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Author Topic:   ? about platinum plugs
65chevy
Dirt Newbie

Total posts: 2
posted June 27, 2004 09:37 PM  
What plugs are suggested for pure stock dirt track racing?
Is there any know problem with running autolite platinum plugs?
Was told that wasn't recommended, now I want to know why?

Raz_900
Dirt Forum Champ
Total posts: 635
posted June 28, 2004 07:14 AM  
If you can get the right heat range, there shouldn't be any problem.

Personally, I use Autolite Racing or Accel plugs. Might switch to iridium's if I ever decide to spend the money, they'd last forever.

24s52
Dirt Maniac

Total posts: 122
posted June 28, 2004 07:28 AM  
I use Bosch platinum plugs. Always have, always will. Good plugs, but they do foul just like any other plug if things are not right.

KPLugnut
Dirt Forum Champ
Total posts: 1019
posted June 28, 2004 08:36 AM  
If you're having trouble fouling plugs, then read about these....
Silverstone Plugs

Silvertstone plugs, one of the only solid silver core spark plugs in the world. Used in Europe for years successfully, and just now being discovered here....

KP

[This message has been edited by KPLugnut (edited June 28, 2004).]

Pickel
Dirt Forum Champ
Total posts: 784
posted June 29, 2004 06:21 AM  
I started last year with the AutoLight racing plugs with the cut back electrode, I believe their were platinum also.
Spent like $4 a plug, Never could get the car to run on all 8 cylinders, every week i would foul a plug.

I went to the plain old standbuy, AC R45T, and ran the last 12 weeks on the same 8 plugs.

And this is in a 12.5 to 1, 406 Chevy.

Rookieracer76
Dirt Freak

Total posts: 289
posted June 29, 2004 12:43 PM  
i had the same problem pickel had. them darn plugs cost me a new 355. i now run the AC R45T like Flanndad and haven't had any problems!

Blackgold
Dirt Full Roller

Total posts: 71
posted June 29, 2004 07:01 PM  
Isn't the ac45 plug a pretty high heat range for 12 1/2 compresson? i've always run the AC43 heat range with 11 1/2 and higher compression.

J3
Dirt Maniac

Total posts: 188
posted June 29, 2004 08:12 PM  
What plug (heat wise) would you suggest to run for a 9.5:1 motor?

waltonjr1
Dirt Forum Champ
Total posts: 516
posted June 30, 2004 01:22 PM  
How often do you change your plugs? Ive been changing mine every three races when I change my oil.


rblracer
Dirt Roller

Total posts: 25
posted June 30, 2004 05:23 PM  
I've been looking at the Silverstone plugs that KP mentioned earlier, Anyone on here using them yet? If so tell us about it, I was thinking about trying them.

[This message has been edited by rblracer (edited June 30, 2004).]

UNVRNO
Dirt Maniac

Total posts: 136
posted June 30, 2004 09:10 PM  
quote:
Originally posted by Flanndad:
I started last year with the AutoLight racing plugs with the cut back electrode, I believe their were platinum also.
Spent like $4 a plug, Never could get the car to run on all 8 cylinders, every week i would foul a plug.

I went to the plain old standbuy, AC R45T, and ran the last 12 weeks on the same 8 plugs.

And this is in a 12.5 to 1, 406 Chevy.


THAT HOT OF A PLUG IN A REAL 12.5 - 1 MOTOR SHOULD PUT HOLES IN THE TOPS OF YOUR PISTONS PRETTY QUICKLY!!!!!


Flanndad
Dirt Freak

Total posts: 255
posted July 01, 2004 05:44 AM  
Hey UNVRNO, I looked it up again and it say's 12.515 to 1 compression.
I looked it up on the Keith Black Site,
KB 127 Pistons (12.5 To 1 w/ 64 cc)
64cc Pro Topline Heads
5.7 Rod
.030 Bore
Felpro 1034 Head gasket
SBC 400 Crank (standard stroke)

Maybe I'm doing something wrong on the compression ratio figures.

When I fouled the platinum plugs bad, the tech guy at the track, who builds alot of cars and raced late models for alot of years, said to put them in I did and the car never ran better.
The plugs also looked good, the insulators were off white with a slight brownish tint.

I'm not a plug guy, didn't really realize these were that hot of plugs.

Raz_900
Dirt Forum Champ
Total posts: 635
posted July 01, 2004 07:41 AM  
quote:
Originally posted by Flanndad:
Hey UNVRNO, I looked it up again and it say's 12.515 to 1 compression.
I looked it up on the Keith Black Site,
KB 127 Pistons (12.5 To 1 w/ 64 cc)
64cc Pro Topline Heads
5.7 Rod
.030 Bore
Felpro 1034 Head gasket
SBC 400 Crank (standard stroke)

Maybe I'm doing something wrong on the compression ratio figures.

When I fouled the platinum plugs bad, the tech guy at the track, who builds alot of cars and raced late models for alot of years, said to put them in I did and the car never ran better.
The plugs also looked good, the insulators were off white with a slight brownish tint.

I'm not a plug guy, didn't really realize these were that hot of plugs.


If you're running 115 octane fuel a tad to the rich side and keep coolant temp under 180, it might live with 45's.

Personally, I'd go for something in the R42-43 range. I use Autolite AR133s or Accel 262s in my 10.5:1 motors and they seem to work well too. Just don't let it idle when cold. They have a tendency to foul if left to idle very long within the first 2 minutes of a cold start.

Flanndad
Dirt Freak

Total posts: 255
posted July 01, 2004 08:13 AM  
I was running 110, I don't believe it was rich by the look of the plugs.

I was also running hot 210 to 220, until I got it figured out.

I'm looking at replacing the plugs, maybe I will go down a step or two and see how the plugs look.

Deak-Jr
Dirt Forum Racer

Total posts: 81
posted July 01, 2004 09:20 AM  
We were running 44's and had to rip the heads off this past week -- blown head gasket. We run a 355, flat-tops, stock heads, stock intake, Q-jet. Had been running hot (attributing it to the gasket). We went with the 44's off an educated guess from a plug catalog's specs on the 350. Would it be a good idea -- or hurt anything -- to try 43's, in general? Any ideas & suggestions welcome, thanks.

theslowguy
Dirt Full Roller

Total posts: 30
posted August 06, 2004 08:08 PM  
as a rule of thumb its always good to run the coldest plug you can without it fouling. keep going colder and colder till it fouls, then go back up one. and platinum and irridium plugs take alot more juice to fire than a standard plug so if you are running stock hei, stay away from them. you'll have much more efficient spark with standard plugs.

cobb
Dirt Maniac

Total posts: 131
posted August 06, 2004 10:25 PM  
i run 42, i'd rather foul $8 worth of plugs than cook a motor

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