|
|
|
|
| Author |
|
|
Registered
Join Date: Feb 2007
Posts: 7
|
spark plug for 2.2L S
Hello:
I have a '68L. The matching-numbers engine was upgraded to 2.2 911S spec including 84mm Mahle pistons with 9.8:1 compression in Nikasil cylinders, 911 S camshafts, heads ported to 2.2 S specifications. I have added MSD CDI ignition with flamethrower coil. I have been running NGK BP7ES (part 1034) plugs and still get some fouling on a couple of cylinders after a few hundred miles. Mostly city driving, trying to keep it over 3000 rpm. Those particular NGKs are now discontinued. Looking for recommendations of a comparable or even slightly hotter plug that will resist fouling. Also, i would like to hear recommended gap with the CDI - .040? Thanks a bunch. Jim |
||
04-10-2023, 05:31 PM
|
|
|
Registered
Join Date: Feb 2007
Posts: 7
|
nothing?
|
||
|
04-12-2023, 04:40 PM
|
|
|
Registered
Join Date: Oct 2006
Posts: 315
|
I have a rich running 73S with mfi. Ive been using NGK BPR7es with MSD and gapping to .040 I
still foul. I just ordered Denso IW16 which is 2 heat ranges hotter than NGK 7s. This may be too hot for high rpm driving but if this does not clear up the fouling I'll send my pump out. Denso are fine wire and pre gapped to .040 Look into forum for rich running MFI see John Walker's contribution. |
||
|
04-13-2023, 12:57 AM
|
|
|
Registered
Join Date: Oct 2006
Posts: 315
|
I have a rich running 73S with mfi. Ive been using NGK BPR7es with MSD and gapping to .040 I
still foul. I just ordered Denso IW16 which is 2 heat ranges hotter than NGK 7s. This may be too hot for high rpm driving but if this does not clear up the fouling I'll send my pump out. Denso are fine wire and pre gapped to .040 Look into forum for rich running MFI see John Walker's contribution. |
||
|
04-13-2023, 12:58 AM
|
|
|
Registered
Join Date: Mar 2004
Location: Higgs Field
Posts: 22,582
|
Just put an "R" in there (for "resistor") - BPR7ES - and it's the same plug in a resistor version.
My son and I both run BPR6ES, one heat range hotter, in our MFI inducted (and rich running) motors. His is a 2.4 T motor in a '68 912, mine a twin plugged, high compression 3.0 in my '72. Plugs still run a bit on the darker side, but none ever foul and quit working, and they last a good long time.
__________________
Jeff '72 911T 3.0 MFI '93 Ducati 900 Super Sport "God invented whiskey so the Irish wouldn't rule the world" |
||
|
04-13-2023, 07:06 AM
|
|
|
Registered
Join Date: Feb 2007
Posts: 7
|
Thanks, guys. Both responding are running MFI, i have triple throat Webers. Any reason to think plug choice would be different for carbureted?
Also, I see the BPRE6S and 7S plugs are readily available (unlike the no resistor version). Any reason to think using the resistor version will be different or should that have no effect? Thanks, |
||
|
04-13-2023, 10:41 AM
|
|
|
|
Registered
Join Date: Oct 2006
Posts: 315
|
Allot of guys with thirsty carbs are using NGK BPR5es. Like Jeff said the “ R “ signifies resistor and I think that’s all that’s available now.
I would go with the 5s while turning then try 6s and see how it goes. |
||
|
04-13-2023, 10:53 AM
|
|
|
PCA Member since 1988
|
At first, stick to what MSD recommends. The spark plug gap specification depends on the energy the ignition system can deliver. If you want to experiment, of course you can, but do it a little at a time, testing at all load and RPM ranges. If you don't have any misfires or hesitation, open it a little more.
__________________
1973.5 911T with RoW 1980 SC CIS stroked to 3.2, 10:1 Mahle Sport p/c's, TBC exhaust ports, M1 cams, SSI's. RSR bushings & adj spring plates, Koni Sports, 21/26mm T-bars, stock swaybars, 16x7 Fuchs w Michelin Pilot Sport A/S 3+, 205/55-16 at all 4 corners. Cars are for driving. If you want art, get something you can hang on the wall! |
||
|
04-13-2023, 03:53 PM
|
|
|
Registered
Join Date: Feb 2007
Posts: 7
|
I am going to try NGK BPR6ES plugs at .040 gap.
I will report back. Thanks for all the input. |
||
|
04-16-2023, 04:30 PM
|
|
|
Registered
|
Any update on your experience with the BPR6ES plugs at .040 gap. Been following this thread and based on Jeff's advice, which is always spot on, I purchased a set for my 72 T with MFI...that runs rich. It seems to be the for these cars...Wanted to know if these plugs with that gap will help avoid fouling.
|
||
|
04-23-2023, 05:46 AM
|
|
|
Registered
Join Date: Feb 2007
Posts: 7
|
So far so good with the NGK 6ES plugs at .040 gap, but don't have enough miles yet to comment on fouling. Runs great.
|
||
|
04-23-2023, 05:49 AM
|
|
|
Registered
|
Quote:
This can open a bag of worms . What are the choke sizes, e tubes , main jets , air correctors , idle jets and tubes ? Exact Float levels? Then the balance of the carbs ? Close is actually way off, work to get it exact. Ian
__________________
Kermit, 73 RS clone, Just Part of the Team Chris Leydon ,Louis Baldwin ,Peter Brock ,Riche Clark Jerry Sherman ,Rob McGlade ,Donnie Deal Hank Clarkson ,Craig Waldner ,Don Kean ,Leroy Axel Gains |
||
|
04-23-2023, 07:42 AM
|
|
