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Backfire on a 3800 SC: How bad is it?

SaukRapids

SaukRapids

I can't car too good.
I've owned 3 GTP's and had the u-bend/downpipe upgraded. All three cars (the '97 probably had the least issue) would backfire if the throttle was cut at about 30mph.

It can happen deliberately but also happens getting into traffic. So how hard is it on the internals, like "maybe don't do that" bad or "get it tuned out now" bad?
 


My car always did it if I romped it real quick and let off the gas around 15-25mph.

Being catless with headers made it real easy to hear the quick pop. My thoughts is that it's because there is still extra fuel that could be burned off and the waste spark ignition system would lite the fuel off in the rear header/downpipe. Never hurt anything in the 3 years I had headers.
 
I'd say its like taking a tack hammer and giving the resonator a solid tap, about that loud. I did find out the '99s trans went out some years later, but still ran just fine like that.

It can't be good for the engine. I can see it being hardest on the valves. So.. maybe "moderation" in applying full, then cutting the throttle?

It's kinda hard for me to picture what's exactly going on during this type of misfire.
 


Fivefingerdeathpunch said:
waste spark ignition system
Click to expand...
Reading...It's answering the spark condition.

What's this about premature wear on copper plugs? I know that 104's will have to be replaced more frequently. I'm also fairly certain they work totally fine in these cars. This link looks like it could be rather dated - http://www.aa1car.com/library/sparkplugs_for_dis.htm

This link was also helpful regarding the ignition system - http://www.greatautohelp.com/auto_basics/3800-Ignition-Operation-Description.html
 
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If that's all the louder it is, it probably will never hurt anything. However, if you have a tuner, it might not be a bad idea to try and tune it out. I can't say that I've ever had a car do this before.
 
Are you talking about after fire or back fire into the TB? Mine after fires into the tail pipe all the time if i let off at around 35km/h and it sounds really sweet. never in my time have i heard of after fire hurting a car. now back fire yes.....
 
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