After a frustrating year-end in August 2011, when I blew up my FAST 92mm intake from melting the sparkplug strap on #7, I'm commiting to reading plugs this year! I have to admit this incident was completely my bad and nothing to do with the safety of N2O or the sponsor's equipment. I was racing and running a 88 N2O and 44 Fuel jet and NANO (55 psi in dedicated) total of 14 degrees timing and #9 plugs. A/F Gauge was not working due to faulty sensor. 1st run ran a 10.53 at 129.7 mph and lousy 1.642 60 ft. This seemed slow so I leaned it out by lowering fuel pressure in dedicated to 50 psi and ran a number of runs in the 10.4s at 131ish still slipping off the line with high 1.6s 60 ft. This is when I had a brain cramp, and despite the fact I was already spining off the line and had not read the plugs or had an A/F reading I decided to add a degree of timing. Half way down the track there was a huge back-fire when the spark plug strap on #7 melted and fired on the intake stroke! I know, I know...I had no A/F reading to go by and was not reading the plugs - just got impatient and caught up in the racing -STUPID!

I have since completed the cooling line mod to help #7 cylinder and upgraded to a 102MM FAST intake and throttlebody along with a new 102mm N2O Nitrous Outlet Plate and 100mm MAF. Obviously I want to avoid a repeat of this situation this year so really plan to be disciplined with reading plugs. This is where I would appreciate some help. From what I have picked up from the site my current understanding is I want the timing mark at or slightly past the bend towards the end of the strap. To close to the base - too hot, too close the the end of the strap - too cold. Fuel ring should show very slightly tan at the base of the plug. Assuming that is correct I need to know the procedure to tune towards this optimum state. For example, if the timing mark looks good but the fuel seems rich would you just take 2 pounds out of the dedicated or would you also need to remove timing. This is where I get confused. If you remove fuel and run leaner (hotter) would it not require less timing to compensate for the increased heat? Alternatively, if you read the plug and the fuel seems lean and the timing mark is OK would you need to add timing if you add fuel (run colder). I'm really looking for a methodical process that I can follow based on what my base reading of the plugs tell me.

I know this is really wordy but I'm hoping to save someone else from having my experience from last year. Appreciate comments from experienced N2O guys! Thanks.

 

My opionion would be to take things one at a time, and maybe not so much. Instead of taking 2 lbs of fuel out go in smaller increments, like a half or even a lb. And watch your MPH once you get the timing in the bend or so. Too much of one and not enough is never a good thing as you know, just take your time and it should all work together.

 

Give me a call and Ill give you one on one teaching.. Dave

 

take daves advice he is very good.

 

Closer to the base of the plug = to much timing.
You want the timing mark just on the tip of the electrode.
Get that there and a clean plug then you can play with 1/2* here and there and slightly more or less fuel to find out what your combo really likes.

Call Dave !

 

So tell me more on this #7 cylinder cooling line mod

 

i would like to know too.

 

As far as the cooling mod it consists of a redesigned rear vent tube that has a tee that connects to a rubber hose flowing back to the cooling system. It ensures no air gets trapped in the head causing hot spots in cylinders, especially #7.

 

would you happen to have a pic of this?

 

here is a great thread for you
http://www.yellowbullet.com/forum/sh...hlight=coolant

we need to do it to ours soon

 

Thanks! Do you think its worth doing?

 

Most definitely, only plus sides to it

 

I just installed the Kurt Urban kit. Nice and simple. Maybe expensive but so is everything else on my car so what the hell.

 

my heads are comming off in about a month so i will most likely do it then. will it work if you use the same exact cross over tube that is on the front of the engine?

 

This is one reason I just sold my fast 90/92 setup. Thats alot of money down the drain if you get an intake backfire

 

Interesting read! I'll have to look into this!

 

All of you guys who have not done it yet.

Do it !!

 

will do! will that Kurt Urban kit fit under a fast intake?

 

Nope sits on top of it. Installed my fittings in the head and installed the rear lines, then installed the intake.

 

thats what i thought, ill have to run the lines on top.