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Sparkplug gap?

  
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Sparkplug gap?

 
lagarbo89fxrs lagarbo89fxrs
New User | Posts: 1 | Joined: 10/09
Posted: 10/09/09
04:39 AM

Hi All,was hoping someone can give me some advice regarding what i should set the gap on a motor I just put in my 76 camaro. The block is a 4 bolt main out of a 79 chevy truck, the cam and crank is street/strip, the heads are world sportman II, hypertech coil/dist, headers, rpm air gap manifold, 750 holley d.p. with a 4 speed and posi- rear end. I'm using the accel shorty plugs which were pre-gapped at .35. Was wondering if that gap is o.k or if I should widen the gap and what difference if any a wider gap would make. Thank you for any info I really appreciate it.  

 
p2-72chevelle383 p2-72chevelle383
Enthusiast | Posts: 301 | Joined: 08/09
Posted: 10/09/09
05:15 AM

i usually gap mine at 35  

 
Pontiacman2 Pontiacman2
Guru | Posts: 843 | Joined: 09/08
Posted: 10/09/09
05:48 AM

I gap mine at .045  
Horsepower sells Engines and torque wins races.

 
SMOKESHOW SMOKESHOW
Guru | Posts: 958 | Joined: 09/08
Posted: 10/09/09
05:56 AM

well we all are pretty close I gap min at .040  

 
Dave632 Dave632
User | Posts: 111 | Joined: 07/08
Posted: 10/09/09
04:04 PM

It also depends on your ignition system. When I was running the MSD 7 with thier matching coil they suggested a gap of .080. I imagine the reason they suggest that is for the bigger spark it gives you and the fact that thier system is much more powerful than a stock one.
The other factor you must consider when gapping plugs is the RPM range you will be running. When I ran an older stock system and was reving over 7000 I would gap my plugs closer, .030, since at higher RPM the coil has less time to saturate and a shorter gap is easier to jump.
Modern ignition systems are much better so if you are running aftermarket ignition I would check with the manufaturer and see what they recommend.  

 
skyeking skyeking
User | Posts: 54 | Joined: 08/09
Posted: 10/10/09
03:58 PM

Hi There,
      What leads are you using? I find that 8.8mm Top Gun and plug settings of
      32-35/1000" are long lifers IF you are NOT a full time road Warrior.
        With this combo I never had a cleaning session with the dizzy cap for
      over 3 years as a daily driver averaging 1200 miles a month. Skyeking  

 
gettnlarge01 gettnlarge01
Enthusiast | Posts: 653 | Joined: 09/09
Posted: 10/11/09
05:16 AM

If your compression ratio is under 9.5:1 then .040-.045 will work fine with your set-up.  

 
mpayne mpayne
Administrator | Posts: 632 | Joined: 10/07
Posted: 10/13/09
03:14 PM

Thanks for all the info guys.  

 
SMOKESHOW SMOKESHOW
Guru | Posts: 958 | Joined: 09/08
Posted: 10/13/09
06:29 PM

Static or dynamic at 9.5:1?  

 
gettnlarge01 gettnlarge01
Enthusiast | Posts: 653 | Joined: 09/09
Posted: 10/14/09
02:27 AM

I said I dont use STATIC compression that doesnt mean I dont know what it is. Would you care to explain why you think static is  more accurate than dynamic?  

 
SMOKESHOW SMOKESHOW
Guru | Posts: 958 | Joined: 09/08
Posted: 10/14/09
05:02 PM

I don't think that at all.  I just never really thought about how misleading the specs can be at times.  No ball bustin intended here.  

 
gettnlarge01 gettnlarge01
Enthusiast | Posts: 653 | Joined: 09/09
Posted: 10/14/09
05:10 PM

No prob. Cam companies are very misleading. Think about the fact that they recommend the same cam regardless of engine size for a specific RPM. A cam that pulls strong to 5500rpm in a 283 will not do the same in a 400. Its all generalized for the masses! lol  

 
SMOKESHOW SMOKESHOW
Guru | Posts: 958 | Joined: 09/08
Posted: 10/14/09
05:21 PM

indeed!  

 
gettnlarge01 gettnlarge01
Enthusiast | Posts: 653 | Joined: 09/09
Posted: 10/14/09
05:27 PM

Cam companies generalizing things makes my job harder because some people think its a golden rule to follow.  

 

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