mike13

iTrader: (27)

I have a stock ls1 with headers with a magnacharger MP112, will changing to a set of 243 heads add any power? I know it will probably lower the boost but will it actually add any horsepower & torque?

JRENIGAR

iTrader: (37)

Sure, due to more compression and better flowing runners, but why would you do this? You will probably have to run a larger pulley to make less boost or detonation will occur. I personally would go with 317's to lower the cr then add more boost. You have a roots type charger so low end torque will not be a problem.

mike13

iTrader: (27)

take a few degrees of timing out of the tune. It's only a MP112 so it would only see single digit boost numbers.

2000RATA

I don't believe you would see any real gain meaning seat of the pants. It's probably measurable on a dyno but not worth your time. If the exhaust flowed enough better on the 243's vs. the 241's I might be inclined to try it but they don't. A ported set of 241's would be perfect. I've made 500 rwhp with them n/a.

JRENIGAR

iTrader: (37)

Wouldnt that diminish any hp gains you would see from the higher CR? This is what my tuner told me about going from 853's on my car to a set of 243's I bought on the cheap.

mike13

iTrader: (27)

I don't think so, my friend is running his vortech @8lb's with 243's on a stock shortblock, pulled a couple of degrees at peak torque to be safe. There's alot more information out there now about running higher static compression at lower boost levels. Before you would sacrifice out of boost power with lower compression and pulled timing. We are only talking a 500hp set up which is not much more than a high dollar h/c/I combination.

Sales@Tick

iTrader: (3)

Exactly, cylinder pressure will not be high enough in this build to warrant low compression.

Mike, you know my thoughts on this subject already...

mike13

iTrader: (27)

Thanks, when it comes to small roots style superchargers it's different. It's like trying to suck as much milkshake as you can thru a straw without hyperventilating.

Sales@Tick

iTrader: (3)

Which is exactly why I told you that overlap is the enemy on this exact set-up.

Imagine sucking through that straw with a bunch of holes in it above the actual milkshake and those holes end up bleeding off what pressure you have. You begin to struggle harder and harder to pull in the same amount of air mass(in this case milkshake mass lol) and you end up overworking yourself for less gain.

Same principle.

JRENIGAR

iTrader: (37)

Well dang, shot down like Jessie James.

mike13

iTrader: (27)

Hey it's all about sharing information.

91sonomast

Gotta learn somehow. I'm glad you asked cause I learned as well. So in the case of a 5.3, going from the 862's to the 241's, would that make sense as the 241's flow considerably better and have bigger intake valves? Granted you lose compression.

JRENIGAR

iTrader: (37)

yeah, I hear ya. I just remember my tuner saying I wouldnt benifit enough to justify swapping my 853's to some 799's that I got off a late model 5.3 engine for cheap so I sold them.

Sales@Tick

iTrader: (3)

Stock to stock I don't think it would be worth much if anything.

Ported is a different story though...

JRENIGAR

iTrader: (37)

Thanks for the info Martin.

Sales@Tick

iTrader: (3)

Not a problem.

punishmentcycle

iTrader: (6)

The 112's do like higher compression.. You'll continue to make power and torq the higher u go on compression but then u will eventually hit the cfm and thermal wall of the baby blower. Just get ur quench dead nuts to keep detonation at bay.