Sof86

Recently was checking my plugs and found that I have NGK TR7's (shop installed them). Is there any reason to run these in a N/A build? Car is tuned for 91 octane.

StealthFormula

iTrader: (35)

That's strange, definitely a mismatched plug for an 11:1 N/A setup. They must be two steps colder than stock plugs, ditch those for something else. My compression is similar to yours and I've personally had good luck running Autolite 104's which are a half step colder than stock.

BTW are they fouled?

HCI2000SS

iTrader: (2)

A TR6 would be a better choice. At your power level there is no need to go with that plug

Sof86

I actually haven't taken them out but they very well could be, the car hasn't been running right lately. I noticed it when I was pulling and resetting the plug wire on the plugs, from a certain angle I can just barely see the number "7" on the plug and these are NGK brand.

I'm not sure if I can find or buy Autolite's in Canada. I was thinking of going with the TR6, called my local Napa store and they have plenty in stock.

Sof86

Yeah was thinking of going with those instead. Seems like the TR7's are more for turbo, sc or n2o cars after doing a bit of research.

LivernoisMotorsports

iTrader: (1)

The TR6 is the winner the 7 is a little too cold for n/a on 91 octane.
we have plugs and wires in stock at all times.

HCI2000SS

iTrader: (2)

Just for reference I run BR7's only because I have nitrous. I used to run TR6's before the nitrous though and running n/a I can't tell one bit of a difference. But I'd still choose the TR6 for a n/a only application

flyinZ

iTrader: (15)

Dang, I thought the TR5 plug, was a good choice for an N/A setup...I was wrong.

97pontta

iTrader: (10)

My setup is 11.3:1 as well and I started off with NGK TR-6 plugs and I felt they were a little too cold for my engine after running them for a while and reading the plug and they seemed to be fouled. I switched to NGK TR-5 plugs and they read better and that's what I've been running the the past 2 years. At 11.3:1 your only about a point higher than the stock 10.4-10.5:1 so going to a colder plug may not be necessary for everyone, some guys can get away with the TR-5 and some need a colder plug.

StealthFormula

iTrader: (35)

Same here. I don't know why everyone recommends the TR6's for NA LT1 setups in the 11:1 range. I ran them once and kept my eye on them and sure enough they fouled. Stock bottom end 11.3:1 compression.

Shownomercy

iTrader: (1)

I run TR6s 9.5 SCR

Chopstix

iTrader: (1)

I assume everyone missed the fact he doesn't have LT1 heads...IIRC the canfields are similar to the old AFR castings and will run a colder plug

NewOrleansLT1

AFR recommend different plugs from stock.. But I run rapid fire AC Delco's with my AFRs and they're fine.. I'm about 10.8cr

97pontta

iTrader: (10)

I didn't notice they were Canfield heads, but even with different heads there is no way of saying run plug XXX with a cretin setup. Best thing to do is read the plugs that are in the engine and make the decision according to how they look.

kinglt-1

iTrader: (26)

TR5 is good for stock bolt-on setups. TR-55 is perfect for most NA setups with compression up to 11.5:1. TR6 for max effort NA or boost. Non projected tip BR7 for nitrous up to 200hp.