I am definatly going to try and replace the coils in the 3.4 to the L67 ignition coils. alot of people said they get a better spark from it at higher rpms.
I prefer to just get them new because the engine only has 35k miles on it.
After a bunch of searching, i ended up with gm part number 10477602

can someone confirm this please-

 

This is what I saw on web...

10477602 COIL. Ignition Coil
COIL,IGN(ACDelco #D576). Required: 03For: W 3.8-1(L67) (2004-2004). For: W 3.8-1(L67) (2004-2005).

 

I understand the want to go with new coils. One thing to keep in mind, the true L67 coil looks just like the ones you have now, but on the underside you should have a gray terminal and the L67 ones have a blue terminal.

My opinion is it's a nice mod, but I don't feel it's worth more then $30 invested in it. The L67 and non-L67 coils are SUPER reliable and have a huge longevity. All three of my cars that can rum L67 coils have salvage ones and I did not pay more then $30 a set. They have about 100,000 miles on them, worked great when I put them on and still work great. I have them on a L36, a 3100 and a 3400.

Just food for though.

 

on the 3.4- would the l67 coils give any more horsepower?

 

Anyone know a good place to pick these coils up for cheap? Found junk yard ones on ebay for like $75. I would prefer not to spend that much on used parts.
It's cold here and crawling around the junk yard is not fun this time of year. If anyone has a source for cheap, that would be great!
If I have to wait till warmer weather then I will.
Thanks!

 

I'm planning on just going to the junk yard to get them. Its cold but carhatts help

 

Haha! I hear you about the Carharts! I've got a carhart hooded/lined sweatshirt and a jacket. Time to break 'em out!

 

It's tough to say if they add HP. They do improve throttle response a little bit (specifically in the higher RPMs).

 

From what i remember with engine stuff in the back of my head and please correct me if im wrong.

The faster the rpm, the faster the spark has to be produced and at those faster rpms, its very possible that the spark is weaker- not firing the optimum combustion that the engine normally produces at say 2000 rpm..

Just like when replacing the valve springs to a stronger spring, you wouldnt be gaining anymore horsepower by adding the mod, but you are enabeling your engine to work more efficiently at higher rpms.