs when I had my 2000 celica GT-S which I changed out with some ngk plugs and the problem was solved. I've heard from my friend who is a service manager at toyota that bosch's are crap and that ngk or denso should only be used.

 

they won't benefit you at all. i had them on my previous ride (went from iridium's to bosch platinum 4+) and they didn't really do anything. wait until its time to change the plugs, then try them out

 

The stock plugs CANNOT be improved upon no matter who tells you whatever. Theywere the best available plug for that engine and that's why they were chosen to be put in the engine. Do youself a big favor and don't molest your perfectly good car!!!!

 

they are the best for the price for the stock form of the engine on the tune supplied by the manufacturer.

go tell the turbo guys not to change their plugs and see what happens LOL

 

I'm assuming we use a Denso IK20 equivelant. It's a great plug even for mild boost but when FI is thrown in, I'd go with IK22s. They have a colder heat range, and are gapped the same so no fuel efficiency is lost. For more power, they make IK24s but plan on losing some unneccessary amounts of fuel.

I think the stock plugs are great, and I feel that Iridiums are better than Platinums. Also, Bosch do stink. I can't remember how many fouled plugs or defective wires I had on my old 95 Eclipse (going way back...)

Denso is the best, NGK is great too. NGKs actually performed better but definately didn't last as long (leads to misfire and poor spark). Denso is the best compromise.

 

The iridiums are by far better than the platinums. And as Scott mentioned above is the reason they were chosen. Iridium has a very nice conductance characteristic, not the best of all metals, but very good. The best thing about them is that iridium is THE most corrosion resistant metal known to man currently, which is why the change interval for them is over 100,000 miles. While I agree that will serious mods and FI you may need to move to a colder plug, but stick with the iridium, it is pretty much the best thing going right now.

 

bosch platinum 4+ are great. had a 96 camry 4cyl with intake, exhaust, MSD ignition- used bosch platinum 4+ for 6 mos - felt improved throttle response AND increased in fuel economy by about 1/2-1mile per gallon. When iridium was the trend, i switched over to DENSO iridium.....cost me $$$... was a waste compared to bosch platinum 4+ because I lost power and fuel economy with the DENSO iridium in a 3 wk span. So, I switched back to bosch platinum 4+ and got my throttle response and fuel economy back. this is personal experience. Those bosch 4+ still performed after 50k miles....even with the MSD ignition shredding the crap out of it

 

You cant tell a 1 mpg increase in fuel economy. The mileage can vary up to 5 - 10 mpg depending on a ton of factors. If you averaged your mileage over a year with each you would statistically have an IDEA that it had improved maybe, but no way over a short span.

The iridiums will last nearly 3 times longer than platinums.

The performance I would have to see on a dyno over an average of runs, because, like the mileage it will be a tiny difference.

Finally, you cant compare with a 96 camry, because a lot has changed in the technology since then. And you were also running an aftermarket ignition module. This system was designed together, so the results will not necessarilly be the same. Not saying you had no improvement on the camry, but the small differences you mentioned are not well told without a long term analysis.

 

do you have personal experience with bosch platinum 4+ and DENSO iridium spark plugs with trials on the same car? I drove freeway about 75/day on that car and average out the mpg EVERYTIME I loaded up on gas. Based on standard conditions that I set and drove everyday during that test, I did notice the difference and the mileage drop with the denso iridium spark plug. I had 190k on that car before it was sold, so I know that car and its efficiency, and all the other brands of spark plugs that I tested along with that. DENSO iridium felt like the stock plugs in throttle response AND fuel economy.

As for the lasting 3 times longer, the bosch platinum 4+ will get you 100k miles with no problems. I did on mine even with the MSD ignition. Bosch platinums have 4 tips, so if one is slightly worn, spark will travel to another, so it will always find the least resistant pathway, giving the most spark. So, iridiums last 3x longer, meaning it'll last 300k miles? I think I'll still change my spark plugs about every 60-75k miles, regardless, due to structural integrity changes. So, I rather have the performance gain with periodic change of spark plugs during each stretched schedule tune-up, rather than having a longer lasting plug beyond the stretched schedule tune-ups.

Dynos and real life are sometimes different. A drag car may have 1-2 more horsepower on dyno, but not perform as well on the track, even with the same driver.
The MSD ignition was kept a constant with both spark plugs.

Sure, the technology has changed. Now, the tC has individual ignition modules, so the spark should be alot stronger and close to the MSD ignition. When they come out with iridium 4+, I'm on it. As for now, I'll use up my stock tC plugs until it's time to change. Like I said, I think the bosch 4+ are great based on my personal experience.

As for bosch platinum 4+ and tC application, I can't say because I have NO personal experience on this to talk about it.

 

^^^

I dont need experience with those particular plugs to tell you that you WILL not realistically see a 1mpg difference in mileage in that short of a span. To do that you are telling me your car got EXACTLY the same mileage every time you drove it (which will never happen), because if your numbers are off even 1 mpg from run to run you have completely lost your calculation. That comes down to simple sampling and math.

As far as durability, you just said above that you could say they would perform after 50k, now you say 100k.

I have had experience with Bosch in general, and they lasted LESS time than any standard plug I ran, which is why I switched back. Many of my fathers customers as well have switched back to Delco even after running Bosch. I personally have never gotten my moneys worth out of them.

I dont want to get into a ____ing contest, but I know enough about math and cars to know the gas mileage part is not a reliable calculation. I have driven mine to OK from MN approximately 6 times so far, taking the EXACT route each time on the 620 mile (one way) trip. I see the mileage average for that trip alone change by up to 5 mpg one way or the other. The same with my other cars. And you are telling me your car was so stable that it ran the exact same numbers all the time and you could see a 1mpg increase, which wont happen. you may have calculated it, but you could just as easily blame it on any of the other variables that effect economy. To calculate such things you need controls. Meaning NOTHING else can possibly change other than your variable, the plugs. This means fuel, outside temp, humidity, road conditions, tires and on and on have to be exactly the same, especially to quote such a small change. did they increase mileage? That is possible, and I am not saying it isnt. But the difference you calculated cannot be pinned on the plugs with all of the other variables in place.

But, arguing is not what I want to do here. I do respect your opinion and your experiences in the matter. We simply dont agree in this situation, and we are getting some good info posted as well. But a good debate is always fun

 

If the Bosch plugs could possibly yield a 1 mpg increase in MPG why in the world wouldn't Toyota put them in the car at the factory??????That would be just the ticket to raise CAFE up a bit and save tons of money. Maybe the Toyota engineers aren't quite as savvy as you.

 

cost. duh.

 

Denso iridiums are more expensive.... .I will be nice and leave the little kid "duh" off of my reply

 

Lets imagine that those silly plugs were twice as expensive as Denso Irridiums, yet yielded better MPG. Do you really think the Toyota engineers would pass on them for a dollar or so? Seems silly when you really think about it.......maybe you should really think about it before you post silliness.

 

Agreed!

True Japanese Denso Iridium plugs, you can't really do better.

Don't believe the hype of all these magic plugs getting you +4 HP or whatever.

 

i doubt at the quantity the toyota gets them at. i'd imagine getting plugs from an american company (bosch) as opposed to the japanese company (NGK/Denso) would be more expensive with taxes and such.

 

"In 1886, Robert Bosch founded what he called his “Workshop for Precision and Electrical Engineering” in Stuttgart, Germany.
" The higher CAFE rating would offset any price difference in the plugs no matter what. But yet they still don't use them.......

 

true.. didn't think about the CAFE benefits.... oh well


either way back to the original point. don't waste money on bosch platinum 4+ when you don't need them.