hypersurf1

I got my car on the dyno today with the Paxton 2200 HO. First pull was 420HP but she was missing a cylinder over 4000 RPM. A/F ratio was good at 11.5 and not higher under load. These are stock spark plugs and we think its spark plug blow out from the pressure. Looking for a confirmation or other ideas. We did put in the dual fuel pump setup and the A/F is good. According from what ive read we should hit 470HP on all 8 cylinders. Thanks.

hammeron

if you're running 8-10 psi, you may
want to gap your plugs to .032

you may also want to consider going to the
HT0 plugs

ratnacage

+1, Missing under boost is nearly always a spark issue. You'll need a special tool to gap these plugs.

hypersurf1

Thanks guys. I will pull the plugs and gapthem and dyno again. They only have 3,000 miles on then so i dont know if im gonna replace them. I will do .32 as that sounds like a good point to start.

cfr865

My Paxton 220 was installed by Brenspeed last March, they put in the HT0 plugs but left gap alone. The car has one fine since, I have put approx. 4,000 miles on it,and ran a 11.9 117 at the track with an a/t. I haveseen that some have re-gapped there plugs but Brent said it's not necessary, apparently it's not or wouldn't have run an 11.9.

moosestang

It shouldn't be necessary till 10psi or more. I believe the whipple 3.375 inch pulley actually makes 10.5psi. Anyway I would definately get colder plugs if you are running 10psi. If you had spark blow out at high rpms i'm sure you'd know it.

hypersurf1

At 6200 rpm i was at 12psi of boost with 420rwhp and alot of miss. 500rwhp is my goal so I will work on it. I am on the stock plugs and gap so i will be bringing the gap tighter.

killbee

I would get the colder plugs for sure ecspecially if you run over 10psi. I would also get a set of MSD COPs to keep them lit. I saw a turbo GT on a dyno blowing the spark out at 11psi with the stock COPs.Its better to be safe than sorry, 1 misfire under boost can load a cylinder and cause you to push a rod out the block.

p.r gt

i have the same problem and i have the ho plugs my kit is from brenspeed

06Saleen3V

At 12psi with your setup, you should be seeing between 460-500rwhp. So, once you get your problems fixed, you should be near your goal if not at it