Community Forums

FullAstern · 06-11-2007, 12:57 PM

I was up near Akron yesterday and thought I'd stop in at Summit Racing and get a set of Taylor Extreme 99615 wires, AC 41-932 plugs and some Moroso washers to index them. Has anyone been to a Summit Racing retail store??? Oh my god! They're a giant monument to go fast parts. This place is enormous; with ultra expensive pieces parts lying about like so many nuts and bolts. I passed isle after isle of Brodix, Dart and Trickflow heads and blocks. Edelbrock and Mahle pistons; Manley valves and rods were neatly laid out on shelf after shelf. You like supercharges? Just take your pick. They had half a dozen race, show and hotrods sitting there. Not your normal ones either. These were in the multi hundred thousand dollar range. There was a rod there with 4 wheel drive, pushrod inboard suspension and an engine I can only guess that was worth its weight in gold. Do you want a 572 CID, 650hp Chevy crate engine? Just point one out and they'll drop it in the bed of your pickup...just give them $18,000 bucks first. They had a bunch of those. It's pretty neat to see why the 8.1 most us share is such a cool engine when you see the heads. Those porcupine valves look just like Ford Boss 302/351 heads, just bigger, much bigger. The small block Chevy looks positively anemic next to it.
I went to the cashier, gave them my list and it was quickly and efficiently fished out of the attached warehouse. Did you ever see the movie Raiders of the Lost Ark? At the end of the movie they wheeled the Ark into a bottomless pit of a warehouse to become lost once again. I think it's the Summit warehouse. The place is ultra clean and incredibly staffed. I was in London last year and went to Harrods. That place has more employees than customers. You just look like you may perhaps have a question and there was someone at your elbow asking to help. Summit wasn't quite there yet but it sure wasn't like going to Pep Boys. Summit seems to have bought its own race track as well. Nice place to do a parts test I guess.
Anyway, I put the wires on, gapped the plugs to .045 and indexed them. It is the first time I've ever seen a difference from a spark plug change. I've tried all the gizmo plugs over the years and saw nothing. The MH has noticeably more power and it looks like I've picked up maybe a mile per gallon. I'll have hard numbers after I tow my sailboat to the lake tomorrow or so. I've made that trip many times and I know exactly what MPG I get. I doubt the wires had much to do with it but they are very cool, if really expensive. I've never had the burnt plug wire syndrome but I can't imagine how that would ever happen with these wires, careful routing and the stock plug heat shields. I've always indexed my plugs so maybe this engine like that with the 41-932's and a 0.045 gap. Either way, it definitely does seem to give a noticeable improvement. If you're looking at changing the plugs, one tool I found really, really helped. I bought a Stanley rotator ratchet that worked shockingly well. There was almost no space to swing the handle to spin the plug in or out. With the rotator ratchet I just twiddled the handle. In tight areas it was invaluable to keeping knuckle skin. I looked at the intake spacers but that seems to be like nonsense to me. I remember a pinwheel gizmo some years ago called, I think, a Swarup that you put in your intake ...I think it falls in the same category as that or putting magnets on your fuel line.
Well, thanks for the patience in reading through this. I can't recommend a Summit visit highly enough for those who like that sort of thing. It's got nothing to do with RV's...it's all about horse power, lots of horse power and money, lots of money.

FullAstern · 06-11-2007, 12:57 PM

I was up near Akron yesterday and thought I'd stop in at Summit Racing and get a set of Taylor Extreme 99615 wires, AC 41-932 plugs and some Moroso washers to index them. Has anyone been to a Summit Racing retail store??? Oh my god! They're a giant monument to go fast parts. This place is enormous; with ultra expensive pieces parts lying about like so many nuts and bolts. I passed isle after isle of Brodix, Dart and Trickflow heads and blocks. Edelbrock and Mahle pistons; Manley valves and rods were neatly laid out on shelf after shelf. You like supercharges? Just take your pick. They had half a dozen race, show and hotrods sitting there. Not your normal ones either. These were in the multi hundred thousand dollar range. There was a rod there with 4 wheel drive, pushrod inboard suspension and an engine I can only guess that was worth its weight in gold. Do you want a 572 CID, 650hp Chevy crate engine? Just point one out and they'll drop it in the bed of your pickup...just give them $18,000 bucks first. They had a bunch of those. It's pretty neat to see why the 8.1 most us share is such a cool engine when you see the heads. Those porcupine valves look just like Ford Boss 302/351 heads, just bigger, much bigger. The small block Chevy looks positively anemic next to it.
I went to the cashier, gave them my list and it was quickly and efficiently fished out of the attached warehouse. Did you ever see the movie Raiders of the Lost Ark? At the end of the movie they wheeled the Ark into a bottomless pit of a warehouse to become lost once again. I think it's the Summit warehouse. The place is ultra clean and incredibly staffed. I was in London last year and went to Harrods. That place has more employees than customers. You just look like you may perhaps have a question and there was someone at your elbow asking to help. Summit wasn't quite there yet but it sure wasn't like going to Pep Boys. Summit seems to have bought its own race track as well. Nice place to do a parts test I guess.
Anyway, I put the wires on, gapped the plugs to .045 and indexed them. It is the first time I've ever seen a difference from a spark plug change. I've tried all the gizmo plugs over the years and saw nothing. The MH has noticeably more power and it looks like I've picked up maybe a mile per gallon. I'll have hard numbers after I tow my sailboat to the lake tomorrow or so. I've made that trip many times and I know exactly what MPG I get. I doubt the wires had much to do with it but they are very cool, if really expensive. I've never had the burnt plug wire syndrome but I can't imagine how that would ever happen with these wires, careful routing and the stock plug heat shields. I've always indexed my plugs so maybe this engine like that with the 41-932's and a 0.045 gap. Either way, it definitely does seem to give a noticeable improvement. If you're looking at changing the plugs, one tool I found really, really helped. I bought a Stanley rotator ratchet that worked shockingly well. There was almost no space to swing the handle to spin the plug in or out. With the rotator ratchet I just twiddled the handle. In tight areas it was invaluable to keeping knuckle skin. I looked at the intake spacers but that seems to be like nonsense to me. I remember a pinwheel gizmo some years ago called, I think, a Swarup that you put in your intake ...I think it falls in the same category as that or putting magnets on your fuel line.
Well, thanks for the patience in reading through this. I can't recommend a Summit visit highly enough for those who like that sort of thing. It's got nothing to do with RV's...it's all about horse power, lots of horse power and money, lots of money.

