Which heads do you recommend to complement a Magnacharged 6.0L LS2 with a stock bottom end?

I ask this question in reference to my plans for my '07 Trailblazer SS. I am planning on installing a MP112 Maggie on my TBSS along with a ported & polished LS7 throttle body, e-fans, 160* T-Stat, Katech belt tensioner, NGK TR-6 plugs, Kooks 1-7/8" headers w/ catted Y-pipe, custom 3" exhaust, and a custom tune. Keep in mind that this is mostly a daily driver and I am trying to obtain the sleeper effect.

I was wondering if it would be worth the extra money to upgrade the heads and cam while I was in there? I realize and understand that the Maggie likes compression, since the Maggie was not built for big boost, so the LQ9 317 heads are out of the equation. I would like to maintain the stock compression as it seems to be well suited for a maggie but was concerned about the stock LS2/243 heads restricting the flow. I could sell the stock heads to offset some of the cost but just wanted some experienced opinions beforehand. So do you recommend upgrading to aftermarket heads or just stick with the stock LS2 heads? Also are larger runners better for the Maggie? The aftermarket CNC'd 243 casting heads vary in their intake runner size so what is the best for the Maggie 210, 220, 230, 240? Also what about valve size, is the stock valve size ideal or bigger valves? What cam specs do you recommend, specifically, as I know ECS, A&A, and LG make custom grinds but I want to personally know what specs you guys are running with your maggies.

My apologies on all of my questions as this is my first forced induction build. I am just trying to learn along the way. I believe I know what you are going to recommend but I just have to ask the experts first to verify my thoughts. Thanks in advance for any advice.

 

https://ls1tech.com/forums/showthrea...85#post7931685

Here's a link to a thread with dyno graphs showing an F-body with our CNC ported 243 castings, and speed inc's SC2 camshaft. This car made very good torque, and pretty good horsepower. It dooes have stock sized valves, and higher HP numbers would be achieved with bigger intake and exhaust valves. The nice thing is these heads are made from new GM castings, and sell for 1299.00 outright, so you could sell your stockers and recoup some of the cost.


Ed

 

on my ls1 i have the 243 castings from prc and texas speed. Needless to say it is the second highest horsepower ls1/ls6 with a maggie that i know of. Texas speed i belive has some now for the ls2 motors.

 

Thanks for your reply and congrats on your setup...
What are your intake and exhaust valve sizes?
What are your other supporting mods?

I was mainly interested in what was considered to be the ideal valve sizes for a stock bottom ended LS2 topped with a maggie and a small blower cam...

 

Ms4 cam/kooks 1 3/4 headers/ 90mm throttle body/ slp lid/ 3.2 pulley 6psi/the prc 243 heads no milled stock bottom end doubble roller.

 

What is your RWHP? I know of a couple that makes some pretty good RWHP. One guy I know is running N20 and making around 654RWHP/680RWTQ . I know of someone else making 599 RWHP with his 402.

 

He's talking about the LMS kit he has on his camaro. I believe his is in the 570 range or so. I'm sure if you search under his profile the numbers are around there somewhere. ( the link below is of 97 Z Me Go)

Who is the highest by the way for the LMS kit?

https://ls1tech.com/forums/showthrea...t=#post7789954

 

I would not recommend a stock maggie kit for an over 6.0 motor. You will pay 90% of the price of a great setup, but not get the subsequent return. The 112CI blowers start to run out of steam in the same vicinity as the peak #'s you can get from an N/A 6.0 (yes, I know the low end torque isn't the same, but it is un-useable anyway). Their new 122CI blowers should be much better, but still not the HP/$ value available from other setups.

 

go for the 122ci

 

I believe he was talking about F-bodies with Maggies, in which case his is #2

Ed

 

IF and F body and a C5 vette had the exact same motor and power, wouldn't the F-bodies show more RWHP than the C5's due to the IRS?

 

I really don't know the percentage of difference in driveline loss between an IRS and the standard 10 bolt posi, but I would have to say it's minimal on a chassis dyno. I've dyno'd alot of both in stock form, and a stock LS1 makes roughly 300 in a Vette or an F-body

now if the two cars had the exact same motor and power, I would think the F-body would ET better due to the solid rear.

Ed