Copper or Iridium TR6's w/ 125 wet shot?

[hotmustang331]

I dont know if this helps you Jive, but Tim told me to gap mine @ .035. He tunes ALOT of cars, so im sure he knows what gap works on S/C cars.

But I have to go with randy on the fact that with MOST plugs, dont go lower than teh .040s. If you close them too much your car will run like crap while N/A.

The reason for gap depends on compression ratio and cylinder pressure. S/C motors run a tighter gap to prevent spark blowout with the higher cylinder pressures. same thing for high compression motors....like said the NGKs come pre gapped and are designed for the gap that they set them at, but that specific plug isnt JUST for N20 cars...its designed to be used in high cylinder pressure enviroments. So it will probably be sacrificing milage, and some power while N/A. I would go about .038-.040 . Remember spark blowout shuldnt hurt your motor, but you will know when you have it. I doubt a 125 shot will blow out a .040 gap. But thats JMO.

 

[BooWFO]

Randy - My response was due to the fact that coming from a hotrodding background it was normal to play with the plug gaps to find what works best we used the old rule of opening or closing a gap by up to .008 to acheive our best perfromance. However whenever I voice that on forums someone has to chime in that I have no idea what I am talking about. I also checked my tr6's when I got them and all of the ones I've installed in my buddies cars with feeler guages and they have spec'd at .035 in my car I have got the best performance at .040 which is within the old rule I was taught about opening plugs up. Plus it's a nice easy to remember #. Once again this is for a combination daily driven car that sees some nitrous action.

OK lots of nitrous action.

 

[LaserRed01GT]

Thanks again for all the input. The one thing I have learned, and I agree with BooWFO, is that the only way to find out which gap TRULY works best is to go through trial and error.

I have them in at .033 right now and it seems to pull pretty hard N/A. I will try closer to .040 this weekend and see how it runs N/A and on the bottle. Because, this is my DD right now, and it is important that it run good N/A as well.

Bottle is sitting in the freezer over at Automotive Engineering right now.

 

[LaserRed01GT]

BTW, what's the general consensus as to how much power at the crank the bottom end is good for?

 

[hotmustang331]

420RWHP. Crank should be around 475 hp.

 

[LaserRed01GT]

420RWHP. Crank should be around 475 hp.

Thanks, that's about what I'm hearing. I think I may ditch the N20 and do a nice heads/cam N/A setup. It's just nice to have the power available "full time" you know.

What can I expect to the wheel on a fully ported head and decent cam N/A with my setup? My version of "streetable" is a little more extreme than most.

I hear lots of people taking advantage of using the SVT foucus fuel pumps when the fuel system requires it. How much HP at the crank is the stock Mustang 4.6 fuel pump and the SVT Focus good for?

 

[BooWFO]

420RWHP. Crank should be around 475 hp.

maybe maybe not

I know I'm not the only 2v guy that has busted the 430rwhp mark on spray.