design of plug i would believe straight up, heron chambers are massively different from a flattop wedge. 3k plugs in a 5k is more like, using the wrong plug, than different brands of plugs making a difference :)

 

i'd be interested to get my hands on a "money back guarantee" set of hundred dollar plugs and back-to-back dyno test them with 4 dollar plugs. i'll bet there's f@$k all difference

supercamry had denso plugs too. it went heaps better with the densos than it did with no pluga at all. still can't work out why though...

i have issues with bosch anything, down with bosch

Dam right, anything bosch is shit, relays, plugs, leads, electronics you name it.

...fuel pump for your bmw, bosch motorsport high pressure (yes it was stock), second hand $500...

i was supplied bosch glowplugs in my diesel when i got it rebuilt, and after 10k one stopped working and when i pulled it out the tip of the plug had nearly fallen off, ifit had of fallen off my $6000 rebuildwould have been for nuffink and my piston would have smashed thebroken plugin to the head leaving me with a new head to buy and a new piston at least and since i had it unsleeved myblock could have been stuffed in short

 

I WILL NEVER GET BOSCH ANYTHING AGAIN....

welcome to the official rollaclub anti-bosch thread :jamie:

so its.

 

Bosch = NO f@$kING WAY

 

NGK = Good no conplaints

 

Denso = Also Good.

 

hmmm.....i'd be interested on which plugs are the long nosed ones?

they're in the catalog as an AU falcon plug, easy to find

but they only sell them in sets of six!

 

from memory, there's also a long reach corolla plug (like for 4A-FC AE92 or some shit) but it's got the smaller size fastening nut on it

often also, ignition based things usually won't improve power if the existing system is working ok, but will improve the overall smoothness and burn quality of the engine

 

like when we went from crappy old 5mm leads, to custom 8mm leads on fook's 4age. instantly the car just idled so smoothly and built revs quicker and steadier, and it sounded alot less rough running. perhaps you could have measured the combustion quality with a gas analyser in that case?

doug has gas analyser :jamie: if rollaclub ends up with a spare hundred bucks one day, the site could sponsor a spark plug comparison tech article?

a friend of mine tested different spark plugs on his volvo 240, b23 2399ccm rally car on dyno

there was something like:

cheap spark plugs 270 something rwhp

ngk spark plugs about 4hp more than the cheap ones

some kind of motorsport expensive plugs 7hp more than the cheap ones

but the expensive plugs did cost 4 times the price of ngk plugs

I don't remember the name, but I will ask him

 

he actually have to change plugs when the engine is warm to get more hp out of it..

 

I'm using bosch plugs with 4 things instead of one in my 4age, the plugs are a bit old so I guess I should buy some new someday

Edited July 21, 200521 yr by David

did they go back and test the crap plugs again afterwards? 7hp variance out of a 270hp car is like 2.5%, that could be a bit of breeze in the dyno room introducing cold air, or just plain old mechanical inconsistency. but if it's a good solid repeatable result, that's very interesting. i'm keen to hear more :jamie:

I'm not sure about that, but I will ask him when he gets back from his vacation..

 

but I guess you would not see soo much difference in a 4k or 4age, because that engine was highly modifyed

that engine would cost him about 15k USD if he didn't get sponsored, so he only had to pay half the price.. and therefor the cost of spark plugs doesn't really mather much, since he buy new spark plugs for every race he drives.. ohh you should have heard the sound of that engine.. very angry;)

can't even compare it to my 4age which also sounds a bit angry with my current exhaust setup

Edited July 21, 200521 yr by David

the cost of spark plugs doesn't really mather much, since he buy new spark plugs for every race he drives

grab the old ones :jamie:

is it time to change plugs when they look like these?

:jamie:

they was in my spare 2T engine I have in my garage