What plugs to buy?

Hi Group - I have the 1915cc motor in my Vintage Speedster. I decided to change some plugs, since they'd been in the car for a couple years. I took out the plugs, and found the Bosch WR8CC.
I went to Napa, and they said they have to order them, and they were a "hot" plug. What plugs do you run in your speedy for stop and go driving? Thanks

Mike my VS 1915 engine came with Bosch 7502 plugs and it ran great
getting 30 MPG on long trips.

Now I have a Type IV engine in the car and it uses Bosch WR8CC which is a "resistance" plug--whatever that means---the engine runs spectacular.

I think a resistor plug is an alternative to resistance plug wires.

They both prevent radio interference.

I don't think you would want to run both resistor plugs and resistance wires.

So, probably Mike would want to determine what kind of wires he has before selecting plugs.

BWAAHAHAHAH -- "radio interference"?? You must be joking. In a Speedster, radio interference is defined by the wind and the engine fan and also maybe your muffler system choice. Come on, get real, who listens to their radio w/ all that sweet mechanical symphony going on?

Ok, OK, I'm just funnin' The resistor in the plug supresses the RF emitted by the spark and makes the radio (especially AM, and who listens to that anymore??) not have an RPM dependent static. It will help the guy sitting next to you at the red light too, since our cars are plastic vs. metal, and so the body offers little to no RF shielding.

So if you DON'T run resistance wires and you DON'T run resistor plugs, then the guy sitting next to you at a stop light can't listen to Rush while you're within, oh.....say....200 yards.

Not necessarily a bad thing.......

try n.g.k. plugs they would be a b6hs they should woek great. bill

The WR8CC (new #7904) are 14mm x 3/4" -- you do not want to replace with 14 mm x 1/2" plugs. Conversely, if the threaded portion is only 1/2" then don't use 3/4" as they may hit tops of pistons plus threads will get carboned up and strip threads when they are removed. We all need to create a build sheet - worse thing you can do is order parts by engine year or the engine number --- as entire guts have probably changed over years of being rebuilt.

I too prefer NGK over "Botched" plugs (especially the platinum tipped ones).

Mike:

I, on the other hand, simply LOVE Bosch plugs in a VW, and would never even THINK of running those Japanese NGK "ricer-plugs" in my German heritage engine.

Having said that, why would you even think that something other than the W8CC plugs that came out of your car would work better than what the engine builder (or previous owner, even...) put in there??

I am running W8AP BOSCH Platinum plugs in my engine and I love 'em. That comes from many, many years of running Platinum-tipped plugs in very high performance snowmobile applications and loving them there, too (wouldn't run anything else).

You don't have platinum plugs in your engine, but the "8" designation indicates that you have a slightly higher heat range plug. Not necessarily a bad thing in aircooled applications and will avoid mis-fires at higher RPM's. That's pretty cool,too.

So.....Why are you replacing your plugs after only two years? Has the engine done more than 12,000 miles in two years?? Put the same plug type back in there and you're good to go for another 12,000 miles, unless you use W8AP's and then you can go for 100,000 miles between spark plug changes. I'm still running the same set of Bosch, W8AP plugs I built my engine with in 1997 and, with only 16,000 miles on them they're just getting "broken in".

Gordon
The Speedstah guy from Beaufort

Be aware that when you compare Bosch and NGK plugs higher numbers are hotter in one and colder in the other.

Gordon, you killed me with the "Rush" comment!

I guess I am guilty then. Non-resistor plugs and wires, and distributorless, killer spark! And what's a radio?

NGK DP8EA9, as spec'ed by Jake.

I tried the Bosch WR8AC+ but found (much to my surprise) that my particular VS 1915 preferred the NGK.