i read this in the other thread,..that is great stuff too. this topic turned into a very informative thread,..that should help everyone alot.

lots of GREAT info

heres a brain teaser for you guys... good ole LG3... (vin 3) ...with intake, modified rear manifold and full exhaust, DIS4, msd coils, type2 ign, JET stage 2 chip, 180 stat, removed EGR, and removed coolant lines into TB, beldin 7mm wires(or MSD DIY 6cyl kit if I can't find em the Beldins)

and 60hp nitrous shot (with use of Jacobs nitrous mastermind)

1 range cooler? 2? ... lil sticker under hood says gap should be .045 stock

any suggestions on the heat range and gap?

and I know everyone will say use the highest I can find... but which octane should I stay with?... I can get up to 94 oct here at the pump (I know atleast 91 oct as Jet says for their Chip)

other then that.. I'll post elsewhere about other thoughts I am having about engine mods to try and keep the tread remotely on topic

The MSD DIS4 ignition isn't going to be a power-adder. The fastest 3800'* in the country are running stock ignition. Just upgrade to a type2 delco system.

Switch to the Type2 system, and run NGK TR55 plugs gapped at .055". One heatrange colder. If you foul, go to the TR6. But you won't be running nitrous all day long, so one heatrange is probably fine.

With N20 you want to run 2 ranges colder. Allmachtige did.

Doesn't the DIS-4 allow changing ignition settings, like timing advance, rev limits etc?

So do you guys think I should get some Tr55'* in? I bought some TR55'* but turns out the guy at the counter (owns a modded L67 Regal) gave me TR6'* and I didn't realize until I was 40 miles away and had half of them installed. So I closed the gap a little (down to .058"). Seems to run ok, and my MPGs are up from 25MPG to 28 MPG.
BTW, the old TR55'* which I removed were extremely RED on the front bank, and only the #2 cylinder had a plug that was acceptable. I checked the gapping on the old plugs and they ranged from .058" up to .062" so not TOO far off.
Cylinders 4 and 6 had plugs that were slightly red, but mostly brown.

thanks for the info... is the type 2 that fits on the LG3-3 as nice as the type 2 that fits on the 3800'*? and I know the DIS4 won't give me any power gains... but it will allow me to be more consistant when I go bracket racing (2 step rev limiter) ...and the lower rpm multi spark should help me out in daily driving around town and on highway cruises in the mileage area... it may not mind you... but it should....it'* going to be one of the last mods possibly going on the engine

while we're on the subject of ignition upgrades momentarily ... will the L67 coils work/mount up to the old Type2 ign mod? seeing as everyone says there as good as the MSD'* and seem to last longer

I noticed a difference with the dis-4 for sure. I can't believe these heavy modded cars are not using one. Lowend TQ was much more noticable. I installed a DIS4 system in a stock GTP and he could not believe the difference. On my car the heads up jumps numbers by 2 or 3 depending on how fast i accelerate, so call it my poor mans g-tech. But after the dis I was jumping by 2 numbers all the way to 85. instead of only to 65 before that. The increase in MPG is very noticable. I don't understand why this mod gets a bad rap. My only regret is that i did not buy the High Output DIS. I counld not find it used like my dis 4 box I picked up for $250. I'm going to get new plug soon and with the DIS box and MSD coils and 200 amp alt I'm not sure how big of a gap I need or what heat range. Any advice?

Wow! Foghorn, and I thought I knew what spark plugs were all about! This is some good info you presented here. Thanks. Now I understand how serious my mods have to be if I'm running not only a SC but I also live where the outside temp is pretty much steady over 100F. Thanks again. I learned a lot

I just picked up a set of Autolite 605'* to replace the double platinum AC Delco plugs that are currently installed. I understand the heatrange of the plugs being signified by the last number (I believe that 6=stock, 5=1 step colder,4=2...), but why after the 605'* do the plug P/N'* drop to 104 instead of 604?