katz_2003

iTrader: (5)

I got an AI385 stroker all forged runnin 11.3:1 compression should be around 430-450 rwhp. Need help choosing a plug. I don't know if I should run a tr6 or a br7ef. And plug gap? Should I be around .036-.040? I had a tr55 @ .040 but its breaking up at high rpms now. I got 1k miles on the motor, could I have messed anything up running too hot of a plug?

RamAir95TA

iTrader: (2)

I have a similar setup as you and I'm running an NGK TR6 gapped at .035".

nitrous2fast

iTrader: (2)

stronger coil or a digital 6 might help with the spark breaking up at the higher rpms. The TR6 at .40 then go less if you need.

RamAir95TA

iTrader: (2)

An already missing/faulty ignition system won't be fixed by ADDING another component, not to mention the benefits of adding a piggyback ignition system on most N/A cars doesn't extend beyond being a conversation piece. And the stock coil is plenty strong for most cars, too.

Fact is, in competent hands the OEM ignition system is very good.

nitrous2fast

iTrader: (2)

Well he shouldn't have any problems on the TR55's either but he is... 11.3/1 only pushing what he is isn't creating enough pressure for the stock system to not fire the coil, BUT a coil going bad/weak would.

The piggyback does help with millage and def when using a colder plug. With the plug being recessed the multiple sparks help to make sure the mixture is burning. They also make sure the STOCK coil has enough energy to charge at high rpms.

speed_demon24

iTrader: (6)

I'm running autolite 104's. I had problems with tr-6's fouling on me a couple times so I just stick with the autolites.

RamAir95TA

iTrader: (2)

Spark plugs don't foul themselves.

speed_demon24

iTrader: (6)

No they don't, but I've had 2 occasions where TR6's fouled immediately then I replaced them with autolite 104's and have been running them since without any issues.

gregrob

iTrader: (8)

Lmao.

Wicked94Z

iTrader: (26)

i'm a dumb noobie, what's the difference between a tr6 and an autolite 104?

gregrob

iTrader: (8)

Big difference in heat range it would appear.

Both copper core projected tip

Penz

iTrader: (1)

I am running autolite 104s and I believe I set the gap at .35
Couple years ago my car started breaking up at high rpm (5500+) and it ended up being the Opti so maybe that is where you need to start troubleshooting.

big steve

And how old is the Opti? If you think it is the plugs gap a set at .020 and see if it gets better. To me it sounds like a optispark or a bad set of wires. Make sure a wire is not touching a header tube. It is so easy for one to touch and real hard to see.

katz_2003

iTrader: (5)

Thanks for all the replies guys. I put in a new set of TR6's and it cleaned the top end right up. I had #8 plug foul for some reason it was very fuely, but after the change pulls like a **** all the way up! I cant believe the job AI does with their head/cam set ups. I've raced a couple head cam ls1's and a couple forged lt1 355's with head cam and I just pull on em like nobodies buisness!

katz_2003

iTrader: (5)

The Opti is brand new GM unit so I was hoping that wasnt the issue and thankfully it wasnt. i need to get this thing Dyno Tuned now to see what kinda power she really has! At first I didnt have the TPS/throttle blades set at the right voltage ".067 volts" so I dont know if that kinda flooded it out or not but for now she's fixed

quik95lt1

iTrader: (7)

br7ef is wayyyy to cold for you........tr6 is ur ticket.........i ran br7ef's in my motor sucessfully last year at 13.9:1 CR..........7's will foul out in a 11.3:1 motor...........tr5's may even work for you that CR isn't too high

Wicked94Z

iTrader: (26)

still don't know why mike is tunning a tapered seat plug in a gasket seat head....

ThreeHonks

iTrader: (10)

I would actually go with a tr-55 and gap it down to about .040"

quik95lt1

iTrader: (7)

my heads are tapered seat

gregrob

iTrader: (8)

Mike I have to respectfully disagree on the BR7EF fouling out. We run them in several cars at stock compression and have never had that issue, provided the tune is on.