vibrantvivid

i just had my 2002 protege 5 dynod today and was suprised. first off i did not have a basline run in stock form. the base line run i had today was with my injen cai and a babatech axle back exaust system. the very first run i threw down 102.2 hp and 114.5 max torque. second run no mods or changes i put down 102.0 hp and 114.2 max torque. third run i let the engine cool off for about 15 minutes and put down 102.1hp and 114.5 max hp. the final run i switched out the sparg plugs with some denso iridiums and put down 103.8 hp and 116.0 max torque. the stock plugs looked like **** and had some serious carbon build up on them for only have 3700 miles on the car. i was pleasntally suprised with the plugs 1.6 hp gain and 1.5 torque gain for $60 aint that bad also i noticed that the power is much smoother with these plugs.

anyone that has had their car dynoed can you please tell me what your hp band looks like from idle until about 2750 rpms. mine is very jagged. is there any way to correct this so it is smoother and more efficient?

ZackyFarms16

sweet, what kinda plugs exactly? like manufacturer or whatever and stuff. thanks.

vibrantvivid

the company is called denso and the plugs are iridium power.

ZoomZoomH

you said your old plugs had a lot of carbon buildups. Just out of curiosity, what octane gasoline have you been feeding your Protege5?...... Not accusing anything, just seems weird that there would be significant carbon buildup at only 3700 miles...

ProtegeES

what model number? I want to get some!

HLJjr

I'm very interested to hear what fuel you run as well. With all the previous discussions regarding premium fuel and the potential for carbon build-up, I'm dying to know. I've stuck with regular and have had no dreaded knocking/pinging even driving on the surface of the sun (the Sacramento area, actually, but it's damn near as hot).

zeriak

Check out this site. It's from NGK's web page. NGK sells irridium plugs as well, but this tech tips section tells you why racing cars have to use racing plugs and what not. Lots of good info here. I was thinking of getting irridium spark plugs as well, but after reading this, I'll just go with regular NGK's.

http://www.ngksparkplugs.com/techinf...s/techtips.asp

Here's a couple excerpts. I recommend reading the whole bit though.

With modified engines (those engines that have increased their compression) more heat is a by-product of the added power that normally comes with increased compression. In short, select one heat range colder for every 75-100 hp you add, or when you significantly raise compression. Also remember to retard the timing a little and to increase fuel enrichment and octane. These tips are critical when adding forced induction (turbos, superchargers or nitrous kits), and failure to address ALL of these areas will virtually guarantee engine damage.

Hehe this is a good one for 'Ricers':

However, installing the same spark plugs Kenny Bernstein uses in his 300+ mph Top Fuel car (running Nitromethane at a 2:1 air/fuel ratio and over 20:1 dynamic compression) in your basically stock Honda Civic (running 15:1 a/f ratios with roughly 9.5:1 compression) will do nothing for you! In fact, since Kenny's plugs are fully 4 heat ranges colder, they'd foul out in your Honda in just a few minutes.

vibrantvivid

ive been using 92 octane from texaco. the weather here has been warm around 90-95'f. i believe the part number on the box is 5303#4 there is another number on the box that is ik16#4.

ZoomZoomH

NOW will you consider using the CORRECT octane grade (87) for you P5????

congrats on being the first person to be brave enough to show concrete evidence that running higher octane gasoline than recommended will actually DECREASE your car's performance....

vibrantvivid

i never saind that about the octane fuel i was putting into my car lost me some power.

ZoomZoomH

well, then how do you explain the heavy carbon buildup on your original spark plugs, on an engine that's only been through 3700 miles?

As been discussed thoroughly in the past on this forum. running gasoline too high of an octane rating on our engine would result in incomplete burning of the fuel, which in turn creates carbon buildups on the spark plug, which, as shown in your dyno results, decreased your power output by 1.6hp.

conclusion? premium fuel on STOCK protege engine = waste of money AND decreased performance

Patio

why thats ODD, i run 92 octane all the time, hmmmmm? Should i use 87, Mr. Genius?

ZoomZoomH

why, you should!

EDIT: waiiiit a minute, just checked your sig, you have nitrous hooked up. I was referring to STOCK engine setup. You can fill with whatever you feel like Patio!

Sil_Pro5

huh? can you re-type what you said? not trying to be a jerk, i just cant understand what you said. and if youre saying what i think youre sayin then, yes, im not surprised that you did lose hp.

the ONLY benefit from running premium fuel (if one can call it that) is that, the sulfer in the gas will be lower than in the say 87. the higher the sulfer in the fuel the higher the TBM of your motor oil has or should be. but thats for a whole other discussion......

David

ditto
there is NO gain from using the higher octane. if te car says that it should be on 87 then it will run the best on 87.