christiondavid

hello i have a question i have a 1971 super beetle with a 1991 13b turbo11 engine fully rebuilt ported and polished with a t70 tubocharger holley 750dp blow through carb, aeromotive a1000 fuel pump and aeromotive regulator anyhow my question is befor i fire her up what spark plugs would you guys recomend ?? i know they say to use a colder plug anyhow thanks.

RotaryRocket88

iTrader: (7)

Stock would be NGK 7s for leading plugs and 9s for trailing. You could run 9s all around for a little added protection.

asianguy02

iTrader: (4)

the NGK part number is 5255 at your local auto parts store, or anywhere else you may look for them.

canonize-ryda

Ngk also has sets on ebay for pretty cheap. they come with 2 leading plugs and 2 trailing plugs. good price compared to auto parts store. just have to wait a week for shipping.... they also have kits with 10.2mm wires if u dont have highoutput wires already..

Aaron Cake

iTrader: (1)

Hm, that will make a crazy amount of power for that car. If you intend to stay under 15 PSI, then 7s and 9s as suggested. If you are going to be running 15 PSI and above, then 9s all around.

I don't even know how you'll keep traction at 10 PSI, let alone 15+.

christiondavid

thanks guys, but rember that even thoe its a 1991 engine it is carbed now will that make a diffrence? or stick with the 7 and 9 or 9 all the way around? i will be running 12psi max, one more thing i do have a lm2 air fuel ratio meter what would be safe readings?

RotaryRocket88

iTrader: (7)

Carbed or EFI won't matter. If you're running high boost, you're likely also going to have some very high combustion temperatures. Running colder leading spark plugs will reduce the risk of preignition/detonation, since the plugs will disperse heat more readily. The downside is that there may be a negative affect on starting and cold idle.

Target AFRs will vary depending on boost level and throttle input, but generally speaking at WOT: around 12:1 at low boost, then progressing into the 11s or even 10s depending on what you have to cool the intake charge (intercooler, water/alcohol injection) and what the boost level is. Here's a thread with a large AFR table you can use to get an idea: https://www.rx7club.com/rtek-forum-168/new-target-afr-tables-890528/.

christiondavid

i just wanted to say thanks to all the replys, i wanted to stay on the safe side for now so i sent to get the ngk 9 all the way around, again thank you for your help.

christiondavid

i knew i would forget something where should my timeing be 10 even or 12 degree max? and how in the world could i put this thing on thoes timeing marks with a stock pully ? leading and trailing, ty