Do you guys think 1-3/4" headers are hurting power on a LSA supercharged LQ4 with a 220/228 cam, pushing 11psi?

The motor also has stock 317 heads, adapter plates for the blower, CTS-V lid, 90mm throttle body, 4" intake tube, and LS7 MAF. I'm looking for ideas on what I can add or change to make more power.

 

Maybe some.

But if you swapped from what you have to 1 7/8th headers with nothing else done it's not going to make gobs more power, in fact it could be pretty close to the same.

Just up the boost to make more power.

 

I can't up the boost anymore. The pulley combo is maxed out with a 2.45 blower pulley and a 10% overdrive balancer.

 

Depends on what's after the headers. If a stock exhaust and cats, then no. A free flowing straight through muffler setup, there might be a few hp to be gained, but probably not a lot.

 

Exhaust is dual 3” with Borla XR1’s, so it’s pretty opened up.

 

I'd say it's probably not worth the cost to upgrade unless you can sell your current setup for a near-new price.

 

You might consider a larger MAF and TB first.

 

The card style MAF is fine, can't go any "bigger" with that but a larger throttle body would do some good.

 

The LSA blower design chokes the TVS rotor pack unless it has been ported. If that has not been done to your blower that's a slam dunk mod at this point. That and going to a 102 while you are at it. To prove that point, I made 14psi on my 05 denali with a VERY similar combo with a 2.7" upper pulley with a magnuson 1900. Seeing as youre in DE I am going to assume weather/altitude is a non factor.

On another note, if you want more blower RPM you need to change to LSA accessories so you can fit a larger lower ring on it.

Now back to the original question... not worth the cost to upgrade unless a used set were to fall in your lap. The stuff listed above will make a much more drastic difference in power. What headers do you have exactly?

 

What Rob said, porting the blower and snout are some gains. Alot of CTSV/ZL1 guys do those mods to gain more. Heres a guy that can do exactly what your looking for

https://www.facebook.com/jokerzperformance