Rah Rah

This is the setup on my 92 Integra LS:
1. Nitrous Works adjustable (25-50-75-100) wet kit
2. internally stock
3. intake and exhaust are the only bolt ons
4. stock timing
5. 137,000 miles on the odometer
6. compression in each cylinder 150 across the board before the blow up
7. running a 75 shot
8. fuel pressure at idle (vaccum hose disconnected) 46 psi (within Helms spec).

In the middle of a run at the track my car lost power. I immediately backed off the gas and coasted to the finish line. I pulled into the pits and my car was smoking badly, engine was misfiring like crazy. I pulled out the plugs and saw that the spark plugs in cylinder 1 and 3 were completely melted. Plugs 2 and 4 were perfect (BTW, I use NGK BKR7E's). The next day I ran a compression check and discovered that piston 3 had no compression whatsoever. This is probably like the 5th bottle I've gone through and never had any problems. I know some have told me to retard the timing, however nitrous works and nitrous express both say that it is not required. Obviously 5 bottles is a testament to that. Would it be a good guess that the lean condition in the fried cylinders was due to faulty or clogged injectors? I need help guys.

b18bturbo

i am pretty sure you detonated due to lean condition and too high cylinder temps therefore probably melted a piston.

DSF

To add to what Viren said, 150 seems to be on the very low end of an acceptable compression reading. Chances are your combustion was being contaminated from blow-by, adding more chance for detonation.

b18bturbo

another thing ifyou build it up again retard timing based on your shot. it will help you out big time.

Rah Rah

I'm feeling like crap to say the least because I won't have the car back for a while. I'm alos retiring the nitrous until I get a spare car and look into rebuilding the engine. I figured that 150 sounded pretty low. I've been trying to search through my Helms to find a chart or figure that would be acceptable psi for a B18A. Should it be more in the 180's? Also, I'm still trying to understand why it leaned out in only one cylinder.

DSF

I'm assuming this is a single fogger kit, with fuel and nitrous being injected prior to the thottle body? If so, there's your answer. OEM intake manifolds were never designed to evenly distribute liquids (fuel). Cylinder 3 typically runs hot to begin with (I've heard this though hearsay, not experience), so combine that with poorly distributed fuel and you're lower compression readings and well, you know the rest. And yeah, for a B18A I would guess 180's. It should say in the front of your Helm's, in "Design Specifications" or there abouts.

Rah Rah

Yes, I have the the nozzle that injects fuel/nitrous before the throttle body. It's the EFI "Power Wing" Nozzle Kit.


[Modified by sando112, 1:43 PM 7/24/2002]

PM-Performance

dsf is right on the money. single fogger kits are a apin to get the fuel to go evenly, fuel doesnt like to take the bends of the im to get into the head. so more than likely you just didint get fuel to those cyl and pop. . once wouldnt have done it prob. . . more than likely its from proliong use like that , along with timing , and the compression . . it just made it go quicker. i took out my single fogger kit for that reason and went direct port. its a great kit( single fogger) . but gotta keep an eye on everything to make sure getting dist evenly.

Rah Rah

itr206 what kit do you have?

PM-Performance

i got 2 kits actually.
actually 3
i got the single fogger wet kit , that was converted from dry . . so i still have all the dry stuff ,
and i have a direct port kit.

Rah Rah

Is it the NOS brand direct port?

b18bturbo

direct port only way to go but you cant really run small shot on them

Rah Rah

Well, all i know is that I'm retiring the kit

PM-Performance

everything i got from start to finish is NOS brand.