quote:

Originally posted by markemark:
You're using Autolite AR3933 ? I don't read plugs, just replace. I read my DA and ET slip.

Yes. Never an issue with them....time slip doesn't tell all though....

My Siebert 414 14:1 sbc was built and dyno'd with -8 plugs. I had some RPM noise on the data logger using NGK and switched to AR3934's and now have no noise.

quote:

Originally posted by Coloradoracer:

quote:

Originally posted by markemark:
You're using Autolite AR3933 ? I don't read plugs, just replace. I read my DA and ET slip.

Yes. Never an issue with them....time slip doesn't tell all though....

What are these telling you? They’re telling me read the time slip..

quote:

Originally posted by markemark:

quote:

Originally posted by Coloradoracer:

quote:

Originally posted by markemark:
You're using Autolite AR3933 ? I don't read plugs, just replace. I read my DA and ET slip.

Yes. Never an issue with them....time slip doesn't tell all though....

What are these telling you? They’re telling me read the time slip..

A couple of those are telling me to do a leakdown...Then start pulling the engine....

^^^^^^ That 500+ run sbc (and those original spark plugs) still ran very close to same ET as new using MFI and a primer+ plate. Those NGK plug gaps started out at .030” and finished at .043”+.

My present engine has 500+ runs now and going to 1000 before rebuilding. I am going to change spark plugs and just purchased the AR3933 from RockAuto to try. These Autolites come pre-gapped at .025” and installing this way.

My present engine has been switched from MFI to EFI in July 2021 and curious what spark plugs look like. Still runs same ET’s.

RockAuto has a 5% discount code 202840473183425305 that is good until June 19, 2022 and can be used by anyone.

Ya read plugs on a new combo to get the mixture right by making at least a thousand foot pull on new plugs, *as has been said* NGK are easy to read methanol engine shut down at the stripe.

Once your mixture is right (plug looks good), you'll have a consistent car. To tweak from there is a 1/2 degree timing here or there, or maybe a tiny jet or bleed addjustment.

After that you can forget about looking at em. I run AR's for many years as well as NGK. I like a NGK better even though by a wide majority ofthe time, I ran AR's. The AR's lose their gap setting over time.

I run the same set NGK plugs today .015 total or better Super Pro bracket racing, as I ran 5's with in 2017, for an example of how often I change spark plugs.

This message has been edited. Last edited by: Mike Rietow,

quote:

Originally posted by markemark:
^^^^^^ That 500+ run sbc (and those original spark plugs) still ran very close to same ET as new using MFI and a primer+ plate. Those NGK plug gaps started out at .030” and finished at .043”+.

My present engine has 500+ runs now and going to 1000 before rebuilding. I am going to change spark plugs and just purchased the AR3933 from RockAuto to try. These Autolites come pre-gapped at .025” and installing this way.

My present engine has been switched from MFI to EFI in July 2021 and curious what spark plugs look like. Still runs same ET’s.

RockAuto has a 5% discount code 202840473183425305 that is good until June 19, 2022 and can be used by anyone.

I thought you were being sarcastic with those Mark...

If I had those plugs in my engine it wouldn't even idle....

2 of them look oil fouled on top of the carbon fouling to boot.

And I just want to drop a duce on Rock Auto while I have the chance.

I tried to order NGK's from them awhile back and they shipped them to the wrong address and still charged me for the shipping.

That's is twice for me with them screwing up an order and they have piss poor non existent customer service. Screw Rock Auto.

I just have a parts store like Auto Zone or someone price match them.

quote:

Originally posted by markemark:


I am going to change spark plugs and just purchased the AR3933 from RockAuto to try.

If you don't mind me asking, why would you do that based on your whole description of how these NGKs worked?

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If you don't mind me asking, why would you do that based on your whole description of how these NGKs worked?

I’ve never used Autolite Racing spark plugs and being curious wanted to try. Their strap is cut shorter than NGK and start with a slightly smaller gap. That’s why I asked if others were using successfully. This is a perfect time for the last 500 runs and can switch back if problem occurs. I don’t index spark plugs, just screw them in.

quote:

I thought you were being sarcastic with those Mark... If I had those plugs in my engine it wouldn't even idle....2 of them look oil fouled on top of the carbon fouling to boot.

imho if your ignition is working properly your engine shouldn’t have any problem running on what I took out. I’ll post a pick of the set I removed after the Autolites go in.

The dark color is normal from the primer+ plate using 93 octane when not on methanol.

quote:

Originally posted by markemark:

quote:

I thought you were being sarcastic with those Mark... If I had those plugs in my engine it wouldn't even idle....2 of them look oil fouled on top of the carbon fouling to boot.

imho if your ignition is working properly your engine shouldn’t have any problem running on what I took out. I’ll post a pick of the set I removed after the Autolites go in.

The dark color is normal from the primer+ plate using 93 octane when not on methanol.

I am WAY WAY lean then!!!!

I run a toilet with a primer+ and 93. I set mine up so its a bit hard to keep running when its cold. I actually fatten it up with some alky at first till it gets some heat in it then finish building temp with gas.

quote:

Originally posted by moparacer:I am WAY WAY lean then!!!!

I run a toilet with a primer+ and 93. I set mine up so its a bit hard to keep running when its cold. I actually fatten it up with some alky at first till it gets some heat in it then finish building temp with gas.

Yours sounds perfect for initial start of the day or when needing heat.

I drive around the pits / return road after run with PP and it’ll run to 3000 rpm before it cuts out from being too lean. Seldom is my injection On when off the racing surface. I can drive it up into the trailer on PP.