Swartlkk, Thanks for correcting me about the spacer. I do agree that in doing these things to a 00 4.3 one at a time a person might not get the advertised resaults. But, and most builders know this, as i'm sure you do to. It is piecing together the right combination of parts where a build will see it's best gains. Most experienced people also know, to make more power without changing the displacment, you need to make the following happen. Get the engine to breath better- Air filter, air intake (even cold air), cam ( in. ex. dur, and lobe sep) and more importantly getting spent gasses out of the engine- headers high flow exhaust system...
More fuel. duh.
and how many guys do you know that build a nice piece and run stock ignition on it.
I'm not here to mislead people. Just to bring my experience to the table. I did a 4.3 3 years ago. it was .30 over and before i put i put 18 degree little brodies on it, I ran stock heads with 1.55 rockers and good valve springs and everything I mentioned was done and my rwhp was 289. no power adders at all untill the heads were on. MSD rev limiter at 7700 and would do it all day long.

I'm not trying to be a smart *** on your forum. but these things, when done right, do make a big different.

 

Just to complete my last post that engine was in a 00 s10 extreme. When the engine was done it was a carbed, blow thru procharger p1sc on E85. Oliver rods (had to be machined to make narrow) Wiseco Ultra-lites, 18 degree headers made by Headers by Ed here in Minneapolis, Jesel mount valve train (that had to be done with the heads) and 18 degree GMPP single plane hi rise, holley 750... it was wicked. I bought most of my parts from racing junk.com

 

No doubt they will make a huge difference. It comes down to the choices you make.

My response to the ignition side of this was related the fact that both MSD and Accel make stock replacement ignition parts that, IMHO do not offer any advantages over OEM components and in my experience do not hold up as well as OEM components. Replacing the ignition system with a full MSD setup will net you some good gains once you have out grown the stock setup. But the days were stock setups on GM vehicles were weak is gone, hopefully for good. The newer ignition systems are HOT and react very well to higher RPM operation.

 

it's an old method they used to do it on racing cars,
u can instal a 1cm neck on the BUTTERFLY ,it's where the air intake pipe ends on the engine, so this plastic cover you can make it higher by adding a round neck WITH SAME DIAMETRE of course, each millimetre higher makes a difference.. so how about 1cm lol .. i tried it, I HAD TO UPGRADE MY BRAKES ahaha .. too much power.. but remembre it's a 4x4, cranks and pistons might be damaged!!

 

I believe by "neck" you are describing a spacer. If so, read above.