NGK spark plug heat range question

Reply Subscribe

Thread Tools

05-12-2008 | 11:47 PM

#11

DMOORE

Registered

Joined: Jul 2007

Posts: 988

Likes: 2

From: San Diego

Quote:

Originally Posted by blue thunder

Interesting. I was running r43xls last yr NA. Per Laz's method it looks like 2 turns of color on those plugs, so a tad cool. This yr I am running 4lb boost so I wanted to go 2 sizes cooler than the 43s to 41s. Those I could not find, so I went to the NGK site and crossed it to an NGK plug. I found the equivilant plug to be a BPR5EA - L - 11 per their site. It seems that 8s would be too cool, but I don't know. Take it for what it is worth LS!.

Man, a #5 seems REALLY hot for a blower motor. Sure the cross reference is correct?

Darrell.

05-13-2008 | 04:00 PM

#12

blue thunder

Registered

Joined: Nov 2001

Posts: 3,393

Likes: 6

From: IBX

Quote:

Originally Posted by DMOORE

Man, a #5 seems REALLY hot for a blower motor. Sure the cross reference is correct?

Darrell.

No, I am not sure. So I called NGK. They said you can't trust the distributor cross ref sites. Holy Shiet! They recommended 7s or 8s. I ordered race series 9s to replace these 5s. Thanks for the heads up before I started breaking stuff DMoore!

05-13-2008 | 06:40 PM

#13

DMOORE

Registered

Joined: Jul 2007

Posts: 988

Likes: 2

From: San Diego

Quote:

Originally Posted by blue thunder

No problem at all. I was just looking at that #5 and thinking, I've never ran a plug that hot in any aplication before.

Darrell.

05-15-2008 | 08:53 AM

#14

ls1nova

Thread Starter

Registered

Joined: Jul 2004

Posts: 388

Likes: 1

From: Cecil County, Maryland

Quote:

Originally Posted by axapowell

Frank,

I have basically the same motors with a similar set-up and I have tried both the "9's" and "8's". I have found the 8's run cleaner and the read is good.

Dave

Thanks for the info Dave! How much total timing are you running in your motors?

Frank

05-15-2008 | 08:56 AM

#15

ls1nova

Thread Starter

Registered

Joined: Jul 2004

Posts: 388

Likes: 1

From: Cecil County, Maryland

Thanks for all the input guys. I talked with the ngk tech line and they suggested I start off with a 6 and go from there. I actually ended up getting 7's to start with, but I have a feeling I may end up with 8s in there.

Frank

05-15-2008 | 08:59 AM

#16

axapowell

Where To

Joined: Nov 2001

Posts: 2,517

Likes: 4

From: Alexandria Bay, NY 1000 Islands

I am running a Crane HI-6M and set initial at 16* the box puts in an additional 20 (all in) at 2500 rpms for a total of 36*.

That was on the advice of Bob Teague. Never a problem after 125 hours of running!

PM me your number if you want to talk!

Dave

__________________
Air, Sea, and Land...Exploring the planet in 3-D!

05-15-2008 | 01:08 PM

#17

Wobble

SORE MEMBER

Joined: Apr 2004

Posts: 6,984

Likes: 2

From: 29°50'49.74"N 95° 5'17.55"W.......TEXAS

Quote:

Originally Posted by ls1nova

I have been running 7's for years per the NGK tech recommendation. NA motor iron heads and 9.3-1 compression.

Tried 8's and found them a little more prone to foul, though they would always clear out when I made it out of the first no-wake