DriVer · 06-11-2007, 01:23 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by FullAstern: </div></BLOCKQUOTE>Thank you!

edgray · 06-11-2007, 04:26 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I've always indexed my plugs..... </div></BLOCKQUOTE>
Great post! But, I wish you would develope some enthusisam

For those of us who are not total gear-heads, can you please explain "indexing"- what it is and what it does? Thanks, ED

Bucky1 · 06-11-2007, 04:55 PM

There are different reasons for indexing. One that we use in racing is for piston clearance. If you position the electrode, usually with the gap toward the exhaust valve, you get a little extra clearance between the plug and piston. It doesn't sound like much, but it is needed in some tight engines.

Full-Timers · 06-11-2007, 06:58 PM

Indexing is a method of positioning the spark plug electrode inside the cylinder by using difference sized washers between the plug and the head. I think it's more for positioning the electrode for best ignition of the fuel.

I can't believe it would make that much difference in a motorhome to go through the hassle.

"007" · 06-12-2007, 02:54 AM

How would know what size washer to use for proper indexing of each spark plug location?

Bob (WA0MQE) · 06-12-2007, 03:51 AM

I'll second "007", How do you know what size (thickness I guess) washer?

Who else might carry the AC 41-932's? Also, did you torque the plugs and if so how much?

troth · 06-12-2007, 05:01 AM

I believe the indexing is done by trial and error method, removing & reinstalling each plug a few times to get the correct position.

FullAstern · 06-12-2007, 05:43 AM

Sparkplug indexing can make a difference in some engines, some a lot, others not so much. There are too many variables to say it's universally wonderful. Combustion chamber shape, number of valves, the location of the plug or plugs (Remember, the new Chrysler hemi has two plugs per cylinder), compression ratio, piston dome shape, etc. In that maze all combine to make everything behave differently. Sometimes
Anyway, indexing is easy once you have a process. If you have easy eyeball access to see the plug insulator after the plug is installed, all you have to do is to mark where the open end of the electrode is on the plug. There is no rhyme or reason as to where the electrode is in relation to the way the threads are cut, on the plug or in the cylinder head. Any plug can end up pointing any direction in at any cylinder. The old, stupid and expensive way to do it was to screw various plugs in till you found the one that pointed the electrode in the right direction. The new and easy way is to buy a $15.00 washer kit from someone like Moroso, (http://www.moroso.com/catalog/catego...?catcode=41011) there are many others. The washers are specific to plug size and shape. For the 8.1 you need Moroso PN#71900. They fit 14mm tapered seat. It's easy to see what fits what.
The Moroso kit comes with 30 color coded washers of 3 different thicknesses, .010, .021 and .032. Each step changes where the plug stops by a bit less than a third of a turn or about 105 degrees. So all you do is put the plug in, torque to about 10 ft/lbs and see where the line you marked is. In our case, the 8.1 liter, you want the electrode to point up and to the right about 20 degrees more or less. Then just remove the plug and put the correct size washer on it to make it point there. It's not required that you stack the washers. After the first one you'll have it down pretty quickly so make the first plug you do the easiest to get to get to as you may have to install and remove it more than a few times till you figure it all out.
Ok, so now you've discovered that it's impossible to see the plug when it's screwed in to the head. One of those little mirrors on an extension may help but probably not. In this case you have to mark the sparkplug socket and even the various extensions you'll be using. The only problem is...DON'T LET THE SOCKET COME OFF THE SPARKPLUG! If you do you'll have to take the plug out and realign the electrode and your socket/extension marks. In fact, I do it this way most of the time anyway, ˜cause you almost can never see the **** plug. A nice bright flashlight is usually very helpful.
This all sounds awful but it's no worse than just doing the plugs. The worst part for me was getting the old plug wires off. The rest is more finesse than force.
There are numerous websites sites that give really good and clear explanations and pictures:
http://www.fordmuscle.com/archives/2000/07/indexplugs/
http://www.advanceautoparts.com/engl...20001001sp.asp
http://www.dodgeram.org/tech/gas/spa...0_indexing.htm

jbrnigan · 06-12-2007, 06:33 AM

FullAstern - VERY COOL!! I love this place.

edgray · 06-12-2007, 08:19 AM

FULLASTERN: Thanks for answering my questions. That was another great post! ED

max49 · 06-12-2007, 03:18 PM

So indexing with a washer on the bottom of the plug lowers the compression? If so, is that a good thing?

FullAstern · 06-12-2007, 03:49 PM

Hmmm....I don't think you could measure the compression change if any. I really, really wouldn't worry about that. There is a process called CCing the combustion chamber. It's a racers rick to make each combustion chamber exactly the same size and shape with the valves installed. The variation in as cast cylinder heads combustion chambers can be quite alarming if you're expecting exact uniformity. Normal variation combined with carbon build up on the piston dome, etc, etc makes anything a .021 washer on a sparkplug could cause virtually unmeasurable.